Zhao Peng, Mao Jun-Min, Zhang Shu-Yun, Zhou Ze-Quan, Tan Yang, Zhang Yu
Health Management Center, Hangzhou Sanatorium of PLA, Hangzhou, Zhejiang 310007, P.R. China.
Department of Traditional Chinese Medicine, Hangzhou Sanatorium of PLA, Hangzhou, Zhejiang 310007, P.R. China.
Oncol Lett. 2014 Aug;8(2):765-769. doi: 10.3892/ol.2014.2159. Epub 2014 May 19.
Quercetin can inhibit the growth of cancer cells with the ability to act as a 'chemopreventer'. Its cancer-preventive effect has been attributed to various mechanisms, including the induction of cell-cycle arrest and/or apoptosis, as well as its antioxidant functions. Quercetin can also reduce adipogenesis. Previous studies have shown that quercetin has potent inhibitory effects on animal fatty acid synthase (FASN). In the present study, activity of quercetin was evaluated in human liver cancer HepG2 cells. Intracellular FASN activity was calculated by measuring the absorption of NADPH via a spectrophotometer. MTT assay was used to test the cell viability, immunoblot analysis was performed to detect FASN expression levels and the apoptotic effect was detected by Hoechst 33258 staining. In the present study, it was found that quercetin could induce apoptosis in human liver cancer HepG2 cells with overexpression of FASN. This apoptosis was accompanied by the reduction of intracellular FASN activity and could be rescued by 25 or 50 μM exogenous palmitic acids, the final product of FASN-catalyzed synthesis. These results suggested that the apoptosis induced by quercetin was via the inhibition of FASN. These findings suggested that quercetin may be useful for preventing human liver cancer.
槲皮素能够抑制癌细胞生长，具备充当“化学预防剂”的能力。其防癌效果归因于多种机制，包括诱导细胞周期停滞和/或凋亡，以及其抗氧化功能。槲皮素还能减少脂肪生成。先前的研究表明，槲皮素对动物脂肪酸合酶（FASN）具有强大的抑制作用。在本研究中，对槲皮素在人肝癌HepG2细胞中的活性进行了评估。通过分光光度计测量NADPH的吸光度来计算细胞内FASN活性。采用MTT法检测细胞活力，进行免疫印迹分析以检测FASN表达水平，并通过Hoechst 33258染色检测凋亡效应。在本研究中，发现槲皮素可诱导FASN过表达的人肝癌HepG2细胞凋亡。这种凋亡伴随着细胞内FASN活性的降低，并且可以被25或50μM的外源性棕榈酸（FASN催化合成的终产物）挽救。这些结果表明，槲皮素诱导的凋亡是通过抑制FASN实现的。这些发现提示，槲皮素可能对预防人类肝癌有用。
