双歧杆菌完整肽聚糖对结肠癌细胞株SW480上皮-间质转化的调控作用研究

The regulation of Bifidobacterium whole peptidoglycan on epithelial-mesenchymal transition of colon cancer cell line SW480

目的研究双歧杆菌完整肽聚糖(whole peptidoglycan,WPG)对结肠癌细胞株SW480上皮-间质转化(epithelial mesenchymal transition,EMT)、侵袭和迁移能力的调控作用,阐明WPG抑制结肠癌细胞EMT从而影响肿瘤转移的分子机制。方法常规培养结肠癌细胞株SW480,分为NC组(阴性对照组)、EMT组(TGF-β1诱导EMT组)、EMT+WPG组、WPG组。给予WPG(116μg/ml)孵育48 h后,western-blot法检测EMT相关标志蛋白E-cadherin、Vimentin及转移相关蛋白MMP-2、MMP-9的表达,transwell检测细胞的侵袭及转移能力。结果TGF-β1诱导SW480细胞中EMT发生。与NC组相比,EMT组E-cadherin、MMP-2、MMP-9表达升高(P=0.0048、0.0026、0.0004),而Vimentin表达降低(P=0.0007),且增加了SW480细胞的侵袭(P=0.0013)及迁移数量(P<0.01);经WPG处理后(EMT+WPG组)E-cadherin、MMP-2、MMP-9表达降低(P=0.013、0.0315、0.0009),而Vimentin表达升高(P=0.0001),且细胞侵袭(P=0.0121)及迁移数量减少(P<0.01)。单纯给予WPG对SW480细胞中E-cadherin、Vimentin、MMP-2、MMP-9表达及对细胞侵袭及迁移无影响(P=0.518、0.238、0.281、0.3153)。结论双歧杆菌完整肽聚糖能抑制结肠癌细胞株SW480的EMT进程,降低结肠癌细胞的侵袭及转移能力。

Objective To investigate decipher the regulation of Bifidobacterium intact whole peptidoglycan(WPG)on epithelial-mesenchymal transition(EMT),invasion and migration of colorectal carcinoma cell line SW480(colorectal carcinoma cell line),and to elucidate the molecular mechanism of WPG in inhibiting EMT and affecting tumor metastasis of colon cancer cell line.Methods SW480 cells waswere cultured and divided into 4 experimental groups:NC group(negative control group),EMT group(TGF-β1 induced EMT group),EMT+WPG group and WPG alone group.After 48 hours fter of WPG(116 ug/ml)incubation,the expression of E-cadherin,Vimentin,MMP-2 and MMP-9 were detected by by western-blot,and the invasion and metastasis ability of cells were detected by transwell.Results Compared with NC group,the expressions of E-cadherin,MMP-2 and MMP-9 in EMT group was significantly increased(P=0.0048,0.0026,0.0004),while the expression of Vimentinwas decreased(P=0.0007),and the numbers of invasion and migration cells of SW480 were increased(P=0.0013,P<0.01).After WPG treatment,the expressions of E-cadherin,MMP-2 and MMP-9 were decreased(P=0.013,0.0315,0.0009),while the expression of Vimentin was increased(P=0.0001),and the numbers of cell invasion and migration wereas significantly decreased(P=0.0121,P<0.01).WPG treatment alone didn′t affect the expression of E-cadherin,Vimentin,MMP-2 and MMP-9 in SW480 cells(P=0.518,0.238,0.281,0.3153).Conclusions Bifidobacterium intact peptidoglycan WPG can inhibit the EMT process of SW480 cell and reduce the invasion and metastasis ability of colon cancer cells,and slow the development of tumor.