多形性腺瘤中BMP的表达及作用机制分析

目的：检测多形性腺瘤中ＢＭＰ蛋白的表达及ＭＢＰ２ ｍＲＮＡ的扩增情况,以探讨多形性腺瘤的病理发生机制。方法：应用ＢＭＰ单克隆抗体检测ＢＭＰ在多形性腺瘤中的表达,并进一步应用ＭＢＰ２的特异性引物和ＲＴ－ＰＣＲ的方法,扩增６例多形性腺瘤组织中ＲＮＡ。结果：６例多形性腺瘤组织中可以检测到ＢＭＰ蛋白的扩增,其中５例有ＢＭＰ２ ｍＲＮＡ扩增。结论：ＢＭＰ可能参与了多形性腺瘤的病理机制,ＢＭＰ的存在可能是上皮

The Expression and Mechanism Study of BMP in Pleomorphic Adenoma

OBJECTIVE: One important pathological character of pleomorphic adenomas is that there is chorndriod component in the epithelial tumors. It is well known that bone morphogenetic protein (BMPs) plays important roles in the morphogenesis of hard tissue by inducing mesenchymal cells to differentiate into osteoblasts and chondroblasts in vivo. So we examined the expression of BMP and BMP2 mRNA in pleomorphic adenomas to study the pathological mechanism of chorndriod tissue formation. METHODS: Using ABC immunohistochemistry method, 6 specimens of pleomorphic adenomas were examined with BMP antibody. Reverse transcriptase-polymerase chain reaction (RT-PCR) methods were developed for detecting BMP2 mRNA expression with special primers used to amplify the BMP2 cDNA mature domain fragment. The total RNA was extracted from frozen 6 specimens of pleomorphic adenoma and then reversed to cDNA by reverse transcription using AMV reverse transcriptase. PCR conditions were 94 degrees C for 20 seconds, 60 degrees C for 30 seconds, and 72 degrees C for 1 minute, 40 cycles, followed by extension for 30 minute at 72 degrees C. The reaction products were analyzed by electrophoresis. RESULTS: BMP expression could be found in all of the specimens of pleomorphic adenoma examined by immunohistochemistry method. BMP2 RT-PCR product was detected in only 5 specimens that showed BMP2 mRNA existed in 5 specimens. CONCLUSION: These results may be helpful to study the mechanism of pleomorphic adenoma. It is speculated that BMP secreted by tumor cells may play important roles in origin of osteoid tissue in pleomorphic adenoma by inducing neoplastic myoepithelial cells to differentiate to chondrocytes.