OBJECTIVETo investigate the effect and mechanism of Qingdu Suppository (QDS) in suppressing the growth of SiHa cell of cervical carcinoma on the cytobiologic and molecular biologic level.

METHODSSiHa cells were cultured in media with serum containing different concentrations of QDS and blank serum, as well as serum containing various Chinese herbal or Western drugs as positive control. SiHa cell growth and proliferation was determined by MTT assay, the cell cycle and apoptosis were analyzed by flow cytometry technique, and the expression of proto-oncogene MDM2 detected semi-quantitatively by RT-PCR.

RESULTSThe amount of cells decreased after cultured with drug-containing serum 8% in concentration, with the highest inhibitory effect shown by drug-containing serum after acting for 72 h, which was significantly different to that in the control group (P < 0.01). Among the various time phases of cell cycle, the percentage of cells in S phase was significantly decreased. Drug-containing serum showed somewhat effect on cell apoptosis, but no obvious regularity could be found. RT-PCR showed significant decrease of MDM2 expression.

CONCLUSIONQDS containing serum could not only directly suppress the growth of cervical carcinoma cells, but also inhibit the tumor by the molecular mechanism of down-regulating MDM2 gene expression.