Department of Photodynamic and Sonodynamic Therapy, Second Affiliated Hospital, Chongqing Medical University, Chongqing, China.
Photodiagnosis Photodyn Ther. 2012 Dec;9(4):337-43. doi: 10.1016/j.pdpdt.2012.03.009. Epub 2012 May 29.
Breast cancer is a common disease which threatens the life of women. To explore an alternative modality for combating breast cancer, a light-emitting diode (LED) that activates hypocrellin B was used in the present study to investigate apoptosis induction in breast cancer MDA-MB-231 cells.
Photocytotoxicity was investigated 24h after photodynamic treatment of hypocrellin B using MTT reduction assay and light microscopy. Apoptosis was observed 6h after photodynamic treatment using flow cytometry with Annexin V/PI staining as well as fluorescent microscopy with Hoechst33258 staining. The ultrastructure of the treated cells was observed using transmission electron microscopy (TEM).
Hypocrellin B-induced photocytotoxicity in MDA-MB-231 cells exhibited a dose-dependent manner. The amount of MDA-MB-231 cells attached to the bottom of well decreased significantly after photodynamic treatment of hypocrellin B. Flow cytometry showed that the early and late apoptotic rate of MDA-MB-231 cells increased remarkably up to 17.46% and 32.80%, respectively, after treatment of LED-activated hypocrellin B. In addition, nuclear condensation, fragmentation and chromatin margination, and topical apoptotic body in the treated cells were observed by nuclear staining and TEM.
Photodynamic action of hypocrellin B irradiated by light-emitting diodes could significantly kill breast cancer cells and induce apoptotic cell death, which suggests LED-activated hypocrellin B is a promising strategy for combating breast cancer.
乳腺癌是一种严重威胁女性生命的常见疾病。为了探索一种治疗乳腺癌的新方法，本研究采用发光二极管（LED）激活竹红菌乙素，研究其诱导乳腺癌 MDA-MB-231 细胞凋亡的作用。
采用 MTT 还原试验和光镜观察竹红菌乙素光动力治疗 24 小时后的光细胞毒性。用 Annexin V/PI 染色流式细胞术和 Hoechst33258 染色荧光显微镜观察光动力治疗 6 小时后的细胞凋亡。用透射电子显微镜（TEM）观察处理细胞的超微结构。
竹红菌乙素诱导的 MDA-MB-231 细胞光细胞毒性呈剂量依赖性。竹红菌乙素光动力治疗后，贴壁于培养瓶底的 MDA-MB-231 细胞数量明显减少。流式细胞术显示，经 LED 激活的竹红菌乙素处理后，MDA-MB-231 细胞的早期和晚期凋亡率分别显著增加至 17.46%和 32.80%。此外，经核染色和 TEM 观察到处理细胞的核浓缩、碎裂和染色质边缘化以及表面凋亡小体。
发光二极管照射的竹红菌乙素的光动力作用可显著杀伤乳腺癌细胞并诱导细胞凋亡，提示 LED 激活的竹红菌乙素是治疗乳腺癌的一种有前途的策略。
