Abstract The success of precision oncology depends on our ability to translate accumulating genomic data into actionable treatment options in a personalized manner. The first step requires the identification of a specific genomic signature, then matching this signature with the most effective therapy. Unfortunately, more often than not, we do not have a specific cancer drug that is effective for the mutation found in a specific tumor. We desperately need to identify new targets so that we can develop new drugs to deliver on the promise of precision cancer medicine. In addition, we need to develop a rational way to combine drugs that does not depend on trial and error. To systematically interrogate such genetic interactions, we designed a dual CRISPR-Cas9 perturbation library targeting the top 1000 genes upregulated in KRAS mutant cancers (lung, pancreas and colon cancers). We performed these combinatorial double knockout screens on 100K gene pairs and identified 27 pairs whose co-disruption results in a loss of cellular fitness. We also applied this system to map buffering interactions, and 16 pairs of genes were identified. We validated those top pairs of genes by performing mini-screens using CRISPR-Cas12a on more KRAS mutant and KRAS WT cell lines. Overall, our findings will provide insight into potential combinational targets in KRAS mutant tumors and will highlight the synergistic effects that occurs among the novel targets, and other proliferation, metastasis, immune and metabolism modules. Citation Format: Rand Arafeh, Xiang Zhang, Laura Chang, Arshia Hassan, Lydia Sawyer, Helen Wang, Joey Li, James McFarland, Joshua Dempster, Peter DeWeirdt, John Doench, Chad Myers, William C. Hahn. Mapping the genetic landscape of KRAS mutant cancer cells using combinatorial CRISPR screens abstract. In: Proceedings of the AACR Special Conference in Cancer Research: RAS Oncogenesis and Therapeutics; 2026 Mar 5-8; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Res 2026;86 (5Suppl₁): Abstract nr A014.
Arafeh et al. (2026) studied this question.