Zhang Binglin, Tomita Yasuhiko, Qiu Ying, He Juxiang, Morii Eiichi, Noguchi Shinzaburo, Aozasa Katsuyuki
Department of Pathology, Osaka University Graduate School of Medicine, Suita, Osaka 565-0871, Japan.
Biochem Biophys Res Commun. 2007 May 11;356(3):536-41. doi: 10.1016/j.bbrc.2007.02.160. Epub 2007 Mar 9.
Enhanced expression of valosin-containing protein (VCP) correlates with invasion and metastasis of cancers. To clarify the transcription mechanism of VCP, human and mouse genomic sequence was compared, revealing a 260 bp DNA sequence in the 5'-flanking region of VCP gene to be highly conserved between the two, in which binding motif of E74-like factor 2/new Ets-related factor (ELF2/NERF) was identified. Chromatin immunoprecipitation assay showed binding of ELF2/NERF to the 5'-flanking region of VCP gene. Knock-down of ELF2/NERF by siRNA decreased expression level of VCP. Viability of cells under tumor necrosis factor-alpha treatment significantly reduced in ELF2/NERF-knock-down breast cancer cell line. Immunohistochemical analysis on clinical breast cancer specimens showed a correlation of nuclear ELF2/NERF expression with VCP expression and proliferative activity of cells shown by Ki-67 immunohistochemistry. These findings indicate that ELF2/NERF promotes VCP transcription and that ELF2/NERF-VCP pathway might be important for cell survival and proliferation under cytokine stress.
含缬酪肽蛋白(VCP)的表达增强与癌症的侵袭和转移相关。为阐明VCP的转录机制,对人和小鼠的基因组序列进行了比较,结果显示VCP基因5'侧翼区域有一段260 bp的DNA序列在两者之间高度保守,其中鉴定出了E74样因子2/新Ets相关因子(ELF2/NERF)的结合基序。染色质免疫沉淀试验表明ELF2/NERF与VCP基因的5'侧翼区域结合。通过小干扰RNA敲低ELF2/NERF可降低VCP的表达水平。在肿瘤坏死因子-α处理下,ELF2/NERF敲低的乳腺癌细胞系中细胞活力显著降低。对临床乳腺癌标本的免疫组织化学分析显示,核ELF2/NERF表达与VCP表达以及Ki-67免疫组织化学所示的细胞增殖活性相关。这些发现表明ELF2/NERF促进VCP转录,并且ELF2/NERF-VCP途径可能在细胞因子应激下对细胞存活和增殖很重要。