Lee Chiu-Fang, Chiang Ni-Na, Lu Yao-Hua, Huang Yu-Syuan, Yang Jai-Sing, Tsai Shih-Chang, Lu Chi-Cheng, Chen Fu-An
Department of Pharmacy, Kaohsiung Veterans General Hospital Pingtung Branch, Pingtung 912, Taiwan.
Department of Pharmacy and Master Program, Tajen University, Pingtung 907, Taiwan.
Biomedicine (Taipei). 2018 Sep;8(3):15. doi: 10.1051/bmdcn/2018080315. Epub 2018 Aug 24.
Benzyl isothiocyanate (BITC), a component of dietary food, possesses a powerful anticancer activity. Previous studies have shown that BITC produces a large number of intracellular reactive oxygen species (ROS) and increases intracellular Ca release from endoplasmic reticulum (ER), leading to the activation of the apoptotic mechanism in tumor cells. However, there is not much known regarding the inhibitory effect of BITC on cisplatin-resistant oral cancer cells. The purpose of this study was to examine the anticancer effect and molecular mechanism of BITC on human cisplatin-resistant oral cancer CAR cells. Our results demonstrated that BITC significantly reduced cell viability of CAR cells in a concentration- and time-dependent manner. BITC was found to cause apoptotic cell shrinkage and DNA fragmentation by morphologic observation and TUNEL/DAPI staining. Pretreatment of cells with a specific inhibitor of pan-caspase significantly reduced cell death caused by BITC. Colorimetric assay analyses also showed that the activities of caspase-3 and caspase-9 were elevated in BITC-treated CAR cells. An increase in ROS production and loss of mitochondria membrane potential (ΔΨm) occurred due to BITC exposure and was observed via flow cytometric analysis. Western blotting analyses demonstrated that the protein levels of Bax, Bad, cytochrome c, and cleaved caspase-3 were up-regulated, while those of Bcl-2, Bcl-xL and pro-caspase-9 were down-regulated in CAR cells after BITC challenge. In sum, the mitochondria-dependent pathway might contribute to BITC-induced apoptosis in human cisplatin-resistant oral cancer CAR cells.
异硫氰酸苄酯（BITC）是一种膳食成分，具有强大的抗癌活性。先前的研究表明，BITC可产生大量细胞内活性氧（ROS），并增加细胞内钙离子从内质网（ER）的释放，从而导致肿瘤细胞凋亡机制的激活。然而，关于BITC对顺铂耐药口腔癌细胞的抑制作用，目前所知甚少。本研究的目的是探讨BITC对人顺铂耐药口腔癌CAR细胞的抗癌作用及其分子机制。我们的结果表明，BITC以浓度和时间依赖性方式显著降低CAR细胞的活力。通过形态学观察和TUNEL/DAPI染色发现，BITC可导致凋亡细胞皱缩和DNA片段化。用泛半胱天冬酶特异性抑制剂预处理细胞可显著降低BITC引起的细胞死亡。比色法分析还表明，BITC处理的CAR细胞中半胱天冬酶-3和半胱天冬酶-9的活性升高。通过流式细胞术分析观察到，BITC处理导致ROS产生增加和线粒体膜电位（ΔΨm）丧失。蛋白质印迹分析表明，BITC处理后的CAR细胞中，Bax、Bad、细胞色素c和裂解的半胱天冬酶-3的蛋白水平上调，而Bcl-2、Bcl-xL和前体半胱天冬酶-9的蛋白水平下调。总之，线粒体依赖性途径可能在BITC诱导的人顺铂耐药口腔癌CAR细胞凋亡中发挥作用。
