| Objective:To study the inhibitory effect of SN-38in combination with lobaplatin onhuman gastric cancer cells (SGC-7901) in vitro,and to evaluate whether thetwo drugs could influence the Bcl-2protein expression levels of SGC-7901cells,whether there is a synergistic effect.Methods:1. Cell culture SGC-7901cells were incubated in vitro with RPMI1640culture develop with containing10%fetal bovine serum, and penicillin,streptomycin100UmL-1.0.25%trypsin was used to subculture,cells inlogarithmic growth phase cells were used to experiment.2.(1) Cell morphological observation To observe the morphology ofSGC-7901cells,which were incubated in vitro with SN-38and Lobaplatin atdifferent concentrations in combination or separately for different times incombination or separately under inverted microscope.(2) The inhibition ratesof SGC-7901cells by treatment with SN-38and Lobaplatin at differentconcentration and times in combination or separately were determined byMTT assay.Combination index(CI) were used to analysis the interactiverelations between the combined drugs.(3) Cell apoptosis were determined byflow cytometry.(4) Western blot was used to detect the Bcl-2proteinexpression of SGC-7901cells by SN-38and Lobaplatin alone or incombination.3. Statistical analysis: Statistical analysis was performed by usingSPSS17.0software package.All datas were expressed as mean±standarddeviation(x±s),variance analysis was used for overall analysis. The t test was applied in the intergroup comparison. P <0.05was statistically significantdifference.Results:1. Cell morphological observation: Very few SGC-7901cells bytreatment with SN-38(0.3125μg/ml) came off after48h, most of the cellswere still attached. Exfoliated cells and cell debris with increasing drugconcentration, most of the cell came off by treatment with SN-38(40μg/ml).Similarly, the effects of low concentration lobaplatin (0.3125μg/ml) was notobvious.The exfoliated cells gradually increased with extended time andincreased concentration,when the concentration of lobaplatin was40μg/ml, allthe cells came off and dead at48h.2. MTT results: The inhibition effects of SN-38and Lobaplatin incombination or separately on SGC-7901cells were enhanced with increasedconcentrations and extended time. The difference was statistically significant(P <0.05). The CI of SN-38plus lobaplatin were lower than0.8at48h and72h, which indicated that there were synergistic effects when two drugs wereused in combination.3.Flow cytometry results: The apoptosis rate of SGC-7901cells of20μg/ml SN-38and5μg/ml Lobaplatin were46.7%±3.0%,54.5%±2.3%,respectively at48h，significantly higher than that of control group(P<0.01),The apoptosis rates of combination group was82.3%±1.7%，significantlyhigher than that of SN-38or Lobaplatin group(P<0.01).4.Western blot: The result showed that compare with the control group，the expression of Bcl-2proteins in SGC-7901cells by treatment with SN-38and Lobaplatin were significantly lower.The levels of Bcl-2protein werereduced with the increased drug concentration, there were significantdifferences among the experssion of Bcl-2protein caused by differentconcentrations of two drugs.(P<0.05)Conclusion:1. SN-38, Lobaplatin can inhibit the proliferation of SGC-7901cells invitro.The antitumor effects were concentration-dependent and Time-dependent. There are evident synergetic effects when two drugs are used in combination.2. SN-38, Lobaplatin can induce SGC-7901cells apoptosis.The apoptosisrate of is significantly higher，when two drugs are used in combination.3. It is presumed that the two drugs may inhibit the proliferation ofSGC-7901cells in vitro by inhibit the expression of Bcl-2protein. |
PDF Full Text Request