Molecular Basis of Aneuploidy

非整倍体的分子基础

基本信息

批准号：
7196478
负责人：
DEBANANDA PATI
金额：
$ 22.58万
依托单位：
BAYLOR COLLEGE OF MEDICINE
依托单位国家：
美国
项目类别：
财政年份：
2006
资助国家：
美国
起止时间：
2006-03-07 至 2011-02-28
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7196478
关键词：
Address Affect Agreement Anaphase Aneuploidy Binding Biological Models Breast Breast Cancer Model Cancer Biology Cell Line Cells Chromosomal Instability Chromosomal Stability Chromosome Segregation Chromosome abnormality Chromosomes Chronic Class Cleaved cell Complementary DNA Contralateral Cultured Cells Data Development Diploidy Elements Endopeptidases Epithelial Cells Estrogens Fatty acid glycerol esters Gene Expression Genes Genetic Transcription Genotype Goals Gonadal Steroid Hormones Hormonal Hormone Responsive Hormones Human Human Characteristics Inbred BALB C Mice Incidence Indium Injection of therapeutic agent Knockout Mice Laboratories Lead Malignant Neoplasms Mammary Neoplasms Mammary Tumorigenesis Mammary gland Measures Messenger RNA Metaphase Mitosis Mitotic Modeling Molecular Mus Mutation Numbers Palpation Pathogenesis Peptide Hydrolases Physiological Pituitary Isograft Play Ploidies Preparation Progesterone Promoter Regions Protein Overexpression Protein p53 Proteins Publishing Regulation Research Personnel Risk Risk Factors Role Sequence Analysis Set protein Signal Transduction Sister Chromatid Steroids Structure System TP53 gene Techniques Testing Therapeutic Intervention Transcriptional Regulation Transgenic Mice Transgenic Organisms Transplantation Tumor Suppressor Proteins Tumorigenicity Validation Week Wild Type Mouse base cancer cell carcinogenesis cohesin cohesion in vivo in vivo Model innovation malignant breast neoplasm mouse model mutant neoplastic cell programs promoter research study segregation separase steroid hormone tumor tumor progression vector control

项目摘要

DESCRIPTION (provided by applicant): This proposal focuses on an important but unexplored problem - how steroid hormones, which are well known risk factors, interact with p53 mutations to produce aneuploidy and malignancy, and how the chromosomal segregation protein Separase is involved? Our sex-steroid dependent p53-mice preneoplastic breast cancer model allows a unique approach to this problem. In this model, steroidal induction in p53 mutant mammary glands results in chromosomal instability, aneuploidy and tumor formation analogous to that seen in majority of human breast cancers. We propose a paradigm that there is a set of proteins whose deregulation promotes aneuploidy (termed PR AN; Promoter of Aneuploidy) including chromosomal instability which results in loss or gain of whole or parts of chromosomes, and that PRAN proteins are interactively regulated by steroid hormones and the tumor suppressor p53. Our published and new preliminary data provide the first evidence that steroid hormones play a role in the regulation of mitotic proteins involved in sister chromatid cohesion and separation. We propose that the combined effect of mutation of the tumor suppressor p53 and signaling by steroid hormones produces aneuploidy in breast cancer by affecting expression of key proteins involved in chromosomal separation. We focuses on the elements that regulate chromosomal segregation, particularly sister chromatid cohesion/separation proteins, as candidate PRAN proteins, since chromosome missegregation during mitosis can lead to aneuploidy. A key gene in this analysis is ESPL1, which encodes an endopeptidase called Separase that separates joined sister chromatids by cleaving cohesin Rad21/SCC1/MCD1 during the metaphase to anaphase transition. The hypothesis is that hormonal stimulation of p53 null mouse mammary glands results in misexpression of the ESPL1 gene, thus promoting aneuploidy and breast cancer formation. This proposal applies in vivo transplantation of p53 mutant and wild type (WT) mammary cells that are stably transfected with ESPL1, and an ESPL1 transgenic mice model to test the PRAN paradigm following hormone treatment. Steroid and p53 regulation of ESPL1 at the transcriptional level is studied by characterizing the ESPL1 promoter region. These objectives will be accomplished by pursuing two specific aims: 1) Functional role of Separase overexpression in aneuploidy, and 2) Transcriptional regulation of ESPL1 gene expression. The proposed study not only elucidate underlying mechanisms of hormone-induced aneuploidy, a fundamental unresolved question in cancer biology, but also likely to identify a new class of proteins that are responsible for chromosomal instability and breast cancer progression.

描述（由申请人提供）：该提案关注一个重要但尚未探索的问题 - 类固醇激素（众所周知的危险因素）如何与 p53 突变相互作用产生非整倍性和恶性肿瘤，以及染色体分离蛋白分离酶如何参与其中？我们的性类固醇依赖性 p53 小鼠癌前乳腺癌模型为解决这个问题提供了独特的方法。在该模型中，p53 突变乳腺中的类固醇诱导导致染色体不稳定、非整倍性和肿瘤形成，类似于大多数人类乳腺癌中所见的情况。我们提出了一个范式，即存在一组蛋白质，其失调会促进非整倍性（称为 PR AN；非整倍性启动子），包括导致整个或部分染色体丢失或增加的染色体不稳定性，并且 PRAN 蛋白受到类固醇激素的交互调节和肿瘤抑制因子p53。我们发表的和新的初步数据提供了第一个证据，证明类固醇激素在调节参与姐妹染色单体凝聚和分离的有丝分裂蛋白中发挥作用。我们提出肿瘤抑制因子 p53 突变和类固醇激素信号传导的综合作用通过影响染色体分离中涉及的关键蛋白的表达而在乳腺癌中产生非整倍性。我们重点关注调节染色体分离的元件，特别是姐妹染色单体粘合/分离蛋白，作为候选 PRAN 蛋白，因为有丝分裂期间的染色体错误分离可能导致非整倍性。该分析中的一个关键基因是 ESPL1，它编码一种称为分离酶的内肽酶，可在中期到后期的转变过程中通过裂解粘连蛋白 Rad21/SCC1/MCD1 来分离连接的姐妹染色单体。该假说认为，p53 缺失小鼠乳腺的激素刺激会导致 ESPL1 基因的错误表达，从而促进非整倍体和乳腺癌的形成。该提案应用稳定转染 ESPL1 的 p53 突变体和野生型 (WT) 乳腺细胞的体内移植，以及 ESPL1 转基因小鼠模型来测试激素治疗后的 PRAN 范例。通过表征 ESPL1 启动子区域，研究了 ESPL1 在转录水平上的类固醇和 p53 调节。这些目标将通过追求两个具体目标来实现：1) 分离酶过表达在非整倍性中的功能作用，以及 2) ESPL1 基因表达的转录调控。拟议的研究不仅阐明了激素诱导的非整倍性的潜在机制（这是癌症生物学中尚未解决的基本问题），而且还可能鉴定出一类导致染色体不稳定和乳腺癌进展的新蛋白质。