HSulf-1 modulates FGF2- and hypoxia-mediated migration and invasion of breast cancer cells.
HSulf-1 modulates FGF2- and hypoxia-mediated migration and invasion of breast cancer cells.
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DOI：
10.1158/0008-5472.can-10-3059
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发表时间：
2011-03-15
期刊：
影响因子：
11.2
通讯作者：
Shridhar V
中科院分区：
文献类型：
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作者：
Khurana A;Liu P;Mellone P;Lorenzon L;Vincenzi B;Datta K;Yang B;Linhardt RJ;Lingle W;Chien J;Baldi A;Shridhar V
HSulf-1调节肝素结合生长因子信号传导关键的硫酸乙酰肝素蛋白聚糖的硫酸化状态。在本研究中，我们证明了HSulf-1在乳腺癌细胞系中在缺氧条件下转录失调。在RNA和蛋白水平上，HIF-1α的敲低挽救了缺氧引起的HSulf-1下调。用HIF-1α和HIF-2α抗体进行的染色质免疫沉淀证实了HIF-α蛋白被募集到天然HSulf-1启动子上的两个功能性缺氧应答元件。乳腺癌细胞中的HSulf-1缺失导致bFGF 2信号的增加和持续，促进细胞在缺氧条件下的迁移和侵袭。此外，HSulf-1沉默乳腺癌细胞中的FGFR 2缺失减弱了缺氧介导的细胞侵袭。对53例浸润性导管癌及其自身转移灶的免疫组化分析显示，HSulf-1与CAIX在原发性肿瘤（p=>0.0198）和转移灶（p=>0.0067）中的表达分别呈负相关（χ2检验）。最后，通过RNA原位杂交检测乳腺肿瘤中HSulf-1的表达水平表明，HSulf-1的高表达与无病生存期和总生存期的增加相关（分别为p= >0.03和p=>0.0001）。总的来说，这些结果揭示了缺氧微环境下HSulf-1的丢失与生长因子信号传导、细胞迁移和侵袭增加之间的重要联系。
HSulf-1 modulates the sulfation states of heparan sulfate proteoglycans critical for heparin binding growth factor signaling. In the present study, we demonstrate that HSulf-1 is transcriptionally deregulated under hypoxia in breast cancer cell lines. Knockdown of HIF-1α rescued HSulf-1 downregulation imposed by hypoxia, both at the RNA and protein levels. Chromatin immunoprecipitation with HIF-1α and HIF-2α antibodies confirmed recruitment of HIF-α proteins to the two functional hypoxia responsive elements on the native HSulf-1 promoter. HSulf-1 depletion in breast cancer cells resulted in an increased and sustained bFGF2 signaling, promoted cell migration and invasion under hypoxic conditions. Additionally, FGFR2 depletion in HSulf-1 silenced breast cancer cells attenuated hypoxia mediated cell invasion. Immunohistochemical analysis of 53 invasive ductal carcinomas and its autologous metastatic lesions revealed an inverse correlation of expression of HSulf-1 to CAIX in both the primary tumors (p=>0.0198) and in metastatic lesions (p=>0.0067) respectively, by χ2 test. Finally, HSulf-1 expression levels in breast tumors by RNA in situ hybridization showed that high HSulf-1 expression is associated with increased disease-free and overall survival (p= >0.03 and p=>0.0001 respectively). Collectively, these results reveal an important link between loss of HSulf-1 under hypoxic microenvironment and increased growth factor signaling, cell migration and invasion.