CK2-dependent phosphorylation of Progesterone Receptors mediates proliferative si

孕酮受体的 CK2 依赖性磷酸化介导增殖性 si

• 批准号: 8531690
• 负责人: Christy Hagan
• 金额: $ 9.75万
• 依托单位: UNIVERSITY OF MINNESOTA
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-09-23 至 2015-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8531690
• 关键词: Binding; Binding Sites; Biology; Breast; Breast Cancer Cell; Breast Cancer Prevention; Breast Carcinoma; Cancerous; Carcinoma; Cell Maintenance; Cell Proliferation; Cells; Data; Development; Docking; Estrogen Receptors; Event; Gene Expression Regulation; Gene Targeting; Genes; Genetic Transcription; Genome; Genomics; Goals; Hyperplasia; Knockout Mice; Ligands; Maintenance; Mammary Neoplasms; Mammary gland; Mediating; Mus; N-terminal; Ovarian Steroid Hormone; Phosphorylation; Progesterone; Progesterone Receptors; Protein Binding; Protein Isoforms; Proteins; Recruitment Activity; Regulation; Relative (related person); Research Proposals; STAT5A gene; Serine; Signal Transduction; Stem cells; Steroid Receptors; Tissues; Uterus; base; breast lesion; genome-wide; hormone therapy; malignant breast neoplasm; mouse development; novel; prevent; progesterone receptor A; progesterone receptor B; promoter; receptor; tumor progression

DESCRIPTION (provided by applicant): Progesterone is an ovarian steroid hormone essential for breast development. The progesterone receptor (PR) exists primarily in two co-expressed isoforms, PR-A and PR-B. Studies from knockout-mice have shown that PR-B is required for proliferative signaling during mammary gland alveologenesis. In contrast, PR-A is required for uterine development, where progesterone inhibits proliferation. Very little is understood regarding regulation of PR tissue- and isoform-specific transcription. How are isoform-specific mitogenic (PR-B in the breast) and inhibitory/differentiative (PR-A in the uterus) effects achieved? PR-A and PR-B are most often co-expressed in the same tissues, and cells that express only a single PR isoform are rare, except in breast cancer where the normal 1:1 ratio is frequently altered. Selective PR isoform inhibition (blocking pro-proliferative effects of PR-B while preserving the protective or anti-proliferative effects of PR-A) would represent significant progress in breast cancer prevention and/or treatment. PR is highly post-translationally modified. Phosphorylation, primarily on PR-B N-terminal serine residues, significantly alters receptor stability, localization, transcriptional activity and promoter selectvity. Our preliminary data suggest that the basis for PR-B-specific proliferative actions in breast cancer cells involves ck2-dependent selective phosphorylation of PR-B Ser81 via a unique protein interaction domain, the common docking (CD) domain, found exclusively in PR-B but not PR-A. Phosphorylation of PR-B Ser81 regulates a highly specific subset of proliferative and pro-survival genes, including selected PR-regulated genes known to modulate the mammary stem cell compartment, such as Wnt1 and STAT5A. Additionally, our data suggest that STAT5A may serve as a "pioneer factor", an early genomic binding partner that recruits/directs phospho-Ser81-PR-B-specific gene regulation. The goal of this research proposal is to determine how proteins that interact with PR-B via the CD domain regulate direct phosphorylation of PR-B on Ser81, thereby dictating PR-B isoform-specific transcriptional events at genes important for breast cancer cell proliferation, pro-survival, and expansion of the stem cell compartment. Hypothesis: PR and STAT5 co-regulate a specific subset of phospho-PR-B target genes (through CD domain- dependent recruitment of MKP3 and ck2, followed by ck2-mediated phosphorylation of PR-B Ser81) that regulate breast cancer cell proliferation and pro-survival, in part via modulation of the mammary stem cell compartment; selected genes are regulated by phospho-PR-B in the absence of ligand. ck2-dependent activation of PR-B may accelerate mammary tumor development and/or drive early breast cancer progression.

描述（由申请人提供）：孕激素是一种卵巢类固醇激素，对乳房发育至关重要。孕激素受体（PR）主要存在于两种共表达的亚型中，PR-A和PR-B。来自基因敲除小鼠的研究表明，PR-B是乳腺肺泡发生期间增殖信号所必需的。相反，PR-A是子宫发育所必需的，其中孕酮抑制增殖。关于PR组织和亚型特异性转录的调控知之甚少。同种型特异性促有丝分裂（乳腺中的PR-B）和抑制/分化（子宫中的PR-A） 取得的效果？PR-A和PR-B通常在相同的组织中共同表达，并且仅表达单一PR亚型的细胞是罕见的，除了在乳腺癌中正常的1：1比例经常改变。选择性PR亚型抑制（阻断PR亚型的促增殖作用） PR-B同时保留PR-A的保护或抗增殖作用）将代表乳腺癌预防和/或治疗的显著进展。PR是高度事后修改的。磷酸化，主要对PR-B N-末端丝氨酸残基，显着改变受体的稳定性，定位，转录活性和启动子选择性。我们的初步数据表明，在乳腺癌细胞中PR-B特异性增殖作用的基础涉及CK 2依赖的选择性磷酸化PR-B Ser 81通过一个独特的蛋白质相互作用域，共同的对接（CD）域，发现专门在PR-B，但不是PR-A。PR-B Ser 81的磷酸化调节增殖和促存活基因的高度特异性子集，包括已知调节乳腺干细胞区室的选定PR调节基因，如Wnt 1和STAT 5A。此外，我们的数据表明，STAT 5A可能作为一个“先锋因子”，招募/指导磷酸化Ser 81-PR-B特异性基因调控的早期基因组结合伴侣。这项研究计划的目标是确定通过CD结构域与PR-B相互作用的蛋白质如何调节PR-B在Ser 81上的直接磷酸化，从而在对乳腺癌细胞增殖，促生存和干细胞室扩增重要的基因上决定PR-B亚型特异性转录事件。 假设：PR和STAT 5共调节磷酸-PR-B靶基因的特定亚组（通过MKP 3和ck 2的CD结构域依赖性募集，随后是ck 2介导的PR-B Ser 81磷酸化），其部分通过调节乳腺干细胞区室来调节乳腺癌细胞增殖和促存活;所选基因在不存在配体的情况下由磷酸-PR-B调节。PR-B的CK 2依赖性激活可能加速乳腺肿瘤的发展和/或驱动早期乳腺癌进展。