XIST and urinary bladder cancer: TCC-SUP and UM-UC-3 cell lines showed an increase in miR-124 expression and a decrease in AR expression in response to XIST knock down, but in the presence of XIST, a decrease in miR-124 expression is observed and an increase in AR expression level; these data suggest that miR-124 functions as a tumor suppressor of bladder cancer by a regulation of the AR, and XIST serves as a sponge of miR-124, restoring the AR proliferative activity [65,66].