中文摘要：

探讨BMP9对人乳腺癌MDA-MB-231细胞骨转移能力的影响及其可能的机制。扩增高滴度的BMP9表达腺病毒,感染MDA-MB-231细胞,制备表达BMP9的重组MDA-MB-231/BMP9细胞,以此作为实验组;同时以含GFP的空载腺病毒感染该细胞为MDA-MB-231/GFP,联合MDA-MB-231共同作为对照组;RT-PCR及Western blot检测重组MDA-MB-231/BMP9细胞中BMP9以及磷酸化Smad1（PSmad1）的表达;定量PCR及Western blot检测三组细胞中CTGFmRNA和蛋白水平的表达情况,最后结合X片运用免疫组织化学染色的方法检测三组标本中CTGF的表达。结果发现重组MDA-MB-231/BMP9细胞中存在BMP9的表达;与对照组细胞相比,MDA-MB-231/BMP9细胞中存在PSmad1的活化增强及CTGF的表达下调;X片发现实验组裸鼠胫骨溶骨性缺损减少;瘤体组织免疫组化发现实验组CTGF表达下调。所以BMP9可以在体内抑制乳腺癌MDA-MB-231细胞的骨转移并且这种抑制作用有可能是通过下调CTGF来实现的。

英文摘要：

The purpose is to investigate the effects and possible mechanisms on BMP9 inhibiting the bone metastasis of human breast cancer MDA-MB-231 cells.High titer adenovirus vector expressing BMP9 was used to infect MDA-MB-231 cells.Experimental group is MDA-MB-231/BMP9 cells,control groups are both MDA-MB-231/GFP cells and MDA-MB-231 cells.RT-PCR and Western blot were used to detect the expression of BMP9 and PSmad1 in recombinant MDA-MB-231/BMP9 cells;Q-PCR and Western blot were used to detect the expression of CTGF in three groups cells;At last,X Light and Immunohistochemistry were used separately to detect the osteolytic lesions and the expression of CTGF in three groups cells.BMP9 was expressed in recombinant MDA-MB-231/BMP9 cells;the recombinant MDA-MB-231/BMP9 cells exhibited higher level of phosphorylated Smad1 and lower level of CTGF than the MDA-MB-231/GFP cells and MDA-MB-231 cells,but total Smad1 protein was similar in the three groups.In comparison with the control groups,the osteolytic lesions observed were significantly reduced in MDA-MB-231/BMP9 group;The removed tumor samples were detected by immunohistochemistry,MDA-MB-231/BMP9 samples analysed showed less CTGF staining than the control samples.Taken together,BMP9 can inhibit the bone metastasis of breast cancer cells MDA-MB-231 in vivo and the downregulation of CTGF is the possible mechanism.