鞘氨醇激酶1抑制剂和5-FU联合应用对体外胃癌细胞增殖与凋亡的影响

Effects of sphingosine kinase 1 inhibitors combined with 5-FU on proliferation and apoptosis of gastric cancer cells in vitro

目的观察鞘氨醇激酶1(SphK1)抑制剂二甲基鞘氨醇(DMS)与化疗药物5-氟尿嘧啶(5-FU)联合应用对体外胃癌细胞SGC7901增殖与凋亡的影响。方法体外培养人胃癌细胞株SGC7901,分别单用不同浓度5-FU(1、5、25μg/ml)或5-FU与DMS(1μmol/L)联合应用。MTT比色法检测各组细胞生长抑制率,光镜下观察细胞形态变化,流式细胞术检测各组细胞凋亡率。通过SAS软件进行反应曲面分析,分析两药之间的关系。结果不同浓度的5-FU单用组及联用DMS组的抑制率差异有统计学意义(P<0.05),联用组抑制率均高于单用组,两者具有协同作用。单用DMS组及5-FU组的胃癌细胞凋亡率较空白对照组明显增高,联用组凋亡率较单用组明显增加(P<0.05)。结论 DMS可抑制SGC7901细胞的增殖;DMS和5-FU联用显示了较好的协同作用,提示抑制SphK1活性能够提高胃癌细胞对于化疗药物的敏感性。

Objective To investigate the effects of N,N-Dimethylsphingosine（DMS） combined with 5-fluorouracil（5-FU） on the proliferation and apoptosis of gastric cancer cells（SGC7901） in vitro.Methods The SGC7901 cells were incubated in vitro with different concentrations of 5-FU（1,5 μg/ml and 25 μg/ml） alone or combined use of different concentrations of 5-FU and DMS（1 μmol/L）.The growth and survival of SGC7901 cells were determined by MTT assay.Apoptosis was measured using flow cytometry.By the response surface analysis of those inhibition rates,the interactive relationships between the combined drugs were evaluated on the basis of positive/negative value of the cross product coefficient in the response surface equation.Results The inhibition rate of SGC7901 cells by DMS（1 μmol/L） for 24 hours was（10.23±0.74）%.The inhibition rates of SGC7901 cells by 5-FU 1,5 μg/ml and 25 μg/ml were（9.95±3.24）%,（21.4±2.19）% and（45.49±3.60）%,respectively,which were lower than（16.76±0.41）%,（27.28±0.29）% and（52.56±0.36）% when DMS was combined with different concentrations of 5-FU（P〈0.05）.The apoptosis rates of SGC7901 cells were（7.56±1.47）% and（9.08±2.04）% when treated with DMS 1 μmol/L and 5-FU 1 μg/ml,respectively,which were more than（1.48±0.39）% in control group.When 5-FU was combined with DMS,the apoptosis rate was（17.68±3.66）%,which was more than that of each of single 5-FU groups（P〈0.05）.Conclusion DMS is able to suppress SGC7901 cells in vitro and the synergetic effect became evident when it is used in combination with 5-FU,suggesting that sphingosine kinase 1（SphK1） inhibitors could be used as the synergetic agents in chemotherapy.