曲妥珠单抗联合放疗对HER2高表达胃癌细胞的协同杀伤作用

目的:研究曲妥珠单抗联合放疗对人类表皮生长因子受体2（HER2）高表达胃癌细胞NCI-N87的协同杀伤作用。方法:应用细胞增殖与毒性检测（CCK-8）法筛选曲妥珠单抗杀伤胃癌细胞的IC20浓度；将NCI-N87分为对照组与加药组，两组依次给予照射剂量不同的X线（0 Gy、2 Gy、4 Gy、6 Gy、8 Gy），应用克隆形成实验分析两者的杀伤作用；凋亡实验分4组:对照、曲妥珠单抗、2 Gy照射、2 Gy照射+曲妥珠单抗，流式细胞仪用于测定凋亡率。结果:IC20为10 μg/ml。与单纯放疗相比，曲妥珠单抗与放疗同时作用可明显降低细胞存活率，差异具有统计学意义（P＜0.05）。凋亡率为对照（3.80±0.26）%、曲妥珠单抗（4.84±0.14）%、2 Gy照射（6.83±0.17）%、联合组（13.60±0.35）%，曲妥珠单抗或照射组均可增加NCI-N87细胞凋亡率，其中凋亡率在联合组中最高（P＜0.05）。结论:曲妥珠单抗和放疗可协同杀伤HER2高表达的胃癌细胞。

Synergism effect of trastuzumab combined with radiotherapy on HER2 overexpressed gastric cancer cell

Objective:To study the synergism effect of trastuzumab combined with radiotherapy on HER2 overexpressed gastric cancer cells.Methods:The inhibitory effect of trastuzumab on NCI-N87 cell proliferation was measured by CCK-8 assay in order to select the IC20 antibody concentration.NCI-N87 cells were divided into the control group and trastuzumab group.They were both treated with different doses of external irradiation (0 Gy,2 Gy,4 Gy,6 Gy,8 Gy).Then the clony formation assay was used to analyze the synergism effect.The experiment was divided into 4 groups:Control,trastuzumab,2 Gy irradiation and the combined group.Cell apoptosis was detected by the flow cytometry.Results:The IC20 of trastuzumab was 10 μg/ml.Compared with radiotherapy alone,trastuzumab combined with radiotherapy can significantly reduce cell viability (P＜0.05).Apoptosis rates were in control (3.80±0.26)%,trastuzumab (4.84±0.14)%,2 Gy irradiation (6.83±0.17)% and the combined group (13.60±0.35)%.The cell apoptosis induction effect of the trastuzumab combined with radiotherapy group was better than the single treatment (P＜0.05).Conclusion:Trastuzumab combined with radiotherapy has the synergism effect on HER2 overexpressed gastric cancer cells.