title: Two novel ALK mutations mediate acquired resistance to the next-generation ALK inhibitor alectinib.
abstract: OBJECTIVE
  The first-generation ALK tyrosine kinase inhibitor (TKI) crizotinib is a standard therapy for patients with ALK-rearranged non-small cell lung cancer (NSCLC). Several next-generation ALK-TKIs have entered the clinic and have shown promising activity in crizotinib-resistant patients. As patients still relapse even on these next-generation ALK-TKIs, we examined mechanisms of resistance to the next-generation ALK-TKI alectinib and potential strategies to overcome this resistance.
  
  
  METHODS
  We established a cell line model of alectinib resistance, and analyzed a resistant tumor specimen from a patient who had relapsed on alectinib. We developed Ba/F3 models harboring alectinib-resistant ALK mutations and evaluated the potency of other next-generation ALK-TKIs in these models. We tested the antitumor activity of the next-generation ALK-TKI ceritinib in the patient with acquired resistance to alectinib. To elucidate structure-activity relationships of ALK mutations, we performed computational thermodynamic simulation with MP-CAFEE.
  
  
  RESULTS
  We identified a novel V1180L gatekeeper mutation from the cell line model and a second novel I1171T mutation from the patient who developed resistance to alectinib. Both ALK mutations conferred resistance to alectinib as well as to crizotinib, but were sensitive to ceritinib and other next-generation ALK-TKIs. Treatment of the patient with ceritinib led to a marked response. Thermodynamics simulation suggests that both mutations lead to distinct structural alterations that decrease the binding affinity with alectinib.
  
  
  CONCLUSIONS
  We have identified two novel ALK mutations arising after alectinib exposure that are sensitive to other next-generation ALK-TKIs. The ability of ceritinib to overcome alectinib-resistance mutations suggests a potential role for sequential therapy with multiple next-generation ALK-TKIs.
authors.affiliation: Massachusetts General Hospital Cancer Center, Charlestown, Massachusetts. Department of Medicine, Harvard Medical School, Boston, Massachusetts. Cancer Chemotherapy Center, Japanese Foundation for Cancer Research, Tokyo, Japan.
authors.forename: Ryohei
authors.initials: R
authors.lastname: Katayama
authors.affiliation: Massachusetts General Hospital Cancer Center, Charlestown, Massachusetts. Department of Medicine, Harvard Medical School, Boston, Massachusetts.
authors.forename: Luc
authors.initials: L
authors.lastname: Friboulet
authors.affiliation: Cancer Chemotherapy Center, Japanese Foundation for Cancer Research, Tokyo, Japan.
authors.forename: Sumie
authors.initials: S
authors.lastname: Koike
authors.affiliation: Massachusetts General Hospital Cancer Center, Charlestown, Massachusetts. Department of Medicine, Harvard Medical School, Boston, Massachusetts.
authors.forename: Elizabeth L
authors.initials: EL
authors.lastname: Lockerman
authors.affiliation: Massachusetts General Hospital Cancer Center, Charlestown, Massachusetts.
authors.forename: Tahsin M
authors.initials: TM
authors.lastname: Khan
authors.affiliation: Massachusetts General Hospital Cancer Center, Charlestown, Massachusetts. Department of Medicine, Harvard Medical School, Boston, Massachusetts.
authors.forename: Justin F
authors.initials: JF
authors.lastname: Gainor
authors.affiliation: Massachusetts General Hospital Cancer Center, Charlestown, Massachusetts. Department of Pathology, Massachusetts General Hospital, Boston, Massachusetts.
authors.forename: A John
authors.initials: AJ
authors.lastname: Iafrate
authors.affiliation: Pathology Project for Molecular Targets, The Cancer Institute, Japanese Foundation for Cancer Research, Tokyo, Japan.
authors.forename: Kengo
authors.initials: K
authors.lastname: Takeuchi
authors.affiliation: Processor Research Team, RIKEN Advanced Institute of Computational Sciences 6F, Kobe, Hyogo, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Taiji
authors.affiliation: Graduate School of Medicine, Kyoto University, Kyoto, Japan.
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Okuno
authors.affiliation: Cancer Chemotherapy Center, Japanese Foundation for Cancer Research, Tokyo, Japan. naoya.fujita@jfcr.or.jp jengelman@mgh.harvard.edu ashaw1@mgh.harvard.edu.
authors.forename: Naoya
authors.initials: N
authors.lastname: Fujita
authors.affiliation: Massachusetts General Hospital Cancer Center, Charlestown, Massachusetts. Department of Medicine, Harvard Medical School, Boston, Massachusetts. naoya.fujita@jfcr.or.jp jengelman@mgh.harvard.edu ashaw1@mgh.harvard.edu.
authors.forename: Jeffrey A
authors.initials: JA
authors.lastname: Engelman
authors.affiliation: Massachusetts General Hospital Cancer Center, Charlestown, Massachusetts. Department of Medicine, Harvard Medical School, Boston, Massachusetts. naoya.fujita@jfcr.or.jp jengelman@mgh.harvard.edu ashaw1@mgh.harvard.edu.
authors.forename: Alice T
authors.initials: AT
authors.lastname: Shaw
mesh_terms: D000077548:Anaplastic Lymphoma Kinase; D016227:Benzoquinones / Q000494:pharmacology; D002227:Carbazoles / Q000494:pharmacology* / Q000627:therapeutic use; D002289:Carcinoma, Non-Small-Cell Lung / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000235:genetics / Q000378:metabolism; D045744:Cell Line, Tumor; D000077547:Crizotinib; D004252:DNA Mutational Analysis; D004305:Dose-Response Relationship, Drug; D019008:Drug Resistance, Neoplasm / Q000235:genetics*; D018841:HSP90 Heat-Shock Proteins / Q000037:antagonists & inhibitors; D006801:Humans; D020128:Inhibitory Concentration 50; D047029:Lactams, Macrocyclic / Q000494:pharmacology; D008175:Lung Neoplasms / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000235:genetics / Q000378:metabolism; D008958:Models, Molecular; D009154:Mutation; D010880:Piperidines / Q000494:pharmacology* / Q000627:therapeutic use; D011487:Protein Conformation; D047428:Protein Kinase Inhibitors / Q000494:pharmacology* / Q000627:therapeutic use; D011720:Pyrazoles / Q000494:pharmacology / Q000627:therapeutic use; D011725:Pyridines / Q000494:pharmacology / Q000627:therapeutic use; D020794:Receptor Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors* / Q000737:chemistry / Q000235:genetics*; D014057:Tomography, X-Ray Computed
chemical_list: D016227:Benzoquinones; D002227:Carbazoles; D018841:HSP90 Heat-Shock Proteins; D047029:Lactams, Macrocyclic; D010880:Piperidines; D047428:Protein Kinase Inhibitors; D011720:Pyrazoles; D011725:Pyridines; C112765:tanespimycin; D000077547:Crizotinib; C000626173:ALK protein, human; D000077548:Anaplastic Lymphoma Kinase; D020794:Receptor Protein-Tyrosine Kinases; C582670:alectinib