HIF1A and cancer: We have previously reported a cyclic peptide(cyclo-CLLFVY) that specifically inhibits the interactionof HIF-1αwith HIF-1β and disrupts HIF-1 activity in vitro and in cells.26 However, given the synergistic role played byHIF-1 and HIF-2 in cancer, a dual inhibitor of HIF-1 and HIF-2 wouldbe of value, both as a research tool and as a starting point for thedevelopment of a therapeutic agent.