In five bladder cancer datasets (TCGA-MIBC, GSE13507, GSE48075, GSE32894, and GSE48276), ERBB2 was highly positively correlated with GATA3 and FOXA1 but negatively correlated with CD44 and KRT5, suggesting that ERBB2 is a luminal marker to some extent (Supplementary Figures S4A–E). This evidence concerns the gene CD44 and urinary bladder cancer.