光动力疗法对人小细胞肺癌H446细胞杀伤效应

KILLING EFFECT OF PHOTODYNAMIC THERAPY ON HUMAN SMALL CELL LUNG CANCER H446 CELLS

目的探讨光动力疗法(PDT)对人小细胞肺癌H446细胞的杀伤效应及其作用机制。方法实验分为空白对照组、单纯光敏剂组、单纯光照组和血卟啉衍生物(HPD)-PDT组。单纯光敏剂组加入HPD孵育;单纯光照组用630 nm激光照射;HPD-PDT组先用HPD孵育,再应用630 nm激光照射。采用CCK8法检测细胞活力,Hoechst 33258染色、流式细胞术检测细胞凋亡,实时荧光定量PCR(RT-PCR)检测细胞Bax、Bcl-2和Caspase-9 mRNA的表达水平。结果单独给予光敏剂或者激光照射对H446细胞无明显杀伤作用,二者联合时随着光敏剂浓度的增加和激光功率密度的增大杀伤效应更明显。RT-PCR检测结果显示,与各对照组相比较,HPD-PDT组Bax、Caspase-9 mRNA表达水平明显上调(F=445.426、1765.177,P<0.05),而Bcl-2 mRNA表达水平明显下调(F=171.193,P<0.05)。结论PDT对小细胞肺癌H446细胞有显著的体外杀伤效应,其作用机制可能与上调Bax、Caspase-9 mRNA水平以及下调Bcl-2 mRNA水平有关。

Objective To investigate the killing effect of photodynamic therapy(PDT)on human small cell lung cancer H446 cells and its mechanism.Methods H446 cells were divided into blank control group,photosensitizer alone group,laser irradiation alone group,and hematoporphyrin derivative(HPD)-PDT group.The photosensitizer alone group was incubated with HPD.The laser irradiation alone group was irradiated with 630 nm laser.The HPD-PDT group was incubated with HPD first,followed by irradiating with 630 nm laser.Cell Counting Kit-8 assay was used to determine the cell viability of H446 cells.Hoechst 33258 staining and flow cytometry were used to determine the apoptosis of H446 cells.Quantitative real-time polymerase chain reaction(qRT-PCR)was used to measure the mRNA expression levels of Bax,Bcl-2,and Caspase-9.Results The photosensitizer alone or laser irradiation alone had no obvious killing effect on H446 cells.When they were used in combination,the killing effect became obvious with the increases in photosensitizer concentration and laser power density.The results of qRT-PCR showed that compared with the other three groups,the HPD-PDT group had significantly up-regulated expression levels of Bax and Caspase-9 mRNA(F=445.426,1765.177;P<0.05)and a significantly down-regulated expression level of Bcl-2 mRNA(F=171.193,P<0.05).Conclusion PDT has a significant killing effect on small cell lung cancer H446 cells.Its mechanism is rela-ted to the up-regulation of Bax and Caspase-9 mRNA expression levels and the down-regulation of Bcl-2 mRNA expression level.