轴抑制因子通过β-catenin调控MMP7、MMP9影响淋巴瘤细胞的侵和袭转移

Overexpression of Axin inhibits lymphoma cell invasion and metastasis in vitro by down-regulating β-catenin and MMP7/MMP9

目的探讨轴抑制因子(AXIN)通过β-catenin调控MMP7、MMP9对淋巴瘤细胞侵袭迁移能力的影响。方法用RT-PCR和Western blot法观察多株淋巴瘤细胞株里AXIN、β-catenin、MMP7、MMP9的表达情况;选取AXIN相对低表达的淋巴瘤细胞分组瞬时转染p CMV5-HA-Axin和pc DNA5-His-β-catenin质粒,采用RT-PCR和Western blot法观察其细胞中β-catenin、MMP7、MMP9 m RNA及蛋白表达变化;构建稳定高表达AXIN的淋巴瘤细胞后,分组瞬时转染AXIN-sh RNA和β-catenin-sh RNA后观察β-catenin、MMP7、MMP9 m RNA及蛋白变化;采用Transwell侵袭实验观察空白处理对照组、稳定高表达AXIN组、干扰AXIN的稳定高表达AXIN组细胞侵袭和迁移能力变化。结果多株淋巴瘤细胞株中AXIN与β-catenin、MMP7、MMP9表达呈负相关;选用AXIN相对低表达的人恶性B淋巴瘤细胞株Raji,过表达AXIN后发现AXIN升高后,β-catenin、MMP7、MMP9的蛋白表达降低,MMP7、MMP9、β-catenin m RNA未变化;当过表达β-catenin后发现MMP7、MMP9 m RNA和蛋白表达升高;另外,稳定高表达AXIN的细胞中干扰AXIN,β-catenin、MMP7、MMP9蛋白表达升高,MMP7、MMP9、β-catenin m RNA未变化;稳定高表达AXIN的细胞中干扰β-catenin,MMP7、MMP9表达降低;证实AXIN通过β-catenin调控MMP7、MMP9影响淋巴瘤细胞的侵袭和迁移。结论在淋巴瘤细胞中升高AXIN可引起β-catenin表达下降,进而MMP7、MMP9表达下降,抑制淋巴瘤细胞的侵袭和迁移。

Objective To investigate that the role of Axin in regulating the invasion and migration ability of lymphoma cells and explore the molecular mechanisms. Methods The expressions of Axin, β- catenin, MMP7, and MMP9 were detected in different lymphoma cell lines by RT- PCR and Western blotting. A lymphoma cell line with low Axin expressions was transiently transfected with p CMV5-HA-Axin and pc DNA5-His-β-catenin plasmid, and the expressions of β-catenin, MMP7,and MMP9 m RNA and protein were observed. A lymphoma cell model stably overexpressing Axin was transfected with AXINsh RNA and β-catenin-sh RNA, and the changes in β-catenin, MMP7, and MMP9 cexpressions were observed. The changes in the invasion and migration abilities of this cell model were assessed following Axin knockdown. Results In the lymphoma cell lines tested, the Axin expression showed a negative correlation with β- catenin, MMP7, and MMP9 expressions. In Raji cells with a low Axin expression, overexpression of Axin resulted in decreased expressions of β-catenin, MMP7, and MMP9 at the protein levels but not the m RNA levels, and overexpression of β- catenin obviously increased MMP7 and MMP9 m RNA and protein expressions. In the cells with stable Axin overexpression, Axin knockdown caused increased expressions of β-catenin,MMP7, and MMP9 at the protein levels but not the m RNA levels, while β-catenin knockdown caused lowered expressions of MMP7 and MMP9 and suppressed cell invasion and migration. Conclusion In lymphoma cells, Axin overexpression can decrease the expression of β-catenin, which in turn decreases the expressions of MMP7 and MMP9 to inhibit the cell invasion and migration.