HIF1A and neoplasm: Selective genetic or pharmacological inhibition of eNOS or iNOS or enzymatic induction of NO deficiency in tumor cells diminishes VEGF, HO-1, and HIF1α activation and consequent tumor cell proliferation and angiogenesis (Kimura et al., 2000; Motterlini et al., 2000; Naughton et al., 2002; Kasuno, 2004).