Functional Analysis of the von Hippel-Lindau Disease Tumor Suppressor Gene

冯·希佩尔-林道病肿瘤抑制基因的功能分析

基本信息

批准号：
10671488
负责人：
YAO Masahiro
金额：
$ 2.05万
依托单位：
Yokohama City University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1998
资助国家：
日本
起止时间：
1998 至 1999
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10671488/
关键词：
VHL gene tumor suppressor gene renal cell carcinoma 腎細胞癌 DHL遺伝子

项目摘要

We found that, in normal human renal proximal tubule epithelial cells, the steady-state amount of VHL protein is strictly regulated by cell density. The cellular VHL content is more than 100-fold higher in dense cultures than in sparse cultures. The growth rates of renal cell cacinoma cells lacking an intact VHL gene and their derivatives with wild-type or mutant VHL expression vector do not differ significantly when they are growing in log-phase. Importantly, however, there is a difference when they reach confluency : cells lacking wild-type VHL grew continuously, while cells expressing exogenous VHL protein showed relatively limited cell growth. VHL protein functions as a growth suppressor at high cell density, and this might be the basis of the tumor suppressor function of VHL. We investigated the role of the VHL gene in CNS development using rodent CNS progenitor cells. We show that expression of the VHL protein is correlated with neuronal differentiation but not with glial differe … More ntiation in CNS progenitor cells, and we also show that VHL gene transduction induces neuronal differentiation. In addition, a VHL mRNA antisense oligonucleotide inhibits differentiation of CNS progenitor cells and up-regulates their cell cycle. The VHL protein contains two domains, alpha and beta. We report that the beta-domain interacts directly with atypical PKC isotypes, PKC zeta and PKC lambda. Further, the regulatory domain of aPKC is sufficient for this direct protein-protein interaction. To investigate the potential role of the PTEN gene in renal tumorigenesis, we searched for abnormalities of the gene in 68 primary renal-cell carcinomas (RCCs) as well as in 17 renal carcinoma-derived cell lines. Five of 68 (7.5 %) primary RCCs exhibited intragenic mutations, and 1 of 17 (5.9 %) cell lines had an insertion mutation. Four of the 5 primary tumors with PTEN mutation were high-grade, advanced clear-cell RCCs with distant metastases or renal vein tumor invasions, resulting in poor prognostic courses. PTEN mutation is observed m a subset of RCCs and that, especially in clear-cell RCCs, it occurs as a late-stage event and may contribute to the invasive and/or metastatic tumor phenotype. Less

我们发现，在正常人肾近曲小管上皮细胞中，VHL蛋白的稳态量受到细胞密度的严格调节，密集培养物中的细胞VHL含量比稀疏培养物高100倍以上。缺乏完整 VHL 基因的肾细胞癌细胞及其具有野生型或突变型 VHL 表达载体的衍生物在对数生长期生长时没有显着差异，但重要的是，当它们达到对数期时，存在差异。融合：缺乏野生型VHL的细胞持续生长，而表达外源VHL蛋白的细胞在高细胞密度下表现出相对有限的细胞生长抑制作用，这可能是VHL的肿瘤抑制功能的基础。使用啮齿动物中枢神经系统祖细胞研究了 VHL 基因在中枢神经系统发育中的作用，我们发现 VHL 蛋白的表达与神经元分化相关，但与中枢神经系统祖细胞中的神经胶质细胞分化无关。我们还表明，VHL 基因转导可诱导神经元分化，此外，VHL mRNA 反义寡核苷酸可抑制 CNS 祖细胞的分化并上调其细胞周期。 aPKC 结构域与非典型 PKC 同种型、PKC zeta 和 PKC lambda 直接相互作用。此外，aPKC 的调节结构域足以研究这种直接的蛋白质-蛋白质相互作用。 PTEN 基因在肾肿瘤发生中的作用，我们在 68 个原发性肾细胞癌 (RCC) 以及 17 个肾癌衍生细胞系中寻找该基因的异常，68 个原发性 RCC 中的 5 个 (7.5%) 表现出基因内突变，1 个表现出基因内突变。 17 个细胞系 (5.9%) 具有插入突变，5 个具有 PTEN 突变的原发性肿瘤中有 4 个是具有远处转移的高级别、晚期透明细胞 RCC。在部分 RCC 中观察到 PTEN 突变导致肾或静脉肿瘤侵袭，尤其是在透明细胞 RCC 中，它作为晚期事件发生，可能导致侵袭性和/或转移性肿瘤表型。。较少的