Objective To investigate the mechanisms of upregulation of matrix metalloprotein-ases(MMPs)and promotion of lung cancer cell metastasis by transcription factor brachyury. Methods Lung cancer cell lines with over-expression and down-expression of brachyury were constructed to observe the effect of brachyury on invasion ability of non-small cell lung cancer (NSCLC)cells.The expression of 23 MMPs was detected by RT-PCR and real-time PCR.The re-lationship between brachyury and MMPs was analyzed by immunohistochemistry in primary NSCLC specimens.The potential brachyury-binding sites in promoters of MMPs were determined by CHIP-PCR.Results Brachyury promoted the invasion of lung cancer cells.The expression of MMP12 and MMP24 was increased by 323%(P=0.02)and 183%(P=0.40)in cells with brachyury over-expression,respectively.However,the expression of MMP7,MMP9,MMP10, MMP12 and MMP19 was decreased by 34%(P=0.09),43%(P=0.08),56%(P=0.07),77%(P=0.002)and 23%(P=0.04)in cells with brachyury down-expression,respectively.Immuno-histochemistry confirmed a remarkable consistency in the expression of brachyury and MMPs. CHIP-PCR showed positive amplification of MMP12 promoter sequence(-266/-1443 bp).Conclu-sion Multiple MMPs,especially MMP12,are correlated with the expression of transcription fac-tor brachyury.The correlation may be one of mechanisms of brachyury promoting metastasis me-tastasis.%目的 探究转录因子Brachyury上调基质金属蛋白酶(MMPs)与促进肺癌细胞转移的机制.方法 建立Brachyury过表达和低表达的肺癌稳转细胞株,分析Brachyury转录因子对NSCLC细胞侵袭能力的影响;通过RT-PCR和real-time PCR技术比较23个MMPs的表达差异;原发性NSCLC组织标本免疫组织化学验证Brachyury与MMPs表达的关系.CHIP-PCR实验检测Brachyury对MMPs成员启动子是否存在调控位点.结果Brachyury转录因子能显著促进肺癌细胞的侵袭能力;Brachyury高表达的稳转细胞内MMP12、MMP24表达显著增加323%(P=0.02)、183%(P=0.40).Brachyury低表达的稳转细胞内MMP7、MMP9、MMP10、MMP12和MMP19显著降低34%(P=0.09)、43%(P=0.08)、56%(P=0.07)、77%(P=0.002)和23%(P=0.04);且免疫组织化学进一步验证了Brachyury与MMPs的表达具有显著一致性.CHIP-PCR结果显示MMP12启动子区域(转录起始位点上游5′-266/-1443 bp 3′)存在PCR显著扩增.结论 多个基质金属蛋白酶的表达与转录因子Brachyury表达相关,MMP12 可能与Brachyury的作用更加明显,这可能是 Brachyury能促进 NSCLC细胞转移的机制之一.
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