Data mining TCGA expression data for urothelial and prostate lineage markers, this study establishes that in descending order of importance, genes for uroplakin II, S100P, GATA3 and thrombomodulin are the most important urothelial lineage markers to distinguish a carcinoma as bladder urothelial carcinoma from prostate adenocarcinoma. This evidence concerns the gene UPK2 and prostate adenocarcinoma.