Molecular Subtyping of Bladder Cancer

In TCGA cohort, we obtained the molecular classification information of patients using R package ‘BLCAsubtyping’ (2.1). In ZS cohort, we performed IHC single staining of KRT5/6 (1:25 dilution, Abcam, ab17133) and GATA3 (1:100 dilution, Abcam, ab199428) to classify patients into either basal or luminal subtype in ZS cohort according to an IHC subtyping method reported in a previous article.18 (link) KRT5/6 is considered as a basal marker, while GATA3 is highly expressed in luminal subtype. During IHC evaluation, KRT5/6 and GATA3 expression were assessed as either negative or positive, the cut-off point of which was defined as 20% tumor tissue positivity under 200× high power field.18 (link) KRT5/6⁺GATA3^- tumors were classified as basal subtype, while the rest were classified as luminal subtype.