GGT5 and glioblastoma: ACADL mediates fatty acid oxidation, which protects against ferroptosis (29), a finding consistent with our lipidomic findings (Figure 2E), and GGT5 hydrolyzes glutathione before it is recycled to cysteine, a potential response to the increased flux through the transsulfuration pathway suggested by the increased cystathionine identified in our metabolomic analysis of invasive GBM cells (Figure 1C).