SUV39H1 Maintains Cancer Stem Cells in Glioblastoma [ATAC-seq]

Glioblastoma (GBM) is the deadliest brain cancer, driven in part by GBM stem cells (GSCs) that contribute to therapeutic resistance and tumor recurrence. Effective targeting and elimination of GSCs hold promise for preventing GBM recurrence and achieving potential cures. In this study, we explored the role of the epigenetic regulator SUV39H1 in GSC maintenance and GBM progression. We observed that SUV39H1 is upregulated in GBM samples compared to normal brain tissues. Single-cell RNA-seq data indicated that SUV39H1 is preferentially expressed in GSCs relative to non-stem GBM cells, possibly due to super-enhancer-mediated transcriptional activation. Knockdown of SUV39H1 in patient-derived GSCs impaired their proliferation and stemness. RNA-seq analysis revealed that SUV39H1 regulates G2/M cell cycle progression, stem cell maintenance, and cell death pathways in GSCs. Integrated ATAC-seq (assay for transposase-accessible chromatin followed by sequencing) and RNA-seq analyses demonstrated that targeting SUV39H1 altered chromatin accessibility in key genes associated with these pathways. Treatment with chaetocin, a SUV39H1 inhibitor, mimicked the effects of SUV39H1 knockdown in GSCs and sensitized them to the GBM chemotherapy drug temozolomide (TMZ). In vivo studies using an intracranial patient-derived xenograft model showed that targeting SUV39H1 inhibited GSC-driven tumor formation in mice. Our findings identify SUV39H1 as a critical regulator of GSC maintenance and suggest that targeting SUV39H1 could disrupt GSCs and enhance the efficacy of existing chemotherapy, offering a promising strategy for improving GBM treatment outcomes.