1.Analyzing the Sensitivity of EGFR-L861Q Mutation to TKIs and A Case Report
WANG XINGXING ; DONG YUTONG ; LIANG TINGTING ; ZHANG XIONGJI ; MA KEWEI ; CUI YONGSHENG
Chinese Journal of Lung Cancer 2015;(9):592-598
Background and objective hTe signiifcant effcacy of tyrosine kinase inhibitors (TKIs) has been ap-proved 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. hTis study aims to discuss the best treatment for advanced NSCLC patients with EG-FR-L861Q mutation by analyzing the differences among the structures of wild-type EGFR, activating mutant EGFR-L858R, and EGFR-L861Q mutation. Method The protein structures of wild-type EGFR were reconstructed. EGFR-L858R and EGFR-L861Q mutation were activated. hTe differences among the three kinds of protein conformation were analyzed using homologous modeling technique. Results hTe structure of EGFR-L858R and wild-type EGFR exhibited notable distinctions. hTe 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 ifrst-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. Conclusion hTe analysis of the protein conformation of EGFR-L861Q muta-tion 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 atfer ifrst-line chemotherapy.