P07.06.B POLYMER-LOCKING FUSOGENIC LIPOSOMES FOR GLIOBLASTOMA-TARGETED SIRNA DELIVERY AND CRISPR-CAS GENE EDITING

Abstract BACKGROUND Glioblastoma (GBM) is the most lethal central nervous system cancer, with poor prognosis and high resistance to therapies like temozolomide (TMZ). The upregulation of midkine (MDK) in GBM cells accelerates DNA repair, limiting TMZ’s effectiveness. RNAi and CRISPR-Cas9 offer potential solutions by targeting MDK, but delivering these biologics across the blood-brain barrier (BBB) and into GBM cells is challenging. Existing methods struggle with low endo-lysosomal escape rates and BBB penetration. To address this, we developed polymer-locking fusogenic liposomes (Plofsomes) that can cross the BBB and deliver siRNA or CRISPR-Cas9 complexes specifically to GBM cells, enhancing therapeutic efficacy and safety. RESULTS 结果: 1. In Vitro and In Vivo Delivery: Plofsomes effectively delivered siRNA and CRISPR-Cas9 RNP complexes into GBM cells, with higher delivery efficiency in high ROS environments.2.Suppression: Plofsome@siMDK significantly reduced MDK expression (P < 0.0001) in GBM cells and tumors.3. Antitumor Efficacy: Plofsome@siMDK + TMZ treatment inhibited tumor growth by 40% and increased survival rate to 40.0% in mouse models.4. Safety and Specificity: Plofsomes were non-toxic and did not affect MDK expression in normal tissues.5. Mechanistic Insight: MDK interacts with CD109 to enhance TMZ resistance; Plofsome@siMDK disrupted this interaction, reducing DNA repair and tumor proliferation. CONCLUSION We developed Plofsomes, a nanotechnology platform that delivers siRNA and CRISPR-Cas9 RNP complexes across the BBB and into GBM cells. By integrating a ROS-cleavable ‘lock’, Plofsomes ensure targeted fusion and cargo release in high ROS tumor environments. Our findings show Plofsomes effectively suppress MDK expression, reducing TMZ resistance and inhibiting GBM growth in models. This enhances the efficacy and safety of RNAi and CRISPR-Cas9 therapeutics. The study provides insights into TMZ resistance mechanisms and the role of MDK in GBM progression. Plofsomes offer a promising strategy for improving GBM treatment outcomes and could impact future research and patient care.