Abstract 1170: NCI-H1975 L858R/T790M/C797S isogenic cell line for next-generation EGFR inhibitor screening

Abstract

Abstract Non-small-cell lung cancer (NSCLC) is the most common cause of cancer death. Over-activation of EGFR occurs in 13%~23% of NSCLC. The identification of EGFR as a cancer driver gene had led to rapid development of NSCLC targeted therapy, but the mutation of EGFR during treatment can cause drug resistance and cancer relapse. For example, T790M mutation causes resistance to the first generation of EGFR inhibitor Erlotinib and C797S mutation contributes to the resistance to the 3rd EGFR inhibitor AZD9291. There are several human cell lines for T790M mutation research, but there is not yet any primary human cancer cell line with C797S mutation. In the current study, a human isogenic EGFR C797S mutation cell line was generated through introducing nucleotide mutation into the EGFR gene in NCI-H1975 cell line using CRISRP technology, which originally bears L858R and T790M mutations of EGFR. First, the sgRNA sequence around the exon-20 of EGFR gene was screened using CRIPSR plasmid. Second, the donor plasmid with the homology arm containing exon-20 of EGFR and selecting marker was constructed and co-transfected into the parental cell line. Then, the NCI-H1975 C797S isogenic cell line was obtained and confirmed after screening over 100 single clones using the PCR method. The NCI-H1975 C797S isogenic cell line was resistant to AZD9291 but sensitive with EAI045 (the potential 4th generation EGFR inhibitor) combined with cetuximab. These data indicate that our NCI-H1975 L858R/T790M/C797S isogenic line is a useful model for next generation EGFR inhibitor study. Citation Format: Feng Hao, Feng He, Wenna Zhang, Zhaoshuai Bai, Jinying Ning. NCI-H1975 L858R/T790M/C797S isogenic cell line for next-generation EGFR inhibitor screening [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1170.