title: NSCLC harboring EGFR exon-20 insertions after the regulatory C-helix of kinase domain responds poorly to known EGFR inhibitors.
abstract: Anecdote clinical observations hint that non-small cell lung cancer (NSCLC) with exon-20 insertions might respond poorly to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs), contrasting to those with classic mutations. Lack of patient-derived experimental models has been a major hurdle for the discovery of new treatment for the diseases. We established two NSCLC-PDXs harboring two different exon-20 insertions, LU0387-adenocarcinoma (ADC) with a nine-base insertion at 2319 (H773-V774insNPH) and LU3075-squamous cell carcinoma (SCC) with a nine-base insertion at 2316 (P772-H773insDNP). Both insertions immediately follow the regulatory C-helix of the kinase domain. Contrary to the generally good responses to EGFR inhibitors observed in PDXs with classic mutations, both exon-20 insertions are largely resistant to cetuximab and TKIs in vivo, suggesting fundamental difference from the classic EGFR mutations, consistent with the poor response rate to TKI seen in anecdotal clinic reports. It is worth noting that although responses are generally poor, they differ between the two exon-20 mutants depending on the type of TKI. In vitro drug sensitivity assays using established primary cell lines from our two PDXs largely confirmed the in vivo data. Our data from patient-derived experimental models confirmed that exon-20 insertions in domain immediately following the C-helix confer poor response to all known EGFR inhibitors, and suggested that these models can be utilized to facilitate the discovery of new therapies targeting NSCLC harboring exon-20 insertions.
authors.affiliation: Crown Bioscience, Inc, 3375 Scott Blvd, Suite 108, Santa Clara, CA.
authors.forename: Mengmeng
authors.initials: M
authors.lastname: Yang
authors.affiliation: Crown Bioscience, Inc, 3375 Scott Blvd, Suite 108, Santa Clara, CA.
authors.forename: Xiaoxi
authors.initials: X
authors.lastname: Xu
authors.affiliation: Crown Bioscience, Inc, 3375 Scott Blvd, Suite 108, Santa Clara, CA.
authors.forename: Jie
authors.initials: J
authors.lastname: Cai
authors.affiliation: Crown Bioscience, Inc, 3375 Scott Blvd, Suite 108, Santa Clara, CA.
authors.forename: Jinying
authors.initials: J
authors.lastname: Ning
authors.affiliation: Crown Bioscience, Inc, 3375 Scott Blvd, Suite 108, Santa Clara, CA.
authors.forename: Jean Pierre
authors.initials: JP
authors.lastname: Wery
authors.affiliation: Crown Bioscience, Inc, 3375 Scott Blvd, Suite 108, Santa Clara, CA.|State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing, China.
authors.forename: Qi-Xiang
authors.initials: QX
authors.lastname: Li
mesh_terms: D000230:Adenocarcinoma / Q000188:drug therapy* / Q000235:genetics / Q000473:pathology; D002289:Carcinoma, Non-Small-Cell Lung / Q000188:drug therapy / Q000235:genetics* / Q000473:pathology; D002294:Carcinoma, Squamous Cell / Q000188:drug therapy* / Q000235:genetics / Q000473:pathology; D045744:Cell Line, Tumor; D019008:Drug Resistance, Neoplasm / Q000235:genetics; D066246:ErbB Receptors / Q000037:antagonists & inhibitors / Q000235:genetics*; D005091:Exons / Q000235:genetics; D006801:Humans; D009154:Mutation; D047428:Protein Kinase Inhibitors; D011799:Quinazolines / Q000008:administration & dosage; D023041:Xenograft Model Antitumor Assays
chemical_list: D047428:Protein Kinase Inhibitors; D011799:Quinazolines; C512478:EGFR protein, human; D066246:ErbB Receptors
keywords: EGFR-exon-20 insertion; Erbitux; PDX; TKI