Expression analysis of miR-200a-3p, miR-223-5p AND miR-29a-3P miRNA in polymorphic Helicobacter pylorium vaca genotypes in gastric cancer

Gastric cancer is a type of cancer with a high incidence and mortality. It is the second largest cancer-related mortality in the global dimension. H. pylori is known as a stomach cancer risk factor. A vacuole-forming protein is released from H. pylori. It is known that the vacuole forming protein is encoded by the gene called VACA. The protein encoded by VacA is 140 kDa in size as a precursor. Proteolytic processes from secreted proteins result in an active toxin region of 88 kDa. The active toxin region comes from the two ponds called p33 and p55. There are s-, m- and i- regions on these two arms. In H. pylori vacA toxin regions there are forms containing different alleles (S1 / M1 / i1 or S2 / M2 / I2). The S1 / M1 / Il alleles are the most polymorphic forms. There is a direct relationship between the ability of H. pylori vacA to form vacuole and other effects such as apoptosis triggering and suppression of T lymphocyte proliferation. H. pylori virulence factor VacA has been found to alter many miRNA expressions, including let-7. In this study, PZR analysis was performed to detect polymorphic regions of VacA gene in H. pylori strains isolated from stomach cancer tissues. Expression changes of miR-29a-3p, miR-200a-5p and miR-223-3p miRNAs in cancerous stomach tissues with different VacA forms were analyzed by quantitative real-time PZR. It was observed that different VacA forms may affect the expression level of miRNAs studied in stomach cancer tissues.