miR-101在瘢痕中靶向甲基转移酶EZH2调节Wnt通路拮抗纤维化的分子机制研究

The hypertrophic scar is currently one of the extremely difficult and important problems in the tissue repair and wound healing management, due to its, undefined pathologenetic mechanism, and unsatisfactory outcome in the patients suffering from skin burn or trauma. Screening molecular targets and studying therapeutic strategies would provide new ways for hypertrophic scar treatment. Recently, profile studies of noncoding RNA and methylation regulation have been involved in human fibrosis diseases. However, its expression pattern and underlying mechanisms in the development and progression of hypertrophic have not been elucidated clearly. We have performed microrarray assay to examine the expression levels of miR-101 and EZH2 in the fibroblasts from hypertrophic tissues. By the combinational approaches of bioinformatics and experimental validation, we confirmed the target associations between miR-101 and EZH2. Furthermore, we demonstrated that hypermethylation of SFRP1, a functionally inhibitor of Wnt pathway, is regulated by EZH2. However, the mechanism of miR-101 regulating Wnt pathway, which shows negatively biological function to the TGF-beta1-mediated profibrotic effects, has not been well characterized. This project focuses on the underlying mechanisms of hypertrophic scar, using gene transfection and animal scar model for elucidation of the molecular regulation in miR-101/EZH2/SFRP1 pathway, which induces Wnt to antagonize the TGF-beta1-mediated profibrotic effects. These data will provide novel molecular target for further research both in pathogenic mechanism and clinical therapy.

增生性瘢痕是皮肤损伤后过度纤维化的产物，相关分子机制尚不清楚，临床疗效不确定，为组织修复领域亟待解决的难题之一。非编码RNA和甲基化表观修饰调控纤维增生疾病的重要性逐渐引起关注。我们前期对增生性瘢痕组织进行miRNA表达谱筛选，确认了miR-101调节甲基转移酶EZH2的特异性靶向关系。结合生物数据库中甲基化数据和相应的生物信息学分析，进一步确认了Wnt通路抑制分子SFRP1的高甲基化及活性由EZH2调控。课题组实验证明miR-101对Wnt通路抑制TGF1介导的瘢痕纤维化具有重要调控效应，然而miR101是如何调节影响Wnt通路拮抗纤维化的机制目前尚不清楚。本课题拟以增生性瘢痕为研究对象，主要通过靶基因过表达与siRNA沉默，瘢痕动物模型，研究miR-101/EZH2/SFRP1轴调控Wnt通路拮抗TGFβ1的分子机制。旨在揭示增生性瘢痕病理新机制，为寻找有效治疗途径提供新的分子靶点。

增生性瘢痕是皮肤损伤后过度纤维化的产物，相关分子机制尚不清楚，临床疗效不确定，为组织修复领域亟待解决的难题之一。非编码RNA和甲基化表观修饰调控纤维增生疾病的重要性逐渐引起关注。在课题实施中，我们对增生性瘢痕组织进行miRNA表达谱筛选，确认了miR-101调节甲基转移酶EZH2的特异性靶向关系。结合生物数据库中甲基化数据和相应的生物信息学分析，进一步确认了Wnt通路抑制分子SFRP1的高甲基化及活性由EZH2调控。课题组实验证明miR-101对Wnt通路抑制TGF1介导的瘢痕纤维化具有重要调控效应，发现miR-101是调节影响Wnt通路拮抗纤维化的机制。同时我们拓展性的研究了长链非编码RNA在糖皮质激素拮抗机械张力模型中的作用和机制。该课题对微小RNA和长链RNA的研究，揭示增生性瘢痕病理新机制，找到有效治疗途径提供新的分子靶点。