Hsu Yi-Chiang, Weng Hsiao-Ching, Lin ShiuRu, Chien Yie W
InnovaTherapeutics Research Center, College of Pharmacy, Kaohsiung Medical University, Kaohsiung, Taiwan.
J Agric Food Chem. 2007 Oct 3;55(20):8213-22. doi: 10.1021/jf070684v. Epub 2007 Aug 31.
Curcumin, which is a bright orange-yellow pigment of turmeric with antioxidant properties, has been shown to produce a potent preventative action against several types of cancers in recent studies. It has also been reported to protect the development of colon tumor in animals being fed with carcinogen. In the colon cancer cells, curcumin was illustrated to inhibit cell proliferation and induce apoptosis. As an antioxidant, it acts as an anti-inflammatory as well as an antitumor agent. Curcumin has been detected to exist in nature in the form of curcuminoids, a mixture of curcumin, the major component, with two of its related demethoxy compounds (demethoxycurcumin and bisdemethoxycurcumin). In the present study, we have investigated the antiproliferation and induced apoptosis effects of curcuminoids on colon cancer, using the primary cancer cells isolated from Taiwanese colon cancer patients as the model for colorectal cancer. Results showed that curcuminoids inhibited cell proliferation and induced apoptosis of these human primary colon cancer cells. The effects were observed in a dose-dependent manner as dose increased from 12.5 to 100 microM. With the aim of furthering the fundamental understanding of the mechanisms underlying the antiproliferation and induced apoptosis effects of curcuminoids on these human colon cancer cells, we developed a sensitive, rapid, and reproducible assay method based on high-performance liquid chromatography (HPLC). This HPLC technique developed was found to successfully determine, in a quantitative manner, the cellular uptake of curcuminoids. The uptake of these curcuminoids by the colon cancer cells was shown to increase as the dose of curcuminoids was increased. The observations of inhibited proliferation and increased apoptosis in the colon cancer cells appeared to be associated with the cellular uptake of curcuminoids.
姜黄素是姜黄中一种亮橙黄色的具有抗氧化特性的色素，近期研究表明它对多种癌症具有强大的预防作用。据报道，它还能保护喂食致癌物的动物的结肠肿瘤发展。在结肠癌细胞中，姜黄素被证明可抑制细胞增殖并诱导细胞凋亡。作为一种抗氧化剂，它兼具抗炎和抗肿瘤作用。已检测到姜黄素在自然界中以姜黄素类化合物的形式存在，姜黄素类化合物是一种混合物，主要成分姜黄素与其两种相关的去甲氧基化合物（去甲氧基姜黄素和双去甲氧基姜黄素）混合而成。在本研究中，我们以从台湾结肠癌患者分离出的原发性癌细胞作为结直肠癌模型，研究了姜黄素类化合物对结肠癌的抗增殖和诱导凋亡作用。结果表明，姜黄素类化合物抑制了这些人原发性结肠癌细胞的增殖并诱导其凋亡。随着剂量从12.5微摩尔增加到100微摩尔，观察到的这些作用呈剂量依赖性。为了进一步深入了解姜黄素类化合物对这些人结肠癌细胞的抗增殖和诱导凋亡作用的潜在机制，我们开发了一种基于高效液相色谱（HPLC）的灵敏、快速且可重复的检测方法。发现所开发的这种HPLC技术能够成功地定量测定姜黄素类化合物的细胞摄取量。随着姜黄素类化合物剂量的增加，结肠癌细胞对这些姜黄素类化合物的摄取量也增加。在结肠癌细胞中观察到的增殖抑制和凋亡增加似乎与姜黄素类化合物的细胞摄取有关。
