RESUMO
Objective To explore photodynamic therapeutic efficiency and related mechanisms of a new porphyrin-typed photodynamic therapy (PDT) drug synthesized in our lab on HGC27 and MGC803 cells.Methods Two different kinds of gastric cancer cells, HGC27 and MGC803, were chosen as cell lines to evaluate the PDT efficiency of new porphyrin-typed PDT drug based upon four group experiments: control (no drug, no light) group, drug treated group (only drug, no light), light treated group (no drug, only light) and experiment group (with drug and light at the same time). Bleaching method was used to evaluate the photostability of new porphyrin-typed PDT drug upon repititive illumination. MTT assay was carried out to test the survival rate of tumor cells after PDT. Cofocal laser scanning microscope (CLSM) was applied to observe subcellular localization of drug in HGC27 and MGC803 cells (mitochondria and lysosome). Results New porphyrin-typed PDT drug has good stability to light, no toxicity on HGC27 and MGC803 cells without light (P>0.05), while intense lethal effect was observed upon light illumination (P<0.05). The peak efficacy appeared when concentration is 3.12 μmol/L for both HGC27 and MGC803 cells and the new porphyrin-typed PDT drug localizes in lysosome other than traditional mitochondrion. Conclusion New porphyrin-typed PDT drug is a good photodynamic therapeutic sensitizer for HGC27 and MGC803 tumor cells.