홍지원 (고려대학교)

이상원 (고려대학교)

홍지원 (고려대학교)

이상원 (고려대학교)

​Glioblastoma multiforme (GBM) is an malignant cancer primarily known to occur in the brain or spinal cord. Interestingly, genome-wide mutational analyses have identified IDH1 mutation, which is a frequent alteration seen in GBM, to be associated with improved patient survival. However, the technical challenges involved in establishing stable IDH1-mutant cell lines have historically limited comprehensive proteomics studies despite its great interest and impact. In this study, we successfully generated U-87 glioma cell lines harboring the IDH1 R132H point mutation, which enabled performing in-depth global and phosphoproteomic profiling to investigate of the mutation’s impact on GBM progression. Early and late states of U-87 IDH1 WT and MT cells were analyzed using triplicate 6-plex TMT-labeled peptide sets.

Proteome profiling using a DO-NCFC-RP/RP-MS/MS platform yielded an average of 259,061 distinct peptides corresponding to 11,868 protein groups from global proteome analysis. 51,595 distinct phosphopeptides with 41,603 phosphorylation sites, corresponding to 7,352 phosphoprotein groups were identified from the enriched phosphoproteome dataset. With our extensive datasets, we performed gene ontology enrichment analysis and integrated RNA-seq transcriptome data to identify overlapping differentially expressed proteins and genes between IDH1 WT and MT conditions.

This overlap was compared with GBM mesenchymal subtype specific signature genes obtained from TCGA mRNA-seq dataset and microarray data of TMZ treated GBM patients leading to 12 core genes taken for network model construction. Our integrative analysis suggests alteration of TGF-beta signaling and DNA damage response pathways with the presence of IDH1 mutation, suggesting its role in the observed prolonged survival, offering potential insights for future GBM treatment strategies.