In our previous works, we reported an enhanced expression of NNMT in numerous cancers, such as renal cell carcinoma (ccRCC) [23], oral squamous cell carcinoma (OSCC) [11], bladder urothelial carcinoma [9], non-small cell lung cancer (NSCLC) [24], and skin malignancies [8, 25]. Here, NNMT is linked to bladder transitional cell carcinoma.