SIRT4 and urinary bladder carcinoma: To investigate the functional roles of miR-424-mediated down-regulation of UNC5B and/or SIRT4 in CDDP-induced apoptotic cell death of bladder cancer cells, siRNA-mediated gene silencing of UNC5B and SIRT4 was performed in T24 and 5637 cells (Fig. 4a).