HIF1A and neoplasm: Hypoxia induces radioresistance [68]; triggers the migration and invasion ability of tumours [69], also through the production of circulating tumour cells (CTCs); and induces the production of hypoxia-inducible factors (HIF), such as HIF-1, which controls the expression of genes and pathways impacting metabolism, angiogenesis, and cell growth, differentiation, survival, and death [70,71].