ABSTRACT
Genetic and epigenetic inactivation of DNA mismatch repair (MMR) genes might lead to modifications in cancer-related gene expression and cancer development. Recently, it has been shown that the infection by Helicobacter pylori, the major causative agent of gastric cancer, induces DNA damage and inhibits MMR DNA repair. Also, it has been reported that microRNAs (miRs) have an important role in regulating genomic stability and MMR DNA repair. Thus, the aim of this study was to identify miRs regulating MMR pathway in H. pylori-associated gastric carcinogenesis. To address this question, a gastric epithelial cell line and AGS cancer gastric cells were infected with several H. pylori strains. MMR gene expression and miRs correlating with H. pylori strain infection were evaluated. The results showed that H. pylori infection significantly down-regulated the expression of all selected MMR genes. Also, H. pylori infection modulated the expression of several miRs (including miR-150-5p, miR-155-5p, and miR-3163), after 4, 8, and 12 h of infection. Computational prediction of candidate miRs and their predicted MMR targeting sites were obtained from TargetScan, mirDB, and MetaCore. The generated data indicated that the selected miRs (miR-150-5p, miR-155-5p, and miR-3163) could possibly target and modulate MMR genes (POLD3, MSH2, and MSH3, respectively). The target validation was performed using mimics and luciferase gene reporter assays. Briefly, this study shows that H. pylori impairs MMR DNA repair pathway and identifies miRs that regulate MMR gene expression in gastric cancer. © 2016 Wiley Periodicals, Inc.
Subject(s)
DNA Mismatch Repair , Helicobacter Infections/complications , Helicobacter Infections/genetics , Helicobacter pylori/physiology , MicroRNAs/genetics , Stomach Neoplasms/genetics , Stomach Neoplasms/microbiology , Stomach/microbiology , Cell Line , Cell Line, Tumor , Gastric Mucosa/metabolism , Gene Expression Regulation, Neoplastic , Helicobacter Infections/microbiology , HumansABSTRACT
We aimed to evaluate the in vitro effects of yerba maté, YGD (a herbal preparation containing yerba maté, guarana and damiana), and resveratrol on adipogenesis. The anti-adipogenic effects of yerba mate, YGD, resveratrol and YGD + resveratrol and yerba mate + resveratrol combinations were evaluated in 3T3-L1 cells by Oil Red staining, cellular triglyceride content, and PCR quantitative array. The results demonstrated that all of the tested compounds inhibited adipogenesis. Yerba maté extract significantly down-regulated the expression of genes that play an important role in regulating adipogenesis, such as Adig, Axin, Cebpa, Fgf10, Lep, Lpl, and Pparγ2. In addition, these genes, YGD also repressed Bmp2, Ccnd1, Fasn, and Srebf1. Resveratrol also modulated the expression of Adig, Bmp2, Ccnd1, C/EBPα, Fasn, Fgf10, Lep, Lpl, and Pparγ2. Moreover, resveratrol repressed Cebpb, Cdk4, Fgf2, and Klf15. The yerba maté extract and YGD up-regulated the expression of genes involved in inhibiting adipogenesis, such as Dlk-1, Klf2, and Ucp1. Resveratrol also induced the expression of Klf2 and Ucp1. In addition resveratrol modulated the Ddit3, Foxo1, Sirt1, and Sirt2. The combined effects of these compounds on gene expression showed similar results observed from individual treatments. Our data indicates that the synergy between the compounds favors the inhibition of adipogenesis.
Subject(s)
Adipogenesis/drug effects , Gene Expression Regulation/drug effects , Ilex paraguariensis/chemistry , Obesity/drug therapy , Plant Extracts/pharmacology , Stilbenes/pharmacology , 3T3-L1 Cells , Animals , Antioxidants/pharmacology , Biomarkers, Tumor/genetics , Biomarkers, Tumor/metabolism , Blotting, Western , Cell Differentiation/drug effects , Cell Proliferation/drug effects , Drug Combinations , Gene Expression Profiling , Mice , Obesity/genetics , Obesity/metabolism , Oligonucleotide Array Sequence Analysis , RNA, Messenger/genetics , Real-Time Polymerase Chain Reaction , Resveratrol , Reverse Transcriptase Polymerase Chain ReactionABSTRACT
Detailed chromosome maps with reliable homologies among chromosomes of different species are the first step to study the evolution of the genetic architecture in any set of species. Here, we present detailed photo maps of the polytene chromosomes of three closely related species of the tripunctata group (subgenus Drosophila): Drosophila mediopunctata, D. roehrae, and D. unipunctata. We identified Muller's elements in each species, using FISH, establishing reliable chromosome homologies among species and D. melanogaster. The simultaneous analysis of chromosome inversions revealed a distribution pattern for the inversion polymorphisms among Muller's elements in the three species. Element E is the most polymorphic, with many inversions in each species. Element C follows; while the least polymorphic elements are B and D. While interesting, it remains to be determined how general this pattern is among species of the tripunctata group. Despite previous studies showing that D. mediopunctata and D. unipunctata are phylogenetically closer to each other than to D. roehrae, D. unipunctata shows rare karyotypic changes. It has two chromosome fusions: an additional heterochromatic chromosome pair and a pericentric inversion in the X chromosome. This especial conformation suggests a fast chromosomal evolution that deserves further study.
