中文摘要：

目的：研究新型光敏剂叶绿素衍生物4（chlorophyll derivative，CPD4）对人乳腺癌细胞系T47D和MCF-7体外光动力杀伤效应，并奸机理进行初步探讨。方法：采用激光共聚焦荧光显微镜结合荧光探针标记技术观察光敏剂在细胞内分布及亚细胞定位；将终浓度分别为2．5、2．O、1．5、1．0、0．5μg／mL的CPD4加入到T47D及MCF-7细胞培养皿中，孵育2h后用670nm半导体激光治疗仪照射，光剂量为10J／cm^3，照毕，继续培养24h后采用染料排斥实验测定细胞的存活率。流式细胞仪Annexin V-FITC／PI双染法检测细胞死亡方式和凋亡率。实验分为四组：空白对照组、单纯光敏剂组、单纯细胞光照组，光敏剂-细胞光照组。结果：光敏剂CPD4可穿过T47D及MCF-7细胞膜进入细胞，分布在细胞膜及胞浆中，线粒体是其亚细胞分布的主要位点之一。光动力组中光敏剂浓度分别为2．5、2．0、1．5、1．0、0．5μg／mL，T47D及MCF-7细胞死亡率分别为（76．77±6．41）％、（40．51±7．28）％、（38．4±5．35）％、（17．08±0．52）％、（11．16±0．28）％、（81．67±1．53）％、（69．67±4．51）％、（45．33±4．73）％、（17．67±2．52）％、（12．00±2．00）％。Annexin V-FITC／PI法检测PDT作用24h后凋亡率分别可达36．80％及40．90％。结论：新型光敏剂CPD4分布在人乳腺癌细胞T47D及MCF-7的细胞膜及细胞浆中，线粒体是其亚细胞分布主要位点之一；光敏剂CPD4对人乳腺癌细胞T47D和MCF-7具有良好的光动力杀伤效应，呈现量效关系，诱导细胞凋亡是其主要杀伤方式。线粒体途径促进细胞凋亡可能是其光动力杀伤机制。

英文摘要：

Objective： To investigate the photodynamic effects of CPD4-mediated photodynamic therapy on breast cancer cell line T47D and MCF-7, and to discuss the possible mechanism. Methods： Human breast cancer cells of the line T47D were co-cultured with CPD4, Rhodamine-123, and mitochondria fluorescence probe dyes. Laser scanning confocal fluorescence microscope was applied to collect the fluorescence of the photosensitizer and the probes and to image the cells. T47D and MCF-7 cells were cultured and divided into 4 groups including the blank control group, the laser irradiation group without photosensitizer, the photosensi- tizer group without irradiation, and the PDT group. Dye exclusion method was applied to detect the death rate of T47D and MCF-7 cells. Apoptotic ratio and the characteristics of cell death was analyzed by Annexin V-FITC/PI double labelled staining assay. Results： The fluorescence of the photosensitizer and that of the probes were observed in the cell membrane and cytoplasm and in the peri-nuclear region, mainly in the mitochondria of the T47D and MCF-7 cells. The death rate of T47D and MCF-7 cells treated with 2.5, 2.0, 1.5.1.0,and 0.5 ug/mL CPD4-PDT were 76.77%±6.41, 40.51%±7.28, 38.4%±5.35%, 17.08%±0.52, 11.16%±0.28, 81.67%±1.53, 69.67%±4.51, 45.33%±4.73, 17.67%±2.52, and 12.00%±2.00, respectively. Conclusion： CPD4 is localized in the cell membrane and cytoplasm, mainly in the mitochondria of T47D and MCF-7 cells. PDT has a significant killing effect on human breast cancer cell lines in vitro, and its relative inhibitory rate appears to be correlated with the dose of sensitizer.