表皮生长因子受体单克隆抗体对辐射诱导肺腺癌细胞SPC-A-1的增敏作用

Radiosensitization of epithelial growth factor receptor monoclonal antibody on lung adenocarcinoma cell line SPC-A-1

目的:探讨表皮生长因子受体单克隆抗体(C225)作为靶向治疗药物联合放射治疗对肺腺癌细胞系(SPC-A-1)的增敏作用,为临床综合治疗非小细胞肺癌提供理论依据。方法:SPC-A-1细胞体外传代培养6代以上,取对数生长期细胞进行实验。SPC-A-1细胞分为对照组(PBS)、照射组(4 Gy)、C225组(100 nmol.L-1)和照射+C225组(4Gy+100 nmol.L-1),Hoechst 33258染色后采用荧光显微镜观察细胞凋亡情况。SPC-A-1细胞分别给予0、2、4和8 Gy 6-MV X射线照射后继续培养72 h,收集细胞,分为照射组和实验组(照射+C225组),用流式细胞仪检测细胞凋亡率。SPC-A-1细胞分为对照组(PBS)、C225组(100 nmol.L-1)、照射组(8 Gy)和照射+C225组(8 Gy+100 nmol.L-1),作用48 h后,采用流式细胞仪检测细胞周期。结果:Hoechst33258染色后,照射+C225组凋亡细胞数明显高于照射组和C225组;细胞凋亡实验,实验组细胞凋亡率明显高于相应剂量照射组(P<0.05)。细胞周期检测,与对照组比较,C225组G0+G1期细胞增加(P<0.05),照射组G2+M期细胞增加(P<0.05),而照射+C225组G0+G1和G2+M期细胞均增加(P<0.05);与对照组比较,C225组、照射组及照射+C225组S期细胞均下降(P<0.05)。结论:C225对SPC-A-1细胞系有放射增敏作用,其机制可能与诱导细胞凋亡和细胞周期G0+G1期阻滞有关。

Objective To explore the radiosensitivity of C225（cetuximab）,an anti-epithelial growth factor receptor monoclonal antibody,which combined with irradiation against lung adenocarcinoma cell line SPC-A-1,and provide theoretical basis for clinical combined treatment in non-small lung cancer.Methods SPC-A-1 were cultivated in vitro for 6 passages,and the SPC-A-1 in logarithmic growth phase were seleted for experiment.The SPC-A-1 were divided into control group（PBS）,irradiation group（4 Gy）,C225 group（100 nmol·L-1） and irradiation＋C225 group（4 Gy＋100 nmol·L-1）.The apoptosis of SPC-A-1 was observed by fluorescence microscope after Hoechst 33258 staining.SPC-A-1 were treated with different doses of 6-MV X-Rays including 0,2,4 and 8 Gy alone or together with C225（100 nmol·L-1）,72 h after irradiation,the cells were divided into irradiation group and experimental group（irradiation＋C22）,the apototic rate was detected by flow cytometry（FCM）.SPC-A-1 were divided into control group（PBS）,C225 group（100 nmol·L-1）,irradiation group（8 Gy） and irradiation＋C225 group（8 Gy＋100 nmol·L-1）,48 h after irradiation,the cell cycle was determined by FCM.Results After staining by Hoechst 33258,the number of apoptotic cells in irradiation＋C225 group was significantly higher than those in irradiation group and C225 group.In apoptosis experiment,the apoptotic rate in experimental group was higher than that in irradiation group（P0.05）.The cell cycle analysis showed that compared with control group,the number of cells in G0＋G1 phase was increased in C225 group（P0.05）,the number of cells in G0＋G1 and G2＋M phrases in irradiation＋C225 group was increased（P0.05）,the number of cells in S phrase of three groups was decreased（P0.05）.Conclusion The mechanism of radiosensitivity enhancement of C225 to SPC-A-1 may be related to arresting G0＋G1 phases and inducing apoptosis.