乳腺癌中PKCζ、MMP-2、MMP-9的表达及相关性

Expression and correlation of PKCζ,MMP-2 and MMP-9 in breast cancer

目的探讨乳腺癌中蛋白激酶Cζ(protein kinase Cζ,PKCζ)、基质金属蛋白酶-2(matrix metalloproteinase-2,MMP-2)、基质金属蛋白酶-9(matrix metalloproteinase-9,MMP-9)的表达及三者与其侵袭、转移的关系。方法应用免疫组化PV 9000两步法检测PKCζ、MMP-2、MMP-9在100例乳腺癌组织及对应癌旁正常乳腺组织中的表达,并分析三者表达的相关性。应用RNAi技术将合成的PKCζ-siRNA转染入乳腺癌细胞株MDA-MB-231中,即siPKCζ/MDA-MB-231细胞组,以转染空载质粒的scr/MDA-MB-231的细胞组作为对照组,应用Transwell侵袭实验检测细胞的体外侵袭能力。利用Western blot法检测转染细胞中PKCζ蛋白的表达。酶联免疫吸附实验(enzyme-linked immunosorbent assay,ELISA)检测培养基中MMP-2、MMP-9的含量。结果PKCζ、MMP-2、MMP-9在乳腺浸润性导管癌中的阳性率分别为62.5%、37.5%、32.5%,明显高于乳腺导管内癌和癌旁正常乳腺组织(P均<0.05)。PKCζ蛋白表达与淋巴结转移、远处转移有关(P均<0.01),与患者年龄、肿瘤大小、临床分期、ER、PR等无关(P均>0.05);转染siRNA的siPKCζ/MDA-MB-231细胞组与scr/MDA-MB-231组相比,体外侵袭能力以及PKCζ蛋白的表达水平明显下降(P均<0.05),培养基中MMP-2、MMP-9蛋白表达量亦明显下降(P均<0.05)。结论 PKCζ通过影响乳腺癌细胞中MMP-2、MMP-9的分泌来促进乳腺癌的侵袭、转移。

Purpose To investigate the expressions of PKCζ,MMP-2,and MMP-9 in breast cancer and the relationship with the invasion and metastasis of breast cancer. Methods The expression of PKCζ,MMP-2 and MMP-9 in 100 cases with breast cancer was assessed with immunohistochemistry PV 9000 method. PKCζ-siRNA was transfected into MDA-MB-231 cell lines,called siPKCζ /MDAMB-231. While siRNA construct containing a scrambled sequence was transfected into MDA-MB-231 cells to generate control cells,which were designated as Scr /MDA231 cells. Western blotting was used to measure the expression of PKCζ in transfected cells,and the Transwell invasion assay was used to detect the invasion ability in vitro. The content of MMP-2,MMP-9 were measured by ELISA.Results The expression rates of PKCζ,MMP-2 and MMP-9 in breast cancer tissues were 62. 5%,37. 5% and 32. 5%,and there were significant differences among them（ P〈0. 05）. The expression of PKCζ was much higher than those in the normal breast tissues nearby. The expression of PKC protein was assoiated with lymph node metastasis,distant metastasis（ P〈0. 01）,but was not correlated with other clinicopathologic parameters,such as age,tumor size,histological type,ER,PR,and so on（ P〈0. 05）. The expression of PKCζ,MMP-2 and MMP-9 were lower in siPKCζ / MDA-MB-231 group than those in scr / MDA-MB-231 group,and the in vitro invasion ability was significantly decreased（ P〈0. 05）. Conclusions PKCζ can promote the invasion and metastasis of breast cancer,and correlated with the expression of MMP-2,MMP-9（ P〈0. 05）.