MMP-2、MMP-9在高、低转移潜能乳腺癌细胞中的表达变化

Expressions of matrix metalloprotainese-2 and metalloprotainese-9 in human breast cancer cell line MDA-MB-435s with high-and low-metastatic potentiality

目的筛选高、低转移潜能的乳腺癌细胞亚系,研究基质金属蛋白酶-2(matrix metalloprotainese,MMP-2)、MMP-9在高、低转移潜能乳腺癌细胞的表达差异及其意义。方法利用人乳腺癌细胞系MDA-MB-435s细胞在Transwell小室上连续穿透人工基质膜获得高、低转移潜能乳腺癌细胞株。用细胞侵袭实验、免疫组化、Western blot方法,测定2株细胞的侵袭能力和MMP-2和MMP-9的表达情况。结果细胞侵袭实验结果显示,侵袭实验20 h时,高转移潜能乳腺癌细胞的侵袭能力[(61.40±7.08)个/视野]强于低转移潜能乳腺癌细胞[(25.34±4.87)个/视野,P<0.05]。免疫组化和图像分析结果显示,MMP-2和MMP-9在高转移潜能乳腺癌细胞中的表达水平[分别为(0.24±0.04)、(0.23±0.05)]高于低转移潜能乳腺癌细胞[分别为(0.16±0.02)、(0.13±0.03),P<0.05]。将免疫组化结果和细胞侵袭实验结果进行Pearson相关分析,结果表明MMP-2、MMP-9的表达水平与穿透Transwell小室的数量呈正相关(r=0.957、r=0.964,P<0.05)。Western blot检测结果也显示,高转移潜能乳腺癌细胞的MMP-2和MMP-9的表达[分别为(0.59±0.14)、(0.67±0.17)]明显高于低转移潜能乳腺癌细胞[分别为(0.31±0.07)、(0.35±0.06),P<0.05]。结论利用细胞穿透人工基底膜能力的差异能够筛选出高、低转移潜能的乳腺癌细胞;MMP-2、MMP-9的蛋白表达与乳腺肿瘤的侵袭能力关系密切。

Objective To establish the subclones of MDA-MB-435s human breast cancer cells with high and low potentiality of metastasis,and then investigate the differences of the expressions of matrix metalloprotainese-2 and-9（MMP-2 and MMP-9） between these 2 subclones.Methods Transwell invasion assay was used to screen the subclones of MDA-MB-435s cells with high-and low-metastatic potentiality.The expressions of MMP-2 and MMP-9 were examined with immunohistochemical staining and Western blot analysis,and cell invasion ability was evaluated Transwell invasion assay.Results Transwell invasion assay showed the ivasion ability of breast cancer cells was higher in the cells with high-metastatic potentiality than those with low-metastatic potentiality,with significant difference（P0.05）.Immunohistochemistry showed that the expression levels of MMP-2 and MMP-9 were significantly higher in cells with high metastatic potentiality（0.24±0.04 and 0.23±0.05 respectively） than that in cells with low metastatic potentiality（0.16±0.02 and 0.13±0.03 respectively,P0.05）.These results were confirmed by Western blot assay.A positive correlation was found between the expression levels of MMP-2/9 and the invasion potentiality of MDA-MB-435s（r=0.957,0.964,P0.05）.Conclusion The subclones of human breast cancer cells with high-and low-metastatic potentiality can be screen with Transwell invasion assay.Tumour cells to penetrate a matrigel barrier in vitro is closely related with the expression levels of MMP-2 and MMP-9 in human breast cancer cells.