Still, Foxa1 KO was induced relatively early (3 months of age in experiments using UBC-CreERT2, embryonic day 12 for Upk2-Cre) in all experiments, and perhaps Foxa1 KO would fail to reduce urothelial hyperplasia/tumor burden following prolonged HRAS* expression because of enhanced genetic instability. This evidence concerns the gene UPK2 and neoplasm.