RECK-mediated suppression of tumor cell invasion is regulated by glycosylation in human tumor cell lines
RECK-mediated suppression of tumor cell invasion is regulated by glycosylation in human tumor cell lines
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DOI：
10.1158/0008-5472.can-04-4446
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发表时间：
2005-08-15
期刊：
影响因子：
11.2
通讯作者：
Osada, H
中科院分区：
文献类型：
--
作者：
Simizu, S;Takagi, S;Osada, H
RECK是一种糖基磷脂酰肌醇（GPI）锚定的糖蛋白，负性调节基质金属蛋白酶（MMP），如MMP-9，并抑制肿瘤侵袭和转移。预测的人RECK的氨基酸序列包括5个假定的N-糖基化位点;然而，糖基化RECK的精确生物化学作用仍然未知。在这项研究中，我们研究了人类肿瘤细胞系中糖基化与RECK功能之间的联系。RECK蛋白被糖基化。在HT 1080细胞中，Asn（86）、Asn（200）、Asn（297）和Asn（352）残基处，但在Asn（39）残基处不存在。虽然这些天冬酰胺位点的糖基化在RECK作为GPI锚定蛋白的细胞表面定位中不起作用，但RECK Asn（297）残基的糖基化参与了MMP-9分泌的抑制，Asn（352）残基是抑制MMP-2活化所必需的。此外，通过抑制RECK的Asn（86）、Asn（297）和Asn（352）残基的糖基化，RECK抑制的肿瘤细胞侵袭被逆转。因此，这些发现表明糖基化通过多种机制介导RECK抑制肿瘤细胞侵袭，例如抑制MMP-9分泌和抑制MMP-2活化。
RECK, a glycosylphosphatidylinositol (GPI)-anchored glycoprotein, negatively regulates matrix metalloproteinases (MMP), such as MMP-9, and inhibits tumor invasion and metastasis. The predicted amino acid sequence of human RECK includes five putative N-glycosylation sites; however, the precise biochemical role of glycosylated RECK remains unknown. In this study, we examined the link between glycosylation and the function of PECK in human tumor cell lines. RECK protein was glycosylated. at Asn(86), Asn(200), Asn(297), and Asn(352) residues but not at the Asn(39) residue in HT1080 cells. Although the glycosylation of these asparagine sites did not play a role in the cell surface localization of RECK as a GPI-anchored protein, the glycosylation of RECK Asn(297) residue was involved in the suppression of MMP-9 secretion and Asn(352) residue was necessary to inhibit MMP-2 activation. Moreover, RECK-suppressed tumor cell invasion was reversed by inhibiting glycosylation at Asn(86), Asn(297), and Asn(352) residues of RECK Thus, these findings indicate that glycosylation mediates RECK suppression of tumor cell invasion by multiple mechanisms such as suppressing MMP-9 secretion and inhibiting MMP-2 activation.