[Mir-29c-3p targeting TUG1 affects migration and invasion of bladder cancer cells by regulating CAPN7 expression]

Objective: To investigate the mechanism by which long non-coding RNA TUG1 affects bladder cancer cell migration and invasion.

Methods: The expressions of TUG1 and miR-29c-3p were examined by quantitative RT-PCR (qRT-PCR) in 10 bladder cancer tissues and 5 bladder cancer cell lines. Trans-well assay was used to detect the changes in migration and invasion abilities of bladder cancer T24 cells after TUG1 knockdown using RNA interference technique, and the alteration in the expression of CAPN7 was also detected. The expression of CAPN7 was examined in T24 cells overexpressing mir-29c-3p by Western blotting, and luciferase reporter assay was performed to confirm the targeting of miR-29c-3p to TUG1 and CAPN7. The effects of CAPN7 overexpression and sh-TUG1 on the migration and invasion of T24 cells were investigated.

Results: The expression of TUG1 was up-regulated and mir-29c-3p was down-regulated significantly in bladder cancer tissue with a negative correlation between their expressions. TUG1 knockdown significantly inhibited the migration and invasion of T24 cells (P < 0.01). Overexpression of mir-29c-3p in T24 cells obviously down-regulated the expression of CAPN7 protein, whose expression was positively correlated with TUG1 expression (r=0.4081, P=0.0139). The results of luciferase reporter assay confirmed both TUG1 and CAPN7 as the targets of mir-29c-3p. CAPN7 overexpression could partially reverse the tumor suppressing effect of sh-TUG1 in T24 cells.

Conclusions: Mir-29c-3p targeting TUG1 affects the migration and invasion of bladder cancer cells by regulating the expression of CAPN7.