Abstract:

Abstract:Objective
To investigate the effects of photodynamic therapy mediated by meso-5, 10, 15, 20-Tetrakis-(N-methyl-4-pyridyl)porphine(TMPyP4) on human ovarian carcinoma A2780 cells in vitro as well as the expression levels of MCM2 and CA-Ⅸ  mRNA in A2780 cells and to clarify the destruction mechanism of the TMPyP4-PDT on human ovarian carcinoma A2780 cells.Methods The human ovarian carcinoma A2780 cells were cultured in vitro and divided into 4 groups as follows: blank control group, simple TMPyP4 group, simple PDT group and TMPyP4-PDT group.The  increase of inhibitory effects of TMPyP4-PDT on proliferation of A2780 cells were detected by CCK-8 assay.The apoptosis of A2780 cells after treated with different concentrations of TMPyP4 were detected by flow cytometry(FCM).The morphological changes of cells in various groups were observed with HE staining under light microscope.The expression levels of MCM2 and CA-Ⅸ  mRNA were detected by RT-PCR.Results  The  inhibitory rates of cell proliferation in simple TMPyP4 group were gradually increased with the increase of the dosage(P<0.05).The increase of inhibitory rates of cell proliferation in simple PDT group was not obvious(P> 0.05).The inhibitory rates of cell proliferation in TMPyP4-PDT group were increased with the increase of the dosage and the light energy density(P<0.05).FCM analysis showed that TMPyP4-PDT could induce the apoptosis of A2780 cells; the apoptotic rates of A2780 cells were (9.46±0.04)%, (17.7±0.3)%, (25.4±0.2)%, (30.2±0.2)% and (66.3±0.3)% when the light energy density was 4 J•cm^-2 and the doses of TMPyP4 were 3, 6, 15, 30 and 60 μmol•L^-1 and the treatment time was 4 h. More adherent cells without nuclear pyknosis and nuclear fragmentation in blank control group and simple PDT group were observed under light microscope; Less adherent cells as well as nuclear pyknosis, vacuole and some cytoplasmic dissolution in simple TMPyP4 group and TMPyP4-PDT group could be observed under light microscope.RT-PCR analysis showed that compared with blank control group , the expressions of MCM2 and　CA-Ⅸ  mRNA were decreased significantly after treated with 3, 6, 15, 30 and 60 μmol?L-1 TMPyP4 for 4 h (P<0.01) under the conditions of the light energy density of 4 J?cm-2.Conclusion TMPyP4-PDT has distinctive inhibitory effects on human ovarian carcinoma A2780 cells, and the mechanism may associate with the negative regulation of the expressions of MCM2 and CA-Ⅸ .

Key words: ovarian neoplasms, A2780 cell;TMPyP4；photodynamic therapy；minichromosome maintenance proteins；carbonic anhydrase Ⅸ