Department of Hematology, Sun Yat-Sen Memorial Hospital of Sun Yat-Sen University, Guangzhou, China.
Acta Biochim Biophys Sin (Shanghai). 2011 Jan;43(1):30-7. doi: 10.1093/abbs/gmq107.
Quercetin is one of the naturally occurring dietary flavonol compounds. It is present abundantly in plants and has chemopreventive and anticancer effects. To investigate its anticancer mechanism, we examined the activity of quercetin against acute leukemia cell line, HL-60. Our results showed that quercetin inhibited cell proliferation and induced apoptosis in a time- and dose-dependent manner. Furthermore, quercetin down-regulated the expression of anti-apoptosis protein Bcl-2 and up-regulated the expression of pro-apoptosis protein Bax. Caspase-3 was also activated by quercetin, which started a caspase-3-depended mitochodrial pathway to induce apoptosis. It was also found that quercetin inhibited the expression of the cycloocygenase-2 (Cox-2) mRNA and Cox-2 protein. Taken together, these findings suggested that quercetin induces apoptosis in a caspase-3-dependent pathway by inhibiting Cox-2 expression and regulates the expression of downstream apoptotic components, including Bcl-2 and Bax. Quercetin can be a potent and promising medicine which might be safely used in leukemia therapy.
槲皮素是一种天然存在的饮食类黄酮化合物。它在植物中含量丰富，具有化学预防和抗癌作用。为了研究其抗癌机制，我们研究了槲皮素对急性白血病细胞系 HL-60 的活性。结果表明，槲皮素呈时间和剂量依赖性地抑制细胞增殖并诱导细胞凋亡。此外，槲皮素下调抗凋亡蛋白 Bcl-2 的表达，上调促凋亡蛋白 Bax 的表达。 caspase-3 也被槲皮素激活，启动 caspase-3 依赖性线粒体途径诱导细胞凋亡。还发现槲皮素抑制环氧化酶-2（Cox-2）mRNA 和 Cox-2 蛋白的表达。综上所述，这些发现表明槲皮素通过抑制 Cox-2 的表达，在 caspase-3 依赖性途径中诱导细胞凋亡，并调节包括 Bcl-2 和 Bax 在内的下游凋亡成分的表达。槲皮素可能是一种有效且有前途的药物，可安全用于白血病治疗。
