PSPH and glioblastoma: As expected, the depletion of AMPK expression or compound C treatment resulted in impaired S/G deprivation-induced mRNA and protein expression levels of PHGDH, PSAT1, and PSPH (Fig. 5I and J, and Fig. S5E and F of the SI), as well as mRNA expression levels of GLUT1, GLUT 3, HK2, and PFKFB2 (Fig. 5K) in GBM cells.