环状RNA circ_0006633调控骨肉瘤肿瘤干细胞特性的分子机制研究

Cancer stem cells with the ability of self-renewal and multi-directional differentiation are considered to be the source of cancer recurrence and metastasis. However, the function and mechanism of circRNA on cancer stem cells is unclear. In our previous study, we analyzed the circRNA associated with osteosarcoma stem cells by high-throughput RNA sequencing, and screened out the circRNA circ_0006633.In the present project, based on the previous research of osteosarcoma stem cells and circRNA, we will study effect of circ_0006633 on self-renewal, invasion and metastasis of osteosarcoma stem cells.Then we will investigate the molecular and regulation mechanism of circ_0006633 in osteosarcoma stem cells. Moreover, we will analyze the relationship between circ_0006633 and clinicopathologic features of osteosarcoma, and explore the role of circ_0006633 in the development and progression of osteosarcoma, which would provide new ideas for the diagnosis and treatment of osteosarcoma.

肿瘤干细胞具有自我更新和多向分化能力，被认为是肿瘤复发转移的根源，但是环状RNA在肿瘤干细胞中的功能和机制目前尚不清楚。我们前期通过高通量RNA测序分析了骨肉瘤干细胞相关的环状RNA,从中筛选出环状RNA circ_0006633进行了初步研究。我们拟在对骨肉瘤干细胞和环状RNA前期研究的基础上，深入研究circ_0006633与骨肉瘤干细胞自我更新、侵袭、转移潜能的关系，探索circ_0006633在骨肉瘤干细胞中发挥功能的分子机制和表达调控机制，分析circ_0006633与骨肉瘤临床病理特征的关系及其临床意义，揭示circ_0006633在骨肉瘤发生发展过程中所起的作用，为骨肉瘤的诊断治疗提供新的思路。

本项目通过高通量RNA测序分析了CD24+骨肉瘤干细胞与普通骨肉瘤细胞的差异表达环状RNA，通过验证及筛选选定circ_0006633进一步研究。circ_0006633是由蛋白编码基因FGGY的第3, 4和5外显子环化形成，其在CD24+骨肉瘤细胞和组织中表达量降低。circ_0006633 在CD24+骨肉瘤细胞中主要稳定存在于细胞浆。下调circ_0006633表达后，CD24+骨肉瘤细胞的增殖、转移侵袭能力明显增加。我们通过shRNA下调 circ_0006633 表达后又进行了高通量RNA测序，分析了变化的mRNA情况，并分析了相关的信号通路变化，发现circ_0006633 与KRAS、NOTCH和Wnt信号通路相关，项目组对circ_0006633发挥功能的分子机制及其表达调控机制做深入研究，阐明了circ_0006633在CD24+骨肉瘤干细胞自我更新中所起的作用，为骨肉瘤的诊断和治疗提供新的视角和方向。