To explore the tumorigenesis mechanism of miR-205 in human gastric cancer and their clinical significance

• Main Authors: Yi Da Lu, 盧奕達
• Other Authors: K. H. Lin
• Format: Others
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/23873285033610484412

碩士 === 長庚大學 === 生物醫學研究所 === 100 === Gastric cancer (GC) is the second leading cause of cancer-related death in the worldwide and the sixth in Taiwan . The tumorigenesis of GC is still unknown, and we are still search for the new biomarker to increase patients survival rate. Recent research indicate that microRNAs could negative regulate the target gene by binding to the 3’UTR of the target gene and inhibit the transcription or translation. microRNAs play important role in not only development and differentiation but tumorigenesis. Preview qRT-PCR profiling of 270 cancer related miRNAs in 6 pair gastric cancer clinical samples indicated that miR-205 was 2.41 time up-regulated in tumor with statistical significance(3-way-ANOVA , Ct<35, p<0.05, 1.5 fold change). In this study, miR-205 was selected as the candidate gene, which were up-regulated in 76.9% of clinical specimens in 52 pair samples, and statistical significantly with the TNM stage. We assumed that miR-205 may played as an onco-miR and correlated with tumor progression in GC. To investigate the biological function of miR-205, we used the lentiviral expression system to establish stable cell lines that were in vitro over-expressed or knocked down of miR-205. And the result indicated that miR-205 would promote cell migration in GC. To search for the potential target gene of miR-205, we correlated our preview iTRAQ database with online database (miRBase) and found Glutathione-s-transferase mu 1 (GSTM1). We validated that GSTM1 could negative regulated by miR-205 using 3’UTR luciferase reporter assay and western blot. In addition, in order to investigate whether GSTM1 could regulate cell migration in GC, we used shRNA to establish GSTM1 knocked down stable cell line and found out that GSTM1 could inhibit cell migration. The data suggest that GSTM1 played as a tumor suppressor. These results indicated that GSTM1 was one of the target gene that regulated by miR-205 to regulate the tumorigenesis of GC.