HMME-PDT对人舌鳞癌Tca8113细胞的作用及影响因素初步研究

摘要

目的:初步探讨血卟啉单甲醚(HMME)介导的光动力疗法(HMME-PDT)对人舌鳞癌Tca8113细胞的作用及可能的影响因素.方法:以HMME作为光敏剂、发光二极管(LED)为光源的光动力疗法作用于Tca8113细胞.采用MTT法分别检测光敏剂孵育时间、光敏剂浓度、光剂量及光功率密度对Tca8113细胞抑制率的影响.HE染色观察细胞形态学改变.Hoechst33342荧光染色观察细胞核凋亡情况.结果:细胞抑制率随光敏剂孵育时间延长而增大,呈时间依赖效应;并且随光敏剂浓度和光剂量增加而增大,呈浓度-光剂量依赖效应;在相同光剂量下,抑制率随光功率密度增加而增大,在高剂量时更明显.HE染色显示,与对照组相比,PDT处理组细胞密度明显降低,死细胞明显增多;Hoechst 33342荧光染色可见核染色质浓集、核固缩、核碎裂,出现凋亡小体,呈典型凋亡形态改变.结论:HMME-PDT能有效杀伤Tca8113细胞,光敏剂孵育时间、光敏剂浓度、光剂量及光功率密度以均是影响PDT疗效的重要因素,HMME-PDT主要通过凋亡方式诱导细胞死亡.%Objective: To investigate the effect of HMME-mediated PDT (HMME-PDT) on human tongue squamous cell carcinoma cell line Tca8113 and the possible factors involved. Methods: The PDT treatment on Tca8113 cells was performed in vitro using HMME as photosensitizer and light-emitting diode (LED) as light source. MTT assay was used to evaluate the incubation time and concentration of HMME, the dosages and power densities of light on the effect of the inhibition rate of Tca8113 cells. The morphologicalchanges of cells were examined by HE staining, while apoptosis of the nucleus was observed by Hoechst 33342 staining using fluorescent microscopy. Results: The inhibition rate of cells increased as the incubation time prolonged, which was in time-dependent manner, it also became higher along with the increase of HMME concentration and light doses, exhibiting concentration and light dosage-dependent manner. Under the same light dose, cell death rate raised as the power density increased. HE staining showed that cell density of PDT groups became much lower and dead cells increased significantly compared with control groups. Fluorescence microscopy after Hoechst 33342 staining exhibited typical morphologic features of apoptosis, characterized by marked chromatin condensation, nuclear pyknosis and fragmentation, and the appearance of apoptotic bodies. Conclusions: HMME-PDT could effectly induce the death of Tca8113 cells, mainly through apoptosis. The incubation time and concentration of HMME, the dosage and power density of light are key factors involved in PDT.