Effect of 5-aminolevulinic acid mediated photodynamic therapy on proliferation and apoptosis of gastric cancer cell line MKN-45 / 肿瘤研究与临床

ABSTRACT

Objective To explore the 5-aminolevulinic acid (5-ALA) mediated photodynamic therapy (PDT) for proliferation and apoptosis of gastric cancer cell line MKN-45.Methods The human gastric cancer cell line MKN-45 was cultured in vitro.The MTT method was used to detect fixed lighting processing (laser radiation dose fixed for 25.00 J/cm2,5-ALA photosensitizer concentrations were 0 mmol/L,0.25 mmol/L,0.50 mmol/L,1.00 mmol/L,2.00 mmol/L),fixed photosensitizer concentration treatment (5-ALA photosensitizer concentrations fixed to 1.00 mmol/L,laser radiation dose were 0 J/cm2,6.25 J/cm2,12.50 J/cm2,25.00 J/cm2,50.00 J/cm2,100.00 J/cm2) of the cell apoptosis rate,and then fixed 5-ALA photosensitizer 1 mmol/L and selected the control group,5-ALA group,pure illumination group and PDT group.The promoting effect on cell apoptosis was determined by MTT,electron microscope and flow cytometry.The activity of human gastric cancer cells MKN-45 apoptosis related proteins p65 and the downstream gene regulatory protein bcl-2,bax,caspase-3 and caspase-9 were detected by using Western blot method.Results When laser radiation dose was fixed,5-ALA photosensitizer concentrations in promoting gastric cancer cell apoptosis was positively related to the dominant (P ＜ 0.01).When 5-ALA photosensitizer concentration was fixed,laser radiation dose effect had no longer dominant after 25.00 J/cm2 positive correlation (P =0.613).When 5-ALA photosensitizer concentration was fixed in 1 mmol/L,compared to control group,5-ALA group and pure illumination group,the inhibition of the MKN-45 cell proliferation in PDT group was more apparently,apoptosis rate increased obviously,signal pathways in cell apoptosis protein involved in the NF-kappa B p65 expression was reduced,the downstream gene regulation of target protein bcl-2,caspase-3 and caspase-9 expression were reduced,and bax protein expression was increased.Conclusions 5-ALA mediated photodynamic has a strong inhibitory effect on the growth of gastric cancer cell line MKN-45 in vitro.It can significantly increase the apoptosis rate of gastric cancer cells,and the effect may be carried out by activating the NF-kappa B pathway.