Objective: To study the killing effects of oxymatrine (OM) on a human colon cancer cell line, SW1116, and evaluate its antineoplastic mechanism.
Methods: Methyl thiazolyl tetrazolium (MTT) analysis, flow cytometry, polymerase chain reaction (PCR)-enzyme linked immunosorbent assay (ELISA) and RT-PCR methods were used respectively to determine the killing effects of OM and its influence on cell cycle distribution, telomerase activity and the expressions of hTERT, c-myc, p53 and mad1 in SW1116 cells.
Results: Oxymatrine exhibited dose-dependent killing effects on SW1116 cells and induced G1/G0-phase arrest. It suppressed the telomerase activity of the cells in a dose- and time-dependent manner. After OM administration, the expression of hTERT in the SW1116 cells decreased, those of p53 and mad1 increased, and the expression of c-myc was unchanged.
Conclusions: Oxymatrine has dose-dependent killing effects on SW1116 cells and its antineoplastic activity might be attributed to inhibition of telomerase activity by means of its effects on hTERT and the upstream regulating genes.