To date, GCN5‐related N‐acetyltransferase 10 (NAT10) is the only known ac4C‐catalyzing enzyme.[6a–c] Studies have found that various mRNAs are acetylated by NAT10 in diverse cell types and across species, which further upregulates their protein levels, including COL5A1 in gastric cancer cell metastasis[8a] and AHNAK in DNA damage repair response against chemotherapy in bladder cancer.[9] The lack of NAT10 hinders cell proliferation and migration but does not affect cell viability.[6, 10] Germ cell‐specific knockout of Nat10 mouse resulted in sterility in both genders. Here, NAT10 is linked to urinary bladder cancer.