Role of the CXCR4/CXCL12 axis in endometriosis

描述（由申请人提供）：子宫内膜异位症与癌症一样，也显示出增殖、侵袭和血管生成增加的特征;然而，这种雌激素依赖性侵袭性疾病的具体机制仍然未知。子宫内膜的两种主要细胞成分，即上皮细胞（EEC）和基质细胞（HESC），显示出CXCR 4和CXCL 12蛋白的差异表达：子宫内膜上皮细胞表达的CXCR 4水平高于基质细胞;相反，子宫内膜基质细胞表达的CXCL 12水平更高，这与之前其他人和我们实验室的报道一致。此外，我们发现，CXCR 4表达的差异调节雌二醇（E2）和孕酮（P4）在子宫内膜细胞系。最后，我们还发现CXCR 4在子宫内膜异位症大鼠模型和人类子宫内膜异位组织中显著过表达。与分泌对照子宫内膜相比，增生性病变中CXCR 4蛋白的表达显著更高，分泌对照子宫内膜表达该趋化因子受体的最高表达。基于这些初步观察，我们假设CXCR 4-CXCL 12轴的激活是子宫内膜异位症发生和发展的关键步骤。具体而言，该建议旨在研究CXCR 4信号转导的作用，其配体，CXCL 12，在促进细胞增殖，侵袭，和血管生成的子宫内膜异位症。推动这一提议的主要假设是，在月经液中到达腹膜腔的增生上皮细胞中CXCR 4蛋白的过表达及其被CXCL 12的不规则激活刺激增殖、侵袭和血管生成，导致病变建立。为了检验这些假设，首先将在子宫内膜和子宫内膜异位细胞的背景下评估CXCR 4-CXCL 12轴在诱导增殖以及侵袭/迁移机制中的功能性（具体目标#1）。接下来，将确定在这些细胞环境中由CXCL 12结合CXCR 4激活的分子机制（具体目标#2）。在具体目标#3中，将使用经充分验证的子宫内膜异位症大鼠模型在体内评估CXCR 4抑制剂CTCE-9908在预防子宫内膜异位症发展中的功效。我们推测增生组织中的基质细胞以旁分泌的方式产生CXCL 12，从而产生诱导表达CXCR 4的上皮细胞存活的微环境。从该项目中获得的知识对于了解子宫内膜细胞如何能够在异位部位增殖，侵入和存活以及炎症反应如何提供适当的细胞环境以诱导异位部位的子宫内膜细胞存活非常重要。此外，这些研究将为针对CXCR 4-CXCL 12轴的这种无法治愈的疾病的未来治疗方式的开发提供见解。 公共卫生相关性：子宫内膜异位症影响数百万妇女在其生殖生命造成疼痛和不孕。没有治愈方法，治疗方法有限。这种疾病的特征是盆腔部位的炎症。这项研究将调查炎症分子CXCR 4在子宫内膜异位症发展中的作用，以及阻断其作用是否可以代表这种疾病的新疗法。

DESCRIPTION (provided by applicant): Endometriosis, like cancer, has also been shown to be characterized by increased proliferation, invasion and angiogenesis; however, the specific mechanisms underlying this estrogen-dependent, invasive disease are still unknown. The two main cellular components of the endometrium, namely epithelial (EEC) and stromal (HESC) cells, show a differential expression of CXCR4 and CXCL12 proteins: endometrial epithelial cells express higher CXCR4 levels than stromal cells; conversely, endometrial stromal cells expressed higher levels of CXCL12 as previously reported from others and our laboratory. Also, we showed that CXCR4 expression is differentially regulated by estradiol (E2) and progesterone (P4) in endometrial cell lines. Finally, we have also shown that CXCR4 is significantly overexpressed in the lesions of the rat model of endometriosis as well as in human endometriotic tissues. The expression of CXCR4 protein in the endometriotic lesions was significantly higher compared to secretory control endometrium, which expresses the highest expression of this chemokine receptor. Based on these preliminary observations, we hypothesize that activation of the CXCR4-CXCL12 axis is a key step in the development and progression of endometriosis. Specifically, this proposal aims to investigate the role of CXCR4 signaling induced by its ligand, CXCL12, in promoting cell proliferation, invasion, and angiogenesis in endometriosis. The main hypothesis driving this proposal is that overexpression of CXCR4 protein in endometriotic epithelial cells reaching the peritoneal cavity in the menstrual fluid, and its unchartered activation by CXCL12, stimulates proliferation, invasion, and angiogenesis leading to lesion establishment. To test these hypotheses, first the functionality of the CXCR4-CXCL12 axis in inducing proliferation as well as invasion/migration mechanisms will be assessed in the context of endometrial and endometriotic cells (Specific Aim #1). Next, the molecular mechanisms activated by CXCL12 binding to CXCR4 in these cellular contexts will be determined (Specific Aim #2). In Specific Aim #3, the efficacy of the CXCR4 inhibitor CTCE-9908 in preventing the development of endometriosis will be assessed in vivo using a well-validated rat model of endometriosis. We speculate that stromal cells in the endometriotic tissue produce CXCL12 in a paracrine manner, thus creating a microenvironment inducive to survival of CXCR4-expressing epithelial cells. The knowledge that will be gained from this project is important to understand how endometrial cells are able to proliferate, invade and survive in ectopic sites and how the inflammatory reaction can provide the appropriate cell environment to induce endometrial cell survival at ectopic locations. Also, these studies will provide insights fo the development of future therapeutic modalities for this incurable condition targeting the CXCR4-CXCL12 axis. PUBLIC HEALTH RELEVANCE: Endometriosis affects millions of women during their reproductive life causing pain and infertility. No cure is available, and treatments are limited. This disease is characterized by inflammation in the pelvic area. This study will investigate the role of an inflammatory molecule, CXCR4, in the development of endometriosis and whether blocking its action could represent a novel treatment for this disease.