HIF1A and neoplasm: In hypoxia, the blockage of proline hydroxylation due to the inactivation of prolyl hydroxylase (PHD) and factor inhibiting HIF‐1 (FIH‐1) prevents the hydrolysis of HIF‐1α, inducing activation of HIF‐1 to affect the expression of VEGF, which drives tumor cell proliferation.32, 33, 34