PKM and breast cancer: Recent investigations have revealed that in BC cells under hypoxic conditions, nuclear PKM2 recruits HIF-1α and p300, leading to the upregulation of 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 3 (PFKFB3), an enzyme involved in glycolysis that is associated with cancer progression and aggressiveness (36).