CLCP1 interacts with semaphorin 4B and regulates motility of lung cancer cells
CLCP1 interacts with semaphorin 4B and regulates motility of lung cancer cells
复制标题
DOI：
10.1038/sj.onc.1210183
复制
发表时间：
2007-06-07
期刊：
影响因子：
8
通讯作者：
Osada, H.
中科院分区：
文献类型：
--
作者：
Nagai, H.;Sugito, N.;Osada, H.
我们之前从NCI-H460肺癌细胞系中建立了一个高转移性亚系LNM 35，并证明了LNM 35和肺癌标本中新型基因CLCP 1（CUB，LCCL同源性，凝血因子V/VIII同源结构域蛋白）的上调。在这项研究中，我们专注于该基因在癌症转移中的潜在作用。首先，我们建立了稳定的LNM 35 RNA干扰克隆，其中CLCP 1表达被RNA干扰抑制，并发现它们的运动性显着降低，但生长率没有改变。接下来，体外选择噬菌体展示文库证明展示与脑信号蛋白4 B（SEMA 4 B）的Sema结构域内的序列相似的肽的噬菌体克隆与LNM 35相互作用。免疫沉淀实验证实了CLCP 1与SEMA 4 B的相互作用，在SEMA 4 B存在下，通过泛素化和蛋白酶体降解增强CLCP 1蛋白的调节。这些结果首次表明CLCP 1在细胞运动中起作用，同时它们还表明其配体中至少有一种是SEMA 4 B，并且它们的相互作用介导CLCP 1的蛋白酶体降解。虽然CLCP 1和SEMA 4 B之间相互作用的生理作用仍有待研究，但这种新基因可能成为抑制肺癌转移的治疗靶点。
We previously established a highly metastatic subline, LNM35, from the NCI-H460 lung cancer cell line, and demonstrated upregulation of a novel gene, CLCP1 ( CUB, LCCL-homology, coagulation factor V/VIII homology domains protein), in LNM35 and lung cancer specimens. In this study, we focused on the potential roles of that gene in cancer metastasis. First, we established stable LNM35 RNAi clones, in which CLCP1 expression was suppressed by RNAi, and found that their motility was significantly reduced, although growth rates were not changed. Next, in vitro selection of a phage display library demonstrated that a phage clone displaying a peptide similar to a sequence within the Sema domain of semaphorin 4B ( SEMA4B) interacted with LNM35. Immunoprecipitation experiments confirmed interaction of CLCP1 with SEMA4B, regulation of CLCP1 protein by ubiquitination and proteasome degradation enhanced in the presence of SEMA4B. These results are the first to indicate that CLCP1 plays a role in cell motility, whereas they also showed that at least one of its ligands is SEMA4B and that their interaction mediates proteasome degradation by CLCP1. Although the physiological role of the interaction between CLCP1 and SEMA4B remains to be investigated, this novel gene may become a target of therapy to inhibit metastasis of lung cancers.