DIA-MS proteomics of untreated and TAT-Cx43266-283-treated G166 GSCs

Glioblastoma (GBM) is the most frequent and aggressive primary brain cancer. Our studies have shown that the Src inhibitor, TAT-Cx43266-283, exerts antitumor effects in different preclinical models of GBM, including fresh specimens from GBM patients, and enhances survival in glioma-bearing mice. Because addressing TAT-Cx43266-283 mechanism of action is essential to translate these results to a clinical setting, in this study we carried out an unbiased proteomic approach in human glioblastoma stem cells (GSCs). Data-independent acquisition mass spectrometry proteomics allowed the identification and quantification of 6,561 proteins, of which 190 were modified by TAT-Cx43266-283. Our results are consistent with the inhibition of Src as the mechanism of action of TAT-Cx43266-283 and unveils additional crucial proteins. Altogether, this study expands the knowledge about the mechanism of action of TAT-Cx43266-283, providing a rationale for therapy combination and supporting its use in GBM clinical trials.