PFKFB3 and neoplasm: Tumor cells often express high levels of the glycolytic enzymes hexokinase 2 (HK2) and 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3 (PFKFB3), or switch isoforms of metabolic enzymes such as PKM (Alves-Filho and Pålsson-McDermott, 2016; Lincet and Icard, 2015).