ABSTRACT
@# Objective: To investigate the influence of inhibiting expression of polyamine-modulated factor (PMF-1) on the antitumor effect of glucocorticoid dexamethasone (DEX) in human cervical cancer Caski cells. Methods: siRNAs which target human PMF-1 gene were designed and synthesized, and their effect on the expression of PMF-1 in Caski cells was evaluated by Western blotting. The PMF-1 down-regulated and control Caski cells were treated with DEX, and then the affect of PMF-1 down regulation on the sensitivity of the tumor cells to DEX was analyzed. MTT method was used to detect cell proliferation, flow cytometry was used to analyze cell cycle, Western blotting method was used to evaluate expression level of glucocorticoids receptor (GR), and HPLC was used to analyze intracellular polyamine content. Results: The transient transfection of Caski cells with siRNAwhich targets PMF-1 gene can significantly reduce the expression level of PMF-1 protein. Compared with the control cells, treating PMF-1 down-regulated Caski cells with DEX can more effectively inhibit cell proliferation（P<0.01), up regulate GR expression, arrest cell cycle at G2 stage（P<0.01), and also significantly reduce intracellular polyamine level（P<0.01). Conclusion：Inhibiting PMF-1 expression can enhance antitumor pharmacological activity of DEX against human cervical cancer cells, and the underlying mechanism may be related with enhanced cell cycle inhibition and decreased intracellular polyamine level.