MicroRNA-142-3p suppresses cell proliferation and migration in bladder cancer via Rac1

Expression of microRNA(miR)-142-3p has been implicated to be associated with several cancers, whereas its function in bladder cancer (BC) remains unknown. The present study aimed to explore the correlation between the expression of miR-142-3p and the proliferation, migration and invasion of bladder cancer cells by activating Rac1. qRT-PCR was used to measure the expression of miR-142- 3p in bladder cancer tissues and cell lines. RNA transfection was used to silence and accelerate the expression of miR-142-3p in bladder cancer cells. CCK-8 and trans-well assays were used to detect the proliferation, migration and invasion of cells before and after RNA transfection. The direct interaction between Rac1 and miR-142-3p was demonstrated by a dual luciferase reporter assay. qRT-PCR and Western blot assays were used to detect the expression changes in Rac1 before and after transfection. The results showed that miR-142-3p in bladder cancer tissues was significantly lower than that in adjacent tissues and lower than that in HT1376 and T-24 cells but higher than that in T5637 and BIU- 87 cells. Additionally, upregulating miR-142-3p expression not only inhibits the proliferation of SV-HUC-1 and BIU-87 cells but also inhibits migration and invasion, and downregulating miR-142-3p expression showed the opposite results. The expression of Rac1 was promoted after stimulating miR- 142-3p expression, but was inhibited after silencing miR-142-3p expression. In conclusion, miR-142-3p affects the proliferation, migration and invasion of bladder cancer cells by regulating Rac1.