title: [Analyzing the Sensitivity of EGFR-L861Q Mutation to TKIs and A Case Report].
abstract: OBJECTIVE
  The significant efficacy of tyrosine kinase inhibitors (TKIs) has been approved for advanced non-small cell lung cancer (NSCLC) patients with activating epidermal growth factor receptor (EGFR) mutations. No clear evidence exists that EGFR-L861Q is sensitive to TKIs, and the best treatment for NSCLC patients with EGFR-L861Q mutation is undetermined. This study aims to discuss the best treatment for advanced NSCLC patients with EGFR-L861Q mutation by analyzing the differences among the structures of wild-type EGFR, activating mutant EGFR-L858R, and EGFR-L861Q mutation.
  
  
  METHODS
  The protein structures of wild-type EGFR were reconstructed. EGFR-L858R and EGFR-L861Q mutation were activated. The differences among the three kinds of protein conformation were analyzed using homologous modeling technique.
  
  
  RESULTS
  The structure of EGFR-L858R and wild-type EGFR exhibited notable distinctions. The structure of EGFR-L861Q mutation was different compared with wild-type EGFR and activating mutant EGFR-L858R protein conformations. NSCLC patients with EGFR-L861Q mutation were given chemotherapy as the first-line of therapy, and TKIs were applied to maintain treatment when the tumor is unchanged. Effect evaluation result was improved when the lung computed tomography lesions were reviewed.
  
  
  CONCLUSIONS
  The analysis of the protein conformation of EGFR-L861Q mutation and the curative effect of chemotherapy with TKIs could help predict the sensitivity of EGFR-L861Q to TKIs. Combining the analysis with a clinical case, maintenance treatment with TKIs may achieve satisfactory curative effect in advanced NSCLC patients who have achieved disease control after first-line chemotherapy.
authors.affiliation: Department of Medicine, Zhoushan Hospital, Zhoushan 316000, China;Department of Cancer Center, The First Hospital of Jilin University, Changchun 132000, China.
authors.forename: Xingxing
authors.initials: X
authors.lastname: Wang
authors.affiliation: Clinical Medical College of Yanbian University, Yanbian 133000, China.
authors.forename: Yutong
authors.initials: Y
authors.lastname: Dong
authors.affiliation: Department of Cancer Center, The First Hospital of Jilin University, Changchun 132000, China.
authors.forename: Tingting
authors.initials: T
authors.lastname: Liang
authors.affiliation: Department of Thoracic Surgery, The First Hospital of Jilin University, Changchun 132000, China.
authors.forename: Xiongji
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Department of Cancer Center, The First Hospital of Jilin University, Changchun 132000, China.
authors.forename: Kewei
authors.initials: K
authors.lastname: Ma
authors.affiliation: Department of Thoracic Surgery, The First Hospital of Jilin University, Changchun 132000, China.
authors.forename: Yongsheng
authors.initials: Y
authors.lastname: Cui
mesh_terms: D002289:Carcinoma, Non-Small-Cell Lung / Q000188:drug therapy* / Q000201:enzymology / Q000235:genetics* / Q000473:pathology; D066246:ErbB Receptors / Q000037:antagonists & inhibitors* / Q000737:chemistry / Q000235:genetics*; D006801:Humans; D008175:Lung Neoplasms / Q000188:drug therapy* / Q000453:epidemiology / Q000235:genetics* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D008958:Models, Molecular; D011487:Protein Conformation; D047428:Protein Kinase Inhibitors / Q000494:pharmacology* / Q000627:therapeutic use
chemical_list: D047428:Protein Kinase Inhibitors; C512478:EGFR protein, human; D066246:ErbB Receptors