郝剑，吴雄志(天津医科大学肿瘤医院国家肿瘤临床医学研究中心天津市“肿瘤防治”重点实验室，天津300060)

褐藻多糖对乳腺癌细胞活性的影响及机制探讨

郝剑，吴雄志
(天津医科大学肿瘤医院国家肿瘤临床医学研究中心天津市“肿瘤防治”重点实验室，天津300060)

摘要:目的观察褐藻多糖对人乳腺癌细胞株MCF-7、MDA-MB-231细胞活性的影响，并探讨其作用机制。方法将对数生长期的MCF-7、MDA-MB-231细胞(观察A组、B组)分别加入100、200 μg/mL褐藻多糖2 mL，对照A组、B组均加入等体积的DMEM培养基2 mL。用台盼蓝染色实验测算细胞增殖抑制率，用流式细胞仪检测细胞周期和凋亡细胞，用Western blot法检测细胞Caspase-8及磷酸化细胞外调节蛋白激酶( p-Erk)、Erk表达。结果随着褐藻多糖浓度增加、作用时间延长，观察A组、B组细胞增殖抑制率逐渐升高( P均＜0.05) ;观察A组、B组G0/G1期细胞比例升高、S期及G2期细胞比例降低，细胞凋亡率增高，褐藻多糖浓度高者变化更明显，P均＜0.05;观察A组、B组细胞Caspase-8表达升高、p-Erk表达下降，褐藻多糖浓度高者变化更明显，P均＜0.05。结论褐藻多糖可抑制MCF-7、MDA-MB-231细胞增殖，阻滞细胞周期于G0/G1期，促进细胞凋亡;该作用可能是通过上调细胞Caspase-8表达、下调p-Erk表达水平实现。

关键词:褐藻多糖;乳腺癌;细胞周期;细胞凋亡;半胱氨酸天冬氨酸蛋白酶8;细胞外调节蛋白激酶doi: 10.3969/j.issn.1002-266X.2015.30.002

Effects of Fucoidan on cell viability of breast cancer and its mechanism

HAO Jian，WU Xiong-zhi
( Tianjin Medical University Cancer Institute and Hospital，National Clinical Research Center for Cancer，Key Laboratory of Cancer Prevention and Therapy，Tianjin 300060，China)

Abstract:Objective To observe the effects of Fucoidan on cell viability of breast cancer cell lines MCF-7 and MDAMB-231 and to investigate its possible mechanism.Methods The breast cancer cell lines MCF-7 and MDA-MB-231 in the logarithmic phase ( observation group A and B) were respectively treated with 2 mL Fucoidan ( 100 ug/mL and 200 ug/mL).The control group A and B were treated with the same volume of DMEM culture medium.The cell proliferation inhibition rate was detected by Trypan blue staining，cell cycle and apoptosis cells were analyzed by flow cytometry，and the expression of Caspase-8，phosphorylation Erk ( p-Erk) and total Erk was detected by Western blotting.Results With the increased Fucoidan concentration and the prolonged time，the cell proliferation inhibition rates of the observation groups A and B were increased ( all P＜0.05)，the cell proportion in the G0/G1phase of the observation groups A and group B was increased，the cell proportion in the S phase and G2was reduced，the apoptosis rate was increased，and the changes in the high concentration Fucoidan group were more significant ( all P＜0.05).The expression of Caspase-8 was increased and the Erk expression was decreased in the observation groups A and B，and the changes in the high concentration Fucoidan group were more significant ( all P＜0.05).Conclusion Fucoidan could inhibit the proliferation of MCF-7 and MDA-MB-231 cell lines，arrest the breast cells in G0/G1phase，and also promote the apoptosis.This mechanism may be achieved by activating the expression of Caspase-8 and down-regulating the p-Erk expression.

Key words:Fucoidan，breast carcinoma; cell cycle; apoptosis; caspase;extracellular signal-regulated kinases

褐藻是一种软坚散结中药，褐藻多糖是其主要活性成分。褐藻多糖具有抗氧化、抗肿瘤、抗病毒、抗血栓、降血脂、调节免疫等多种功能［1～5］，但具体作用机制尚不清楚。细胞凋亡具有内源性和外源性

两条信号通路，两条信号通路最终均会激活凋亡蛋白Caspase-8［6］。……