Research Of Gefitinib In Combination With Paclitaxel And Cisplatin To Inhibit Cell Proliferation And Induct Apoptosis On Lung Adenocarcinoma Cell Lines

Objective: The study researched the proliferation inhibition and apoptotic-inducing effectsof single or combined or different sequences application of gefitinib and chemotherapy(paclitaxel plus cisplatin) on human lung adenocarcinoma cell lines A549with EGFRwide-type and HCC827with EGFR mutant-type in vitro, to explore the best regimen ofgefitinib and chemotherapy on human lung adenocarcinoma cell lines with different EGFRgene types, thereby, contribute to the experimental and theoretical basis of EGFR-TKI inclinic application.Methods: Culture human lung adenocarcinoma cell lines A549with EGFR wide-type andHCC827with EGFR mutant-type in vitro. Identified the proliferation inhibition andapoptotic-inducing effects of single or combined application or different sequencesapplication of gefitinib and chemotherapy (paclitaxel plus cisplatin) on the two cell lines,specific methods include:1.Identified the inhibition rate of gefitinib (A549：16、8、4、2、1umol/L；HCC827：0.16、0.08、0.04、0.02、0.01umol/L) or chemotherapy (paclitaxel10、1、0.1、0.01、0.001umol/L+cisplatin0.5ug/mL) single application at24,48,72hours viaMTT test, then draw the LogD-E and calculate IC50.2.Identified the inhibition rate ofcombined or different sequences application of gefitinib and chemotherapy at72hours viaMTT test.3. Identified the cell apoptosis rate of A549cells and HCC827cells by FCM-Annexin V-FITC/PI double staining with72hours. Results:1.The single application of gefitinib and chemotherapy(Paclitaxel+cisplatin) caninhibit the growth of A549and HCC827cells, which is in a concentration and timedependent manner; When gefitinib act on A549cells(EGFR wide-type) after72hours, IC50is7.877umol/L,which is0.043umol/L on HCC827cells(EGFR mutant-type) at the same time,the IC50of A549is183times of HCC827.2.To A549cells with EGFR wide-type, whenchemotherapy(Paclitaxel+cisplatin) first and sequential gefitinib later, the highest inhibitionrate is90.77%, the apoptosis rate is49.98%, compared with other groups and use singleapplication were significantly improved(P＜0.05);when gefitinib combined withchemotherapy(Paclitaxel plus cisplatin) at the same time, the highest inhibition rate is70.55%, similar to chemotherapy single application(70.23%), the differences were nosignificant, the apoptosis rate is26.23%, which is lower than chemotherapy singleapplication(27.83%),(P＜0.05);when gefitinib first and sequential chemotherapy (Paclitaxelplus cisplatin) later, the highest inhibition rate is58.79%, the apoptosis rate is12.36%,theywere all lower than chemotherapy single application(P＜0.05).3. To HCC827cells withEGFR mutant-type, when gefitinib combined with chemotherapy (Paclitaxel plus cisplatin)at the same time, the highest inhibition rate is89.70%, the apoptosis rate is54.66%,compared with other groups and use single application were significantly improved(P＜0.05);when chemotherapy(Paclitaxel plus cisplatin) first and sequential gefitinib later,, thehighest inhibition rate is83.11%, the apoptosis rate is50.96%, compared with gefitinib firstand sequential chemotherapy(Paclitaxel plus cisplatin) later groups or single application atthe same concentration were significantly improved(P＜0.05); when gefitinib first andsequential chemotherapy(Paclitaxel plus cisplatin) later, the highest inhibition rate is65.39%,the apoptosis rate is24.77%,they were all lower than single application at the sameconcentration (P＜0.05).Conclusion:1. Gefitinib can inhibit HCC827cells growth with small concentration, and italso can inhibit A549cells growth when a higher concentration, the sensitivity of the formerto gefitinib is approximately183times of the latter.2. To A549cells with EGFR wide-type,Using chemotherapy (Paclitaxel plus cisplatin) first and sequential gefitinib later had thehighest inhibition rate and apoptosis rate; using gefitinib combined chemotherapy(Paclitaxel plus cisplatin) at the same time had no advantage compared with single application; usinggefitinib first and sequential chemotherapy(Paclitaxel plus cisplatin) later had the lowerinhibition rate and apoptosis rate than single application.3. To HCC827cells with EGFRmutant-type, using gefitinib combined with chemotherapy (Paclitaxel plus cisplatin) at thesame time or using chemotherapy(Paclitaxel plus cisplatin) first and sequential gefitinib later,the inhibition rate and the apoptosis rate were all added, but using gefitinib combined withchemotherapy (Paclitaxel plus cisplatin) at the same time had the highest inhibition rate andapoptosis rate, the difference had significant; using gefitinib first and sequentialchemotherapy(Paclitaxel plus cisplatin) later had the lower inhibition rate and apoptosis ratethan single application.