NNMT and benign prostatic hyperplasia: While the majority of BPH cases (18/26; 69.2%) exhibited absent or extremely weak NNMT expression, NNMT was significantly upregulated in the HGPIN (15/18; 83.3%) and PCa (77/120; 64.2%) tissues, when using an IR score of 4 as a cutoff (Figs. 1 and 2A).