NRN1 and urothelial carcinoma: In order to develop the methylation assay for detecting urothelial carcinoma, we conducted a screening of 14 CpG sites in 7 genes (HIST1H4F, SOX1-OT, Vim, Onecut2, Twist1, NRN1, POU4F2) based on the literature review15,17–20.