PIK3R3 and urinary bladder cancer: To determine if PIK3R3 upregulation in ARIDA-deficient (ARID1Adef) cells is specific to bladder cancer, we performed an in silico meta-analysis focused on the differential expression of PI3KR3 in all publicly available transcriptomic data sets comparing ARID1A-deficient and WT cells (see Supplemental Figure 8 for accession numbers).