HIF1A and neoplasm: HPV contains an 8-kb circular genome which encodes for a number of proteins including viral “oncoproteins” E6 and E7 [91] which are responsible for the repression of host tumour suppressor genes TP53 and RB1. Increased viral E7 inhibits binding of HDACs to hypoxia inducible factor 1 (HIF-1), thus activating transcription of pro-angiogenic genes downstream of HIF-1 [93].