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Colorectal cancer (CRC) is one of the most frequent neoplasms worldwide, and up to 15% have a family history. Lynch syndrome (LS) is a hereditary cause of CRC and gastric (GC). Individuals with LS have mutations in mismatch genes repair. p53, cyclin D1, β-catenin, APC and c-myc proteins are involved in the cell cycle and carcinogenesis. Objective: To study the expression of p53, Cyclin D1, β-catenin, APC and c-myc proteins in patients with CRC and GC with at least one of the Bethesda positive criteria. Compare the expression of these proteins with the presence or absence of expression of the DNA repair proteins. Patients and Methods: We included 70 individuals with CRC or GC with at least one of the Bethesda positive criteria. Protein expression of MLH1, MSH2, MSH6, PMS2, p53, cyclin D1, β-catenin, APC and c-myc were analized by immunohistochemistry tumours tissues. Results: Deficient expression of MLH1, MSH2, MSH6 and PMS2 were respectively 38.7%; 17.7%; 26.22% and 48.38%. We found a negative association between deficiency of PMS2 and age, and positive association between PMS2 deficiency and APC positive. The positive imunoexpression of APC increases by 4 times the chance of having deficiency of PMS2. Conclusions: Patients with loss of expression of PMS2 had a higher risk of mutation or deletion of APC and tumours with positive immunoexpression of cyclin D1 had an increased risk of loss of expression of MSH2. These results suggest that tumours with loss of expression of DNA repair proteins had a higher loss of cell control cycle.

Background: Colorectal cancer (CRC) is one of the most frequent cancers. Genetic mutations in CRC already described can be detected in feces. Microarray methods in feces can represent a new diagnostic tool for CRC and significant improvement at public health. Aim: to analyze stool DNA by human DNA quantify and microarray methods as alternatives to CRC screening. Method: Three methods were analyzed in stool samples: Human DNA Quantify, RanplexCRC and KRAS/BRAF/PIK3CA (KBP) Arrays. Results: KBP array mutations were presented in 60.7% of CRC patients and RanplexCRC Array mutations in 61.1% of CRC patients. Sensitivity and specificity for human DNA quantification was 66% and 82% respectively. Fecal KBP Array had 35% sensitivity and 96% specificity and RanplexCRC Array method had 78% sensitivity and 100% specificity. Conclusion: Microarray methods showed promise as potential biomarkers for CRC screening; however, these methods had to be optimized to improve accuracy and applicability by clinical routine.

Background Despite the decreased incidence, gastric cancer is still a frequent cause of cancer related death. The 1st line 2 or 3 drugs regimen is still a debatable issue. HER2 targeted therapy has emerged as the standard of care, but it is unavailable in the Brazilian Public Health System. The end-point of this trial was overall survival (OS) in patients with metastatic gastric cancer treated in a public university hospital in Brazil. The secondary end-points were efficacy and safety of regimens with 2 (F+P) or 3 (EOX) drugs to develop an institutional guideline to facilitate optimal treatments. Materials and methods In this retrospective study, 1st line regimens were evaluated for OS and PFS stratified by age and ECOG using Cox regression. Results 47 patients were treated over the last 3 years. In 1st line, 29 were treated with F+P (mean 59.3 years, 34.5% ECOG 2 and a mean of 5.69 cycles) and 16 with EOX (mean 47 years, 18.8% ECOG 2 and a mean of 5.44 cycles). The median OS was 13.8 months (95%CI 10.7-16.9). Response was evaluated in 40 cases and was 64.3% for EOX and 37.5% for F+P (p=0.25). The median PFS was 9.5 months for EOX and 5.6 months for F+P (HR 0.85, 95%CI 0.41-1.74). However, among patients with ECOG 2 mPFS was 3.70 vs 5.40 months, respectively (p=0.86). Regimens showed similar manageable adverse events. A total of 34 patients suffered progression and 14 received 2nd line therapy. Diffuse histology (HR 1.89, 95%CI 1.22-2.88), achieving 2nd line (HR: 0.25, 95%CI 0.11-0.58) and treatment response (HR 0.23, 95%CI 0.12-0.47) were OS prognostic factors. Conclusions Patients treated in our hospital had outcomes compatible with the literature. The regimen choice should be related to patient features. Second line treatment should be considered.

The aim of this study was to evaluate the effects of grape juice on colon carcinogenesis induced by azoxymethane (AOM) and expression of NF-kB, iNOS and TNF- α. Methods: Forty male Wistar rats were divided into 7 groups: G1, control; G2, 15 mg/kg AOM; G3, 1% grape juice 2 weeks before AOM; G4, 2% grape juice 2 weeks before AOM; G5, 1% grape juice 4 weeks after AOM; G6, 2% grape juice 4 weeks after AOM; G7, 2% grape juice without AOM. Histological changes and aberrant crypt foci (ACF) were studied, while RNA expression of NF-kB, TNF- and iNOS was evaluated by qPCR. Results: The number of ACF was higher in G2, and G4 presented a smaller number of crypts per focus than G5 (p=0.009) and G6. Small ACF (1-3) were more frequent in G4 compared to G2, G5 and G6 (p=0.009, p=0.009 and p=0.041, respectively). RNA expression of NF-kB was lower in G3 and G4 compared to G2 (p=0.004 and p=0.002, respectively). A positive correlation was observed between TNF- α and NF-kB gene expression (p=0.002). In conclusion, the administration of 2% grape juice before AOM reduced the crypt multiplicity, attenuating carcinogenesis. Lower expression of NF-kB was observed in animals exposed to grape juice for a longer period of time, regardless of concentration. Keywords: Grape juice - NF-kappa B - TNF-α - iNOS - carcinogenesis

Multidrug resistance (MDR) is a major impediment to successful chemotherapy of gastric cancer. Our aim was to establish an epirubicin-resistant cell subline (AGS/EPI) and to elucidate the mechanisms involved in acquired EPI resistance. The AGS/EPI cell subline developed by exposing parental AGS cells to stepwise increasing concentrations of EPI demonstrated 2.52-fold resistance relative to the AGS cell line, and mRNA expression of the ATP-dependent drug-efflux pump P-glycoprotein (Pgp), more recently known as ABCB1 protein, was similarly upregulated. An AGS/EPI cell subline could thus be effectively established, and MDR mechanism of these cells was shown to be related to the overexpression of mRNA of the ABCB1 gene.

Gastric cancer (GC) is one of the most common malignancies worldwide. The ABCB1 protein, a member of the ATP-binding cassette (ABC) transporter family, encoded by the ABCB1 gene, considerably influences the distribution of drugs across cell membranes as well as multidrug resistance (MDR) of antineoplastic drugs. In contrast to the extensive knowledge on the pharmacological action of ABCB1 protein, the correlation between the clinical-pathological data and ABCB1 protein expression in patients with GC remains unclear. The aim was to investigate association between ABCB1 expression and overall survival in GC patients. Human tumor fragments from 57 GC patients were examined by immunohistochemistry assay. We observed lower survival rate of patients with GC who were positive for ABCB1 expression (p=0.030). Based on these observations, we conclude that GC patients with positive ABCB1 protein immunohistochemical expression in their tumors suffer shorter overall survival.

Gastric cancer (GC) remains a virtually incurable disease when metastatic and requires early screening tools for detection of early tumor stages. Therefore, finding effective strategies for prevention or recurrence of GC has become a major overall initiative. RNA-interference (RNAi) is an innovative technique that can significantly regulate the expression of oncogenes involved in gastric carcinogenesis, thus constituting a promising epigenetic approach to GC therapy. This review presents recent advances concerning the promising biomolecular mechanism of RNAi for GC treatment.