School of Chinese Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong, China.
RITS and NWU Joint Laboratory for New Drugs Research of TCM, Research Institute of Tsinghua University in Shenzhen, Shenzhen 518000, China.
Acta Pharmacol Sin. 2014 Jan;35(1):113-23. doi: 10.1038/aps.2013.162. Epub 2013 Dec 16.
The purpose of the present study was to investigate the anticancer activity of bornyl caffeate in the human breast cancer cell line MCF-7.
The cell viability was determined using the MTT assay, and apoptosis was initially defined by monitoring the morphology of the cell nuclei and staining an early apoptotic biomarker with Annexin V-FITC. The mitochondrial membrane potential was visualized by JC-1 under fluorescence microscopy, whereas intracellular reactive oxygen species (ROS) were assessed by flow cytometry. The expression of apoptosis-associated proteins was determined by Western blotting analysis.
Bornyl caffeate induced apoptosis in MCF-7 cells in a dose- and time-dependent manner. Consistently, bornyl caffeate increased Bax and decreased Bcl-xl, resulting in the disruption of MMP and subsequent activation of caspase-3. Moreover, bornyl caffeate triggered the formation of ROS and the activation of the mitogen-activated protein (MAP) kinases p38 and c-Jun N-terminal kinase (JNK). Antioxidants attenuated the activation of MAP kinase p38 but barely affected the activation of JNK. Importantly, the cytotoxicity of bornyl caffeate was partially attenuated by scavenging ROS and inhibited by MAP kinases and caspases.
The present study demonstrated that bornyl caffeate induced apoptosis in the cancer cell line MCF-7 via activating the ROS- and JNK-mediated pathways. Thus, bornyl caffeate may be a potential anticancer lead compound.
本研究旨在探讨莰烯咖啡酸酯在人乳腺癌 MCF-7 细胞系中的抗癌活性。
采用 MTT 法测定细胞活力,通过观察细胞核形态和用 Annexin V-FITC 染色早期凋亡标志物初步定义细胞凋亡。荧光显微镜下通过 JC-1 可视化线粒体膜电位,通过流式细胞术评估细胞内活性氧(ROS)。通过 Western blot 分析测定凋亡相关蛋白的表达。
莰烯咖啡酸酯以剂量和时间依赖的方式诱导 MCF-7 细胞凋亡。一致地,莰烯咖啡酸酯增加 Bax 并减少 Bcl-xl,导致 MMP 破坏和随后 caspase-3 的激活。此外,莰烯咖啡酸酯引发 ROS 的形成和丝裂原激活蛋白激酶(MAP)激酶 p38 和 c-Jun N-末端激酶(JNK)的激活。抗氧化剂减弱了 MAP 激酶 p38 的激活,但几乎不影响 JNK 的激活。重要的是,通过清除 ROS 部分减弱了莰烯咖啡酸酯的细胞毒性,并通过 MAP 激酶和半胱天冬酶抑制了其活性。
本研究表明,莰烯咖啡酸酯通过激活 ROS 和 JNK 介导的途径诱导 MCF-7 癌细胞系凋亡。因此,莰烯咖啡酸酯可能是一种有潜力的抗癌先导化合物。