ARID1A and neoplasm: Importantly, ARID1A depletion or ARID1A truncating mutations did not sensitize urothelial cells to treatment with the small molecule EZH2-inhibitor GSK126, contrasting recent work using several tumor cell lines of different origin (lung, adrenal cortex, ovarian clear cell, endometrial, renal cell and rhabdoid carcinoma cells [21,22]) but excluding urothelial cells from their analyses.