3,3’-二吲哚甲烷抑制STAT3通路对人卵巢癌细胞侵袭和迁移的影响

DIM suppresses the invasion and migration of human ovarian cancer cells through inhibiting STAT3 signal pathway

目的 :观察3,3’-二吲哚甲烷(3,3’-diindolymethane,DIM)对人卵巢癌A2780细胞侵袭和迁移能力的影响,并探讨信号转导和转录激活因子3(signal transducer and activator of transcription 3,STAT3)信号通路在DIM抑制卵巢癌细胞侵袭和迁移中的作用。方法 :以人卵巢癌A2780细胞为研究对象,用不同浓度的DIM处理后,分别采用细胞黏附实验、划痕实验和Transwell小室侵袭实验检测DIM对卵巢癌细胞黏附、迁移和侵袭能力的影响;激光共聚焦显微镜下观察DIM对A2780细胞中血管内皮生长因子(vascular endothelial growth factor,VEGF)和基质金属蛋白酶-2(matrix metalloproteinase-2,MMP-2)表达的影响;蛋白质印迹法检测DIM作用对STAT3及磷酸化STAT3(phospho-STAT3,p-STAT3)、VEGF和MMP-2表达水平的影响。结果:DIM处理后,细胞的黏附能力受到明显抑制,并呈浓度依赖性;划痕实验表明,DIM处理后细胞的迁移能力受到明显抑制,其划痕愈合率明显降低,抑制率呈时间-浓度依赖性(P<0.05);Transwell小室检测显示,对照组中穿过基质膜的细胞数为(537.33±53.15)个/视野,与DIM(50和100μmol/L)处理组的(326.00±20.15)和(59.33±13.32)个/视野相比,发生侵袭的细胞数显著减少(P<0.01);蛋白质印迹法检测结果显示,STAT3总蛋白的表达水平无明显改变,但p-STAT3蛋白的表达水平下调,并伴有VEGF及MMP-2表达的同步下调,差异均有统计学意义(P均<0.05);激光共聚焦显微镜下观察发现,DIM可下调A2780细胞中VEGF和MMP-2的表达水平。结论:DIM可以通过抑制STAT3的磷酸化,降低VEGF和MMP-2蛋白的表达水平,从而抑制卵巢癌细胞株A2780的侵袭和迁移能力。

Objective：To investigate the effects of 3,3’-diindolymethane（DIM） on the migration and invasion abilities of human ovarian cancer A2780 cells,and to explore the role of signal transducer and activator of transcription 3（STAT3） pathway in the possible mechanism.Methods：The human ovarian cancer A2780 cells were treated with different concentrations of DIM.The adhesion,migration and invasion abilities of A2780 cells were determined by adhesion assay,wound healing assay,and Transwell chamber invasion assay,respectively.The expressions of vascular endothelial growth factor（VEGF） and matrix metalloproteinase-2（MMP-2） in A2780 cells were observed under a laser scanning confocal microscope.The expression levels of STAT3,phospho-STAT3（p-STAT3）,VEGF and MMP-2 proteins were detected by Western blotting.Results：The adhesion ability of A2780 cells treated with DIM was inhibited in a dose-dependent manner.Wound healing assay showed that the rate of wound closure was signifi cantly reduced in DIM-treated A2780 cells in a time-and dose-dependent manner（P 〈 0.05）.The invasion assay showed that the numbers of A2780 cells treated with 50 and 100 μmol/L DIM invading through the chamber were both lower than that of the control cells [（326.00±20.15）/fi eld and（59.33±13.32）/fi eld vs（537.33±53.15）/fi eld,both P 〈 0.01].Western blotting analysis demonstrated that the expressions of total STAT3 proteins had no signifi cant change,but the expression levels of p-STAT3,VEGF and MMP-2 were down-regulated in A2780 cells treated with DIM（all P 〈 0.05）.Under the laser scanning confocal microscope,the down-regulation of the expression levels of VEGF and MMP-2 in A2780 cells indued by DIM was observed.Conclusion：DIM can inhibit the invasion and migration abilities of ovarian cancer cells through down-regulation of p-STAT3,VEGF and MMP-2 proteins.