To Study The Effect Of Sphingosine Kinase-1 Inhibitor N, N-dimethylsphingosine On The Proliferation And Apoptosis In Human Gastric Adenocarcinoma Cell SGC7901 In Vitro

Objective: To investigate the effect of Sphingosine kinase-1(SPHK1) inhibitor N,N-dimethylsphingosine(DMS) on the proliferation and apoptosis in Human gastric adenocarcinoma cell SGC7901 in vitro.Methods: Human gastric adenocarcinoma cell line SGC7901 was cultured in vitro, then added different dose DMS to SGC7901. Expression of SPHK1 gene mRNA was detected by RT-PCR. The effects of DMS on the growth and survival of SGC7901 cells were detected by MTT assay and growth curve assay. Apoptosis was detected using flow cytometry.Results: DMS could effect expression of SPHK1 gene mRNA in SGC7901. There was difference in the mRNA level of SPHK1 gene in SGC7901 cell after the action of the varies concentrations of DMS(0,1,5,25)μmol/L for up to 24 hours. The level of SPHK1 mRNA was reduced with the concentration was increased. The gray rate of SPHK1 with GAPDH was 0.89±0.03,0.73±0.02,0.66±0.03,0.44±0.03.There was significantly difference between every groups (P <0.05). DMS could inhibit the growth of SGC7901 cell significantly. The cells were treated with varies concentrations of DMS(1,5,25)μmol/L for up to 24 hours, 48 hours and 72 hours. The inhibitory rates of the cells were 12.33±2.86%,30.07±2.16%,56.25±1.50% in 24 hours; 37.43±1.97%,53.32±2.64%,72.98±1.52% in 48 hours and 47.10±2.52%,68.87±1.93%,87.83±0.48% in 72 hours. There was significant difference between treated groups and control cells in different times (P<0.05) and various concentrations (P<0.05). At the same time, flow cytometry revealed that DMS could induce the apoptosis of SGC7901 cells in a concentration-dependent manner and the apoptosis rate was 9.08±2.04%, 21.13±3.07%, 35.49±4.12% with various concentrations of DMS(1,5,25)μmol/L in 12 hours. It was significantly higher than that of control cells (1.48±0.39%, P<0.05).Conclusion: 1, DMS can effect the expression of SPHK1 gene in SGC7901 cell. SPHK1 plays a key role in regulating the proliferation and apoptosis of SGC7901 cell. 2, DMS can inhibit proliferation in a concentration and time-dependent manner in SGC7901 cell. 3, DMS can induce apoptosis in a concentration- dependent manner in SGC7901 cell.