Regulation of HIF-1 alpha by the proprotein convertases furin and PC7 in human squamous carcinoma cells.
Regulation of HIF-1 alpha by the proprotein convertases furin and PC7 in human squamous carcinoma cells.
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DOI：
10.1002/mc.22131
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发表时间：
2015-09
影响因子：
4.6
通讯作者：
Klein-Szanto, Andres J.
中科院分区：
文献类型：
--
作者：
Fu, Jian;Zhang, Jirong;Gong, Yulan;Testa, Courtney Lyons;Klein-Szanto, Andres J.
前蛋白转化酶（Proprotein convertases，PC）是一个丝氨酸蛋白酶家族，主要参与肿瘤相关底物如生长因子、生长因子受体、细胞粘附分子、金属蛋白酶等的加工。Furin（PCSK 3）是HIF-1α反式激活调控的众多靶基因之一，缺氧可通过HIF-1α触发PCSK 3分布到细胞内体和细胞表面。将敲低PC的siRNA单独或与不同药物处理组合转染到细胞中。蛋白质和RNA表达水平分别通过Western blotting或RT-PCR分析。PC 7（PCSK 7）和furin siRNA在常氧条件下上调HIF-1α蛋白至与氯化钴处理所获得的水平相似的水平，最终导致两种人头颈部鳞状细胞癌细胞系中VEGF-A合成的激活。在siRNA处理下HIF-1α mRNA表达水平不变，PC siRNA和氯化钴或26 S核糖体抑制剂MG-132对HIF-1α的诱导增加，表明转录后PC介导的调节。放线菌酮追踪结果显示PC 7/furin siRNA调控发生在HIF-1α翻译水平。一种特异性IGF-1 R信号抑制剂能够减弱PC siRNA对HIF-1α的诱导，表明IGF-1 R通路参与其中。因此，数据表明PC调节HIF-1α。Furin和PC 7 siRNA通过增加HIF-1α蛋白的翻译来诱导HIF-1α蛋白，导致VEGF-A的上调。这一发现可能提供洞察复杂的PC功能，似乎是独立于其基板处理活动。
Proprotein convertases (PC), a family of serine proteases, process cancer-related substrates such as growth factors, growth factor receptors, cell adhesion molecules, metalloproteinases, etc. HIF-1α is a major transcription factor involved in tumorigenesis by sensing intratumoral hypoxia. Furin (PCSK3) is one of the numerous target genes regulated by HIF-1α transactivation and its distribution into endosomal compartments and onto the cell surface can be triggered by hypoxia via HIF-1α. siRNAs to knockdown PCs were transfected into cells alone or in combination with different drug treatments. Protein and RNA expression levels were analyzed by Western blotting or RT-PCR respectively. PC7 (PCSK7) and furin siRNAs upregulated HIF-1α protein under normoxic condition to a level similar to that obtained by cobalt chloride treatment, eventually leading to activation of VEGF-A synthesis in two human head and neck squamous cell carcinoma cell lines. The unchanged levels of HIF-1α mRNA expression under siRNA treatment and the additive HIF-1α induction of PC siRNAs and either cobalt chloride or the 26S ribosome inhibitor, MG-132, suggested a post-transcriptional PC-mediated regulation. Furthermore, cycloheximide chase showed that PC7/furin siRNA regulation occurred at the level of HIF-1α translation. A specific IGF-1R signaling inhibitor was able to attenuate the PC siRNA induction of HIF-1α, suggesting the involvement of the IGF-1R pathway. Thus, the data show that PCs regulate HIF-1α. Furin and PC7 siRNAs induced HIF-1α protein by increasing its translation, resulting in upregulation of VEGF-A. This finding may provide insight into intricate PC functions that seem to be independent from their substrate-processing activity.
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影响因子：
11.2
作者：
de Cicco, RL;Bassi, DE;Klein-Szanto, AJP
通讯作者：
Klein-Szanto, AJP
影响因子：
11.2
作者：
Bassi, DE;De Cicco, RL;Klein-Szanto, AJP
通讯作者：
Klein-Szanto, AJP
影响因子：
4.8
作者：
Khatib, AM;Siegfried, G;Seidah, NG
通讯作者：
Seidah, NG
影响因子：
4.7
作者：
Mahloogi, H;Bassi, DE;Klein-Szanto, AJP
通讯作者：
Klein-Szanto, AJP
影响因子：
5.6
作者：
Arsenault, Dominique;Lucien, Fabrice;Dubois, Claire M.
通讯作者：
Dubois, Claire M.