Basic Research Of Drug Sensitivity Test In Vitro Of Icotinib Guiding Clinical Medication In Lung Cancer

Objective: To explore the relationship between EGFR gene mutation status and the inhibitory effects of icotinib in lung cancer cells,and provide some reference for clinical drug sensitivity test in vitro as one of the methods to predict the efficacy of EGFR-TKIs.Methods: A549 and HCC827 lung cancer cell lines were cμltured in vitro,and identified by morphological observation and immunocytochemical staining.EGFR gene mutation status was detected by xTAG liquidchip technology.Preliferation and apoptosis of icotinib on two cell lines in vitro were measured respectively through CCK-8 assay and Annexin V-FITC/PI double staining.All experimental data were statistically analyzed with SPSS(21.0 software).P value less than 0.05 was considered statically significant.Results: 1)The characteristics of morphological and immunocytochemical staining of two cell lines were consistent with those of A549 and HCC827 lung cancer cell lines.2)The EGFR gene of A549 cell line was wild type,while that of HCC827 cell line was exon 19 deletion mutant(p.E746_A750del).3)The median inhibitory concentrations(IC50)of icotinib on A549 and HCC827 cell lines for 48 hours were 9.65±0.78μmol/L and 0.12±0.01μmol/L,respectively.The difference between the two was statistically significant(P=0.000).4)After incubation with 0.1μmol/L icotinib for 48 h,the cell inhibition rate(CIR)was 0 and(45.31±1.33)% respectively(P=0.000).And the cell apoptosis rate(CAR)was(1.81±0.47)% and(62.25±2.45)% respectively(P=0.000).After incubation with 1μmol/L icotinib for 48 h,the CIR was(18.95±0.78)% and(75.53±2.98)% respectively(P=0.000),and CAR was(39.91±2.04)% and(89.26±3.81)% respectively(P=0.000).Conclusions: In this study,the feasibility of immunocytochemical staining for identification of A549 and HCC827 lung cancer cell lines was confirmed preliminarily,and the resμlt of immunocytochemical staining can be used as reference for other studies.More importantly,icotinib showed sronger inhibitory effect on the proliferation of EGFR mutant HCC827 cells than wild-type A549 cells,suggesting that our research methods are practical and reliable,and can be used as reference for the clinical application of drug sensitivity test in vitro on EGFR-TKIs.