PDK1 and neoplasm: It remains to be elucidated what other factors might be involved in the hypoxic response; furthermore, AMPK, ERK, and JNK pathways are involved in the regulation of metabolic reprogramming in tumour cells, and it has been shown that hypoxia-driven phosphorylation of ERK1-2 influences TCA flux by activation of PDK-1 and the consequent inhibition of PDH [63].