Abstract 59: LNP-CRISPR Gene Editing Enables in Vivo ATAD3A Depletion and Induces the Remission of Head and Neck Cancer

Abstract

Abstract Purpose: Targeting mitochondrial oncoproteins presents a new concept in developing effective cancer therapeutics. ATAD3A, a nuclear-encoded mitochondrial enzyme, represents a promising target for combating head and neck squamous cell carcinoma (HNSCC), but currently no drug is available to target it directly. CRISPR-Cas9 has been intensively used to modify cancer-associated genes. Using CRISPR-Cas9 gene editing system could deplete ATAD3A in HNSCC cells, but challenges remain as CRISPR editing components must be transported into cells to exert their function. There is a need to explore effective in vivo delivery systems to accelerate the clinical use of CRISPR-Cas9. Methods: We developed and optimized lipid nanoparticles (LNPs) to deliver Cas9 mRNA along with single guide RNA that targeted ATAD3A in the mouse tongue tumors. Molecular alterations were examined by Western blotting and immunohistochemistry. Cancer cell growth was assessed by MTT, colony formation, soft agar, and 3D cultures. The therapeutic efficacy in tumor development was evaluated in orthotopic tongue tumor NSG mice. Results: We developed CRISPR-based ATAD3A-targeting nanodrugs by loading Cas9 mRNA and anti-ATAD3A sgRNAs into LNPs. Treatment tongue tumors established in NSG mice with LNP-sgATAD3A remarkably repressed tumor growth and downregulated the mitochondrial ERK1/2 oncogenic signaling. As the ATAD3A-ERK1/2 signaling axis drives HNSCC development in a RAS-independent fashion, the addition of LNP-sgATAD3A to the RAS inhibitor salirasib potentiated anticancer activity for HNSCC compared with single arm treatment. Conclusion: Our significant findings demonstrate a novel approach to inhibiting ATAD3A in tumors and provide a possible therapeutic strategy to enhance the success of multimodality therapy in cancer patients. Citation Format: Yong Teng, Fanghui Chen, Liwei Lang, Yamin Li. LNP-CRISPR Gene Editing Enables in Vivo ATAD3A Depletion and Induces the Remission of Head and Neck Cancer [abstract]. In: Proceedings of the 11th Annual Symposium on Global Cancer Research; Closing the Research-to-Implementation Gap; 2023 Apr 4-6. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2023;32(6_Suppl):Abstract nr 59.