Identifying a Hypoxia Inducible Factor target profile in Renal Cell Carcinoma tum

描述（由申请人提供）：肾细胞癌（RCC）是一种高度流行的恶性肿瘤，死亡率高。散发性和生殖系突变和/或von Hippel-Lindau（VHL）肿瘤抑制基因的缺失与RCC的不同风险水平有关。VHL疾病患者具有一个野生型VHL等位基因和一个失活/突变的VHL等位基因。当VHL的正常拷贝丢失或失活时发生肿瘤形成。鉴于VHL 2B错义突变赋予RCC高风险，拟议的项目旨在确定VHL失活后肾细胞中发生的关键分子变化，这些变化可以提供RCC肿瘤形成的见解。众所周知，在正常氧条件下，功能性pVHL蛋白靶向缺氧诱导因子（HIF）进行蛋白质体降解，而在低氧条件下或突变的VHL等位基因下，VHL不能调节HIF-1亚基。HIF-1亚基与HIF-2亚基二聚化，易位到细胞核并负责基因的转录激活。一些HIF基因靶点已被确定;最值得注意的是那些对血管生成和葡萄糖代谢重要的基因，它们通常在RCC和其他恶性肿瘤中上调。本项目的重点是通过比较VHL状态对HIF-11和/或HIF-21基因表达水平的差异，使用转基因小鼠模型来确定HIF基因的靶基因谱。为了更好地理解与RCC肿瘤形成相关的遗传变化，将使用来自新生儿条件性Vhl无效和Vhl 2B转基因小鼠系的原代上皮肾细胞，并将其收获并在离体系统中最低限度地操作。之后，这些细胞将被重新引入它们的天然环境，免疫受损小鼠的肾包膜，以研究它们的致瘤潜力。将鉴定生成的合并细胞系的细胞组成，以研究哪种细胞类型最有发生肿瘤的风险。无论肾癌是由于VHL疾病还是散发性突变，这项研究对公众来说都非常重要，因为我们必须了解肾细胞发生了什么变化才能成为致瘤性。拟议的研究将确定风险最高的细胞群，并分析导致肿瘤生长的风险细胞群中的分子变化，以及确定这些变化的HIF基因靶向特征，以便更深入地了解RCC肿瘤发生。

DESCRIPTION (provided by applicant): Renal cell carcinoma (RCC) is a highly prevalent malignancy with a high mortality rate. Sporadic and germline mutations and/or loss of the von Hippel-Lindau (VHL) tumor suppressor gene have been linked to varying levels of risk for RCC. VHL disease patients have one wild type VHL allele and one inactivated/mutated VHL allele. Tumor formation occurs when the normal copy of VHL is lost or inactivated. Given that VHL 2B missense mutation confers a high risk for RCC, the proposed project aims to identify key molecular changes that occur in renal cells following VHL inactivation that can provide insight into RCC tumor formation. It is well understood that functional pVHL protein under normal oxygen conditions targets hypoxia inducible factors (HIF) for proteosomal degradation, while under low oxygen conditions or mutated VHL allele, VHL fails to regulate HIF-1 subunits. HIF-1 subunits dimerize with HIF-2 subunits, translocate to the nucleus and are responsible for transcriptional activation of genes. Some HIF gene targets have been identified; most notably those important for angiogenesis and glucose metabolism, which are normally upregulated in RCC and other malignant tumors. The focus of this project is to identify a HIF gene target profile by comparing levels of gene expression when HIF-11 and/or HIF-21 are differentially regulated by VHL status using transgenic mouse models. To better understand the genetic changes associated with RCC tumor formation, primary epithelial kidney cells from newborn conditional Vhl null and Vhl 2B transgenic mouse lines will be used and will be harvested and minimally manipulated in an ex vivo system. After which, these cells will be reintroduced to their native environment, renal capsules of immunocompromised mice, to study their tumorigenic potential. The cellular composition of the generated pooled cell lines wilI be identified to investigate which cell type is most at risk for developing tumorigenesis. Whether renal carcinoma is due to VHL disease or sporadic mutations, this study bears great weight to the public, as it is imperative that we understand what changes occur in kidney cells to become tumorigenic. The proposed research will identify the most at-risk cell population and analyze the molecular changes in this at-risk cell population that result in tumor growth as well as identify a HIF gene target profile for these changes in order to have greater insight into RCC tumorigenesis.