HMOX1 and neoplasm: In NMIBC bladder cancers, HO-1 expression in tumor mass correlates with HIF-1α expression and microvessel density [123], and in particular, Nrf2 and HO-1 positivity correlates with HIF-1α, HIF-2α, and VEGF expression in the tumor, and with VEGF and interleukin levels in the plasma [124].