SAA蛋白与BCL-2、Caspase-3及NF-κB关系的研究

Research of the relationship of SAA protein among BCL-2,Caspase-3 and NF-κB

目的:探讨血清淀粉样蛋白A(SAA)的超表达和抑制表达对BCL-2、Caspase-3及NF-κB这3种信号分子蛋白表达的影响。方法:将课题组前期已构建成功的pc DNA3.1(+)-SAA超表达载体和p GPU6/GFP/Neo-SAA表达干扰载体采用脂质体法分别转染鼻咽癌CNE2细胞,建立SAA蛋白超表达的pc DNA3.1(+)-SAA-CNE2细胞系和干扰SAA蛋白表达的p GPU6/GFP/Neo-SAA-CNE2细胞系。pc DNA3.1(+)-SAACNE2细胞、CNE2细胞、p GPU6/GFP/Neo-SAA-CNE2细胞中SAA蛋白的表达量会逐渐减少,当SAA蛋白的表达量改变时,通过免疫印迹法检测BCL-2、Caspase-3及NF-κB在pc DNA3.1(+)-SAA-CNE2细胞、CNE2细胞、p GPU6/GFP/Neo-SAA-CNE2细胞中的表达。结果:SAA蛋白的表达在pc DNA3.1(+)-SAA-CNE2细胞系中明显增多(P<0.05),在p GPU6/GFP/Neo-SAA-CNE2细胞系中显著减少(P<0.05),由此可知,pc DNA3.1(+)-SAA超表达载体和p GPU6/GFP/Neo-SAA表达干扰载体成功转染CEN2细胞。免疫印迹检测结果示:随着SAA蛋白表达的增多,BCL-2的表达增多(P<0.05)、Caspase-3及NF-κB的表达减少(P<0.05)。结论:SAA蛋白在人鼻咽癌CNE2细胞中的表达与抑制凋亡的BCL-2蛋白表达有协同作用,对凋亡调节分子Caspase-3及NF-κB蛋白的表达有抑制作用,可推测SAA蛋白可能有促进肿瘤生长、转移的作用。

Objective： To investigate the effect of over expression and inhibition expression of SAA protein on protein expression of BCL-2,Caspase-3 and NF- κB these three signaling molecules. Methods： Transfect the pc DNA3. 1（ ＋）- SAA over expression vector and p GPU6 / GFP / Neo- SAA expression interference vector which previously successfully constructed by the research group to nasopharyngeal carcinoma CNE2 cells respectively with liposome. Constructing pc DNA3. 1（ ＋）- SAA- CNE2 over expression cells and p GPU6 / GFP / Neo- SAA- CNE2 interference cells of SAA protein. The expression of SAA protein was gradually reduce respectively in pc DNA3. 1（ ＋）-SAA-CNE2 over expression cells,CEN2 cells and p GPU6 /GFP/Neo-SAA-CNE2 interference cells.Inspecting the expression of BCL-2,Caspase-3 and NF-κB in pc DNA3. 1（ ＋）-SAA-CNE2 cells and p GPU6 /GFP / Neo-SAA-CNE2 cells by Western-blotting. Results： Expression of SAA protein in pc DNA3. 1（ ＋）-SAACNE2 cell lines significantly increased（ P〈0. 05）,expression of SAA protein in p GPU6 / GFP / Neo-SAA-CNE2 cell lines significantly decreased（ P〈0. 05）. The expression of SAA protein would decrease respectively in pc DNA3. 1（ ＋）-SAA-CNE2 over expression cells,CEN2 cells and p GPU6 / GFP / Neo-SAA-CNE2 interference cells,the difference was statistically significant. Western-blotting showed that with the increase expression of SAA protein,expression of BCL-2 increased（ P〈0. 05）,but expression of Caspase-3 and NF-κB decreased（ P〈0. 05）. Conclusion： For the expression of SAA protein in human nasopharyngeal carcinoma cells CNE2,there is a positive correlation with expression of BCL-2 which restraining of apoptosis,a negative correlation with expression of Caspase-3 and NF-κB which regulating apoptosis. We can make a speculation that SAA protein may have the effect of promoting tumor growth and metastasis.