PKM and neoplasm: Interestingly, hypoxic conditions have been found to drive the glycolytic activity of tumor-associated fibroblasts (CAF) through capillary dilatation ataxia mutated (ATM) oxidation, glucose transporter protein 1 phosphorylation, and PKM2 overexpression, and that lactic acid produced by CAF is ultimately used to drive breast cancer cell invasion through activation of the TGF1/p38 MAPK/MMP2/9 signaling axis and promotion of mitochondrial oxidative phosphorylation (57, 58).