Targeted CRISPR knockout screening identifies known and novel chemogenomic interactions between DNA damaging agents...

Area of Science:

• Genetics
• Cancer Biology
• Molecular Biology

Background:

• Genetic instability, driven by DNA damage repair (DDR) gene mutations, is central to cancer development.
• While DDR pathways are understood, the full chemogenomic landscape of DNA-damaging agent (DDA) interactions remains largely unmapped.
• The chemical diversity of DDAs and the complexity of DDR networks necessitate comprehensive interaction mapping.

Purpose of the Study:

• To systematically map the chemogenomic interactions between DDR genes and DDAs.
• To identify novel DDR-DDA relationships using a high-throughput screening approach.
• To understand the specific roles of DDR pathways in response to various DNA-damaging agents.

Main Methods:

• Developed and employed a DDR-targeted CRISPR knockout screening strategy.
• Assessed interactions between 353 DNA repair genes and 15 distinct DDAs in LN229 glioma cells.
• Analyzed a dataset comprising 5295 DDR-related chemogenomic interactions.

Main Results:

• Identified numerous established and novel DDR-DDA interactions.
• Revealed a specific role for transcription-coupled nucleotide excision repair in repairing alkylating agent adducts.
• Demonstrated pathway-specific repair dependencies, including the Fanconi anemia pathway for methyl lesions and distinct double-strand break repair following topoisomerase poison treatment.
• Uncovered repair dependencies for imidazotetrazine drugs like temozolomide.

Conclusions:

• The study provides a comprehensive map of DDR-DDA chemogenomic interactions, revealing novel functional relationships.
• Findings highlight specific DDR pathway involvements in repairing diverse DNA lesions induced by various agents.
• Uncovered interactions offer potential targets for developing novel cancer therapies and improving existing treatments.