Anti-proliferation effects of dammar-24-ene-3β-acetate-20S-ol on gastric cancer cells / 医学研究生学报

ABSTRACT

Objective Based on the previous research that the ethanolic extract from traditional Chinese medicine fructus forsythiae (Lianqiao) can obviously inhibit cancer cells in vitro, the article aimed to investigate the anti-proliferation effects of dammar-24-ene-3β-acetate-20S-ol (DM) extracted from fructus forsythiae on gastric cancer cells and its mechanism.Methods MTT assay was used to assess the anti-proliferation effects of DM on gastric cancer cells including SGC-7901, BGC-823, and MKN-45 in vitro.There were MKN-45 control group and its low dose and high dose groups, BGC-823 control group and its low dose and high dose groups, SGC-7901 control group and its low dose and high dose groups in the experiment.Flow cytometry was used to analyze the cell apoptosis rate.Cellquest software was used to analyze the results and record the ratio of cells at different cycles.DCFH-DA probe was applied to detect the ROS levels of blank control group, docetaxol group and DM group.The reaction system of microtubule assembly test was set with 10?mol/L docetaxol, 50 or 100 μmol/L DM final density and no medicine in blank control group.The readings of UV spectrophotometer were recorded.Microtubule assembly assay and microtubule immunofluorescence staining were applied to investigate the effects of DM on microtubule system.Results The inhibition ratio of 50 μg/L DM on the proliferation three gastric cell lines were all above 80%, with IC50s of MKN-45 11.72±1.35 μg/mL, BGC-823 17.19±0.82 μg/mL, SGC-7901 7.55±0.79 μg/mL.8 days′ low density culturing at 48 hours after 2 μg/mL DM treatment, compared with control group, the number of cell clones significantly reduced without much change in clone size, while 48 hours after 10 μg/mL DM treatment, besides a few clones of BGC-823, there were just several megascopic clones of SGC-7901 and MKN-45.In comparison with apoptotic cell ratio in MKN-45 control group[(21.1±2.5)%], its low dose group and high dose group resulted in significant rise of apoptotic cell ratio[(25.1±1.3)% and (55.2±2.3)%] (P0.05).In comparison with MKN-45 control group, the ratio of cells at S phase decreased in its low dose group[(14.5±2.7)% vs (12.3±3.3)%,P>0.05].In comparison with BGC-823 control group, the ratio of cells at S phase increased in its low dose group[(12.2±5.4)% vs (20.2±2.1)%,P<0.05].In comparison with SGC-7901 control group, the ratio of cells at S phase increased in its low dose group[(21.5±3.8)% vs (31.3±2.6)%,P<0.05].From the detection of intracellular active oxygen after DM treatment, dose-dependent ROS level increased in all three cell lines 48 hours after 10μg/mL and 50μg/mL DM treatment.From the results of microtubule immunofluorescence staining, 48 hours after the treatment of IC50 docetaxol and 10μg/mL DM, the fluorescence signals were in local concentration and disorder.Conclusion Dammar-24-ene-3β-acetate-20S-ol demonstrated anti-proliferation effects due to the apoptosis induced by cell cycle arrest at S phase.