COX-2表达与乳腺癌EMT发生关系的研究

The relationship between expression of COX-2 and EMT in breast cancer

目的:为明确COX-2表达是否可以影响乳腺癌细胞上皮间质转化(EMT)变化,培养高表达的COX-2和EMT改变的乳腺癌MDA-MB-231细胞,用不同浓度的塞来昔布和小干扰RNA分别来抑制COX-2功能和表达,观测细胞EMT的变化和Snail的表达。方法:培养乳腺癌MDA-MB-231细胞,构建干扰COX-2 siRNA载体,将干扰载体转染MDAMB-231细胞,应用免疫荧光染色检测E-Cadherin、viminten和COX-2的表达,RT-PCR检测Western Blot检测Snail、COX-2的表达。检测培养液PGE2的水平。结果:小干扰RNA与塞来昔布治疗组相比E-Cadherin表达增加明显,viminten、Snail表达降低更显著,小干扰RNA处理乳腺癌MDA-MB-231细胞72 h后与塞来昔布处理的相比获得更多的上皮特征和更少的间质结构的特征。COX-2 mRNA在60μmol/L的塞来昔布处理组和RNAi处理组COX-2 mRNA的相对表达分别为0.97和0.22,塞来昔布不能抑制COX-2 mRNA表达。干扰组与塞来昔布组相比,细胞培养液中PGE2的浓度没有显著差异。结论:①COX-2的抑制可通过PGE2的下调调控乳腺癌EMT。②COX-2通过非PGE2依赖途径调节Snail的表达进而调控EMT的发生。

Objective： In order to study whether the expression of COX -2 could influence the EMT condition of breast cancer cell, the high COX- 2 expression and EMT condition human breast cancer MDA -MB -231 cells were cultured, and various concentration of celeeoxib and small interfering RNA were used to inhibit the function and the expression of COX - 2 respectively. Methods ： Human breast cancer MDA- MB -231 cells were cultured, adenovirus siRNA was designed and infected, the expressions of E- Cadherin, viminten and COX - 2 were detected by Fluorescent Immunohistochemical Staining. Snail was detected by RT - PCR. The expression of COX - 2 was detec- ted by Western Blot. Results： E- Cadherin expression increased significantly inRNAi group than that in celecoxib treatment group , while viminten and Snail expression decreased more significantly. Compared to treatment with celeeoxib, small interfering RNA treatment of breast cancer MDA -MB - 231 cells after 72 h had more features and less epithelial stromal structural characteristics. The relative COX -2 mRNA expression in 60 μmol/L of eelecoxib treatment group and RNAi treatment group was 0. 97 and 0. 22, respectively, celecoxib couldn＇ t in- hibit COX - 2 mRNA expression. PGE2 concentration in cell cuhure medium was not significantly different between the two groups. Conclu- sion ： ①COX - 2 - inhibition mediated reverse of EMT was only partly dependent on PGE2 cascade. ②COX - 2 may modulate EMT of breast cancer by regulating Snail independent of PGE2.