A Preliminary Study Of MicroRNA-141、microRNA-205、microRNA-429in The Invasion And Metastasis Of Bladder Cancer

Objective:The aim is to investigate the difference in microRNA expression pattern between superficial and invasive bladder cancer tissues and study the biologic role of microRNA in the invasion of bladder caner cells, thus, it may direct new diagnostic indications and therapeutic interventions in this disease.Methods:25cases of superficial bladder cancers and20cases of invasive bladder cancers confirmed by H&E staining were employed to study the expression pattern of miR-429, miR-141and miR-205by using realtime-PCR..The in vitro invasion and microRNA expression in different bladder cancer cell lines with different invasive potentials were analysized by using Transwell invasion assay and realtime-PCR. The cell which had a high invasive potential but with a decreased microRNA expression was subjected to transfection with microRNA-overexpression plasmid and the changes in invasive ability was then measured by Transwell invasion assay to study the effect of microRNA on cell mvasion.Results:1. There was no significant difference in the expression of miR-429and miR-141between superficial and invasive bladder cancer tissues (P>0.05). However, invasive bladder cancer tissues showed a decreased expression of miR-205compared to superficial bladder cancer tissues (P <0.05), the expression level of miR-205in invasive bladder cancer tissues was0.4times of superficial bladder cancer tissues.2. There were significant differences in both the invasion abilities and the expression levels of miR-205between bladder cancer T24cell and5637cell (P<0.001). T24showed a higher (4times) invasion ability but a lower (0.134times) expression level of miR-205then5637cell.3. Over-expressing miR-205plasmid could significantly inhibit the invasion of T24cells (P<0.05) in vitro which was only0.48times to the control vector transfected cells.Conclusion:1. Invasive bladder cancer tissues show a much different pattern in the expression of microRNA with superficial bladder cancer tissues, abnormal expression of microRNA in invasive bladder cancer would be the key event during the invasion of bladder cancer.2. miR-205, but neither miR-429nor miR-141, may involve in the invasion of bladder cancer cells, which could function as a suppressor in the invasion of bladder cancer.