IGF1 and neoplasm: The mechanisms of action of vitamin D include inhibition of VDR-mediated IGF1, HIF1, NF-κB and PI3K/AKT activities, or activation of MAPK family-related genes, downregulation of cell cycle progression, anti-inflammation, inhibition of angiogenesis, induction of apoptosis, and other anti-tumor effects (Skrajnowska and Bobrowska-Korczak, 2019).