目的 ·探讨褐藻糖胶对多发性骨髓瘤U266细胞自噬、迁移及侵袭的影响。方法 ·褐藻糖胶处理细胞后，透射电子显微镜（TEM）观察细胞自噬小体，Transwell小室观察细胞迁移及侵袭能力，Western blotting测定LC3-Ⅱ/LC3-Ⅰ、Beclin-1、P62、MMP9、CXCR4、p-AKT/T-AKT、p-mTOR/T-mTOR蛋白表达，ELISA法检测细胞培养液中MMP9含量。结果 · ①TEM观察发现，褐藻糖胶处理组自噬小体增加。②褐藻糖胶可降低U266细胞迁移及侵袭能力，并呈现出剂量依赖性，氯喹可阻断该抑制作用。③ Western blotting结果显示，LC3-Ⅱ/LC3-Ⅰ、Beclin-1及MMP9蛋白表达随褐藻糖胶浓度增加而增加，P62、CXCR4、p-AKT/T-AKT及p-mTOR/T-mTOR蛋白表达随褐藻糖胶浓度增加而降低。④ELISA结果显示，褐藻糖胶处理组细胞培养液中MMP9的含量下降。结论 ·褐藻糖胶可诱导多发性骨髓瘤U266细胞自噬，抑制该细胞的迁移、侵袭能力。

Objective · To investigate effect of fucoidan on autophagy, migration and invasion in human multiple myeloma U266 cells. Methods · The U266 cells treated with fucoidan were cultured in vitro. The formation of autophagosomes was observed by transmission electron microscopy (TEM).Transwell assay was used to evaluate the effect of fucoidan on migratory and invasive abilities of U266 cells. The protein levels of LC3-Ⅱ/LC3-Ⅰ, Beclin-1, P62, MMP9, CXCR4, p-AKT/T-AKT, p-mTOR/T-mTOR were detected by Western blotting. MMP9 concentration in the culture medium was examined by ELISA. Results · ①Autophagosomes increased in fucoidan-treated cells compared with control group under TEM. ② Migratory and invasive abilities were inhibited by fucoidan in a dose-dependent manner, which were suppressed by chloroquine. ③Western blotting demonstrated that expression of LC3-Ⅱ/LC3-Ⅰ, Beclin-1 and MMP9 increased in fucoidan-treated cells, while P62, CXCR4, p-AKT/T-AKT and p-mTOR/T-mTOR decreased compared with control group. ④The result of ELISA showed that MMP9 concentration in the culture medium of fucoidan-treated cells significantly decreased. Conclusion · Fucoidan induces autophagy and inhibits migration and invasion in U266 cells.