ARID1A and urinary bladder cancer: Next, we investigated the somatic mutations of DEGs between the two clusters and identified mutations in top 20 genes, such as TP53, TIN, KMT2D, MUC16, KDM6A, ARID1A, PI3KCA, SYNE1, and RB1, which were considered to be important in immunotherapy and tumor development of bladder cancer (Figure 3B).