In the Oncomine database, lower XDH mRNA expression was detected in bladder cancer, breast cancer, colorectal cancer, leukemia, liver cancer, and lymphoma (Fig. 1A), while higher mRNA expression of XDH was observed in head and neck cancer (HNSC) and lung cancer in some datasets compared to that in normal tissues. This evidence concerns the gene XDH and urinary bladder carcinoma.