| First Author | Xie S | Year | 2020 |
| Journal | Cell Rep | Volume | 32 |
| Issue | 13 | Pages | 108196 |
| PubMed ID | 32997991 | Mgi Jnum | J:301246 |
| Mgi Id | MGI:6489144 | Doi | 10.1016/j.celrep.2020.108196 |
| Citation | Xie S, et al. (2020) Divergent Roles of PI3K Isoforms in PTEN-Deficient Glioblastomas. Cell Rep 32(13):108196 |
| abstractText | Loss of PTEN, the negative regulator of PI3K activity, is frequent in glioblastomas (GBMs). However, the role of the two major PI3K isoforms, p110alpha and p110beta, in PTEN-deficient gliomagenesis remains unknown. We show that PTEN-deficient GBM largely depends on p110alpha for proliferation and p110beta for migration. Genetic ablation of either isoform delays tumor progression in mice, but only ablating both isoforms completely blocks GBM driven by the concurrent ablation of Pten and p53. BKM120 (buparlisib) treatment only modestly prolongs survival in mice bearing intracranial Pten/p53 null tumors due to partial pathway inhibition. BKM120 extends the survival of mice bearing intracranial tumors in which p110beta, but not p110alpha, has been genetically ablated in the Pten/p53 null glioma, indicating that BKM120 fails to inhibit p110beta effectively. Our study suggests that the failure of PI3K inhibitors in GBM may be due to insufficient inhibition of p110beta and indicates a need to develop brain-penetrant p110alpha/beta inhibitors. |
