Liu Li-Teh, Chang Hui-Chiu, Chiang Lien-Chai, Hung Wen-Chun
Graduate Institute of Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan.
Oncogene. 2002 Nov 28;21(54):8347-50. doi: 10.1038/sj.onc.1206017.
Nonsteroidal anti-inflammatory drugs (NSAIDs) are known to exert anti-angiogenic and anti-metastatic activity both in vitro and in vivo. Block of angiogenesis and metastasis by NSAIDs has been found to be mediated partly via suppression of matrix metalloproteinase (MMP) activity. However, the molecular mechanism of this inhibitory action has not been well defined. Recent works demonstrated that a membrane-anchored MMP inhibitor RECK may potently suppress MMP-2 and -9 activity to inhibit angiogenesis and metastasis in vitro and in vivo. In this study, we test the possibility that NSAIDs may up-regulate RECK to inhibit MMP activity. RT-PCR analyses showed that NS398 and aspirin up-regulated RECK mRNA level in CL-1 human lung cancer cells. Additionally, NSAIDs increased RECK protein level as detected by immunoblotting. Since RECK is a membrane-anchored glycoprotein, we also performed immunofluorescent staining to assess the expression of RECK on cell surface. Our results showed that fluorescent intensity of RECK was obviously increased after NSAID treatment. Moreover, induction of RECK by NSAIDs was associated with reduction of MMP-2 activity. We also found that NSAID-activated RECK expression might not be mediated via inhibition of cyclo-oxygenases (COXs) because addition of prostaglandin E(2) (PGE(2)) could not counteract the effect of NSAIDs and overexpression of COX-2 could not down-regulate RECK. Taken together, our results suggest that induction of RECK expression may be one of the mechanisms by which NSAIDs suppress MMP activity to block angiogenesis and metastasis.
已知非甾体抗炎药（NSAIDs）在体外和体内均具有抗血管生成和抗转移活性。已发现NSAIDs对血管生成和转移的阻断部分是通过抑制基质金属蛋白酶（MMP）活性介导的。然而，这种抑制作用的分子机制尚未完全明确。最近的研究表明，一种膜锚定的MMP抑制剂RECK可能在体外和体内有效抑制MMP-2和-9的活性，从而抑制血管生成和转移。在本研究中，我们测试了NSAIDs可能上调RECK以抑制MMP活性的可能性。RT-PCR分析表明，NS398和阿司匹林可上调CL-1人肺癌细胞中RECK的mRNA水平。此外，通过免疫印迹检测发现NSAIDs增加了RECK蛋白水平。由于RECK是一种膜锚定糖蛋白，我们还进行了免疫荧光染色以评估RECK在细胞表面的表达。我们的结果表明，NSAIDs处理后RECK的荧光强度明显增加。此外，NSAIDs诱导RECK与MMP-2活性降低有关。我们还发现，NSAIDs激活的RECK表达可能不是通过抑制环氧化酶（COXs）介导的，因为添加前列腺素E2（PGE2）不能抵消NSAIDs的作用，且COX-2的过表达不能下调RECK。综上所述，我们的结果表明，诱导RECK表达可能是NSAIDs抑制MMP活性以阻断血管生成和转移的机制之一。
