Economic Analysis of First-Line Treatment with Cetuximab or Panitumumab for RAS Wild-Type Metastatic Colorectal Cancer in England

Abstract

Background

Combination therapies with cetuximab (Erbitux^®; Merck Serono UK Ltd) and panitumumab (Vectibix^®; Amgen UK Ltd) are shown to be less effective in adults with metastatic colorectal cancer who have mutations in exons 2, 3 and 4 of KRAS and NRAS oncogenes from the rat sarcoma (RAS) family.

Objective

The objective of the study was to estimate the cost effectiveness of these drugs in patients with previously untreated RAS wild-type (i.e. non-mutated) metastatic colorectal cancer, not eligible for liver resection at baseline, from the UK National Health Service and Personal Social Services perspective.

Methods

We constructed a partitioned survival model to evaluate the long-term costs and benefits of cetuximab and panitumumab combined with either FOLFOX (folinic acid, fluorouracil and oxaliplatin) or FOLFIRI (folinic acid, fluorouracil and irinotecan) vs. FOLFOX or FOLFIRI alone. The economic analysis was based on three randomised controlled trials. Costs and quality-adjusted life-years were discounted at 3.5% per annum.

Results

Based on the evidence available, both drugs fulfil the National Institute for Health and Care Excellence's end-of-life criteria. In the analysis, assuming discount prices for the drugs from patient access schemes agreed by the drug manufacturers with the Department of Health, predicted mean incremental cost-effectiveness ratios for cetuximab + FOLFOX, panitumumab + FOLFOX and cetuximab + FOLFIRI compared with chemotherapy alone appeared cost-effective at the National Institute for Health and Care Excellence's threshold of £50,000 per quality-adjusted life-year gained, applicable to end-of-life treatments.

Conclusion

Cetuximab and panitumumab were recommended by the National Institute for Health and Care Excellence for patients with previously untreated RAS wild-type metastatic colorectal cancer, not eligible for liver resection at baseline, for use within the National Health Service in England. Both treatments are available via the UK Cancer Drugs Fund.

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Editorial Board/Publication Information

Publication date: February 2018
Source:Injury, Volume 49, Issue 2





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Publication date: February 2018 Source:Injury, Volume 49, Issue 2

Publication date: February 2018
Source:Injury, Volume 49, Issue 2





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Cytomorphologic patterns of Pap and PAS-stained oral exfoliative cytology smears in adult Saudi diabetic patients as compared to healthy controls

Introduction

Diabetes mellitus (DM) is one of the most common metabolic disorders worldwide and 425 million people were estimated to have diabetes by 2017. Oral manifestations reflect the metabolic control of diabetes. Exfoliative cytology using Papanicolaou (Pap) and periodic acid Schiff (PAS) stains is a practical technique to evaluate oral epithelial cytomorphologic changes in diabetes.

Aim

This study analyzes the cytomorphologic changes and the glycogen content in exfoliated oral epithelial cells among diabetic patients as compared to healthy controls using Pap and PAS stains to verify the utility of exfoliative cytology as adjunct to diagnosis, follow up or screening of diabetes.

Subjects and Methods

Eighty-nine participants; 38 adult diabetic patients (case group) and 51 age-matching nondiabetics (control group) were enrolled in the study after fulfilling appropriate inclusion and exclusion criteria. Sampling and staining procedures were performed using routine protocols. Slides were observed by two pathologists and categorized as inflammatory, dyskaryotic and negative. Glycogen content was expressed as PAS negative or +, ++, and +++ positive.

Results

The difference between the diabetics and the controls was statistically significant regarding inflammatory, dyskaryotic/nuclear changes and glycogen content and staining intensity. Other observed finding in diabetic patient smears included binucleation, polychromic, and/or vacuolated cytoplasm.

Conclusions

Cytomorphologic changes of oral epithelial cells reflect the complex pathological mechanisms by which DM affects cellular metabolism and function. Cytomorphologic patterns of Pap and PAS-stained oral exfoliative cytology smears can be helpful for diagnosis, follow up as well as for screening for diabetes in high prevalence communities.

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Cytological investigation of a first case of basal cell adenocarcinoma arising in the minor salivary glands. Case report and review of the literature

Basal cell adenocarcinoma (BCAC) of salivary glands is uncommon low-grade malignancy. Only 19 cases of preoperative cytology were reported up to date. We present here a new case of BCAC arising in the minor salivary gland. Tumor was composed of clustered or isolated roundish, dark cells with small and regular nuclei. Chromatin was dusty with small nucleoli. Cytoplasm was gray and scant. Clusters showed typical and characteristic basal architecture with peripheral palisading neighboring eosinophilic basal membranes. A false-negative diagnosis of basal cell adenoma was rendered. In our knowledge it is the first cytological description of BCAC arising in the minor salivary gland.

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Metastatic hepatocellular carcinoma diagnosed by fine needle aspiration: A clinical and cytologic study

Background

Hepatocellular carcinoma (HCC) is the second leading cause of cancer deaths worldwide. The clinical and cytological features of metastatic HCC have not been well established.

Methods

To determine the clinical and cytological features of metastatic HCC, we retrospectively searched for all HCC metastasis diagnosed by fine needle aspiration or core biopsy.

Results

We found 12 bone metastases, 11 intra-abdominal, 4 lung, 3 soft tissue, and 2 lymph node metastases from 32 patients. 7/12 bone metastases were vertebral body, 4 were pelvic bone, and 1 case was humerus. 10/32 cases showed concurrent metastasis at a different location. The average metastasis size was 40.9 mm. Tumor grades of HCC showed near equal distribution. The following cytological features are most frequently associated with metastatic HCC: single tumor cells (88.9%), cytoplasmic vacuolization (70.4%), trabecular pattern (70.4%), bare nuclei (66.7%), prominent nucleoli (66.7%), tumor giant cells (44.4%), and traversing capillaries (44.4%) and encased by endothelium (18.5%). Immunohistochemical stains of 12 cases showed the majority were positive for E-Cadherin, Carcinoembryonic Antigen, and HepPar1. Negativity for CK7 and CK20 is contributory to making the diagnosis.

Conclusion

The most frequent metastatic HCC diagnosed by FNA was from bone, especially the vertebral body. The frequent cytomorphology and immunophenotype seen in primary HCC are good diagnostic criteria for diagnosing metastatic HCC.

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Germinal Centers Determine the Prognostic Relevance of Tertiary Lymphoid Structures and Are Impaired by Corticosteroids in Lung Squamous Cell Carcinoma

In solid tumors, the presence of lymph node–like structures called tertiary lymphoid structures (TLS) is associated with improved patient survival. However, little is known about how TLS develop in cancer, how their function affects survival, and whether they are affected by cancer therapy. In this study, we used multispectral microscopy, quantitative pathology, and gene expression profiling to analyze TLS formation in human lung squamous cell carcinoma (LSCC) and in an experimental model of lung TLS induction. We identified a niche of CXCL13+ perivascular and CXCL12+LTB+ and PD-L1+ epithelial cells supporting TLS formation. We also characterized sequential stages of TLS maturation in LSCC culminating in the formation of germinal centers (GC). In untreated patients, TLS density was the strongest independent prognostic marker. Furthermore, TLS density correlated with GC formation and expression of adaptive immune response–related genes. In patients treated with neoadjuvant chemotherapy, TLS density was similar, but GC formation was impaired and the prognostic value of TLS density was lost. Corticosteroids are coadministered with chemotherapy to manage side effects in LSCC patients, so we evaluated whether they impaired TLS development independently of chemotherapy. TLS density and GC formation were each reduced in chemotherapy-naïve LSCC patients treated with corticosteroids before surgery, compared with untreated patients, a finding that we confirmed in the experimental model of lung TLS induction. Overall, our results highlight the importance of GC formation in TLS during tumor development and treatment.Significance: Corticosteroid treatment during chemotherapy negatively affects the development of tertiary lymphoid structures and abrogates their prognostic value in patients with lung cancer. Cancer Res; 78(5); 1308–20. ©2018 AACR.

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Therapy-Educated Mesenchymal Stem Cells Enrich for Tumor-Initiating Cells

Stromal cells residing in the tumor microenvironment contribute to the development of therapy resistance. Here we show that chemotherapy-educated mesenchymal stem cells (MSC) promote therapy resistance via cross-talk with tumor-initiating cells (TIC), a resistant tumor cell subset that initiates tumorigenesis and metastasis. In response to gemcitabine chemotherapy, MSCs colonized pancreatic adenocarcinomas in large numbers and resided in close proximity to TICs. Furthermore, gemcitabine-educated MSCs promoted the enrichment of TICs in vitro and enhance tumor growth in vivo. These effects were dependent on the secretion of CXCL10 by gemcitabine-educated MSCs and subsequent activation of the CXCL10–CXCR3 axis in TICs. In an orthotopic pancreatic tumor model, targeting TICs using nanovesicles (called nanoghosts) derived from MSC membranes and loaded with a CXCR3 antagonist enhanced therapy outcome and delayed tumor regrowth when administered in combination with gemcitabine. Overall, our results establish a mechanism through which MSCs promote chemoresistance, and propose a novel drug delivery system to target TICs and overcome this resistance.Significance: These results establish a mechanism by which mesenchyme stem cells in the tumor microenvironment promote chemoresistance, and they propose a novel drug delivery system to overcome this challenge. Cancer Res; 78(5); 1253–65. ©2018 AACR.

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A KDM5 Inhibitor Increases Global H3K4 Trimethylation Occupancy and Enhances the Biological Efficacy of 5-Aza-2'-Deoxycytidine

The H3K4 demethylase KDM5B is amplified and overexpressed in luminal breast cancer, suggesting it might constitute a potential cancer therapy target. Here, we characterize, in breast cancer cells, the molecular effects of a recently developed small-molecule inhibitor of the KDM5 family of proteins (KDM5i), either alone or in combination with the DNA-demethylating agent 5-aza-2′-deoxycytidine (DAC). KDM5i treatment alone increased expression of a small number of genes, whereas combined treatment with DAC enhanced the effects of the latter for increasing expression of hundreds of DAC-responsive genes. ChIP-seq studies revealed that KDM5i resulted in the broadening of existing H3K4me3 peaks. Furthermore, cells treated with the drug combination exhibited increased promoter and gene body H3K4me3 occupancy at DAC-responsive genes compared with DAC alone. Importantly, treatment with either DAC or DAC+KDM5i induced a dramatic increase in H3K27ac at enhancers with an associated significant increase in target gene expression, suggesting a previously unappreciated effect of DAC on transcriptional regulation. KDM5i synergized with DAC to reduce the viability of luminal breast cancer cells in in vitro assays. Our study provides the first look into the molecular effects of a novel KDM5i compound and suggests that combinatorial inhibition along with DAC represents a new area to explore in translational epigenetics.Significance: This study offers a first look into the molecular effects of a novel KDM5 inhibitory compound, suggesting how its use in combination with DNA methylation inhibitors presents new opportunities to explore in translational cancer epigenetics. Cancer Res; 78(5); 1127–39. ©2017 AACR.

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Brain-Mimetic 3D Culture Platforms Allow Investigation of Cooperative Effects of Extracellular Matrix Features on Therapeutic Resistance in Glioblastoma

Glioblastoma (GBM) tumors exhibit potentially actionable genetic alterations against which targeted therapies have been effective in treatment of other cancers. However, these therapies have largely failed in GBM patients. A notable example is kinase inhibitors of EGFR, which display poor clinical efficacy despite overexpression and/or mutation of EGFR in >50% of GBM. In addressing this issue, preclinical models may be limited by the inability to accurately replicate pathophysiologic interactions of GBM cells with unique aspects of the brain extracellular matrix (ECM), which is relatively enriched in hyaluronic acid (HA) and flexible. In this study, we present a brain-mimetic biomaterial ECM platform for 3D culturing of patient-derived GBM cells, with improved pathophysiologic properties as an experimental model. Compared with orthotopic xenograft assays, the novel biomaterial cultures we developed better preserved the physiology and kinetics of acquired resistance to the EGFR inhibition than gliomasphere cultures. Orthogonal modulation of both HA content and mechanical properties of biomaterial scaffolds was required to achieve this result. Overall, our findings show how specific interactions between GBM cell receptors and scaffold components contribute significantly to resistance to the cytotoxic effects of EGFR inhibition.Significance: Three-dimensional culture scaffolds of glioblastoma provide a better physiological representation over current methods of patient-derived cell culture and xenograft models. Cancer Res; 78(5); 1358–70. ©2017 AACR.

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Race Disparities in the Contribution of miRNA Isoforms and tRNA-Derived Fragments to Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) is a breast cancer subtype characterized by marked differences between White and Black/African-American women. We performed a systems-level analysis on datasets from The Cancer Genome Atlas to elucidate how the expression patterns of mRNAs are shaped by regulatory noncoding RNAs (ncRNA). Specifically, we studied isomiRs, that is, isoforms of miRNAs, and tRNA-derived fragments (tRF). In normal breast tissue, we observed a marked cohesiveness in both the ncRNA and mRNA layers and the associations between them. This cohesiveness was widely disrupted in TNBC. Many mRNAs become either differentially expressed or differentially wired between normal breast and TNBC in tandem with isomiR or tRF dysregulation. The affected pathways included energy metabolism, cell signaling, and immune responses. Within TNBC, the wiring of the affected pathways with isomiRs and tRFs differed in each race. Multiple isomiRs and tRFs arising from specific miRNA loci (e.g., miR-200c, miR-21, the miR-17/92 cluster, the miR-183/96/182 cluster) and from specific tRNA loci (e.g., the nuclear tRNAGly and tRNALeu, the mitochondrial tRNAVal and tRNAPro) were strongly associated with the observed race disparities in TNBC. We highlight the race-specific aspects of transcriptome wiring by discussing in detail the metastasis-related MAPK and the Wnt/β-catenin signaling pathways, two of the many key pathways that were found differentially wired. In conclusion, by employing a data- and knowledge-driven approach, we comprehensively analyzed the normal and cancer transcriptomes to uncover novel key contributors to the race-based disparities of TNBC.Significance: This big data-driven study comparing normal and cancer transcriptomes uncovers RNA expression differences between Caucasian and African-American patients with triple-negative breast cancer that might help explain disparities in incidence and aggressive character. Cancer Res; 78(5); 1140–54. ©2017 AACR.

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GADD45{beta} Loss Ablates Innate Immunosuppression in Cancer

T-cell exclusion from the tumor microenvironment (TME) is a major barrier to overcoming immune escape. Here, we identify a myeloid-intrinsic mechanism governed by the NF-κB effector molecule GADD45β that restricts tumor-associated inflammation and T-cell trafficking into tumors. In various models of solid cancers refractory to immunotherapies, including hepatocellular carcinoma and ovarian adenocarcinoma, Gadd45b inhibition in myeloid cells restored activation of proinflammatory tumor-associated macrophages (TAM) and intratumoral immune infiltration, thereby diminishing oncogenesis. Our results provide a basis to interpret clinical evidence that elevated expression of GADD45B confers poor clinical outcomes in most human cancers. Furthermore, they suggest a therapeutic target in GADD45β for reprogramming TAM to overcome immunosuppression and T-cell exclusion from the TME.Significance: These findings define a myeloid-based immune checkpoint that restricts T-cell trafficking into tumors, with potentially important therapeutic implications to generally improve the efficacy of cancer immunotherapy. Cancer Res; 78(5); 1275–92. ©2017 AACR.

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Loss of RASSF4 Expression in Multiple Myeloma Promotes RAS-Driven Malignant Progression

RAS mutations occur frequently in multiple myeloma (MM), but apart from driving progression, they can also stimulate antitumor effects by activating tumor-suppressive RASSF proteins. Although this family of death effector molecules are often silenced in cancers, functional data about RASSF proteins in MM are lacking. Here, we report that RASSF4 is downregulated during MM progression and correlates with a poor prognosis. Promoter methylation analysis in human cell lines revealed an inverse correlation between RASSF4 mRNA levels and methylation status. Epigenetic modulating agents restored RASSF4 expression. Enforced expression of RASSF4 induced G2-phase cell-cycle arrest and apoptosis in human cell lines, reduced primary MM cell viability, and blocked MM growth in vivo. Mechanistic investigations showed that RASSF4 linked RAS to several pro-death pathways, including those regulated by the kinases MST1, JNK, and p38. By activating MST1 and the JNK/c-Jun pathway, RASSF4 sensitized MM cells to bortezomib. Genetic or pharmacological elevation of RASSF4 levels increased the anti-MM effects of the clinical relevant MEK1/2 inhibitor trametinib. Kinome analysis revealed that this effect was mediated by concomitant activation of the JNK/c-Jun pathway along with inactivation of the MEK/ERK and PI3K/mTOR/Akt pathways. Overall, our findings establish RASSF4 as a tumor-suppressive hub in MM and provide a mechanistic rationale for combining trametinib with HDAC inhibitors or bortezomib to treat patients with tumors exhibiting low RASSF4 expression.Significance: These findings provide a mechanistic rationale for combining trametinib with HDAC inhibitors or bortezomib in patients with multiple myeloma whose tumors exhibit low RASSF4 expression. Cancer Res; 78(5); 1155–68. ©2017 AACR.

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Combined Mutation of Apc, Kras, and Tgfbr2 Effectively Drives Metastasis of Intestinal Cancer

Colorectal cancer is driven by the accumulation of driver mutations, but the contributions of specific mutations to different steps in malignant progression are not fully understood. In this study, we generated mouse models harboring different combinations of key colorectal cancer driver mutations (Apc, Kras, Tgfbr2, Trp53, Fbxw7) in intestinal epithelial cells to comprehensively investigate their roles in the development of primary tumors and metastases. ApcΔ716 mutation caused intestinal adenomas and combination with Trp53R270H mutation or Tgfbr2 deletion induced submucosal invasion. The addition of KrasG12D mutation yielded epithelial–mesenchymal transition (EMT)-like morphology and lymph vessel intravasation of the invasive tumors. In contrast, combinations of ApcΔ716 with KrasG12D and Fbxw7 mutation were insufficient for submucosal invasion, but still induced EMT-like histology. Studies using tumor-derived organoids showed that KrasG12D was critical for liver metastasis following splenic transplantation, when this mutation was combined with either ApcΔ716 plus Trp53R270H or Tgfbr2 deletion, with the highest incidence of metastasis displayed by tumors with a ApcΔ716 KrasG12D Tgfbr2−/− genotype. RNA sequencing analysis of tumor organoids defined distinct gene expression profiles characteristic for the respective combinations of driver mutations, with upregulated genes in ApcΔ716 KrasG12D Tgfbr2−/− tumors found to be similarly upregulated in specimens of human metastatic colorectal cancer. Our results show how activation of Wnt and Kras with suppression of TGFβ signaling in intestinal epithelial cells is sufficient for colorectal cancer metastasis, with possible implications for the development of metastasis prevention strategies.Significance: These findings illuminate how key driver mutations in colon cancer cooperate to drive the development of metastatic disease, with potential implications for the development of suitable prevention strategies. Cancer Res; 78(5); 1334–46. ©2017 AACR.

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Long Noncoding RNA pancEts-1 Promotes Neuroblastoma Progression through hnRNPK-Mediated {beta}-Catenin Stabilization

Long noncoding RNAs (lncRNA) play essential roles in tumor progression. However, the functions of lncRNAs in the tumorigenesis and aggressiveness of neuroblastoma still remain to be determined. Here, we report the identification of lncRNA pancEts-1 as a novel driver of neuroblastoma progression by using a public microarray dataset. LncRNA pancEts-1 promoted the growth, invasion, and metastasis of neuroblastoma cells in vitro and in vivo. Mechanistically, pancEts-1 bound to hnRNPK to facilitate its physical interaction with β-catenin, whereas hnRNPK stabilized the β-catenin by inhibiting proteasome-mediated degradation, resulting in transcriptional alteration of target genes associated with neuroblastoma progression. Both pancEts-1 and hnRNPK were upregulated in clinical neuroblastoma tissues, and were associated with unfavorable outcome of patients. Overall, our results define an oncogenic role of pancEts-1 in neuroblastoma progression through hnRNPK-mediated β-catenin stabilization, with potential implications for the clinical therapeutics of neuroblastoma.Significance: These findings reveal the oncogenic functions of a long noncoding RNA in neuroblastoma progression, offering a potential target for clinical therapeutics. Cancer Res; 78(5); 1169–83. ©2018 AACR.

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Highlights from Recent Cancer Literature

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FIH Is an Oxygen Sensor in Ovarian Cancer for G9a/GLP-Driven Epigenetic Regulation of Metastasis-Related Genes

The prolyl hydroxylase domain-containing proteins (PHD1-3) and the asparaginyl hydroxlyase factor inhibiting HIF (FIH) are oxygen sensors for hypoxia-inducible factor-driven transcription of hypoxia-induced genes, but whether these sensors affect oxygen-dependent epigenetic regulation more broadly is not known. Here, we show that FIH exerts an additional role as an oxygen sensor in epigenetic control by the histone lysine methyltransferases G9a and GLP. FIH hydroxylated and inhibited G9a and GLP under normoxia. When the FIH reaction was limited under hypoxia, G9a and GLP were activated and repressed metastasis suppressor genes, thereby triggering cancer cell migration and peritoneal dissemination of ovarian cancer xenografts. In clinical specimens of ovarian cancer, expression of FIH and G9a were reciprocally associated with patient outcomes. We also identified mutations of FIH target motifs in G9a and GLP, which exhibited excessive H3K9 methylation and facilitated cell invasion. This study provides insight into a new function of FIH as an upstream regulator of oxygen-dependent chromatin remodeling. It also implies that the FIH-G9a/GLP pathway could be a potential target for inhibiting hypoxia-induced cancer metastasis.Significance: These findings deepen understanding of oxygen-dependent gene regulation and cancer metastasis in response to hypoxia. Cancer Res; 78(5); 1184–99. ©2017 AACR.

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Deletion of the von Hippel-Lindau Gene in Hemangioblasts Causes Hemangioblastoma-like Lesions in Murine Retina

von Hippel-Lindau (VHL) disease is an autosomal-dominant tumor predisposition syndrome characterized by the development of highly vascularized tumors and cysts. LOH of the VHL gene results in aberrant upregulation of hypoxia-inducible factors (HIF) and has been associated with tumor formation. Hemangioblastomas of the central nervous system and retina represent the most prevalent VHL-associated tumors, but no VHL animal model has reproduced retinal capillary hemangioblastomas (RCH), the hallmark lesion of ocular VHL. Here we report our work in developing a murine model of VHL-associated RCH by conditionally inactivating Vhl in a hemangioblast population using a Scl-Cre-ERT2 transgenic mouse line. In transgenic mice carrying the conditional allele and the Scl-Cre-ERT2 allele, 64% exhibited various retinal vascular anomalies following tamoxifen induction. Affected Vhl-mutant mice demonstrated retinal vascular lesions associated with prominent vasculature, anomalous capillary networks, hemorrhage, exudates, and localized fibrosis. Histologic analyses showed RCH-like lesions characterized by tortuous, dilated vasculature surrounded by "tumorlet" cell cluster and isolated foamy stromal cells, which are typically associated with RCH. Fluorescein angiography suggested increased vascular permeability of the irregular retinal vasculature and hemangioblastoma-like lesions. Vhl deletion was detected in "tumorlet" cells via microdissection. Our findings provide a phenotypic recapitulation of VHL-associated RCH in a murine model that may be useful to study RCH pathogenesis and therapeutics aimed at treating ocular VHL.Significance: This study describes a model that phenotypically recapitulates a form of retinal pathogenesis that is driven by genetic loss of the VHL tumor suppressor, providing a useful tool for its study and therapeutic intervention. Cancer Res; 78(5); 1266–74. ©2018 AACR.

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Familial and Somatic BAP1 Mutations Inactivate ASXL1/2-Mediated Allosteric Regulation of BAP1 Deubiquitinase by Targeting Multiple Independent Domains

Deleterious mutations of the ubiquitin carboxy-terminal hydrolase BAP1 found in cancers are predicted to encode inactive truncated proteins, suggesting that loss of enzyme function is a primary tumorigenic mechanism. However, many tumors exhibit missense mutations or in-frame deletions or insertions, often outside the functionally critical UCH domain in this tumor suppressor protein. Thus, precisely how these mutations inactivate BAP1 is unknown. Here, we show how these mutations affect BAP1 interactions with the Polycomb group-like protein, ASXL2, using combinations of computational modeling technology, molecular biology, and in vitro reconstitution biochemistry. We found that the BAP1–ASXL2 interaction is direct and high affinity, occurring through the ASXH domain of ASXL2, an obligate partner for BAP1 enzymatic activity. The ASXH domain was the minimal domain for binding the BAP1 ULD domain, and mutations on the surfaces of predicted helices of ASXH abolished BAP1 association and stimulation of BAP1 enzymatic activity. The BAP1-UCH, BAP1-ULD, and ASXH domains formed a cooperative stable ternary complex required for deubiquitination. We defined four classes of alterations in BAP1 outside the UCH domain, each failing to productively recruit ASXH to the wild-type BAP1 catalytic site via the ULD, resulting in loss of BAP1 ubiquitin hydrolase activity. Our results indicate that many BAP1 mutations act allosterically to inhibit ASXH binding, thereby leading to loss of enzyme activity. Small-molecule approaches to reactivate latent wild-type UCH activity of these mutants might be therapeutically viable.Significance: Combined computational and biochemical approaches demonstrate that the BAP1–ASXL2 interaction is direct and high affinity and that many BAP1 mutations act allosterically to inhibit BAP1–ASXL2 binding. Cancer Res; 78(5); 1200–13. ©2017 AACR.

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Inflammasome Adaptor ASC Suppresses Apoptosis of Gastric Cancer Cells by an IL18-Mediated Inflammation-Independent Mechanism

Inflammasomes are key regulators of innate immunity in chronic inflammatory disorders and autoimmune diseases, but their role in inflammation-associated tumorigenesis remains ill-defined. Here we reveal a protumorigenic role in gastric cancer for the key inflammasome adaptor apoptosis-related speck-like protein containing a CARD (ASC) and its effector cytokine IL18. Genetic ablation of ASC in the gp130F/F spontaneous mouse model of intestinal-type gastric cancer suppressed tumorigenesis by augmenting caspase-8-like apoptosis in the gastric epithelium, independently from effects on myeloid cells and mucosal inflammation. This phenotype was characterized by reduced activation of caspase-1 and NF-κB activation and reduced expression of mature IL18, but not IL1β, in gastric tumors. Genetic ablation of IL18 in the same model also suppressed gastric tumorigenesis, whereas blockade of IL1β and IL1α activity upon genetic ablation of the IL1 receptor had no effect. The specific protumorigenic role for IL18 was associated with high IL18 gene expression in the gastric tumor epithelium compared with IL1β, which was preferentially expressed in immune cells. Supporting an epithelial-specific role for IL18, we found it to be highly secreted from human gastric cancer cell lines. Moreover, IL18 blockade either by a neutralizing anti-IL18 antibody or by CRISPR/Cas9-driven deletion of ASC augmented apoptosis in human gastric cancer cells. In clinical specimens of human gastric cancer tumors, we observed a significant positive correlation between elevated mature IL18 protein and ASC mRNA levels. Collectively, our findings reveal the ASC/IL18 signaling axis as a candidate therapeutic target in gastric cancer.Significance: Inflammasome activation that elevates IL18 helps drive gastric cancer by protecting cancer cells against apoptosis, with potential implications for new therapeutic strategies in this setting. Cancer Res; 78(5); 1293–307. ©2017 AACR.

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O-GlcNAcylation of the Tumor Suppressor FOXO3 Triggers Aberrant Cancer Cell Growth

Posttranslational modifications of tumor suppressors can induce abnormal cell growth. Here, we identify site-specific O-GlcNAcylation as a critical block of FOXO3 that may abrogate a part of the p53 pathway, resulting in aberrant cancer cell growth. Of seven O-GlcNAcylation sites identified within the FOXO3 transactivation domain, we found that changes in O-GlcNAcylation at Ser284 modulated p21-mediated cancer cell growth. Overexpression of either O-GlcNAcylated FOXO3 (FOX-OV) or a Ser-to-Ala mutant (S284A) in PANC-1 cells indicated that S284 O-GlcNAc acts as a critical block of the FOXO tumor suppressor and induces proliferation in PANC-1 cancer cells by stimulating the MDM2-p53-p21 axis. Furthermore, S284A mutant cells lacking S284 O-GlcNAc and FOX-OV cells exhibited opposing MDM2-p53-p21 axis expression patterns at both the mRNA and protein levels. Thus, our study provides evidence to support a role for S284 O-GlcNAc as a critical block of FOXO3 to induce subsequent cancer cell growth via abrogation of the p53 regulatory circuit.Significance: These findings highlight a posttranslational mechanism for indirect abrogation of the p53 pathway, one that may occur with some frequency in human cancer cells. Cancer Res; 78(5); 1214–24. ©2018 AACR.

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Inactivation of Cancer-Associated-Fibroblasts Disrupts Oncogenic Signaling in Pancreatic Cancer Cells and Promotes Its Regression

Resident fibroblasts that contact tumor epithelial cells (TEC) can become irreversibly activated as cancer-associated-fibroblasts (CAF) that stimulate oncogenic signaling in TEC. In this study, we evaluated the cross-talk between CAF and TEC isolated from tumors generated in a mouse model of KRAS/mut p53-induced pancreatic cancer (KPC mice). Transcriptomic profiling conducted after treatment with the anticancer compound Minnelide revealed deregulation of the TGFβ signaling pathway in CAF, resulting in an apparent reversal of their activated state to a quiescent, nonproliferative state. TEC exposed to media conditioned by drug-treated CAFs exhibited a decrease in oncogenic signaling, as manifested by downregulation of the transcription factor Sp1. This inhibition was rescued by treating TEC with TGFβ. Given promising early clinical studies with Minnelide, our findings suggest that approaches to inactivate CAF and prevent tumor–stroma cross-talk may offer a viable strategy to treat pancreatic cancer.Significance: In an established mouse model of pancreatic cancer, administration of the promising experimental drug Minnelide was found to actively deplete reactive stromal fibroblasts and to trigger tumor regression, with implications for stromal-based strategies to attack this disease. Cancer Res; 78(5); 1321–33. ©2018 AACR.

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The CARMA3-Bcl10-MALT1 Signalosome Drives NF{kappa}B Activation and Promotes Aggressiveness in Angiotensin II Receptor-Positive Breast Cancer

The angiotensin II receptor AGTR1, which mediates vasoconstrictive and inflammatory signaling in vascular disease, is overexpressed aberrantly in some breast cancers. In this study, we established the significance of an AGTR1-responsive NFκB signaling pathway in this breast cancer subset. We documented that AGTR1 overexpression occurred in the luminal A and B subtypes of breast cancer, was mutually exclusive of HER2 expression, and correlated with aggressive features that include increased lymph node metastasis, reduced responsiveness to neoadjuvant therapy, and reduced overall survival. Mechanistically, AGTR1 overexpression directed both ligand-independent and ligand-dependent activation of NFκB, mediated by a signaling pathway that requires the triad of CARMA3, Bcl10, and MALT1 (CBM signalosome). Activation of this pathway drove cancer cell–intrinsic responses that include proliferation, migration, and invasion. In addition, CBM-dependent activation of NFκB elicited cancer cell–extrinsic effects, impacting endothelial cells of the tumor microenvironment to promote tumor angiogenesis. CBM/NFκB signaling in AGTR1+ breast cancer therefore conspires to promote aggressive behavior through pleiotropic effects. Overall, our results point to the prognostic and therapeutic value of identifying AGTR1 overexpression in a subset of HER2-negative breast cancers, and they provide a mechanistic rationale to explore the repurposing of drugs that target angiotensin II–dependent NFκB signaling pathways to improve the treatment of this breast cancer subset.Significance: These findings offer a mechanistic rationale to explore the repurposing of drugs that target angiotensin action to improve the treatment of AGTR1-expressing breast cancers. Cancer Res; 78(5); 1225–40. ©2017 AACR.

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Statin-Induced Cancer Cell Death Can Be Mechanistically Uncoupled from Prenylation of RAS Family Proteins

The statin family of drugs preferentially triggers tumor cell apoptosis by depleting mevalonate pathway metabolites farnesyl pyrophosphate (FPP) and geranylgeranyl pyrophosphate (GGPP), which are used for protein prenylation, including the oncoproteins of the RAS superfamily. However, accumulating data indicate that activation of the RAS superfamily are poor biomarkers of statin sensitivity, and the mechanism of statin-induced tumor-specific apoptosis remains unclear. Here we demonstrate that cancer cell death triggered by statins can be uncoupled from prenylation of the RAS superfamily of oncoproteins. Ectopic expression of different members of the RAS superfamily did not uniformly sensitize cells to fluvastatin, indicating that increased cellular demand for protein prenylation cannot explain increased statin sensitivity. Although ectopic expression of HRAS increased statin sensitivity, expression of myristoylated HRAS did not rescue this effect. HRAS-induced epithelial-to-mesenchymal transition (EMT) through activation of zinc finger E-box binding homeobox 1 (ZEB1) sensitized tumor cells to the antiproliferative activity of statins, and induction of EMT by ZEB1 was sufficient to phenocopy the increase in fluvastatin sensitivity; knocking out ZEB1 reversed this effect. Publicly available gene expression and statin sensitivity data indicated that enrichment of EMT features was associated with increased sensitivity to statins in a large panel of cancer cell lines across multiple cancer types. These results indicate that the anticancer effect of statins is independent from prenylation of RAS family proteins and is associated with a cancer cell EMT phenotype.Significance: The use of statins to target cancer cell EMT may be useful as a therapy to block cancer progression. Cancer Res; 78(5); 1347–57. ©2017 AACR.

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Nkx2.8 Inhibits Epithelial-Mesenchymal Transition in Bladder Urothelial Carcinoma via Transcriptional Repression of Twist1

Epithelial-to-mesenchymal transition (EMT) promotes metastasis, which is the main cause of bladder urothelial carcinoma–related death. Loss of the candidate tumor-suppressor gene Nkx2.8 has been associated with urothelial carcinoma lymph node metastasis. Here, we show that enforced expression of Nkx2.8 is sufficient to inhibit EMT, reduce motility, and blunt invasiveness of urothelial carcinoma cells. Mechanistic investigations showed that Nkx2.8 negatively regulated expression of the EMT inducer Twist1 in urothelial carcinoma cells, at both the level of mRNA and protein accumulation. Nkx2.8 bound directly to the promoter region of this gene and transcriptionally repressed its expression. Twist1 upregulation reversed EMT inhibition by Nkx2.8, restoring the invasive phenotype of urothelial carcinoma cells. In clinical urothelial carcinoma specimens, expression of Nkx2.8 inversely correlated with Twist1 expression, and urothelial carcinoma patients with Nkx2.8 positivity and low Twist1 expression displayed the best prognosis. Our findings highlight the Nkx2.8–Twist1 axis as candidate target for therapeutic intervention in advanced urothelial carcinoma.Significance: These findings highlight a novel EMT signaling axis as a candidate target for therapeutic intervention in advanced urothelial carcinomas. Cancer Res; 78(5); 1241–52. ©2018 AACR.

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Correction: KLF6 Suppresses Metastasis of Clear Cell Renal Cell Carcinoma via Transcriptional Repression of E2F1

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ATP increases [Ca2+]i and activates a Ca2+-dependent Cl− current in rat ventricular fibroblasts

Key Points

• Fibroblasts isolated from adult rat ventricles consistently respond to (5–100 μM) ATP.
• ATP, ADP, and UTP all elicit similar dose-dependent increases in [Ca²⁺]_i.
• ATP also activates an outwardly rectifying Cl⁻ current; in contrast, ADP and UTP have much smaller electrophysiological effects.
• This ATP-dependent Cl⁻ current is markedly reduced when: i) [Ca²⁺]_i is buffered with BAPTA, or ii) the intrinsic phospholipase C activity in these fibroblasts is inhibited.
• PCR analysis suggests that the ATP-induced current is generated by the Ca²⁺-activated Cl⁻ current transcript TMEM 16F, also denoted ANO6.
• These findings reveal new physiological and pharmacological principles that regulate ventricular fibroblast function.

 

New Findings

• What is the central question of this study?

  Although electrophysiological and biophysical characteristics of heart fibroblasts have been studied in detail, their responses to prominent paracrine agents in the myocardium have not been adequately addressed. Our experiments characterize changes in cellular electrophysiology and intracellular calcium in response to ATP.

• What is the main finding and its importance?

  In rat ventricular fibroblasts maintained in cell culture we find that ATP activates a specific subset of Ca²⁺-activated Cl⁻ channels as a consequence of binding to P2Y purinoceptors and then activating phospholipase C. This response is not dependent on [Ca²⁺]_o but requires an increase in [Ca²⁺]_i and is modulated by the type of nucleotide that is the purinergic agonist.

Abstract

Effects of adenosine 5′-triphosphate (ATP) on enzymatically isolated rat ventricular fibroblasts maintained in short-term (36–72 hrs) cell culture were examined. Immunocytochemical staining of these cells revealed that a fibroblast, as opposed to a myofibroblast, phenotype was predominant. ATP, ADP or UTP all produced large increases in intracellular Ca²⁺ [Ca²⁺]_i. Voltage-clamp studies (amphotericin-perforated patch) showed that ATP (1–100 μM) activated an outwardly rectifying current, having a reversal potential very close to the Nernst potential for Cl⁻. In contrast, ADP was much less effective and UTP produced no detectable current. The nonselective Cl⁻ channel blockers niflumic acid, DIDS and NPPB (each at 100 μM), blocked the responses to 100 μM ATP. 2-MTATP, an agonist for P2Y purinoceptors activated a very similar outwardly rectifying C1⁻ current. The P2Y receptor antagonists, suramin and PPADS (100 μM each), significantly inhibited the Cl⁻ current produced by 100 μM ATP. ATP was able to activate this Cl⁻ current when [Ca²⁺]_o was removed, but not when [Ca²⁺]_i was buffered with BAPTA-AM. In the presence of the phospholipase C (PLC) inhibitor U73122, this Cl⁻ current could not be activated. PCR analysis revealed strong signals for a number of P2Y purinoceptors; and also for the Ca²⁺-activated Cl⁻ channel, TMEM 16F (also denoted ANO-6). In summary, these results demonstrate that activation of P2Y receptors by ATP causes a PLC-dependent increase in [Ca²⁺]_i, followed by activation of a Ca²⁺-dependent Cl⁻ current in rat ventricular fibroblasts.

This article is protected by copyright. All rights reserved

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Novel BAFF-Receptor Antibody to Natively Folded Recombinant Protein Eliminates Drug-Resistant Human B-cell Malignancies In Vivo

Purpose: mAbs such as anti-CD20 rituximab are proven therapies in B-cell malignancies, yet many patients develop resistance. Novel therapies against alternative targets are needed to circumvent resistance mechanisms. We sought to generate mAbs against human B-cell–activating factor receptor (BAFF-R/TNFRSF13C), which has not yet been targeted successfully for cancer therapy.

Experimental Design: Novel mAbs were generated against BAFF-R, expressed as a natively folded cell surface immunogen on mouse fibroblast cells. Chimeric BAFF-R mAbs were developed and assessed for in vitro and in vivo monotherapy cytotoxicity. The chimeric mAbs were tested against human B-cell tumor lines, primary patient samples, and drug-resistant tumors.

Results: Chimeric antibodies bound with high affinity to multiple human malignant B-cell lines and induced potent antibody-dependent cellular cytotoxicity (ADCC) against multiple subtypes of human lymphoma and leukemia, including primary tumors from patients who had relapsed after anti-CD20 therapy. Chimeric antibodies also induced ADCC against ibrutinib-resistant and rituximab-insensitive CD20-deficient variant lymphomas, respectively. Importantly, they demonstrated remarkable in vivo growth inhibition of drug-resistant tumor models in immunodeficient mice.

Conclusions: Our method generated novel anti–BAFF-R antibody therapeutics with remarkable single-agent antitumor effects. We propose that these antibodies represent an effective new strategy for targeting and treating drug-resistant B-cell malignancies and warrant further development. Clin Cancer Res; 24(5); 1114–23. ©2017 AACR.

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Tumor Side as Model of Integrative Molecular Classification of Colorectal Cancer

It has long since been recognized that colorectal cancer is molecularly heterogeneous and its clinical behavior differs if the primary tumor was located in the right or left side of the colon. Recent studies have shown that part of this heterogeneity is captured by the anatomic location of the tumor. Clin Cancer Res; 24(5); 989–90. ©2017 AACR.

See related article by Loree et al., p. 1062

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t-Darpp Activates IGF-1R Signaling to Regulate Glucose Metabolism in Trastuzumab-Resistant Breast Cancer Cells

Purpose: Increased glycolysis and glucose dependence is a hallmark of malignancy that enables tumors to maximize cell proliferation. In HER2⁺ cancers, an increase in glycolytic capacity is associated with trastuzumab resistance. IGF-1R activation and t-Darpp overexpression both confer trastuzumab resistance in breast cancer. We therefore investigated a role for IGF-1R and t-Darpp in regulating glycolytic capacity in HER2⁺ breast cancers.

Experimental Design: We examined the relationship between t-Darpp and IGF-1R expression in breast tumors and their respective relationships with patient survival. To assess t-Darpp's metabolic effects, we used the Seahorse flux analyzer to measure glucose metabolism in trastuzumab-resistant SK-BR-3 cells (SK.Her^R) that have high endogenous t-Darpp levels and SK.tDrp cells that stably overexpress exogenous t-Darpp. To investigate t-Darpp's mechanism of action, we evaluated t-Darpp:IGF-1R complexes by coimmunoprecipitation and proximity ligation assays. We used pathway-specific inhibitors to study the dependence of t-Darpp effects on IGF-1R signaling. We used siRNA knockdown to determine whether glucose reliance in SK.Her^R cells was mediated by t-Darpp.

Results: In breast tumors, PPP1R1B mRNA levels were inversely correlated with IGF-1R mRNA levels and directly associated with shorter overall survival. t-Darpp overexpression was sufficient to increase glucose metabolism in SK.tDrp cells and essential for the glycolytic phenotype of SK.Her^R cells. Recombinant t-Darpp stimulated glucose uptake, glycolysis, and IGF-1R–Akt signaling in SK-BR-3 cells. Finally, t-Darpp stimulated IGF-1R heterodimerization with ErbB receptors and required IGF-1R signaling to confer its metabolic effects.

Conclusions: t-Darpp activates IGF-1R signaling through heterodimerization with EGFR and HER2 to stimulate glycolysis and confer trastuzumab resistance. Clin Cancer Res; 24(5); 1216–26. ©2017 AACR.

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Immunotherapy of Myelodysplastic Syndrome: You Can Run, but You Can't Hide

The hypomethylating agent decitabine induces expression of the cancer/testis antigen NY-ESO-1 in the myeloid cells of patients with myelodysplastic syndrome (MDS). Patients with MDS treated with decitabine and an NY-ESO-1 vaccine developed NY-ESO-1–specific T-cell responses directed against their abnormal myeloid cells, raising hopes for combinatorial immunotherapy of this disease. Clin Cancer Res; 24(5); 991–3. ©2017 AACR.

See related article by Griffiths et al., p. 1019

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HSP27-Mediated Extracellular and Intracellular Signaling Pathways Synergistically Confer Chemoresistance in Squamous Cell Carcinoma of Tongue

Purpose: Squamous cell carcinoma of tongue (SCCT) is the most common type of oral cavity carcinoma. Chemoresistance in SCCT is common, and the underlying mechanism remains largely unknown. We aimed to identify key molecules and signaling pathways mediating chemoresistance in SCCT.

Experimental Design: Using a proteomic approach, we found that the HSP27 was a potential mediator for chemoresistance in SCCT cells. To further validate this role of HSP27, we performed various mechanistic studies using in vitro and in vivo models as well as serum and tissue samples from SCCT patients.

Results: The HSP27 protein level was significantly increased in the multidrug-resistant SCCT cells and cell culture medium. Both HSP27 knockdown and anti-HSP27 antibody treatment reversed chemoresistance. Inversely, both HSP27 overexpression and recombinant human HSP27 protein treatment enhanced chemoresistance. Moreover, chemotherapy significantly induced HSP27 protein expression in both SCCT cells and their culture medium, as well as in tumor tissues and serum of SCCT patients. HSP27 overexpression predicts a poor outcome for SCCT patients receiving chemotherapy. Mechanically, extracellular HSP27 binds to TLR5 and then activates NF-B signaling to maintain SCCT cell survival. TLR5 knockdown or restored IBα protein level disrupts extracellular HSP27-induced NF-B transactivation and chemoresistance. Moreover, intracellular HSP27 binds to BAX and BIM to repress their translocation to mitochondrion and subsequent cytochrome C release upon chemotherapy, resulting in inhibition of the mitochondrial apoptotic pathway.

Conclusions: HSP27 plays a pivotal role in chemoresistance of SCCT cells via a synergistic extracellular and intracellular signaling. HSP27 may represent a potential biomarker and therapeutic target for precision SCCT treatment. Clin Cancer Res; 24(5); 1163–75. ©2017 AACR.

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Biomarker-Stratified Phase III Clinical Trials: Enhancement with a Subgroup-Focused Sequential Design

Among various design approaches to phase III clinical trials with a predictive biomarker, the marker-stratified all-comers design is advantageous because it allows for establishing the utility of both treatment and biomarker, but it is often criticized for requiring large sample sizes, as the design includes both marker-positive and marker-negative patients. In this article, we propose a simple but flexible subgroup-focused design for marker-stratified trials that allow both sequential assessment across marker-defined subgroups and adaptive subgroup selection while retaining an assessment using the entire patient cohort at the final analysis stage, possibly using established marker-based multiple testing procedures. Numerical evaluations indicate that the proposed marker-stratified design has a robustness property in preserving statistical power for detecting various profiles of treatment effects across the subgroups while effectively reducing the number of randomized patients in the marker-negative subgroup with presumably limited treatment efficacy. In contrast, the traditional all-comers and sequential enrichment designs could suffer from low statistical power for some possible profiles of treatment effects. The latter also needs long study durations and a large number of marker-screened patients. We also provide an application to SWOG S0819, a trial to assess the role of cetuximab in treating non–small cell lung cancers. These evaluations indicate that the proposed subgroup-focused approach can enhance the efficiency of the marker-stratified design for definitive evaluation of treatment and biomarker in phase III clinical trials. Clin Cancer Res; 24(5); 994–1001. ©2017 AACR.

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Acetylsalicylic Acid Governs the Effect of Sorafenib in RAS-Mutant Cancers

Purpose: Identify and characterize novel combinations of sorafenib with anti-inflammatory painkillers to target difficult-to-treat RAS-mutant cancer.

Experimental Design: The cytotoxicity of acetylsalicylic acid (aspirin) in combination with the multikinase inhibitor sorafenib (Nexavar) was assessed in RAS-mutant cell lines in vitro. The underlying mechanism for the increased cytotoxicity was investigated using selective inhibitors and shRNA-mediated gene knockdown. In vitro results were confirmed in RAS-mutant xenograft mouse models in vivo.

Results: The addition of aspirin but not isobutylphenylpropanoic acid (ibruprofen) or celecoxib (Celebrex) significantly increased the in vitro cytotoxicity of sorafenib. Mechanistically, combined exposure resulted in increased BRAF/CRAF dimerization and the simultaneous hyperactivation of the AMPK and ERK pathways. Combining sorafenib with other AMPK activators, such as metformin or A769662, was not sufficient to decrease cell viability due to sole activation of the AMPK pathway. The cytotoxicity of sorafenib and aspirin was blocked by inhibition of the AMPK or ERK pathways through shRNA or via pharmacologic inhibitors of RAF (LY3009120), MEK (trametinib), or AMPK (compound C). The combination was found to be specific for RAS/RAF–mutant cells and had no significant effect in RAS/RAF–wild-type keratinocytes or melanoma cells. In vivo treatment of human xenografts in NSG mice with sorafenib and aspirin significantly reduced tumor volume compared with each single-agent treatment.

Conclusions: Combination sorafenib and aspirin exerts cytotoxicity against RAS/RAF–mutant cells by simultaneously affecting two independent pathways and represents a promising novel strategy for the treatment of RAS-mutant cancers. Clin Cancer Res; 24(5); 1090–102. ©2017 AACR.

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Immunotherapy of Lymphoma and Myeloma: Facts and Hopes

Immune checkpoint blockade has driven a revolution in modern oncology, and robust drug development of immune checkpoint inhibitors is underway in both solid tumors and hematologic malignancies. High response rates to programmed cell death 1 (PD-1) blockade using nivolumab or pembrolizumab in classical Hodgkin lymphoma (cHL) and several variants of non-Hodgkin lymphoma (NHL) revealed an intrinsic biological sensitivity to this approach, and work is ongoing exploring combinations with immune checkpoint inhibitors in both cHL and NHL. There are also preliminary data suggesting antitumor efficacy of PD-1 inhibitors used in combination with immunomodulatory drugs in multiple myeloma, and effects of novel monoclonal antibody therapies on the tumor microenvironment may lead to synergy with checkpoint blockade. Although immune checkpoint inhibitors are generally well tolerated, clinicians must use caution and remain vigilant when treating patients with these agents in order to identify immune-related toxicities and prevent treatment-related morbidity and mortality. Autologous stem cell transplant is a useful tool for treatment of hematologic malignancies and has potential as a platform for use of immune checkpoint inhibitors. An important safety signal has emerged surrounding the risk of graft-versus-host disease associated with use of PD-1 inhibitors before and after allogeneic stem cell transplant. We aim to discuss the facts known to date in the use of immune checkpoint inhibitors for patients with lymphoid malignancies and our hopes for expanding the benefits of immunotherapy to patients in the future. Clin Cancer Res; 24(5); 1002–10. ©2017 AACR.

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Activation of 4-1BB on Liver Myeloid Cells Triggers Hepatitis via an Interleukin-27-Dependent Pathway

Purpose: Agonist antibodies targeting the T-cell costimulatory receptor 4-1BB (CD137) are among the most effective immunotherapeutic agents across preclinical cancer models. In the clinic, however, development of these agents has been hampered by dose-limiting liver toxicity. Lack of knowledge of the mechanisms underlying this toxicity has limited the potential to separate 4-1BB agonist–driven tumor immunity from hepatotoxicity.

Experimental Design: The capacity of 4-1BB agonist antibodies to induce liver toxicity was investigated in immunocompetent mice, with or without coadministration of checkpoint blockade, via (i) measurement of serum transaminase levels, (ii) imaging of liver immune infiltrates, and (iii) qualitative and quantitative assessment of liver myeloid and T cells via flow cytometry. Knockout mice were used to clarify the contribution of specific cell subsets, cytokines, and chemokines.

Results: We find that activation of 4-1BB on liver myeloid cells is essential to initiate hepatitis. Once activated, these cells produce interleukin-27 that is required for liver toxicity. CD8 T cells infiltrate the liver in response to this myeloid activation and mediate tissue damage, triggering transaminase elevation. FoxP3⁺ regulatory T cells limit liver damage, and their removal dramatically exacerbates 4-1BB agonist–induced hepatitis. Coadministration of CTLA-4 blockade ameliorates transaminase elevation, whereas PD-1 blockade exacerbates it. Loss of the chemokine receptor CCR2 blocks 4-1BB agonist hepatitis without diminishing tumor-specific immunity against B16 melanoma.

Conclusions: 4-1BB agonist antibodies trigger hepatitis via activation and expansion of interleukin-27–producing liver Kupffer cells and monocytes. Coadministration of CTLA-4 and/or CCR2 blockade may minimize hepatitis, but yield equal or greater antitumor immunity. Clin Cancer Res; 24(5); 1138–51. ©2018 AACR.

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Ipilimumab plus Lenalidomide after Allogeneic and Autologous Stem Cell Transplantation for Patients with Lymphoid Malignancies

Purpose: Prevention or treatment of relapsed lymphoid malignancies after hematopoietic stem cell transplantation (HSCT) requires novel strategies. We hypothesized that antitumor–cell responses could be enhanced by the addition of lenalidomide to the cytotoxic T-lymphocyte–associated protein 4 inhibitor ipilimumab.

Experimental Design: We conducted a phase II investigator-initiated trial to assess the safety and activity of ipilimumab and lenalidomide in patients with lymphoid malignancies that relapsed after allogeneic HSCT and in high-risk patients after autologous HSCT. Patients received 10 mg of oral lenalidomide daily for 21 days followed by intravenous ipilimumab at 3 mg/kg bodyweight. The regimen was repeated 4 weeks later for a total of four treatments.

Results: We enrolled 17 patients (10 allogeneic and seven autologous transplant recipients). Immune-mediated toxicity was limited to one patient with asymptomatic hypothyroidism and one with dermatitis in the allogeneic and autologous groups, respectively. One allogeneic transplant recipient had a flare of prior GVHD while taking lenalidomide that precluded further treatment. All others finished treatment without GVHD. Four of 10 patients in the allogeneic group had complete responses (three of which were durable at 19+, 21+, and 32+ months), and three had partial responses. The disease in six of seven patients in the autologous group remains in remission. The groups had similar immune responses, including a two- to threefold increase in inducible ICOS⁺CD4⁺FoxP3^– T-cell number.

Conclusions: Our early-phase data suggested that ipilimumab plus lenalidomide is well tolerated after HSCT. Adverse events did not differ significantly between the allogeneic and autologous groups. Clin Cancer Res; 24(5); 1011–8. ©2017 AACR.

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Alteration of the Tumor Stroma Using a Consensus DNA Vaccine Targeting Fibroblast Activation Protein (FAP) Synergizes with Antitumor Vaccine Therapy in Mice

Purpose: Fibroblast activation protein (FAP) is overexpressed in cancer-associated fibroblasts and is an interesting target for cancer immune therapy, with prior studies indicating a potential to affect the tumor stroma. Our aim was to extend this earlier work through the development of a novel FAP immunogen with improved capacity to break tolerance for use in combination with tumor antigen vaccines.

Experimental Design: We used a synthetic consensus (SynCon) sequence approach to provide MHC class II help to support breaking of tolerance. We evaluated immune responses and antitumor activity of this novel FAP vaccine in preclinical studies, and correlated these findings to patient data.

Results: This SynCon FAP DNA vaccine was capable of breaking tolerance and inducing both CD8⁺ and CD4⁺ immune responses. In genetically diverse, outbred mice, the SynCon FAP DNA vaccine was superior at breaking tolerance compared with a native mouse FAP immunogen. In several tumor models, the SynCon FAP DNA vaccine synergized with other tumor antigen–specific DNA vaccines to enhance antitumor immunity. Evaluation of the tumor microenvironment showed increased CD8⁺ T-cell infiltration and a decreased macrophage infiltration driven by FAP immunization. We extended this to patient data from The Cancer Genome Atlas, where we find high FAP expression correlates with high macrophage and low CD8⁺ T-cell infiltration.

Conclusions: These results suggest that immune therapy targeting tumor antigens in combination with a microconsensus FAP vaccine provides two-fisted punch-inducing responses that target both the tumor microenvironment and tumor cells directly. Clin Cancer Res; 24(5); 1190–201. ©2018 AACR.

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NY-ESO-1 Vaccination in Combination with Decitabine Induces Antigen-Specific T-lymphocyte Responses in Patients with Myelodysplastic Syndrome

Purpose: Treatment options are limited for patients with high-risk myelodysplastic syndrome (MDS). The azanucleosides, azacitidine and decitabine, are first-line therapy for MDS that induce promoter demethylation and gene expression of the highly immunogenic tumor antigen NY-ESO-1. We demonstrated that patients with acute myeloid leukemia (AML) receiving decitabine exhibit induction of NY-ESO-1 expression in circulating blasts. We hypothesized that vaccinating against NY-ESO-1 in patients with MDS receiving decitabine would capitalize upon induced NY-ESO-1 expression in malignant myeloid cells to provoke an NY-ESO-1–specific MDS-directed cytotoxic T-cell immune response.

Experimental Design: In a phase I study, 9 patients with MDS received an HLA-unrestricted NY-ESO-1 vaccine (CDX-1401 + poly-ICLC) in a nonoverlapping schedule every four weeks with standard-dose decitabine.

Results: Analysis of samples serially obtained from the 7 patients who reached the end of the study demonstrated induction of NY-ESO-1 expression in 7 of 7 patients and NY-ESO-1–specific CD4⁺ and CD8⁺ T-lymphocyte responses in 6 of 7 and 4 of 7 of the vaccinated patients, respectively. Myeloid cells expressing NY-ESO-1, isolated from a patient at different time points during decitabine therapy, were capable of activating a cytotoxic response from autologous NY-ESO-1–specific T lymphocytes. Vaccine responses were associated with a detectable population of CD141^Hi conventional dendritic cells, which are critical for the uptake of NY-ESO-1 vaccine and have a recognized role in antitumor immune responses.

Conclusions: These data indicate that vaccination against induced NY-ESO-1 expression can produce an antigen-specific immune response in a relatively nonimmunogenic myeloid cancer and highlight the potential for induced antigen-directed immunotherapy in a group of patients with limited options. Clin Cancer Res; 24(5); 1019–29. ©2017 AACR.

See related commentary by Fuchs, p. 991

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Highlights of This Issue

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Efficacy, Safety, and Pharmacokinetics of Axitinib in Nasopharyngeal Carcinoma: A Preclinical and Phase II Correlative Study

Purpose: We hypothesized that axitinib is active with an improved safety profile in nasopharyngeal carcinoma (NPC).

Experimental Design: We evaluated axitinib in preclinical models of NPC and studied its efficacy in a phase II clinical trial in recurrent or metastatic NPC patients who progressed after at least one line of prior platinum-based chemotherapy. We excluded patients with local recurrence or vascular invasion. Axitinib was started at 5 mg twice daily in continuous 4-week cycles. Primary endpoint was clinical benefit rate (CBR), defined as the percentage of patients achieving complete response, partial response, or stable disease by RECIST criteria for more than 3 months.

Results: We recruited 40 patients, who received a median of 3 lines of prior chemotherapy. Axitinib was administered for a mean of 5.6 cycles, with 16 patients (40%) receiving ≥6 cycles. Of 37 patients evaluable for response, CBR was 78.4% (95% CI, 65.6%–91.2%) at 3 months and 43.2% (30.4%–56.1%) at 6 months. Grade 3/4 toxicities were uncommon, including hypertension (8%), diarrhea (5%), weight loss (5%), and pain (5%). All hemorrhagic events were grade 1 (15%) or grade 2 (3%). Elevated diastolic blood pressure during the first 3 months of axitinib treatment was significantly associated with improved overall survival (HR, 0.29; 95% CI, 0.13–0.64, P = 0.0012). Patient-reported fatigue symptom was associated with hypothyroidism (P = 0.039). Axitinib PK parameters (C_max and AUC_(0-t)) were significantly correlated with tumor response, toxicity, and serum thyroid-stimulating hormone changes.

Conclusions: Axitinib achieved durable disease control with a favorable safety profile in heavily pretreated NPC patients. Clin Cancer Res; 24(5); 1030–7. ©2018 AACR.

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Synergistic Targeting of the Regulatory and Catalytic Subunits of PI3K{delta} in Mature B-cell Malignancies

Purpose: Aberrant activation of the B-cell receptor (BCR) is implicated in the pathogenesis of mature B-cell tumors, a concept validated in part by the clinical success of inhibitors of the BCR-related kinases BTK (Bruton's tyrosine kinase) and PI3K. These inhibitors have limitations, including the paucity of complete responses, acquired resistance, and toxicity. Here, we examined the mechanism by which the cyclic-AMP/PDE4 signaling axis suppresses PI3K, toward identifying a novel mechanism-based combinatorial strategy to attack BCR-dependency in mature B-cell malignancies.

Experimental Design: We used in vitro and in vivo diffuse large B-cell lymphoma (DLBCL) cell lines and primary chronic lymphocytic leukemia (CLL) samples to preclinically evaluate the effects of the combination of the FDA-approved phosphodiesterase 4 (PDE4) inhibitor roflumilast and idelalisib on cell survival and tumor growth. Genetic models of gain- and loss-of-function were used to map multiple signaling intermediaries downstream of the BCR.

Results: Roflumilast elevates the intracellular levels of cyclic-AMP and synergizes with idelalisib in suppressing tumor growth and PI3K activity. Mechanistically, we show that roflumilast suppresses PI3K by inhibiting BCR-mediated activation of the P85 regulatory subunit, distinguishing itself from idelalisib, an ATP-competitive inhibitor of the catalytic P110 subunit. Using genetic models, we linked the PDE4-regulated modulation of P85 activation to the oncogenic kinase SYK.

Conclusions: These data demonstrate that roflumilast and idelalisib suppress PI3K by distinct mechanisms, explaining the basis for their synergism, and suggest that the repurposing of PDE4 inhibitors to treat BCR-dependent malignancies is warranted. Clin Cancer Res; 24(5); 1103–13. ©2017 AACR.

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The Impact of Smoking and TP53 Mutations in Lung Adenocarcinoma Patients with Targetable Mutations--The Lung Cancer Mutation Consortium (LCMC2)

Purpose: Multiplex genomic profiling is standard of care for patients with advanced lung adenocarcinomas. The Lung Cancer Mutation Consortium (LCMC) is a multi-institutional effort to identify and treat oncogenic driver events in patients with lung adenocarcinomas.

Experimental Design: Sixteen U.S. institutions enrolled 1,367 patients with lung cancer in LCMC2; 904 were deemed eligible and had at least one of 14 cancer-related genes profiled using validated methods including genotyping, massively parallel sequencing, and IHC.

Results: The use of targeted therapies in patients with EGFR, ERBB2, or BRAF p.V600E mutations, ALK, ROS1, or RET rearrangements, or MET amplification was associated with a survival increment of 1.5 years compared with those with such mutations not receiving targeted therapy, and 1.0 year compared with those lacking a targetable driver. Importantly, 60 patients with a history of smoking derived similar survival benefit from targeted therapy for alterations in EGFR/ALK/ROS1, when compared with 75 never smokers with the same alterations. In addition, coexisting TP53 mutations were associated with shorter survival among patients with EGFR, ALK, or ROS1 alterations.

Conclusion: Patients with adenocarcinoma of the lung and an oncogenic driver mutation treated with effective targeted therapy have a longer survival, regardless of prior smoking history. Molecular testing should be performed on all individuals with lung adenocarcinomas irrespective of clinical characteristics. Routine use of massively parallel sequencing enables detection of both targetable driver alterations and tumor suppressor gene and other alterations that have potential significance for therapy selection and as predictive markers for the efficacy of treatment. Clin Cancer Res; 24(5); 1038–47. ©2017 AACR.

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Novel Targeting of Transcription and Metabolism in Glioblastoma

Purpose: Glioblastoma (GBM) is highly resistant to treatment, largely due to disease heterogeneity and resistance mechanisms. We sought to investigate a promising drug that can inhibit multiple aspects of cancer cell survival mechanisms and become an effective therapeutic for GBM patients.

Experimental Design: To investigate TG02, an agent with known penetration of the blood–brain barrier, we examined the effects as single agent and in combination with temozolomide, a commonly used chemotherapy in GBM. We used human GBM cells and a syngeneic mouse orthotopic GBM model, evaluating survival and the pharmacodynamics of TG02. Mechanistic studies included TG02-induced transcriptional regulation, apoptosis, and RNA sequencing in treated GBM cells as well as the investigation of mitochondrial and glycolytic function assays.

Results: We demonstrated that TG02 inhibited cell proliferation, induced cell death, and synergized with temozolomide in GBM cells with different genetic background but not in astrocytes. TG02-induced cytotoxicity was blocked by the overexpression of phosphorylated CDK9, suggesting a CDK9-dependent cell killing. TG02 suppressed transcriptional progression of antiapoptotic proteins and induced apoptosis in GBM cells. We further demonstrated that TG02 caused mitochondrial dysfunction and glycolytic suppression and ultimately ATP depletion in GBM. A prolonged survival was observed in GBM mice receiving combined treatment of TG02 and temozolomide. The TG02-induced decrease of CDK9 phosphorylation was confirmed in the brain tumor tissue.

Conclusions: TG02 inhibits multiple survival mechanisms and synergistically decreases energy production with temozolomide, representing a promising therapeutic strategy in GBM, currently under investigation in an ongoing clinical trial. Clin Cancer Res; 24(5); 1124–37. ©2017 AACR.

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CXCR4 Is a Potential Target for Diagnostic PET/CT Imaging in Barrett's Dysplasia and Esophageal Adenocarcinoma

Purpose: Barrett's esophagus represents an early stage in carcinogenesis leading to esophageal adenocarcinoma. Considerable evidence supports a major role for chronic inflammation and diverse chemokine pathways in the development of Barrett's esophagus and esophageal adenocarcinoma.

Experimental Design: Here we utilized an IL1β transgenic mouse model of Barrett's esophagus and esophageal adenocarcinoma and human patient imaging to analyze the importance of CXCR4-expressing cells during esophageal carcinogenesis.

Results: IL1β overexpression induces chronic esophageal inflammation and recapitulates the progression to Barrett's esophagus and esophageal adenocarcinoma. CXCR4 expression is increased in both epithelial and immune cells during disease progression in pL2-IL1β mice and also elevated in esophageal adenocarcinoma patient biopsy samples. Specific recruitment of CXCR4-positive (CXCR4⁺) immune cells correlated with dysplasia progression, suggesting that this immune population may be a key contributor to esophageal carcinogenesis. Similarly, with progression to dysplasia, there were increased numbers of CXCR4⁺ columnar epithelial cells at the squamocolumnar junction (SCJ). These findings were supported by stronger CXCR4-related signal intensity in ex vivo fluorescence imaging and autoradiography with advanced dysplasia. Pilot CXCR4-directed PET/CT imaging studies in patients with esophageal cancer demonstrate the potential utility of CXCR4 imaging for the diagnosis and staging of esophageal cancer.

Conclusion: In conclusion, the recruitment of CXCR4⁺ immune cells and expansion of CXCR4⁺ epithelial cells in esophageal dysplasia and cancer highlight the potential of CXCR4 as a biomarker and molecular target for diagnostic imaging of the tumor microenvironment in esophageal adenocarcinoma. Clin Cancer Res; 24(5); 1048–61. ©2017 AACR.

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Pharmacological Inhibition of NOS Activates ASK1/JNK Pathway Augmenting Docetaxel-Mediated Apoptosis in Triple-Negative Breast Cancer

Purpose: Chemoresistance in triple-negative breast cancer (TNBC) is associated with the activation of a survival mechanism orchestrated by the endoplasmic reticulum (EnR) stress response and by inducible nitric oxide synthase (iNOS). Our aim was to determine the effects of pharmacologic NOS inhibition on TNBC.

Experimental Design: TNBC cell lines, SUM-159PT, MDA-MB-436, and MDA-MB-468, were treated with docetaxel and NOS inhibitor (L-NMMA) for 24, 48, and 72 hours. Apoptosis was assessed by flow cytometry using Annexin-V and propidium iodide. Western blot was used to assess ER stress and apoptosis, and rtPCR was used to evaluate s-XBP1. TNBC patient-derived xenografts (PDX) were treated either with vehicle, docetaxel, or combination therapy (NOS inhibition + docetaxel). Mouse weight and tumor volumes were recorded twice weekly. Docetaxel concentration was determined using mass spectrometry. To quantify proliferation and apoptosis, PDX tumor samples were stained using Ki67 and TUNEL assay.

Results: In vitro, L-NMMA ameliorated the iNOS upregulation associated with docetaxel. Apoptosis increased when TNBC cells were treated with combination therapy. In TNBC PDXs, combination therapy significantly reduced tumor volume growth and increased survival proportions. In the BCM-5998 PDX model, intratumoral docetaxel concentration was higher in mice receiving combination therapy. Coupling docetaxel with NOS inhibition increased EnR-stress response via coactivation of ATF4 and CHOP, which triggered the pASK1/JNK proapoptotic pathway, promoting cleavage of caspases 3 and 9.

Conclusions: iNOS is a critical target for docetaxel resistance in TNBC. Pharmacologic inhibition of NOS enhanced chemotherapy response in TNBC PDX models. Combination therapy may improve prognosis and prevent relapse in TNBC patients who have failed conventional chemotherapy. Clin Cancer Res; 24(5); 1152–62. ©2018 AACR.

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Classifying Colorectal Cancer by Tumor Location Rather than Sidedness Highlights a Continuum in Mutation Profiles and Consensus Molecular Subtypes

Purpose: Colorectal cancers are classified as right/left-sided based on whether they occur before/after the splenic flexure, with established differences in molecular subtypes and outcomes. However, it is unclear if this division is optimal and whether precise tumor location provides further information.

Experimental Design: In 1,876 patients with colorectal cancer, we compared mutation prevalence and overall survival (OS) according to side and location. Consensus molecular subtype (CMS) was compared in a separate cohort of 608 patients.

Results: Mutation prevalence differed by side and location for TP53, KRAS, BRAFV600, PIK3CA, SMAD4, CTNNB1, GNAS, and PTEN. Within left- and right-sided tumors, there remained substantial variations in mutation rates. For example, within right-sided tumors, RAS mutations decreased from 70% for cecal, to 43% for hepatic flexure location (P = 0.0001), while BRAFV600 mutations increased from 10% to 22% between the same locations (P < 0.0001). Within left-sided tumors, the sigmoid and rectal region had more TP53 mutations (P = 0.027), less PIK3CA (P = 0.0009), BRAF (P = 0.0033), or CTNNB1 mutations (P < 0.0001), and less MSI (P < 0.0001) than other left-sided locations. Despite this, a left/right division preceding the transverse colon maximized prognostic differences by side and transverse colon tumors had K-modes mutation clustering that appeared more left than right sided. CMS profiles showed a decline in CMS1 and CMS3 and rise in CMS2 prevalence moving distally.

Conclusions: Current right/left classifications may not fully recapitulate regional variations in tumor biology. Specifically, the sigmoid-rectal region appears unique and the transverse colon is distinct from other right-sided locations. Clin Cancer Res; 24(5); 1062–72. ©2017 AACR.

See related commentary by Dienstmann, p. 989

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An integrative view of cell cycle control in Escherichia coli

Abstract

Bacterial proliferation depends on the cells' capability to proceed through consecutive rounds of the cell cycle. The cell cycle consists of a series of events during which cells grow, copy their genome, partition the duplicated DNA into different cell halves and, ultimately, divide to produce two newly formed daughter cells. Cell cycle control is of the utmost importance to maintain the correct order of events and safeguard the integrity of the cell and its genomic information. This review covers insights into the regulation of individual key cell cycle events in Escherichia coli. The control of initiation of DNA replication, chromosome segregation and cell division is discussed. Furthermore, we highlight connections between these processes. Although detailed mechanistic insight into these connections is largely still emerging, it is clear that the different processes of the bacterial cell cycle are coordinated to one another. This careful coordination of events ensures that every daughter cell ends up with one complete and intact copy of the genome, which is vital for bacterial survival.

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The human cytomegalovirus terminase complex as an antiviral target: a close-up view

Abstract

Human cytomegalovirus (HCMV) is responsible for life-threatening infections in immunocompromised individuals and can cause serious congenital malformations. Available antivirals target the viral polymerase but are subject to cross-resistance and toxicity. New antivirals targeting other replication steps and inducing fewer adverse effects are therefore needed. During HCMV replication, DNA maturation and packaging are performed by the terminase complex, which cleaves DNA to package the genome into the capsid. Identified in herpesviruses and bacteriophages, and with no counterpart in mammalian cells, these terminase proteins are ideal targets for highly specific antivirals. A new terminase inhibitor, letermovir, recently proved effective against HCMV in phase III clinical trials, but the mechanism of action is unclear. Letermovir has no significant activity against other herpesvirus or non-human CMV. This review focuses on the highly conserved mechanism of HCMV DNA-packaging and the potential of the terminase complex to serve as an antiviral target. We describe the intrinsic mechanism of DNA-packaging, highlighting the structure-function relationship of HCMV terminase complex components.

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Biochemistry of complex glycan depolymerisation by the human gut microbiota

Abstract

The human gut microbiota (HGM) makes an important contribution to health and disease. It is a complex microbial community of trillions of microbes with a majority of its members represented within two phyla, the Bacteroidetes and Firmicutes, although it also contains species of Actinobacteria and Proteobacteria. Reflecting its importance, the HGM is sometimes referred to as an 'organ' as it performs functions analogous to systemic tissues within the human host. The major nutrients available to the HGM are host and dietary complex carbohydrates. To utilise these nutrient sources, the HGM has developed elaborate, variable and sophisticated systems for the sensing, capture and utilisation of these glycans. Understanding nutrient acquisition by the HGM can thus provide mechanistic insights into the dynamics of this ecosystem, and how it impacts human health. Dietary nutrient sources include a wide variety of simple and complex plant and animal-derived glycans most of which are not degraded by enzymes in the digestive tract of the host. Here we review how various adaptive mechanisms that operate across the major phyla of the HGM contribute to glycan utilisation, focusing on the most complex carbohydrates presented to this ecosystem.

http://ift.tt/2EYn4wm

Please do not recycle! Translation reinitiation in microbes and higher eukaryotes

Abstract

Protein production must be strictly controlled at its beginning and end to synthesize a polypeptide that faithfully copies genetic information carried in the encoding mRNA. In contrast to viruses and prokaryotes, the majority of mRNAs in eukaryotes contain only one coding sequence, resulting in production of a single protein. There are, however, many exceptional mRNAs that either carry short open reading frames upstream of the main coding sequence (uORFs) or even contain multiple long ORFs. A wide variety of mechanisms have evolved in microbes and higher eukaryotes to prevent recycling of some or all translational components upon termination of the first translated ORF in such mRNAs and thereby enable subsequent translation of the next uORF or downstream coding sequence. These specialized reinitiation mechanisms are often regulated to couple translation of the downstream ORF to various stimuli. Here we review all known instances of both short uORF-mediated and long ORF-mediated reinitiation and present our current understanding of the underlying molecular mechanisms of these intriguing modes of translational control.

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Editorial: Editorial for the virtual issue on microbiome

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Group A streptococcal M-like proteins: From pathogenesis to vaccine potential

Abstract

M and M-like surface proteins from group A Streptococcus (GAS) act as virulence factors and have been used in multiple vaccine candidates. While the M protein has been extensively studied, the two genetically and functionally related M-like proteins, Mrp and Enn, although present in most streptococcal strains have been relatively less characterised. We compile the current state of knowledge for these two proteins, from discovery to recent studies on function and immunogenicity, using the M protein for comparison as a prototype of this family of proteins. We focus on the known interactions between M-like proteins and host ligand proteins, and analyse the genetic data supporting these interactions. We discuss known and possible functions of M-like proteins during GAS infections, and highlight knowledge gaps where further investigation is warranted.

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A physiological perspective on the origin and evolution of photosynthesis

Abstract

The origin and early evolution of photosynthesis are reviewed from an ecophysiological perspective. Earth's first ecosystems were chemotrophic, fueled by geological H₂ at hydrothermal vents and, required flavin-based electron bifurcation to reduce ferredoxin for CO₂ fixation. Chlorophyll-based phototrophy (chlorophototrophy) allowed autotrophs to generate reduced ferredoxin without electron bifurcation, providing them access to reductants other than H₂. Because high-intensity, short-wavelength electromagnetic radiation at Earth's surface would have been damaging for the first chlorophyll (Chl)-containing cells, photosynthesis probably arose at hydrothermal vents under low-intensity, long-wavelength geothermal light. The first photochemically active pigments were possibly Zn-tetrapyrroles. We suggest that (i) after the evolution of red-absorbing Chl-like pigments, the first light-driven electron transport chains reduced ferredoxin via a type-1 reaction center (RC) progenitor with electrons from H₂S; (ii) photothioautotrophy, first with one RC and then with two, was the bridge between H₂-dependent chemolithoautotrophy and water-splitting photosynthesis; (iii) photothiotrophy sustained primary production in the photic zone of Archean oceans; (iv) photosynthesis arose in an anoxygenic cyanobacterial progenitor; (v) Chl a is the ancestral Chl; and (vi), anoxygenic chlorophototrophic lineages characterized so far acquired, by horizontal gene transfer, RCs and Chl biosynthesis with or without autotrophy, from the architects of chlorophototrophy—the cyanobacterial lineage.

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The Burden of Illness of Idiopathic Pulmonary Fibrosis: A Comprehensive Evidence Review

Abstract

Background

Idiopathic pulmonary fibrosis (IPF) is a debilitating condition with significant morbidity and poor survival. Since 2010, there has been increased activity in the development of treatments that aim to delay progression of the disease.

Objective

Our study involves a comprehensive review of the literature for evidence on health-related quality of life (HRQoL), healthcare resource use (HCRU) and costs, and an assessment of the burden of illness of the condition.

Methods

We carried out a systematic literature review (SLR) to identify economic evaluations and HRQoL studies. We searched EMBASE, MEDLINE and MEDLINE In Process for relevant studies from database origins to April 2017. Alongside the presentation of the study characteristics and the available evidence, we carried out a qualitative comparison using reference population estimates for HRQoL and national health expenditure for costs.

Results

Our search identified a total of 3241 records. After removing duplicates and not relevant articles, we analysed 124 publications referring to 88 studies published between 2000 and 2017. Sixty studies were HRQoL and 28 were studies on costs or HCRU. We observed an exponential growth of publications in the last 3–5 years, with the majority of the studies conducted in Europe and North America. Among the HRQoL studies, and despite regional differences, there was some agreement between estimates on the absolute and relative level of HRQoL for patients with IPF compared with the general population. Regarding costs, after adjustments for the cost years and currency, the suggested annual per capita cost of patients with IPF in North America was estimated around US$20,000, 2.5–3.5 times higher than the national healthcare expenditure. Additionally, studies that analysed patients with IPF alongside a matched control cohort suggested a significant increase in resource use and cost.

Conclusion

The reviewed evidence indicates that IPF has considerable impact on HRQoL, relative to the general population levels. Furthermore, in studies of cost and resource use, most estimates of the burden were consistent in suggesting an excess cost for patients with IPF compared with a control cohort or the national health expenditure. This confirms IPF as a growing threat for public health worldwide, with considerable impact to the patients and healthcare providers.

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Biokinetic and dosimetric aspects of 64 CuCl 2 in human prostate cancer: possible theranostic implications

Abstract

Background

The aim of the present study is to evaluate the kinetics and dosimetry of ⁶⁴CuCl₂ in human prostate cancer (PCa) lesions.

We prospectively evaluated 50 PCa patients with biochemical relapse after surgery or external beam radiation therapy. All patients underwent ⁶⁴CuCl₂-PET/CT to detect PCa recurrence/metastases. Volumes of interest were manually drawn for each ⁶⁴CuCl₂ avid PCa lesion with a diameter > 1 cm on mpMRI in each patient. Time-activity curves for all lesions were obtained. The effective and biological half-life and the standard uptake values (SUVs) were calculated. Tumour/background ratio (TBR) curves as a function of time were considered. Finally, the absorbed dose per lesion was estimated.

Results

The mean effective half-life of ⁶⁴CuCl₂ calculated in the lymph nodes (10.2 ± 1.7 h) was significantly higher than in local relapses (8.8 ± 1.1 h) and similar to that seen in bone metastases (9.0 ± 0.4 h). The mean ⁶⁴CuCl₂ SUV_max calculated 1 h after tracer injection was significantly higher in the lymph nodes (6.8 ± 4.3) and bone metastases (6.8 ± 2.9) than in local relapses (4.7 ± 2.4). TBR mean curve of ⁶⁴CuCl₂ revealed that the calculated TBR_max value was 5.0, 7.0, and 6.2 in local relapse and lymph node and bone metastases, respectively, and it was achieved about 1 h after ⁶⁴CuCl₂ injection. The mean absorbed dose of the PCa lesions per administrated activity was 6.00E-2 ± 4.74E-2mGy/MBq. Indeed, for an administered activity of 3.7 GBq, the mean dose absorbed by the lesion would be 0.22 Gy.

Conclusions

Dosimetry showed that the dose absorbed by PCa recurrences/metastases per administrated activity was low. The dosimetric study performed does not take into account the possible therapeutic effect of the Auger electrons. Clinical trials are needed to evaluate ⁶⁴Cu internalization in the cell nucleus that seems related to the therapeutic effectiveness reported in preclinical studies.

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Assessment of health-related quality of life in spine treatment: conversion from SF-36 to VR-12

Publication date: Available online 28 February 2018
Source:The Spine Journal
Author(s): Matthew F. Gornet, Anne G. Copay, Katrine M. Sorensen, Francine W. Schranck
Background Context.Health-related quality-of-life outcomes have been collected with the Medical Outcomes Study (MOS) Short Form 36 (SF-36) survey. Boston University School of Public Health has developed algorithms for the conversion of SF-36 to VR-12 physical component summary (PCS) and mental component summary (MCS).Purpose.The purpose of this study is to investigate the conversion of the SF-36 to VR-12 PCS and MCS scores.Study Design.Preoperative and postoperative SF-36 were collected from patients who underwent lumbar and/or cervical surgery from a single surgeon between August 1998 and January 2013.Methods.SF-36 PCS and MCS scores were calculated following their original instructions. The SF-36 answers were then converted to VR-12 PCS and MCS scores following the algorithm provided by the Boston University School of Public Health. The mean score, preoperative to postoperative change, and proportions of patients who reach the minimum detectable change were compared between SF-36 and VR-12.Results.A total of 1968 patients (1559 lumbar and 409 cervical) had completed preoperative and postoperative SF-36. The values of the SF-36 and VR-12 mean scores were extremely similar with score differences ranging from 0.77 to 1.82. The preoperative to postoperative improvement was highly significant (p<0.001) for both SF-36 and VR-12 scores. The mean change score were similar with a difference of up to 0.93 for PCS and up to 0.37 for MCS. Minimum Detectable Change (MDC) values were almost identical for SF-36 and VR-12 with a 0.12 difference for PCS and up to 0.41 for MCS. The proportions of patients whose change in score reached MDC were also nearly identical for SF-36 and VR-12. About 90% of the patients above SF-36 MDC were also above VR-12 MDC.Conclusions.The converted VR-12 scores, similarly to the SF-36 scores, detect a significant postoperative improvement in PCS and MCS score. The calculated MDC values and the proportions of patients whose score improvement reach MDC are similar for both SF-36 and VR-12.



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Rod fracture in adult spinal deformity surgery fused to the sacrum: prevalence, risk factors and impact on health related quality of life in 526 patients

Publication date: Available online 28 February 2018
Source:The Spine Journal
Author(s): Thamrong Lertudomphonwanit, Michael P. Kelly, Keith H. Bridwell, Lawrence G. Lenke, Steven J. McAnany, Prachya Punyarat, Timothy P. Bryan, Jacob M. Buchowski, Lukas P. Zebala, Brenda A. Sides, Karen Steger-May, Munish C. Gupta
Background contextRisk factors associated with rod fracture (RF) following adult spinal deformity (ASD) surgery fused to the sacrum remain debatable and the impact of RF on patient-reported outcomes (PROs) after ASD surgery has not been investigated.PurposeTo evaluate the prevalence of and risk factors for RF and determine PROs change associated with RF after ASD surgery fused to the sacrum.Study Design/SettingRetrospective single-center cohort.Patient SamplePatients undergoing long-construct posterior spinal fusions to the sacrum performed at a single institution by two senior spine surgeons from 2004 to 2014 were included.Outcome MeasuresPatient demographics, radiographic parameters and surgical factors were assessed for risk factors associated with RF. Oswestry Disability Index (ODI) and Scoliosis Research Society-30 (SRS-30) scores were assessed at baseline, 1-year postoperatively and latest follow-up.MethodsInclusion criteria were ASD patients age >18 who had ≥5 vertebrae instrumented and fused posteriorly to the sacrum and either development of RF or no development of RF with minimum 2-year follow-up. Patient characteristics, operative data, radiographic parameters and PROs were analyzed at baseline and follow-up. Separate Cox proportional hazard models based on rod material and diameter were used to determine factors associated with RF.ResultsFive hundred twenty-six patients (80%) were available for analysis. RF occurred in 97 (18.4%) patients (unilateral RF n=61 [63%]; bilateral RF n=36 [37%]). Risk factors for fracture of 5.5mm cobalt chromium (CC) instrumentation (CC 5.5 model) included preoperative sagittal vertical axis (hazard ratio [HR] 1.07 [95% confidence interval (95%CI) 1.02 to 1.14] per 1-cm increase), preoperative thoracolumbar kyphosis (HR 1.02 [95%CI 1.01 to 1.04] per 1-degree increase) and number of levels fused for patients that received rhBMP-2 <12 mg per level fused (HR, 1.48 [95%CI 1.20 to 1.82] per 1-level increase). 5.5mm CC implants were at a higher risk for fracture than 6.35mm stainless steel (SS) constructs (HR, 8.49 [95%CI 4.26 to 16.89]). The RF group had less overall improvement in SRS Satisfaction (0.93 vs 1.32; p=0.007) and SRS Self-image domain scores (0.72 vs 1.02; p=0.01). The bilateral RF group had less overall improvement in ODI (8.1 vs 15.8; p=0.02), SRS Subscore (0.51 vs 0.85; p=0.03) and SRS Pain domain scores (0.48 vs 0.95; p=0.02) compared to the non-RF group at final follow-up.ConclusionsThe prevalence of all RF after index procedures was 18.4%, 37% for bilateral RF. Greater preoperative sagittal vertical axis, greater preoperative thoracolumbar kyphosis, increased number of vertebrae fused for patients that received rhBMP-2 <12 mg per level fused, and CC 5.5 mm rod were associated with RF. Less improvement in patient satisfaction and self-image was noted in the RF group. Furthermore, bilateral RF significantly affected PROs as measured by ODI and SRS Subscore at final follow-up.



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A novel preoperative trajectory evaluation method for l5-s1 transforaminal percutaneous endoscopic lumbar discectomy

Publication date: Available online 28 February 2018
Source:The Spine Journal
Author(s): Sang Soo Eun, Sang-Ho Lee, Wei Chiang Liu, H. Yener Erken
Background contextL5-S1 transforaminal PELD is a demanding procedure due to structures like iliac crest, L5 transverse process, hypertrophic L5-S1 facet joint, and sacral ala. There has been no definite preoperative evaluation method to evaluate the surgical validity of L5-S1 transforaminal PELD.PurposeAuthors report a new preoperative trajectory evaluation method for L5-S1 transforaminal PELD using magnetic resonance imaging (MRI) or computed tomography (CT) examinationsStudy design/settingTechnical ReportsPatient samplePatients who were diagnosed as L5-S1 soft disc herniationOutcome measuresSuccess rate of transforaminal PELD according to height of iliac crestMethodsTwelve patients who were diagnosed L5-S1 disc herniation were preoperatively evaluated with this new method. Skin marker is attached to patient's back as a tentative skin entry point which was determined by usual preoperative MRI or CT. A new tilted axial and coronal MRI or CT scan is performed according to axis of L5S1 transforaminal working channel. These images will show good relationship between working channel and iliac crest.ResultsSix patients were decided to undergo a transforaminal PELD and results were successful. The other six patients were considered to be "unsuitable" for transforaminal PELD because of the probable blockade by iliac crest.ConclusionThe tilted MRI or CT can provide precise evaluation for L5S1 transforaminal PELD trajectory and may achieve good outcome.



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Editorial Board

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Autonomic rhythms in health and disease

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Corrigendum

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A Nonsense Variant in the ACADVL Gene in German Hunting Terrier Dogs with Exercise Induced Metabolic Myopathy

Several enzymes are involved in fatty acid oxidation, which is a key process in mitochondrial energy production. Inherited defects affecting any step of fatty acid oxidation can result in clinical disease. We present here an extended family of German Hunting Terriers with 10 dogs affected by clinical signs of exercise induced weakness, muscle pain, and suspected rhabdomyolysis. The combination of clinical signs, muscle histopathology and acylcarnitine analysis with an elevated tetradecenoylcarnitine (C14:1) peak suggested a possible diagnosis of acyl-CoA dehydrogenase very long chain deficiency (ACADVLD). Whole genome sequence analysis of one affected dog and 191 controls revealed a nonsense variant in the ACADVL gene encoding acyl-CoA dehydrogenase very long chain, c.1728C>A or p.(Tyr576*). The variant showed perfect association with the phenotype in the 10 affected and more than 500 control dogs of various breeds. Pathogenic variants in the ACADVL gene have been reported in humans with similar myopathic phenotypes. We therefore considered the detected variant to be the most likely candidate causative variant for the observed exercise induced myopathy. To our knowledge, this is the first description of this disease in dogs, which we propose to name exercise induced metabolic myopathy (EIMM), and the identification of the first canine pathogenic ACADVL variant. Our findings provide a large animal model for a known human disease and will enable genetic testing to avoid the unintentional breeding of affected offspring.

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