Functional genetic screens to uncover the roles of chromatin modifiers in IDH-mutant glioma

Gliomas, a malignant group of central nervous system tumors, pose a significant health threat, particularly grade IV glioblastoma, which is the most aggressive type. Among gliomas, IDH-mutant gliomas exhibit a more favorable response to therapies, making them an intriguing target for precision treatments. This thesis delves into the investigation of essential epigenetic modifiers that may underlie vulnerabilities in IDH-mutant gliomas using a custom designed CRISPR-Cas9 epigenetic library called EPIKOL. In the first part of the thesis, IDH-wildtype and IDH-mutant cells were generated from the A172 glioma cell line. Subsequently, CRISPR-Cas9 mediated screening with the EPIKOL library was performed on these cell lines to identify epigenetic modifiers that are essential for IDH-wildtype and/or IDH-mutant glioma cells. The candidates were then validated through functional in vitro assays, focusing on cell viability and colony formation ability. Among the validated genes, RBBP7, which plays a role in complexes involved in histone modification and gene expression regulation, emerged as a potential essential regulator of IDH-mutant glioma cells. Overall, the findings from this study lay the foundation for identifying novel therapeutic targets for IDH-mutant glioma through further experiments and analyses. Future work will dissect out the gene regulatory function of RBBP7 in IDH-mutant cells using RNA sequencing. The investigation of essential epigenetic modifiers offers promising avenues for precision treatments in combating this challenging form of brain tumor.