Role of the DNA Damage Response in Prostate Cancer Initiation

DNA 损伤反应在前列腺癌发生中的作用

• 批准号: 8555289
• 负责人: Edward P Gelmann
• 金额: $ 25.04万
• 依托单位: COLUMBIA UNIVERSITY HEALTH SCIENCES
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-09-16 至 2016-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8555289
• 关键词: 8p21; Abate; Affect; Androgen Receptor; Androgens; Binding; Cancer Family; Cell Aging; Cell Culture Techniques; Cell Survival; Cells; Cellular Stress; Cessation of life; Characteristics; Chromosomal Loss; Chromosomal Rearrangement; Collaborations; Complex; DNA; DNA Damage; DNA Sequence Rearrangement; Data; Development; Diagnosis; Down-Regulation; ERG gene; Environmental Exposure; Epigenetic Process; Epithelial; Epithelial Cells; Epithelium; Event; Frequencies; Gene Dosage; Gene Fusion; Gene Rearrangement; Genetic; Genome; Goals; Homeobox Genes; Human; Hyperplasia; In Vitro; Inflammatory; Inherited; Intraepithelial Neoplasia; Investigation; LNCaP; Laboratories; Lead; Link; Malignant neoplasm of prostate; Mediating; Molecular; Mus; Mutant Strains Mice; Mutation; NKX3-1 gene; Pathway interactions; Phenotype; Phosphorylation; Phosphotransferases; Play; Post-Translational Protein Processing; Predisposition; Prostate; Prostatic Neoplasms; Proteins; Publishing; Relative (related person); Role; Services; Signal Transduction; Staging; Stem cells; Stimulus; TMPRSS2 gene; Time; Tissues; Tumor Suppression; Tumor Suppressor Proteins; Tyrosine Phosphorylation; Up-Regulation; Work; base; cancer cell; cancer initiation; cancer therapy; carcinogenesis; cell growth; cytokine; early onset; high risk; homeodomain; in vivo; insight; kindred; knock-down; men; molecular pathology; mouse model; programs; prostate cancer prevention; prostate carcinogenesis; protein expression; research study; response; tumor initiation; tumor progression

This project investigates the role of NKX3.1 in protection against DNA damage in the prostate epithelium, which may provide a key mechanism for its function in tumor suppression, NKX3.I is a prostate specific homeobox gene located on 8p21, the target for the most frequent chromosomal loss in human prostate cancer. NKX3.I is also a tumor suppressor for which reduced protein expression is sufficient to deregulate prostate epithelial cell growth and cause Intraepithelial neoplasia; moreover, Nkx3.1 haploinsufficiency results in prostate epithelial dysplasia in mice. Consistent with its role as a tumor suppressor in human prostate cancer, we have shown that an Inactivating mutation In the NKX3.I homeodomain cosegregates with early onset prostate cancer in a prostate cancer family. In recent studies, we have shown that NKX3.1 enhances cell survival after DNA damage and affects the earliest events in recognition of DNA breaks, including formation of YH2AX foci and phosphorylation of ATM. Based on our hypothesis that a key mechanism by which NKX3.1 loss contributes to tumor initiation is through its impact on the DNA damage response, our studies will define the mechanistic role of NKX3.I in the DNA damage response in vitro, as well as its impact on DNA damage in vivo. We also will determine whether NKX3.I mediates the susceptibility of prostate cells to formation of the characteristic TMPRSS2- ERG chromosomal rearrangement that occurs in approximately 50% of prostate cancers. Taken together, our three aims will delineate the role of NKXS.I in the DNA damage response in distinct contexts, thereby providing a comprehensive investigation of this key mechanism of tumor suppression. In Aim 1, our experiments will define the dynamics of the functional interaction between NKX3.1 and ATM, which occurs within minutes of DNA damage. In Aim 2, we will determine whether Nkx3.I gene copy number affects the DNA damage response in vivo in the prostate epithelium, and particularly in prostate epithelial stem cells. Finally, in Aim 3, using unique lines of LNCaP cells that we have derived, we will determine whether NKX3.1 affects the frequency of TMPRSS2-ERG gene rearrangements. These proposed studies will be highly integrated with the overall program project. Notably, the experiments in Aim 2 include quantitative immunostaining analyses in collaboration with Core A, the work in Aim 2 on the prostate stem cells will be performed in collaboration with Michael Shen (Project 1), and the entirety of this project is linked to the molecular analyses of Nkx3.1 in cellular senescence by Cory Abate-Shen (Project 2).

该项目研究了NKX3.1在预防前列腺上皮中防止DNA损伤的作用，这可能为其在肿瘤抑制中的功能提供关键机制，NKX3.i是位于8p21上的前列腺特异性同源基因，是人类前列腺癌中最常见的染色体损失的靶标。 NKX3.i也是一种肿瘤抑制剂，降低的蛋白质表达足以消除前列腺上皮细胞生长并引起上皮内肿瘤。此外，NKX3.1单倍体不足会导致小鼠前列腺上皮发育不良。与其在人类前列腺癌中作为肿瘤抑制剂的作用一致，我们表明NKX3.i同源域中的灭活突变与前列腺癌家族的早期前列腺癌cosedomain cosedomain cosedomain。在最近的研究中，我们表明NKX3.1在DNA损伤后增强了细胞存活，并影响了识别DNA断裂的最早事件，包括形成YH2AX灶和ATM的磷酸化。 基于我们的假设，即NKX3.1损失造成肿瘤引发的关键机制是通过其对DNA损伤反应的影响，我们的研究将定义NKX3.i在体外的DNA损伤反应中的机械作用，以及其对体内DNA损伤的影响。我们还将确定nkx3.i是否介导了前列腺细胞对特征性TMPRSS2- ERG染色体重排的形成的敏感性，该染色体重排在大约50％的前列腺癌中。综上所述，我们的三个目标将描述nkxs.i在不同背景下DNA损伤反应中的作用，从而对这种抑制肿瘤的关键机制进行了全面的研究。在AIM 1中，我们的实验将定义NKX3.1和ATM之间功能相互作用的动力学，该动力发生在DNA损伤后数分钟内发生。在AIM 2中，我们将确定NKX3.i基因拷贝数是否会影响前列腺上皮体内的DNA损伤反应，尤其是在前列腺上皮干细胞中。最后，在AIM 3中，使用我们得出的LNCAP单元的独特线条，我们将确定NKX3.1是否会影响TMPRSSS2-GER基因重排的频率。这些建议的研究将与整个计划项目高度融合。值得注意的是，AIM 2中的实验包括与Core A合作的定量免疫染色分析，AIM 2中的工作2将与Michael Shen（项目1）合作进行，并且该项目的整体与Cory Abate Abate Abate-Shen（Project-Shen）（Project 2）中NKX3.1的分子分析有关。