In line with this, the lactate levels increased both in tumor and peritumoral tissues, as well as the expression of glutamine transporters (i.e., SLC1A5) and glycolytic enzymes, such as glucose-6-phosphate isomerase (GPI), phosphoglycerate kinase (PGK1), aldolase A (ALDOA) and hexokinase 2 (HK2) (Figure 6). Here, PGK1 is linked to neoplasm.