COX-2 overexpression increases motility and invasion of breast cancer cells.
COX-2 overexpression increases motility and invasion of breast cancer cells.
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DOI：
10.3892/ijo.26.5.1393
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发表时间：
2005-05
影响因子：
5.2
通讯作者：
Balraj Singh;Jacob A. Berry;A. Shoher;Vijayalakshmi Ramakrishnan;A. Lucci
中科院分区：
文献类型：
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作者：
Balraj Singh;Jacob A. Berry;A. Shoher;Vijayalakshmi Ramakrishnan;A. Lucci
环加氧酶-2 (COX-2) 是一种参与前列腺素（包括 PGE(2)）生物合成的诱导酶，在包括乳腺癌在内的多种上皮恶性肿瘤中过度表达。我们测试了乳腺癌细胞中 COX-2 过度表达导致细胞运动和侵袭增加的假设。 COX-2 过量产生的细胞是通过用 pSG5-COX2 载体稳定转染几种人乳腺癌细胞而产生的。我们通过蛋白质印迹和免疫分析测定培养基中的 PGE(2) 证实了 COX-2 蛋白的过度表达。我们通过计算穿过 8 微米孔径 PET 膜的细胞数量来测量细胞运动性，并通过计算穿过模拟基底膜的基质胶涂层膜入侵的细胞数量来测量细胞侵袭性。 COX-2 转染的 MDA-231 细胞产生的 PGE2 是亲代细胞的 30-43 倍。 COX-2 过表达使细胞迁移增加约 2.2 倍，细胞通过 Matrigel 的侵袭增加约 5.1 倍。与溶剂相比，添加 50 microM NS-398（一种 COX-2 抑制剂）可将 MDA-231 细胞的 Matrigel 侵袭抑制 54%，证实了 COX-2 在细胞侵袭中的作用。众所周知，由于尿激酶原纤溶酶原激活剂（pro-uPA）表达增加，细胞骨架改变和基底膜降解可导致细胞迁移和侵袭的增加。为了研究我们观察到的 COX-2 增加细胞侵袭的机制，我们通过蛋白质印迹发现，COX-2 转染的 MDA-231 细胞中 pro-uPA 的水平显着高于未转染的 MDA-231 细胞（约 5 倍）。与我们在细胞培养中的观察结果类似，我们在乳腺癌骨转移小鼠模型中发现了 COX-2 活性增加与 uPA 相关的证据。在这项研究中，我们得出结论，COX-2 在人乳腺癌细胞中过度表达可增强细胞运动性和侵袭性，从而表明 COX-2 介导的转移机制。
Cyclooxygenase-2 (COX-2), an inducible enzyme involved in prostaglandin (including PGE(2)) biosynthesis, is overexpressed in several epithelial malignancies including breast cancer. We tested the hypothesis that COX-2 overexpression in breast cancer cells results in increased cell motility and invasion. COX-2 overproducing cells were generated by stable transfection of several human breast cancer cells with pSG5-COX2 vector. We confirmed the overexpression of COX-2 protein by western blotting, and by measuring PGE(2) in the medium with an immunoassay. We measured cell motility by counting the number of cells crossing an 8-micron pore size PET membrane, and cell invasion by counting the number of cells invading through a Matrigel-coated membrane that simulates basement membrane. COX-2 transfected MDA-231 cells produced 30-43-fold more PGE2 as compared to parental cells. COX-2 overexpression increased cell migration approximately 2.2-fold and cell invasion through Matrigel approximately 5.1-fold. Addition of 50 microM NS-398, a COX-2 inhibitor, inhibited Matrigel invasion of MDA-231 cells by 54% as compared to solvent confirming the role of COX-2 in cell invasion. It is known that an increase in cell migration and invasion can be brought about by cytoskeletal alterations and basement membrane degradation due to increased expression of pro-urokinase plasminogen activator (pro-uPA). To investigate the mechanism of our observed increase in cell invasion by COX-2, we found by western blotting that the level of pro-uPA was significantly higher (approximately 5-fold) in COX-2 transfected MDA-231 cells than untransfected MDA-231 cells. Similar to our observations in cell culture, we found evidence that increased COX-2 activity correlates with uPA in a mouse model of breast cancer metastasis to bone. In this study, we conclude that COX-2 overexpression in human breast cancer cells enhances cell motility and invasiveness thus suggesting a mechanism of COX-2 mediated metastasis.