HIF1A and neoplasm: Hypoxia-dependent HIF-1α and HIF-2α allow for the induction of numerous target genes regulating various biological processes of tumors, including angiogenesis, the epithelial-mesenchymal transition (EMT), maintenance of cancer stem cells (CSCs), metabolic reprogramming, tumor cell survival/proliferation, invasion/metastasis, and immune regulation [7, 16].