HK2 and glioblastoma: Furthermore, exposure to IGFBP6 for 24 h in GBM cells resulted in a significant increase in lactate dehydrogenase A (LDHA) mRNA levels in U-87 MG (1.75 ± 0.15, Fig. 3D), A-172 (36.9 ± 3.9, Fig. 3F) and U-251 MG (27.2 ± 3.2, Fig. 3H) compared to their control cells, a significant increase in hexokinase 2 (HK2) mRNA expression levels in all three cell lines (Fig. 3D–H), and a significant increase in Enolase 1 (ENO1) mRNA expression levels only in U-87 MG and A-172 cells but not in U-251 MG (Fig. 3D–H).