State Key Laboratory of Bioreactor Engineering and Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, PR China.
Department of Pharmacy, School of Medicine, Jiaxing University, Jiaxing, Zhejiang 314001, China.
Toxicol Appl Pharmacol. 2021 May 1;418:115484. doi: 10.1016/j.taap.2021.115484. Epub 2021 Mar 11.
The clinical use of cisplatin are limited due to its drug resistance. Thus, it is urgent to find effective combination therapy that sensitizes tumor cells to this drug. The combined chemo-photodynamic therapy could increase anti-tumor efficacy while also reduce the side effects of cisplatin. Berberine is an isoquinoline alkaloid, which has been reported to show high photosensitizing activity. In this study, we have examined the effect of a combination of cisplatin and berberine-PDT in cisplatin-resistant melanoma cells. The cytotoxic effects of berberine-PDT alone or in combination with cisplatin were tested by MTT assays. We then examined the subcellular localization of berberine with confocal fluorescence microscopy. The percentage of apoptotic cells, the mitochondrial membrane potential (Δψm) and reactive oxygen species (ROS) generation assessed using flow cytometry analysis. Western blotting used in this study to determine the expression levels of MAPK signaling pathways and apoptosis-related proteins. Experimental data revealed that the mode of cell death is the caspase-dependent mitochondrial apoptotic pathways. Excessive accumulation of ROS played a key role in this process, which is confirmed by alleviation of cytotoxicity upon pretreatment with NAC. Furthermore, we found that the combined treatment activated MAPK signaling pathway. The inhibition of p38 MAPK by pretreating with SB203580 block the combined treatment-induced apoptotic cell death. In conclusion, berberine-PDT could be used as a chemo-sensitizer by promoting cell death through activation of a ROS/p38/caspase cascade.
顺铂的临床应用受到其耐药性的限制。因此，迫切需要找到有效的联合治疗方法，使肿瘤细胞对这种药物敏感。化学-光动力联合治疗可以提高抗肿瘤疗效，同时降低顺铂的副作用。小檗碱是一种异喹啉生物碱，已被报道具有很高的光敏活性。在本研究中，我们研究了顺铂耐药黑色素瘤细胞中顺铂与小檗碱-PDT 联合应用的效果。通过 MTT 测定法检测小檗碱-PDT 单独或与顺铂联合应用的细胞毒性作用。然后，我们使用共聚焦荧光显微镜检查小檗碱的亚细胞定位。通过流式细胞术分析评估细胞凋亡的百分比、线粒体膜电位 (Δψm) 和活性氧 (ROS) 的产生。本研究中使用 Western blot 来确定 MAPK 信号通路和凋亡相关蛋白的表达水平。实验数据表明，细胞死亡的方式是依赖 caspase 的线粒体凋亡途径。ROS 的过度积累在这个过程中起关键作用，这一过程可通过 NAC 预处理减轻细胞毒性来证实。此外，我们发现联合治疗激活了 MAPK 信号通路。用 SB203580 预处理抑制 p38 MAPK 可阻断联合治疗诱导的细胞凋亡死亡。综上所述，小檗碱-PDT 可以通过激活 ROS/p38/caspase 级联反应促进细胞死亡，作为化疗增敏剂。
