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The diversity of the V3 loop tip motif sequences of HIV-1 subtype B was analyzed in patients from Botucatu (Brazil) and Montpellier (France). Overall, 37 tetrameric tip motifs were identified, 28 and 17 of them being recognized in Brazilian and French patients, respectively. The GPGR (P) motif was predominant in French but not in Brazilian patients (53.5% vs 31.0%), whereas the GWGR (W) motif was frequent in Brazilian patients (23.0%) and absent in French patients. Three tip motif groups were considered: P, W, and non-P non-W groups. The distribution of HIV-1 isolates into the three groups was significantly different between isolates from Botucatu and from Montpellier (P < 0.001). A higher proportion of CXCR4-using HIV-1 (X4 variants) was observed in the non-P non-W group as compared with the P group (37.5% vs 19.1%), and no X4 variant was identified in the W group (P < 0.001). The higher proportion of X4 variants in the non-P non-W group was essentially observed among the patients from Montpellier, who have been infected with HIV-1 for a longer period of time than those from Botucatu. Among patients from Montpellier, CD4+ cell counts were lower in patients belonging to the non-P non-W group than in those belonging to the P group (24 cells/μL vs 197 cells/μL; P = 0.005). Taken together, the results suggest that variability of the V3 loop tip motif may be related to HIV-1 coreceptor usage and to disease progression. However, as analyzed by a bioinformatic method, the substitution of the V3 loop tip motif of the subtype B consensus sequence with the different tip motifs identified in the present study was not sufficient to induce a change in HIV-1 coreceptor usage.

Inactivation of mismatch repair (MMR) is the cause of the common cancer predisposition disorder Lynch syndrome (LS), also known as hereditary nonpolyposis colorectal cancer (HNPCC), as well as 10-40% of sporadic colorectal, endometrial, ovarian, gastric, and urothelial cancers. Elevated mutation rates (mutator phenotype), including simple repeat instability [microsatellite instability (MSI)] are a signature of MMR defects. MicroRNAs (miRs) have been implicated in the control of critical cellular pathways involved in development and cancer. Here we show that overexpression of miR-155 significantly down-regulates the core MMR proteins, hMSH2, hMSH6, and hMLH1, inducing a mutator phenotype and MSI. An inverse correlation between the expression of miR-155 and the expression of MLH1 or MSH2 proteins was found in human colorectal cancer. Finally, a number of MSI tumors with unknown cause of MMR inactivation displayed miR-155 overexpression. These data provide support for miR-155 modulation of MMR as a mechanism of cancer pathogenesis.

Unlabelled: Although the inflammation-associated cytokine interleukin-6 (IL-6) has been implicated in cholangiocarcinoma growth, the relationship between IL-6 and oncogenic changes is unknown. IL-6 can increase expression of DNA methyltransferase-1 (DNMT-1) and epigenetically regulate the expression of several genes, including microRNAs (miRNAs). DNMT-1 up-regulation occurs in hepatobiliary cancers and is associated with a poor prognosis. To understand the potential regulation of DNMT-1 by IL-6-dependent miRNAs, we examined the expression of a group of miRNAs which have sequence complementarity to the 3'-untranslated region of DNMT-1, namely miR-148a, miR-152, and miR-301. The expression of these miRNAs was decreased in cholangiocarcinoma cells. Moreover, the expression of all three miRNAs was decreased in IL-6-overexpressing malignant cholangiocytes in vitro and in tumor cell xenografts. There was a concomitant decrease in expression of the methylation-sensitive tumor suppressor genes Rassf1a and p16INK4a. Using luciferase reporter constructs, DNMT-1 was verified as a target for miR-148a and miR-152. Precursors to miR-148a and miR-152 decreased DNMT-1 protein expression, increased Rassf1a and p16INK4a expression, and reduced cell proliferation., Conclusion: These data indicate that IL-6 can regulate the activity of DNMT-1 and expression of methylation-dependent tumor suppressor genes by modulation of miR-148a and miR-152, and provide a link between this inflammation-associated cytokine and oncogenesis in cholangiocarcinoma.

Purpose: Hepatocellular cancer (HCC) is highly resistant to chemotherapy and is associated with poor prognosis. Chronic hepatitis C virus (HCV) infection is a major cause of HCC. However, the effect of viral proteins in mediating chemosensitivity in tumor cells is unknown. We postulated that HCV viral proteins could modulate therapeutic responses by altering host cell microRNA (miRNA) expression., Experimental Design: HepG2 malignant hepatocytes were stably transfected with full-length HCV genome (Hep-394) or an empty vector (Hep-SWX). MiRNA profiling was done by using a custom microarray, and the expression of selected miRNAs was validated by real-time PCR. Protein expression was assessed by Western blotting, whereas caspase activation was assessed by a luminometric assay., Results: The IC(50) to sorafenib was lower in Hep-394 compared with Hep-SWX control cells. Alterations in miRNA expression occurred with 10 miRNAs downregulated >2-fold and 23 miRNAs upregulated >2-fold in Hep-394 cells compared with controls. Of these, miR-193b was overexpressed by 5-fold in Hep-394 cells. miR-193b was predicted to target Mcl-1, an antiapoptotic protein that can modulate the response to sorafenib. The expression of Mcl-1 was decreased, and basal caspase-3/7 activity and poly ADP ribose polymerase cleavage were increased in Hep-394 cells compared with controls. Moreover, transfection with precursors to miR-193b decreased both Mcl-1 expression and the IC(50) to sorafenib., Conclusions: Cellular expression of full-length HCV increases sensitivity to sorafenib by the miRNA-dependent modulation of Mcl-1 and apoptosis. Modulation of miRNA responses may be a useful strategy to enhance response to chemotherapy in HCC.

Background: The presence of vascular invasion in hepatocellular cancer (HCC) correlates with prognosis, and is a critical determinant of both the therapeutic approach and the recurrence or intrahepatic metastases. The authors sought to identify candidate therapeutic agents capable of targeting the invasive phenotype in HCC., Methods: A gene expression signature associated with vascular invasion derived from 81 human cases of HCC was used to screen a database of 453 genomic profiles associated with 164 bioactive molecules using the connectivity map. Candidate agents were identified by their inverse correlation to the query gene signature. The efficacy of the candidate agents to target invasion was experimentally verified in PLC/PRF-5 and HepG2 HCC cells., Results: The gene signature associated with vascular invasion in HCC comprised of 47 up-regulated and 26 down-regulated genes. Computational bioinformatics analysis revealed several putative candidates, including resveratrol and 17-allylamino-geldanamycin (17-AAG). Both of these agents reduced HCC cell invasion at noncytotoxic concentrations. 17-AAG, a heat shock protein 90 (HSP-90) inhibitor, was shown to modulate the expression of several diverse cancer-associated genes, including ADAMTS1, part of the query signature, and maspin, an HSP-90-associated protein with a tumor suppressor role in HCC., Conclusions: Candidates for further evaluation as therapies to limit invasion in HCC have been identified using a computational bioinformatics analysis of phenotype-associated gene expression. Phenotype targeting using genomic profiling is a rational approach for drug discovery. Therapeutic strategies targeting a defined cancer-associated phenotype can be identified without a detailed knowledge of individual downstream targets.

Background: Green tea polyphenols are chemopreventive in several cancer models but their use as adjunctive therapeutic agents for cancer is unknown., Aims: Cholangiocarcinomas respond poorly to chemotherapeutic agents and our aims were to assess the utility of green tea polyphenols as adjuncts to chemotherapy for cholangiocarcinoma., Materials and Methods: We assessed the effect of purified green tea catechins on chemotherapy-induced apoptosis in KMCH, CC-LP-1 and Mz-ChA-1 human cholangiocarcinoma cells, and on chemosensitivity of Mz-ChA-1 cell xenografts in nude mice., Results: Epigallocatechin-gallate (EGCG), but not the structurally related catechin epigallocatechin, sensitized cells to apoptosis induced by gemcitabine (GEM), mitomycin C or 5-fluorouracil in vitro. Mitochondrial membrane depolarization, cytosolic cytochrome c expression and apoptosis were increased in cells incubated with EGCG and GEM compared with either agent alone. Furthermore, EGCG decreased in vivo growth and increased the sensitivity to GEM of Mz-ChA-1 cell xenografts in nude mice., Conclusions: The green tea polyphenol EGCG sensitizes human cholangiocarcinoma cells to chemotherapy-induced apoptosis and warrants evaluation as an adjunct to chemotherapy for the treatment of human cholangiocarcinoma.

Aims and Background: We evaluated the activity in terms of time to progression (TTP) of mitomycin C and capecitabine in patients with advanced colorectal cancer who progressed after 2 lines of chemotherapy., Methods: Patients with advanced colorectal cancer undergoing third-line chemotherapy after failure of 5-FU with CPT-11 or oxaliplatin-based chemotherapy regimens were treated with capecitabine and mitomycin C., Results: Sixty-one patients were enrolled in this study. The median age was 55 years (range, 26-78 years) and the male:female ratio 21:40. We observed partial remissions in 5 patients (8%), stable disease in 25 patients (40%) and progression of disease in 31 patients (52%). Median TTP was 3 months and median survival was 6 months. Global toxicity was mild and entirely acceptable. Grade 3-4 hematological toxicity occurred in 12 patients and grade 3-4 nonhematological toxicity in 5 patients., Conclusions: The combination of capecitabine and mitomycin C could represent an effective and manageable treatment option for colorectal cancer patients failing previous chemotherapy regimens.

Objective: The aim of this study was to evaluate the feasibility of a combination of epirubicin and paclitaxel followed by intravenous (iv) cyclophosphamide, methotrexate, and 5-fluorouracile (CMF) as adjuvant treatment of breast cancer patients with 10 or more metastatic axillary lymph nodes., Methods: Forty-four patients entered this multicenter study and received 4 cycles of epirubicin (E 120 mg/m2 day 1, q3 weeks) and paclitaxel (T 135 mg/m2 day 1, q3 weeks), followed by 4 cycles of iv CMF (days 1 and 8, q4 weeks). Patients with positive hormonal receptors received sequentially tamoxifen associated with LH-RH analogue if premenopausal. The endpoints were the evaluation of the feasibility of this schedule and disease free survival (DFS)., Results: Median age of patients was 55; median number of positive axillary nodes was 14 (range, 10-47). Hormonal receptor status was positive in 57% of patients. The combination of epirubicin and paclitaxel was well tolerated; NCI grade 3/4 events were: leucopenia in 27% of patients, neutropenic fever in 5 patients, anemia in 7%, thrombocytopenia in 7%, nausea in 18%, vomiting in 14%, and neurotoxicity in 4%. CMF regimen caused a few cases of grade 3/4 hematologic toxicity. No cardiac toxicity was recorded. With a median follow-up of 59 months, 18 (41%) patients relapsed. Sites of relapse were mainly bone, skin/soft tissues, liver, and lung. Median DFS was 78 months, with a 5-year rate of 60%., Conclusions: The combination of paclitaxel at low dose and epirubicin followed by CMF is a feasible regimen, which seems to be effective in high-risk node positive breast cancer patients and requires further investigations.

Modern oncology often obtains good results against earlier neoplasms, whilst it's still in difficulties against the advanced ones. The knowledge of paraneoplastic syndromes is crucial both to cure patients and to do an earlier diagnosis. When we recognize a paraneoplastic syndrome that comes before the clinic beginning of a neoplasm, perhaps we save a life. This review discusses all the main paraneoplastic syndromes, focusing mainly on their clinical aspect and reminding the most commonly associated cancers.