title: Elucidation of Resistance Mechanisms to Second-Generation ALK Inhibitors Alectinib and Ceritinib in Non-Small Cell Lung Cancer Cells.
abstract: Crizotinib is the first anaplastic lymphoma kinase (ALK) inhibitor to have been approved for the treatment of non-small cell lung cancer (NSCLC) harboring an ALK fusion gene, but it has been found that, in the clinic, patients develop resistance to it. Alectinib and ceritinib are second-generation ALK inhibitors which show remarkable clinical responses in both crizotinib-naive and crizotinib-resistant NSCLC patients harboring an ALK fusion gene. Despite their impressive activity, clinical resistance to alectinib and ceritinib has also emerged. In the current study, we elucidated the resistance mechanisms to these second-generation ALK inhibitors in the H3122 NSCLC cell line harboring the EML4-ALK variant 1 fusion in vitro. Prolonged treatment of the parental H3122 cells with alectinib and ceritinib led to two cell lines which are 10 times less sensitive to alectinib and ceritinib than the parental H3122 cell line. Although mutations of ALK in its kinase domain are a common resistance mechanism for crizotinib, we did not detect any ALK mutation in these resistant cell lines. Rather, overexpression of phospho-ALK and alternative receptor tyrosine kinases such as phospho-EGFR, phospho-HER3, and phospho-IGFR-1R was observed in both resistant cell lines. Additionally, NRG1, a ligand for HER3, is upregulated and responsible for resistance by activating the EGFR family pathways through the NRG1-HER3-EGFR axis. Combination treatment with EGFR inhibitors, in particular afatinib, was shown to be effective at overcoming resistance. Our study provides new mechanistic insights into adaptive resistance to second-generation ALK inhibitors and suggests a potential clinical strategy to combat resistance to these second-generation ALK inhibitors in NSCLC.
authors.affiliation: Department of Medical Oncology, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi, 710061, P.R. China; University of Michigan Comprehensive Cancer Center, University of Michigan, Ann Arbor, MI, 48109, USA; Department of Internal Medicine, University of Michigan, Ann Arbor, MI, 48109, USA.
authors.forename: Xuyuan
authors.initials: X
authors.lastname: Dong
authors.affiliation: University of Michigan Comprehensive Cancer Center, University of Michigan, Ann Arbor, MI, 48109, USA; Department of Pathology, University of Michigan, Ann Arbor, MI, 48109, USA; Michigan Center for Translational Pathology, University of Michigan, Ann Arbor, MI, 48109, USA.
authors.forename: Ester
authors.initials: E
authors.lastname: Fernandez-Salas
authors.affiliation: Department of Medical Oncology, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi, 710061, P.R. China. Electronic address: doclienxiao@sina.com.
authors.forename: Enxiao
authors.initials: E
authors.lastname: Li
authors.affiliation: University of Michigan Comprehensive Cancer Center, University of Michigan, Ann Arbor, MI, 48109, USA; Department of Internal Medicine, University of Michigan, Ann Arbor, MI, 48109, USA; Michigan Center for Translational Pathology, University of Michigan, Ann Arbor, MI, 48109, USA; Department of Pharmacology, University of Michigan, Ann Arbor, MI, 48109, USA; Department of Medicinal Chemistry, University of Michigan, Ann Arbor, MI, 48109, USA. Electronic address: shaomeng@umich.edu.
authors.forename: Shaomeng
authors.initials: S
authors.lastname: Wang
mesh_terms: D000077548:Anaplastic Lymphoma Kinase; D002227:Carbazoles / Q000008:administration & dosage; D002289:Carcinoma, Non-Small-Cell Lung / Q000188:drug therapy* / Q000235:genetics / Q000473:pathology; D045744:Cell Line, Tumor; D019008:Drug Resistance, Neoplasm / Q000187:drug effects / Q000235:genetics*; D066246:ErbB Receptors / Q000037:antagonists & inhibitors / Q000096:biosynthesis*; D015972:Gene Expression Regulation, Neoplastic; D051097:Glial Cell Line-Derived Neurotrophic Factor Receptors / Q000096:biosynthesis; D006801:Humans; D009154:Mutation; D020890:Neuregulin-1 / Q000096:biosynthesis* / Q000235:genetics; D015514:Oncogene Proteins, Fusion / Q000235:genetics; D010880:Piperidines / Q000008:administration & dosage; D011743:Pyrimidines / Q000008:administration & dosage; D020794:Receptor Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors / Q000235:genetics*; D020893:Receptor, ErbB-3 / Q000096:biosynthesis; D015398:Signal Transduction / Q000187:drug effects; D013450:Sulfones / Q000008:administration & dosage
chemical_list: D002227:Carbazoles; C522504:EML4-ALK fusion protein, human; C494987:GFRA1 protein, human; D051097:Glial Cell Line-Derived Neurotrophic Factor Receptors; C094131:NRG1 protein, human; D020890:Neuregulin-1; D015514:Oncogene Proteins, Fusion; D010880:Piperidines; D011743:Pyrimidines; D013450:Sulfones; C000626173:ALK protein, human; D000077548:Anaplastic Lymphoma Kinase; C512478:EGFR protein, human; C581292:ERBB3 protein, human; D066246:ErbB Receptors; D020794:Receptor Protein-Tyrosine Kinases; D020893:Receptor, ErbB-3; C586847:ceritinib; C582670:alectinib