HIF1A and neoplasm: Red propolis produces antioxidant effects, inhibits angiogenesis through modulation of angiogenic factors and inflammation, and reduces the levels of vascular endothelial growth factor (VEGF) and hypoxia-inducible factor (HIF)-1α.(23,24) Also extensively documented is the relation between angiogenesis, oxidative stress and tumor hypoxia.(25) The correlation between the antiangiogenic and antioxidant effects of propolis was evaluated in vitro using endothelial cells; unsurprisingly, the most antiangiogenic compounds were also the most antioxidant.(26)