Effect of Oxymatrine on Proliferation and Apoptosis in Human colon Carcinoma LOVO Cells

Objective:To investigate the effect of oxymatrine(OM)on modulating proliferation and apoptosis in human colon cancer cell lines LOVO.Methods:Human colon cancer cell lines LOVO was treated with OM.The inhibitory rates were detected by MTT assay.Apoptosis rate and cell cycle distribution were analyzed by flow cytometric technique.Changes of morphology were observed by Gimmsa staining when cells were treated with OM.Effect of OM on the expression of p53 in LOVO cells was examined by real time PCR.Results:OM exhibited a clearly inhibitory effect on the growth of colon cancer cell line LOVO within the dosage from 200μg/mL to 5mg/mL.OM could inhibit the excessive proliferation of LOVO induced by LPS.In the light microscope,the number of cells was significantly reduced after the role of OM,intracellular vacuoles were significantly increased.Oxymatrine could induce apoptosis of LOVO cells and apoptotic rate amounted to about 25% after treatment with 2.0mg/mL oxymatrine for 48h.Oxymatrine could block LOVO cells in S phase and prevent cells entering into G0/G1 phase.It resulted in an obvious accumulation of S phase cells with decrease of G0/G1 phase cells.We also foundd that oxymatrine down-regulated expression of p53 gene expression.Conclusion:OM could significantly inhibit the proliferation and induce apoptosis in human colon cancer cells LOVO.The mechanisms may be related to blocking in LOVO cells in S phase,and reducing p53 mRNA expression in LOVO cells.