He Mingyan, Hou Jiayun, Wang Lingyan, Zheng Minghuan, Fang Tingting, Wang Xiangdong, Xia Jinglin
Liver Cancer Institute, Zhongshan Hospital, Fudan University, Shanghai, China.
Clinical Science Institute, Zhongshan Hospital, Fudan University, Shanghai, China.
Oncotarget. 2017 Jun 27;8(26):42136-42148. doi: 10.18632/oncotarget.15010.
Actinidia chinensis Planch root extract (acRoots) is a traditional Chinese medicine with anti-tumor efficacy. To investigate the mechanisms responsible for this activity, we examined the effects of acRoots on cholesterol metabolism in hepatocellular carcinoma (HCC). mRNA chip analysis was used to identify the metabolic genes regulated by acRoots. The effects of acRoots on cholesterol synthesis and uptake were evaluated by measuring intracellular cholesterol levels and 3,3'-dioctadecylindocarbocyanine-labeled low-density lipoprotein (Dil-LDL) uptake. Expression of metabolic genes was analyzed using quantitative reverse transcription PCR, western blotting, and flow cytometry. acRoots reduced the viability of LM3 and HepG2 cells at 5 mg/mL and HL-7702 cells at 30 mg/mL. Gene expression profiling revealed that treatment with acRoots altered expression of genes involved in immune responses, inflammation, proliferation, cell cycle control, and metabolism. We also confirmed that acRoots enhances expression of PCSK9, which is important for cholesterol metabolism. This resulted in decreased LDL receptor expression, inhibition of LDL uptake by LM3 cells, decreased total intracellular cholesterol, and reduced proliferation. These effects were promoted by PCSK9 overexpression and rescued by PCSK9 knockdown. Our data demonstrate that acRoots is a novel anti-tumor agent that inhibits cholesterol metabolism though a PCSK9-mediated signaling pathway.
中华猕猴桃根提取物（acRoots）是一种具有抗肿瘤功效的传统中药。为了探究其抗肿瘤活性的作用机制，我们研究了acRoots对肝细胞癌（HCC）胆固醇代谢的影响。采用mRNA芯片分析来鉴定受acRoots调控的代谢基因。通过测量细胞内胆固醇水平和3,3'-二辛基吲哚碳菁标记的低密度脂蛋白（Dil-LDL）摄取来评估acRoots对胆固醇合成和摄取的影响。使用定量逆转录PCR、蛋白质免疫印迹法和流式细胞术分析代谢基因的表达。acRoots在5 mg/mL时可降低LM3和HepG2细胞的活力，在30 mg/mL时可降低HL-7702细胞的活力。基因表达谱分析显示，acRoots处理可改变参与免疫反应、炎症、增殖、细胞周期调控和代谢的基因表达。我们还证实acRoots可增强对胆固醇代谢重要的PCSK9的表达。这导致低密度脂蛋白受体表达降低、LM3细胞对低密度脂蛋白摄取的抑制、细胞内总胆固醇减少以及增殖降低。这些作用通过PCSK9过表达得以促进，并通过PCSK9基因敲低得以挽救。我们的数据表明，acRoots是一种新型抗肿瘤药物，它通过PCSK9介导的信号通路抑制胆固醇代谢。
