HIF1A and neoplasm: Inhibitors of HIF dimerization include cyclic CLLFVY that binds the HIF-1α PAS-B domain disrupting dimerization, transcriptional function and hypoxic response in tumour cells [279], TC-S7009 [280], an unreferenced small molecular PT2353 nanomolar HIF-2 but not HIF-1 inhibitor that impairs HIF DNA-binding and HIF-2 dependent hypoxic responses, and the antiseptic dye acriflavine that inhibits HIF-1 and HIF-2 and prevents HIF-1 dimerization [281].