ERBB2 and urinary bladder neoplasm: Secondary loci found on chr9:22381987-23201516 and chr21:31405230-33951574 comprise many potential cancer genes, but two, Erb-B2 receptor tyrosine kinase 2 (ERBB2) and WEE1 G2 checkpoint kinase (WEE1), stand out as likely candidates for disease risk, as both are frequently mutated, amplified or dysregulated in human bladder tumors.