HK2 and hepatocellular carcinoma: Under normoxic conditions, both palbociclib and regorafenib as well as their combination down-regulated the expression of hexokinase 2 (HK2), the major HK isoform expressed in HCC (44), and phosphofructokinase platelet (PFKP), a major isoform of PFK-1 controlling the first rate-limiting step of glycolysis in cancer cells (45) (Figure 7C).