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Hepatocellular carcinoma (HCC) accounts for the majority of primary liver cancers. Clearly identifiable risk factors are lacking in up to 30% of HCC patients and most of these cases are attributed to non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH). Beyond the known risk factors for NAFLD, the intestinal microbiota, in particular dysbiosis (defined as any change in the composition of the microbiota commonly found in healthy conditions) is emerging as a new factor promoting the development of chronic liver diseases and HCC. Intestinal microbes produce a large array of bioactive molecules from mainly dietary compounds, establishing an intense microbiota-host transgenomic metabolism with a major impact on physiological and pathological conditions. A better knowledge of these 'new' pathways could help unravel the pathogenesis of HCC in NAFLD to devise new prevention strategies. Currently unsettled issues include the relative role of a 'negative microbiota' (in addition to the other known risk factors for NASH) and the putative prevention of NAFLD through modulation of the gut microbiota. [ABSTRACT FROM AUTHOR]

Background. The use of gemcitabine as an adjuvant modality for cholangiocarcinoma (CC) is increasing, but limited data are available on predictive biomarkers of response. Human equilibrative nucleoside transporter 1 (hENT-1) is the major transporter involved in gemcitabine intracellular uptake. This study investigated the putative predictive role of hENT-1 localization in tumor cells of CC patients undergoing treatment with adjuvant gemcitabine. Methods. Seventy-one consecutive patients with resected CC receiving adjuvant gemcitabine at our center were retrospectively analyzed by immunohistochemistry for hENT-1 localization in tumor cells. The main outcome measure was disease-free survival (DFS). Hazard ratios (HRs) of relapse and associated 95% confidence intervals (CIs) were obtained from proportional hazards regression models stratified on quintiles of propensity score. Results. Twenty-three (32.4%) cases were negative for hENT-1, 22 (31.0%) were positive in the cytoplasm only, and 26 (36.6%) showed concomitant cytoplasm/membrane staining. Patients with membrane hENT-1 had a longer DFS (HR 0.49, 95% CI 0.24-0.99, p = .046) than those who were negative or positive only in the cytoplasm of tumor cells. Notably, the association between DFS and membrane hENT-1 was dependent on the number of gemcitabine cycles (one to two cycles: HR 0.96, 95% CI0.34-2.68; three to four cycles: HR 0.99,95% CI 0.34-2.90; five to six cycles: HR 0.27, 95% CI 0.10-0.77). Conclusion. hENT-1 localization on tumor cell membrane may predict response to adjuvant gemcitabine in CC patients receiving more than four cycles of chemotherapy. Further prospective randomized trials on larger populations are required to confirm these preliminary results, so that optimal gemcitabine-based chemotherapy may be tailored for CC patients in the adjuvant setting. [ABSTRACT FROM AUTHOR]

Approximately 10%–15% of gastrointestinal stromal tumors (GISTs) in adults do not harbor any mutation in the KIT or PDGFRA genes (ie, KIT/PDGFRA wild-type GISTs). Recently, mutations in SDHB and SDHC (which encode succinate dehydrogenase subunits B and C, respectively) but not in SDHA and SDHD (which encode subunits A and D, respectively) were identified in KIT/PDGFRA wild-type GISTs. To search for novel pathogenic mutations, we sequenced the tumor transcriptome of two young adult patients who developed sporadic KIT/PDGFRA wild-type GISTs by using a massively parallel sequencing approach. The only variants identified as disease related by computational analysis were in SDHA. One patient carried the homozygous nonsense mutation p.Ser384X, the other patient was a compound heterozygote harboring a p.Arg31X nonsense mutation and a p.Arg589Trp missense mutation. The heterozygous nonsense mutations in both patients were present in germline DNA isolated from peripheral blood. Protein structure analysis indicates that all three mutations lead to functional inactivation of the protein. This is the first report, to our knowle dge, that identifies SDHA inactivation as a common oncogenic event in GISTs that lack a mutation in KIT and PDGFRA. [ABSTRACT FROM PUBLISHER]

Studies suggest that cell proliferation abnormalities of the colorectal mucosa are associated with risk of neoplasia, and most cancers of the large bowel are thought to arise from adenomas, The results of other studies suggest that vitamins A, C, and E have chemopreventive efficacy against colon cancer in animal models. This study evaluates the effect of dietary vitamin supplementation on cell kinetics in uninvolved rectal mucosa in patients with colorectal adenomas. Twenty patients with colorectal adenomas were given vitamins A, C, and E for 6 months after complete polypectomy, and 21 patients with adenomas received placebo. In each patient, six biopsy specimens were taken from normal-appearing rectal mucosa before treatment and after 3 and 6 months of treatment and were incubated with tritiated thymidine ([H]thymidine), and the [H]thymidine-labeled cells were counted by use of autoradiography. Two parameters of cell proliferation were evaluated: 1) the ratio of the number of cells to the total number of cells (thymidine labeling index) and 2) the ratio of the number of labeled cells in the upper 40% of the crypt to the total number of labeled cells in the crypt (Φh). The latter index reflects abnormal expansion of the proliferative compartment and is thought to be an intermediate biomarker of cancer risk. In patients receiving vitamins, Φh decreased progressively from baseline values, with increasing statistical significance (<.05 after 3 months, <.01 after 6 months). There was a statistically significant decrease in the thymidine labeling index in the 40% of the crypt near the mucosal surface, but the variation in the overall labeling index was not statistically significant. In the placebo group, we observed no statistically significant change in cell kinetics. These findings suggest that vitamin A, C, and E supplementation is effective in reducing abnormalities in cell kinetics that may indicate a precancerous condition. Before larger trials on chemoprevention of colorectal adenoma recurrence are conducted, additional studies are needed (a) to validate that cell kinetics is an intermediate biomarker, (b) to determine active agents, optimal dosage, and the relative efficacy of agents given alone and in combination, and (c) to test toxicity. [J Natl Cancer Inst 84: 47–51, 1992] [ABSTRACT FROM PUBLISHER]

Brandi et al. clarify data about the localization of human equilibrative nucleoside transporter 1 in cancer patients receiving gemcitabine‐based chemotherapy. They discuss methodology, differences between antibodies, and recommendations for further study. [ABSTRACT FROM AUTHOR]

Background. Anti-angiogenic treatment with targeted agents is effective in advanced hepatocellular carcinoma (HCC). This trial evaluated the safety and efficacy of metronomic capecitabine in patients with HCC. Methods. This single-institution phase II trial included 59 previously untreated patients with advanced HCC and 31 patients resistant to or intolerant of sorafenib. The treatment schedule was capecitabine 500 mg twice daily until progression of disease, unacceptable toxicity level, or withdrawal of informed consent.Progression- free survival (PFS) was chosen as the primary endpoint. Results. A total of 59 previously untreated and 31 previously treated patients with HCC were enrolled. The first cohort achieved a median PFS of 6.03 months and an overall survival (OS) of 14.47 months. Two patients achieved a complete response, 1 patient achieved partial response, and in 30 patients, stable disease was the best outcome. The second cohort achieved a median PFS of 3.27 months and a median OS of 9.77 months.No complete or partial responses were observed, but 10 patients had stable disease. An unscheduled comparison of the first cohort of patients with 3,027 untreated patients with HCC from the Italian Liver Cancer(ITA.LI.CA) database was performed.One-to-one matching according to demographic/ etiologic/oncologic features was possible for 50 patients. The median OS for these 50 capecitabine-treated patients was15.6 months,compared with a median OS of 8.0 months for the matched untreated patients (p_.043). Conclusion. Metronomic capecitabine is well tolerated by patients with advanced HCC and appears to have activity both in treatment-naive patients and in those previously treated with sorafenib. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to a study titled "Effect of Simvastatin on Cetuximab Resistance in Human Colorectal Cancer with KRAS Mutations," by J. Lee, I. Lee , B. Han, et al. published online on March 11, 2011.