title: Crizotinib-resistant NPM-ALK mutants confer differential sensitivity to unrelated Alk inhibitors.
abstract: The dual ALK/MET inhibitor crizotinib was recently approved for the treatment of metastatic and late-stage ALK+ NSCLC, and is currently in clinical trial for other ALK-related diseases. As predicted after other tyrosine kinase inhibitors' clinical experience, the first mutations that confer resistance to crizotinib have been described in patients with non-small cell lung cancer (NSCLC) and in one patient inflammatory myofibroblastic tumor (IMT). Here, we focused our attention on the anaplastic large cell lymphoma (ALCL), where the oncogenic fusion protein NPM-ALK, responsible for 70% to 80% of cases, represents an ideal crizotinib target. We selected and characterized 2 human NPM-ALK+ ALCL cell lines, KARPAS-299 and SUP-M2, able to survive and proliferate at different crizotinib concentrations. Sequencing of ALK kinase domain revealed that a single mutation became predominant at high crizotinib doses in each cell line, namely L1196Q and I1171N in Karpas-299 and SUP-M2 cells, respectively. These mutations also conferred resistance to crizotinib in Ba/F3 cells expressing human NPM-ALK. The resistant cell populations, as well as mutated Ba/F3 cells, were characterized for sensitivity to two additional ALK inhibitors: the dual ALK/EGFR inhibitor AP26113 and NVP-TAE684. While L1196Q-positive cell lines were sensitive to both inhibitors, cells carrying I1171N substitution showed cross-resistance to all ALK inhibitors tested. This study provides potentially relevant information for the management of patients with ALCL that may relapse after crizotinib treatment.
authors.affiliation: Department of Health Sciences, University of Milano-Bicocca, Via Cadore 48, Monza 20900, Italy. mceccon.manuscript@gmail.com
authors.forename: Monica
authors.initials: M
authors.lastname: Ceccon
authors.forename: Luca
authors.initials: L
authors.lastname: Mologni
authors.forename: William
authors.initials: W
authors.lastname: Bisson
authors.forename: Leonardo
authors.initials: L
authors.lastname: Scapozza
authors.forename: Carlo
authors.initials: C
authors.lastname: Gambacorti-Passerini
mesh_terms: D000077548:Anaplastic Lymphoma Kinase; D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D048708:Cell Growth Processes / Q000187:drug effects; D045744:Cell Line, Tumor; D000077547:Crizotinib; D019008:Drug Resistance, Neoplasm; D006801:Humans; D017728:Lymphoma, Large-Cell, Anaplastic / Q000188:drug therapy / Q000201:enzymology / Q000473:pathology; D051379:Mice; D008958:Models, Molecular; D047428:Protein Kinase Inhibitors / Q000494:pharmacology*; D011505:Protein-Tyrosine Kinases / Q000235:genetics* / Q000378:metabolism; D011720:Pyrazoles / Q000494:pharmacology*; D011725:Pyridines / Q000494:pharmacology*; D020794:Receptor Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors*; D014162:Transfection
chemical_list: D047428:Protein Kinase Inhibitors; D011720:Pyrazoles; D011725:Pyridines; D000077547:Crizotinib; C107023:p80(NPM-ALK) protein; C000626173:ALK protein, human; C000626174:Alk protein, mouse; D000077548:Anaplastic Lymphoma Kinase; D011505:Protein-Tyrosine Kinases; D020794:Receptor Protein-Tyrosine Kinases