SCIDOT-40. THERAPEUTIC GENOME EDITING AS A NOVEL TREATMENT FOR GBM

Abstract Glioblastoma multiforme (GBM), is the most aggressive form of glioma, a brain tumor that arises from glial cells. GBM is considered a complex malignancy with multiple gene mutations, aberrations, and overexpression together with high infiltration rate and resistance to apoptosis. The current treatment consists of surgical resection, aggressive radiation and chemotherapy regimen. This therapeutic strategy had not changed since 2005 when the chemotherapy Temozolomide was approved. This therapeutic approach extended GBM patients’ life expectancy to approximately 15 months since diagnosis. Although recent progress in genomics and proteomics has paved the way for identifying potential therapeutic targets for treating GBM, the majority of these leading drug candidates remain ineffective. Therefore, novel and effective treatment to GBM presents an unmet need. Lipid nanoparticles (LNPs) are the most clinically advanced delivery platform to date for systemic administration of RNA therapeutics, with the recent approval of Patisiran, siRNA encapsulating LNPs. In recent years, several gene editing technologies have been discovered in bacteria, enabling precise and permanent manipulations at the DNA level. The most advanced and versatile system is based on the CRISPR nuclease Cas9. The recognition of its target chromosomal DNA by Cas9 results in a site-specific double-strand break (DSB), that eventually results in gene disruption. This approach opens multiple venues for research and treatment of diseases including cancer. We have utilized CRISPR encapsulating LNPs to promote a therapeutic gene editing by disrupting key GBM survival genes in vitro in murine and human GBM cell lines as well as in vivo in an aggressive syngeneic GBM mouse model. Our results suggest that treatment with our LNPs based system can specifically and efficiently target GBM cells in vitro and in vivo. Our CRISPR-LNPs based platform could potentially mature to a clinical trial, and ultimately might become a new therapeutic modality in GBM.