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: 8278299
• 负责人: Christy Hagan
• 金额: $ 9.21万
• 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 2014-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8278299
• 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. PUBLIC HEALTH RELEVANCE: The goal of this research proposal is to determine how proteins that interact with the progesterone receptor (PR) regulate its direct phosphorylation, thereby dictating PR isoform-specific transcriptional events at genes important for breast cancer cell proliferation, pro-survival, and expansion of the stem cell compartment. Understanding how PR isoform-specific regulation is achieved may allow us to modulate/inhibit the proliferative actions of PR in the breast, while preserving protective anti-proliferative activities in other tissues. These studies could open the way to new treatments that may prevent or reverse the development of early cancerous steroid receptor positive breast lesions and/or provide novel PR-based additions to the current repertoire of largely estrogen receptor-based endocrine therapies.

描述（由申请人提供）：黄体酮是一种对乳​​房发育至关重要的卵巢类固醇激素。孕酮受体 (PR) 主要以两种共表达亚型存在：PR-A 和 PR-B。基因敲除小鼠的研究表明，PR-B 是乳腺肺泡发生过程中增殖信号所必需的。相反，PR-A 是子宫发育所必需的，而孕酮会抑制增殖。关于 PR 组织和同工型特异性转录的调节知之甚少。异构体特异性促有丝分裂（乳房中的 PR-B）和抑制/分化（子宫中的 PR-A）如何 达到的效果？ PR-A 和 PR-B 通常在同一组织中共表达，仅表达单一 PR 亚型的细胞很少见，但乳腺癌除外，正常的 1:1 比例经常发生改变。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/或治疗方面的重大进展。 PR 是高度翻译后修饰的。主要针对 PR-B N 端丝氨酸残基的磷酸化显着改变受体稳定性、定位、转录活性和启动子选择性。我们的初步数据表明，乳腺癌细胞中 PR-B 特异性增殖作用的基础涉及 PR-B Ser81 通过独特的蛋白质相互作用结构域（常见对接 (CD) 结构域）进行 ck2 依赖性选择性磷酸化，该结构域仅存在于 PR-B 而不是 PR-A。 PR-B Ser81 的磷酸化可调节高度特异性的增殖和促存活基因子集，包括已知可调节乳腺干细胞区室的选定 PR 调节基因，例如 Wnt1 和 STAT5A。此外，我们的数据表明 STAT5A 可能充当“先锋因子”，即招募/指导磷酸-Ser81-PR-B 特异性基因调控的早期基因组结合伴侣。本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 Ser81 上的直接磷酸化，从而决定对乳腺癌细胞增殖、促存活和干细胞区室扩张重要的基因上的 PR-B 亚型特异性转录事件。 假设：PR 和 STAT5 共同调节磷酸化 PR-B 靶基因的特定子集（通过 CD 结构域依赖性招募 MKP3 和 ck2，然后进行 ck2 介导的 PR-B Ser81 磷酸化），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；在没有配体的情况下，选定的基因受磷酸-PR-B 的调节。 PR-B 的 ck2 依赖性激活可能会加速乳腺肿瘤的发展和/或驱动早期乳腺癌的进展。 公共健康相关性：本研究提案的目标是确定与孕酮受体 (PR) 相互作用的蛋白质如何调节其直接磷酸化，从而决定对乳腺癌细胞增殖、促存活和干细胞区室扩张重要的基因的 PR 亚型特异性转录事件。了解 PR 异构体特异性调节是如何实现的，可以让我们调节/抑制 PR 在乳房中的增殖作用，同时保留其他组织中的保护性抗增殖活性。这些研究可能为新疗法开辟道路，这些疗法可能预防或逆转早期癌性类固醇受体阳性乳腺病变的发展，和/或为目前主要基于雌激素受体的内分泌疗法提供新的基于 PR 的补充。