LDHA and cancer: Like most cancers, MM cells show an increased glycolic flux (Figure 1A) (19), which is sustained by increased expression of glucose transporters (GLUTs) (36) and glycolytic enzymes such as hexokinase 2 (HK2) (37, 38), phosphofructokinase (PFK) (39), pyruvate kinase M2 (PKM2) (40–42), pyruvate dehydrogenase kinase 1 (PDK1) (43, 44) and lactate dehydrogenase A (LDHA) (43, 45).