Li Yi Rong, Li Shiming, Ho Chi-Tang, Chang Ya-Han, Tan Kok-Tong, Chung Ting-Wen, Wang Bing-Yen, Chen Yu-Kuo, Lin Chi-Chen
a Institute of Biomedical Science and Rong Hsing Research Center for Translational Medicine, National Chung-Hsing University , Taichung , Taiwan.
b Hubei Key Laboratory for Processing and Application of Catalytic Materials, Huanggang Normal University , Hubei , China.
Cancer Biol Ther. 2016;17(1):48-64. doi: 10.1080/15384047.2015.1108491.
Tangeretin, a major phytochemicals in tangerine peels--an important Chinese herb, has been found to have anti-carcinogenic properties. To improve bioavailability and increase potency of tangeretin, its derivative, 5-acetyloxy-6,7,8,4'-tetramethoxyflavone (5-AcTMF), has been synthesized and shown potent inhibition of proliferation activity against human breast and leukemia cancer cell lines. In this study, we have further investigated the anticancer effects of 5-AcTMF on CL1-5 non-small cell lung cancer cells (NSCLC) both in vitro and in vivo and demonstrated that 5-AcTMF effectively inhibited cancer cell proliferation, induced G2/M-phase arrest associated with cdc2 and CDC25c and increased in the apoptotic cells associated with caspase activation, down regulation of Bcl-2, XIAP and Survivn, inducing release of cytochrome c into the cytosol and disruption of mitochondrial membrane potential. We also found that 5-AcTMF treatment of CL1-5 activated autophagy, indicated by triggered autophagosome formation and increased LC3-II levels and formation of LC3 puncta. Moreover, we also found that 5-AcTMF lowered phophoatidylinositol 3-kinase/AKT/mTOR signaling pathway. Over-expression of AKT by AKT cDNA transfection decreased 5-AcTMF mediated apoptosis and autophagy, supporting the induction of apoptosis and autophagy by inhibition of AKT pathway. In an animal study, 5-AcTMF effectively delayed tumor growth in a nude mouse model of CL1-5 xenografts without observed adverse effect. Immunohistochemistry Analysis indicated that 5-AcTMF induced CL1-5 cell apoptosis and autophagy in vivo. Taken together, these data demonstrate that 5-AcTMF is a novel small molecule agent that can inhibit NSCLC cell proliferation, and induce G(2)/M phase arrest and via the mitochondrial apoptotic pathway and autophagy.
陈皮苷是陈皮（一种重要的中药材）中的主要植物化学成分，已被发现具有抗癌特性。为了提高陈皮苷的生物利用度并增强其效力，合成了其衍生物5-乙酰氧基-6,7,8,4'-四甲氧基黄酮（5-AcTMF），并显示出对人乳腺癌和白血病癌细胞系增殖活性的有效抑制作用。在本研究中，我们进一步研究了5-AcTMF对CL1-5非小细胞肺癌细胞（NSCLC）的体内外抗癌作用，证明5-AcTMF有效抑制癌细胞增殖，诱导与cdc2和CDC25c相关的G2/M期阻滞，并增加与半胱天冬酶激活、Bcl-2、XIAP和Survivin下调相关的凋亡细胞，诱导细胞色素c释放到细胞质中并破坏线粒体膜电位。我们还发现，5-AcTMF处理CL1-5可激活自噬，表现为触发自噬体形成、增加LC3-II水平和形成LC3斑点。此外，我们还发现5-AcTMF降低了磷脂酰肌醇3-激酶/AKT/mTOR信号通路。通过AKT cDNA转染过表达AKT可降低5-AcTMF介导的凋亡和自噬，支持通过抑制AKT途径诱导凋亡和自噬。在一项动物研究中，5-AcTMF在CL1-5异种移植裸鼠模型中有效延缓肿瘤生长，未观察到不良反应。免疫组织化学分析表明，5-AcTMF在体内诱导CL1-5细胞凋亡和自噬。综上所述，这些数据表明5-AcTMF是一种新型小分子药物，可抑制NSCLC细胞增殖，并通过线粒体凋亡途径和自噬诱导G(2)/M期阻滞。
