KDR and neoplasm: In hypoxic environments, as in tumor tissues, hypoxia-inducible factor 1α (HIF-1α) is commonly induced, which activates both LDH-A, which is one of the LDH isozymes, and pro-angiogenesis factors such as vascular endothelial growth factor (VEGFA, VEGFR) via the same molecular pathway [22, 23].