A recent report had demonstrated this in bladder cancer cells [33], and in the publicly accessible TCGA dataset we found a moderate correlation of CXCL9 and PD-L1 expression, suggestive of possible interaction (r = 0.58 (Pearson); P < 0.0001; Fig. 4a). This evidence concerns the gene CXCL9 and urinary bladder carcinoma.