Next, we examined the mutations in these genes in bladder cancer (Figure 5B) and found that the mutation frequency of PTGER4 was the highest, reaching 9%, with amplification mutations as the main mutation; it was followed by RUNX1, IL7, and CIITA, with mutation frequencies of 6, 5, and 5%, respectively. The gene discussed is PTGER4; the disease is urinary bladder cancer.