RT Journal Article T1 Transfection with GLS2 Glutaminase (GAB) Sensitizes Human Glioblastoma Cell Lines to Oxidative Stress by a Common Mechanism Involving Suppression of the PI3K/AKT Pathway. A1 Majewska, Ewelina A1 Márquez, Javier A1 Albrecht, Jan A1 Szeliga, Monika K1 GLS2 glutaminase K1 PI3K/AKT signaling pathway K1 human glioblastoma K1 oxidative stress AB GLS-encoded glutaminase promotes tumorigenesis, while GLS2-encoded glutaminase displays tumor-suppressive properties. In glioblastoma (GBM), the most aggressive brain tumor, GLS is highly expressed and in most cases GLS2 is silenced. Previously, it was shown that transfection with a sequence encoding GAB, the main GLS2 isoform, decreased the survival, growth, and ability to migrate of human GBM cells T98G and increased their sensitivity towards an alkylating agent temozolomide (TMZ) and oxidative stress compared to the controls, by a not well-defined mechanism. In this study we report that GAB transfection inhibits growth and increases susceptibility towards TMZ and H₂O₂-mediated oxidative stress of two other GBM cell lines, U87MG and LN229. We also show that in GAB-transfected cells treated with H₂O₂, the PI3K/AKT pathway is less induced compared to the pcDNA-transfected counterparts and that pretreatment with PDGF-BB, an activator of AKT, protects GAB-transfected cells from death caused by the H₂O₂ treatment. In conclusion, our results show that (i) GAB suppresses the malignant phenotype of the GBM cells of different tumorigenic potentials and genetic backgrounds and (ii) the GAB-mediated increase of sensitivity to oxidative stress is causally related to the inhibition of the PI3K/AKT pathway. The upregulation of the GLS2 expression and the inhibition of the PI3K/AKT pathway may become a novel combined therapeutic strategy for anti-glioma preclinical investigations. SN 2072-6694 YR 2019 FD 2019-01-19 LK http://hdl.handle.net/10668/13443 UL http://hdl.handle.net/10668/13443 LA en DS RISalud RD Apr 11, 2025