转化生长因子β1协同基质细胞衍生因子1通过抑制β连环素活性影响肝卵圆细胞增殖  

Transforming growth factor β1 cooperates with stromal cell derived factor 1 to affect the proliferation of hepatic oval cells via β-catenin inactivation

作　　者：胡荣林[1] 黄庆[1] 杨学伟[1] 彭和平[1] 杜军[2] 焦兴元[3] 

机构地区：[1]广州医学院第二附属医院肝胆外科,广东广州510260 [2]中山大学药学院微生物与生化制药实验室 [3]中山大学附属第一医院器官移植中心

出　　处：《中华外科杂志》2013年第5期442-446,共5页Chinese Journal of Surgery

基　　金：国家自然科学基金资助项目（81270531）;广东省科技计划资助项目（20098030801371）

摘　　要：目的探讨基质细胞衍生因子1（SDF-1）在肝卵圆细胞增殖过程中的效应、影响因素及作用机制。方法流式细胞术检测大鼠肝卯圆细胞株WB-F344细胞表面趋化性细胞受体因子4（CXCR4）的表达情况。Westernblot法检测细胞中β连环素蛋白磷酸化水平。激光共聚焦显微镜观察细胞内β连环素的分布情况。荧光定量PCR检测经典Wnt通路下游基因Ccndl、c-Myc的表达。将细胞分为对照组、SDF-l组、转化生长因子βl（TGF-β1）组、SDF-1＋TGF-β1组、SDF-1＋TGF-β1＋CXCR4抑制剂组，噻唑蓝法检测各组细胞增殖情况。结果WB-F344细胞中CXCR4的表达量很低，而TGF-β1可上调WB-F344细胞CXCR4的表达（CXCR4阳性率上升39．5％）。SDF-1结合于CXCR4后可促进肝卵圆细胞中β连环素磷酸化，抑制β连环素入核，下调下游基因Ccndl、c-Myc的表达。200μg／L的SDF-1单独作用72h后WB-F344细胞的增殖情况（0．5124-0．010）与对照组（0．513±0．008）相比差异无统计学意义（t=0．337，P〉0．05），5肌∥L的TGF-β1可轻度抑制其增殖（0．393±0．007，t=28．001，P〈0．05），而SDF-1＋TGF-β1组WB-F344细胞增殖能力较TGF-β1组进一步减弱（0．272±0．009，t=32．204，P〈0．05）。结论TGF-131可上调肝卵圆细胞中CXCR4的表达，协同SDF-1通过调控B连环素的功能状态，抑制肝卵圆细胞体外增殖。Objective To investigate the role of stromal cell derived factor 1 （SDF-1） on the proliferation of hepatic oval cells, and the influencing factors. Methods Flow cytometry was used to detect the expression of CXCR4 on the cell surface when WB-F344 cells were growing in the culture medium with and without transforming growth factor β1 （ TGF-β1 ） respectively. Western bolt was used to detect the expression of β-catenin and its phosphorylation level. The translocation of β-catenin was shown by confocal microscopy analysis. Q-RT-PCR was used in detecting the β-catenin downstream gene expression such as Ccndl and c-Myc. MTT was used to detect the proliferation of WB-F344 cells which were treated by SDF-1 ＋ TGF-β1 and those cells exposed to SDF-1 or TGF-β1 only, as well as of the negative control group. Results WB-F344 cells rarely express CXCR4 under conventional circumstance, but this receptor can be up-regulated when the culture medium contain a modest amount of TGF-β1 （ the rate of CXCR4 positive cell increased by 39. 5% ）. The bond of SDF-1 to CXCR4 results in the phosphorylation of β-catenin, and its inactivation. SDF-I alone didn＇t affect the proliferation of WB-F344 cells （0. 512 ± 0. 010 vs. O. 513 ± 0. 008, t =0. 337, P 〉 0. 05）, while TGF-β1 group show a slight decrease of cell population （0. 393 ＋ 0. 007,t =28.001, P 〈0. 05）. But when TGF-β1 combined with SDF-1, the proliferation of WB-F344 was more weakened than TGF-β1 group, and the difference was statistically significant （0. 272±O. 009, t =32. 204, P 〈 0. 05）. Conclusions TGF-β1 can up-regulate the expression of CXCR4 in hepatic oval cells, and then inhibit the proliferation of hepatic oval cells via inactivating β-catenin in vitro.

关 键 词：干细胞 转化生长因子Β1 受体 CXCR4 Β连环素 

分 类 号：R575[医药卫生—消化系统]