PKM and breast cancer: SPANX-A co-precipitates with specific enzymes that participate in glucose catabolism, such as pyruvate kinase (PKM), D-3-phosphoglycerate dehydrogenase (PHGDH) and pyruvate dehydrogenase E1 component subunit alpha (PDHA1), which have also been identified as oncogenes in malignant tumours not only in melanoma cells but also in colorectal or breast cancer cells32,33.