m6A甲基化作用下的circHOOK3/miR558/ TGFβR1调控轴影响神经母细胞瘤发生、发展的作用机制

The prognosis and treatment effct of neuroblastoma is poor, and the pathogenesis has not been clearly clarified. Recent studies have found the important role of circular RNA in various malignant disorders, however, there is no evidence of the relationship between circular RNA and neuroblastoma. For the first time, we found that the expression of circHOOK3 was significantly reduced in neuroblastoma，and it can bind to the tumor suppressor hsa-miR-558, but the the specific role of circHOOK3 in neuroblastoma and its regulatory mechanisms remain unknown. On this basis, our subject will focus on：whether circHOOK3 act as a ceRNA that competitively binds to hsa-miR-558 , which can relieve the regulation of hsa-miR-558 on the expression of downstream target gene TGFβR1, and the effects of its mechanism on proliferation, invasion, metastasis and angiogenesis of neuroblastoma in vitro and in vivo. Furthermore, we will explore the relationship between m6A and circHOOK3/miR558/ TGFβR1 axis in neuroblastoma. Our subject will firstly elucidate the mechanism of circular RNA expression from the perspective of RNA methylation,and it can provide a new way and solid theoretical foundation for the diagnosis and treatment of neuroblastoma.

神经母细胞瘤预后及治疗效果差，发病机制不清，新近研究发现：环状RNA在多种肿瘤的发生发展中起重要作用，而目前国内外尚无环状RNA与神经母细胞瘤关系的研究。我们首次发现：环状RNA circHOOK3表达在神经母细胞瘤中明显减低，并可与促瘤因子hsa-miR-558结合，但circHOOK3在神经母细胞瘤中的具体作用及调控机制不明。本课题拟在此基础上：观测circHOOK3是否作为ceRNA竞争性结合hsa-miR-558，解除hsa-miR-558对下游靶基因TGFβR1的表达调控；及此种机制对神经母细胞瘤细胞体内外增殖、侵袭、转移及血管生成的影响；并进一步探索在神经母细胞瘤中m6A甲基化与circHOOK3/miR558/ TGFβR1调控轴的关系。本课题从首次RNA甲基化修饰的角度丰富环状RNA的表达调控机理，为神经母细胞瘤的诊治提供新的途径和坚实的理论基础。

神经母细胞瘤预后及治疗效果差，研究发现环状RNA在神经母细胞瘤的发生发展中发挥作用，但具体机制需深入阐明。项目组前期发现hsa-miR-558参与神经母细胞瘤的增殖、侵袭及迁移等，但具体作用机制不明。本项目通过研究证实TGFβR1可影响神经母细胞瘤的疾病进展，且hsa-miR-558可通过与TGFβR1互相作用影响神经母细胞瘤的发展。我们筛选出在神经母细胞瘤中差异表达的环状RNA并进行验证；明确circHOOK3的过表达与神经母细胞瘤细胞株的增殖、侵袭、迁移形成能力显著相关；明确了circHOOK3可通过与hsa-miR-558结合调控其表达水平，并可能通过m6A修饰发挥作用。另一方面，circHOOK3的亲本基因HOOK3与神经母细胞瘤的增殖、侵袭、迁移能力显著相关。我们进一步研究发现，circHOOK3也可能通过m6A修饰调控亲本基因HOOK3的表达水平；我们筛选出HOOK3的下游靶基因PHGDH，并明确HOOK3与PHGDH在神经母细胞瘤组织及细胞中的表达呈负相关，双荧光素酶报告基因系统发现HOOK3可通过与下游靶基因PHGDH的启动子结合调控其转录。项目从m6A RNA甲基化修饰的角度丰富环状RNA的表达调控机理，为神经母细胞瘤的诊治提供新的途径和理论基础。

内容获取失败，请点击重试