PPARGC1A and glioblastoma: Our Western blotting data (Figure 6A,B) showed that metformin tended to significantly decrease levels of both PGC-1α and mtTFA proteins in U87MG, LNZ308, and LN229 cells, suggesting that ROS production, membrane potential, and biogenesis might be disrupted in the mitochondria of metformin-treated GBM cells.