Effect Of MicroRNA-200c To ZEB1 Expression And To Migaration And Invasion Ability Of Tumor Cell

MicroRNAs (miRNAs) are an newly found conserved group of small endogenous non-coding RNAs involved in posttranscriptional gene repression. They can specifically bind to 3' UTR of target mRNA, leading to either degradation of mRNA or inhibition of translation. They were confirmed to be involved in diverse biological response in eukaryote organism, such as growth, tissue differentiation, signal transduction, metabolism, disease and death. They were also proved to be related to the generation and development of tumor cells, although the mechanism is not clear.ZEB1(zinc-finger E-box binding homeobox 1) also called TCF8 orδEF1, can negtively control kinds of gene expression in several cell lines, such as IL-2,p73,GATA-3,collagenⅠ/Ⅱand so on. It can also promote the migration and invasion ability of tumor cells by repressing the expression of E-cadherin. ZEB1 and microRNA-200c can repress each other forming a feedback mechanism to regulate the invasion and metabasis ability in tumor cells.To verify if this feedback mechanism also function in gastric cancer and other tumor cells, we detected the expression level of ZEB1, invasion and migration ability of several tumor cells to observe the relationship of them. By up-regulating miR-200c levels in SGC7901 cell we observed the biological behaviour changes of SGC-7901 cell, offering new methods for tumor therapy. Our study including two parts:1. We chose four common malignant tumor cells BGC-823,SGC-7901,A549 and HeLa, gastric mucosa cell GES-1 as control, using Real-time PCR to detect ZEB1 expression level of the cell lines. The cell migration and invasion ability were performed by Transwell test. We found that the ZEB1 expression level with the migration and invasion ability was positive correlation, indicated that ZEB1 expression level was correlated with migration and invasion ability of tumor cells.2. We transfected SGC-7901 cells with synthesized microRNA-200c, accompanied with blank transfection group and independent sequence transfection group, 24 h after transfection, we used Real-time PCR to detect the ZEB1 expression level of each transfection group. Transwell test was used to detect the migration and invasion ability changes after the transfection. The results showed that the migration and invasion ability of SGC-7901 cells were significantly repressed by transfection of microRNA-200c.Our study indicated that the ZEB1 expression level was correlated with the migration and invasion ability of the four tumor cell lines. Transfection of microRNA-200c could repress the expression level of ZEB1 and then suppress the migration and invasion ability of SGC-7901 cell.