The expression level changes of microRNAs 200a/205 in the development of invasive properties in gastric cancer cells through epithelial-mesenchymal transition.

EMT (Epithelial-Mesenchymal Transition) is a highly regulated process that results in cancer progression. MicroRNA plays a significant role in the regulation of EMT through tight control of the transcription factors. In this study, we focus on miR-200a/205 as a factor involved in the control of the EMT process in gastric cancer cells. In this sense, gastric adenocarcinoma cell lines were used to induce EMT process. For characterization of EMT process, the mRNA levels of E-cadherin, Vimentin, β-catenin, ZEB1 and Snail were measured by real time PCR. In addition, Western blot approach was adopted to determine the protein levels of these EMT markers. Transwell assay revealed migration and invasion property of gastric cancer cell after EMT induction. To analyze alteration amount of microRNAs, RT-PCR was applied. Our results confirmed the establishment of in vitro EMT model. In vitro study showed a significant negative correlation between the expression of miR-200a (P = 0.001) and expression level of EMT markers. Nevertheless, miR-205 did not show any significant results in correlation with EMT in AGS cell line. All in vitro results also were validated in gastric cancer tissue samples. Based on our findings from gastric cancer sample patients and in vitro results, miR-200a is down regulated. Therefore, in further investigation, miR-200a could be used as a candidate to prevent the invasive properties of gastric cancer through the EMT process.