The role and regulation of cell survival in uterine functions.

细胞存活在子宫功能中的作用和调节。

• 批准号: RGPIN-2019-06151
• 负责人: Asselin, Eric
• 金额: $ 3.64万
• 依托单位: Université du Québec à Trois-Rivières
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2021
• 资助国家: 加拿大
• 起止时间: 2021-01-01 至 2022-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=738742
• 关键词: role; regulation; cell; survival; uterine

BACKGROUND & RATIONALE: Prostate apoptosis response-4 (Par-4), a novel regulator of apoptosis as well as epithelial to mesenchymal transition (EMT), is active in a variety of cell lines and knockout mice show reduced lifespan and enhanced abnormal cell proliferation in the endometrium. We demonstrated that Par-4 is a direct target of caspase-3 during apoptosis induction and that the resulting cleaved fragment is capable of inducing programmed cell death through its translocation to nucleus. We also showed that TGFß increases EMT of endometrial cells and that it can regulate the long form of Par-4 in vitro. Interestingly, preliminary evidence gathered using cell lines in our laboratory and publically available databases suggest that 17ß-estradiol (E2) can negatively regulate Par-4. E2, an important female sex hormone, act through two known pathways, the canonical genomic pathway involving its intracellular receptor ER? which bind to estrogen-response elements (ERE) in DNA and the non-genomic pathway involving the PI-3K/Akt signaling action, an important survival and proliferation actor in the endometrium. How E2 action can be modulated through the inhibition of the pro-apoptotic factor Par-4 is unknown and it is crucial that we understand the molecular mechanisms controlling these functions. HYPOTHESES: 1) E2 reduces Par-4 expression and modifies its activity as well as its localization, abrogating its ability to induce apoptosis in endometrial cells. Therefore, inhibition of E2 activity should reinstate Par-4 expression and activity. This hypothesis will be explored in Obj1. 2) Par-4 is negatively regulated through the non-genomic E2 pathway or through PI3/Akt axis; this pathway would also influence Par-4 localization through TGFß signaling, which plays a pivotal role in cell survival and EMT/MET. This hypothesis will be explored in Obj2. The overall and long-term objective of the proposed research program is to examine and understand the regulation of expression as well as the endocrine, paracrine and autocrine activity of Par-4 in the regulation of endometrial cell fate. EXPERIMENTAL APPROACHES: Known estrogen responsive and non-responsive endometrial cells will be used for in vitro studies. Mouse pregnancy and induced decidualization will be used to study TGF-ß and Par-4 axis in the EMT process. SPECIFIC OBJECTIVES: 1) To determine the role of E2, through ERa and PI-3K/Akt pathway, in the control of Par-4 expression, localization and activity; 2) To elucidate how Par-4 differentially induce apoptosis and EMT and the key mechanisms governing these processes. INNOVATION & SIGNIFICANCE: A deeper understanding of E2 and TGFß-dependent Par-4 regulation is essential in uterine functions. Information gained from these studies will also help to identify the molecular mechanisms controlling apoptosis/survival and other types of cell fate (migration, invasion, EMT/MET) and will provide important clues in our understanding of reproductive functions.

背景与理论：前列腺细胞凋亡反应-4(Par-4)是一种新的细胞凋亡调节因子，也是上皮向间充质转化(EMT)的调节因子，它在多种细胞系中都很活跃，基因敲除小鼠表现出寿命缩短和子宫内膜异常细胞增殖增强。我们证明了PAR-4是caspase-3在诱导细胞凋亡过程中的直接靶点，并且所产生的切割片段能够通过其移位到细胞核来诱导细胞程序性死亡。我们还发现，在体外，转化生长因子能够增加子宫内膜细胞的EMT，并且可以调节PAR-4的长形。有趣的是，使用我们实验室的细胞系和公共数据库收集的初步证据表明，17？雌二醇(E_2)可以负向调节PAR-4。雌二醇是一种重要的女性性激素，它通过两条已知的途径发挥作用，其中典型的基因组途径涉及其细胞内受体ER？它们与DNA中的雌激素反应元件(ERE)结合，以及参与PI-3K/Akt信号转导的非基因组途径，PI-3K/Akt信号通路是子宫内膜重要的生存和增殖因子。E2的作用如何通过抑制促凋亡因子PAR-4来调节是未知的，我们理解控制这些功能的分子机制是至关重要的。假设：1)E2降低了PAR-4的表达，改变了其活性和定位，取消了其诱导子宫内膜细胞凋亡的能力。因此，抑制E2活性应恢复PAR-4的表达和活性。这一假设将在Obj1中进行探讨。2)PAR-4通过非基因组的E2途径或通过PI3/Akt轴被负调控，该途径还通过在细胞存活和EMT/MET中起关键作用的转化生长因子？信号影响PAR-4的定位。这一假设将在Obj2中进行探讨。该研究计划的总体和长期目标是检查和了解PAR-4在调控子宫内膜细胞命运中的表达调控以及内分泌、旁分泌和自分泌活性。实验方法：已知的雌激素反应性和非反应性子宫内膜细胞将用于体外研究。将利用小鼠妊娠和诱导蜕膜形成来研究EMT过程中的转化生长因子-β和PAR-4轴。具体目的：1)通过Era和PI-3K/Akt通路，确定E2在调控PAR-4表达、定位和活性中的作用；2)阐明PAR-4如何差异性地诱导细胞凋亡和EMT，以及调控这些过程的关键机制。创新和意义：更深入地了解依赖于雌二醇和转化生长因子的PAR-4调控对子宫功能至关重要。从这些研究中获得的信息还将有助于确定控制细胞凋亡/存活和其他类型细胞命运(迁移、侵袭、EMT/MET)的分子机制，并将为我们理解生殖功能提供重要线索。