Uncovering Oncogenic Kras Allele Specific Phenotypes Using An Isogenic Mef Cell Line System

The RAS Initiative at the Frederick National Laboratory has generated an isogenic mouse embryonic fibroblast (MEFs) cell line panel containing single transgene alleles using the RAS-less MEF system developed by Matthias Drosten and Mariano Barbacid (CNIO). These MEFs are H, N and K-RAS null, growth is dependent on exogenous RAS or MAPK pathway activation. The panel includes: KRAS 4A WT, KRAS 4B WT, KRAS 4B G12C, G12D, G12V, G13D, Q61L, Q61R, HRAS WT, NRAS WT or BRAF V600E. The workflow to generate the lines requires cre-lox removal of endogenous KRAS and the cells arrest in the G1 phase of the cycle. Proliferation is resumed through the delivery of the transgene to the cells using lentiviral transduction. Clonal cell lines are derived from the initial pools and are thoroughly characterized including confirmation of endogenous KRAS gene removal, identification of the transgene insertion site(s), calculation of proliferation rates and doubling times, analysis of signaling pathways, response to tool compounds and exome sequenced to exclude lines with mutations in onco-relevant genes. This panel is a unique resource that can be used to ask allele and isoform specific questions (gene expression profiles, GTP-loading, etc.) and screen for RAS inhibitors as well as determine novel compound specificity. This panel is available to the academic RAS research community. Citation Format: Nicole Fer, Brian Smith, Leslie Garvey, William Burgan, Katie Powell, Kanika Sharma, Andrew Waters, Xiaolin Wu, Dan Soppet, Robert Stephens, Dwight Nissley, Matthew Holderfield, Rachel K. Bagni. Uncovering oncogenic KRAS allele specific phenotypes using an isogenic MEF cell line system. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 1131.