LncRNA ODRUL/miR-6874-3p/IL-6通路促进骨肉瘤侵袭、转移的作用及机制研究

Osteosarcoma is the most common primary malignant bone tumor in adolescents. Once the lung metastasis occurs, the prognosis is rather poor. However, the treatment target of invasion and metastasis of osteosarcoma remains unclear, hindering the development of osteosarcoma treatment. In the previous study, we screened a new lncRNA ODRUL, highly expressed in resected osteosarcoma tissues and cell lines, which is closely related to the poor prognosis of patients, and found that lncRNA ODRUL plays a role in the invasion and metastasis of osteosarcoma through up-regulating the expression of MMP2. In order to clarify the molecular mechanism of lncRNA ODRUL in promoting the invasion and metastasis of osteosarcoma, by use of microarray screening, bioinformatics analysis, RNA pull-down, and related expression verification at tissue and cell levels, we further found that lncRNA ODRUL could promote the invasion and metastasis of osteosarcoma cells through another two more important target molecules, miR-6874-3p and IL-6 located in the upstream of MMP2. In order to validate this hypothesis, this study aims to further elucidate the role and mechanism of lncRNA ODRUL as an endogenous competitive RNA molecule (ceRNA) in regulation of miR-6874-3p and IL-6 to promote the invasion and metastasis of osteosarcoma in vitro and vivo by using techniques such as gene intervention, RIP and luciferase reporter gene systems. It is expected to provide a potential molecular target for precise treatment of invasion and metastasis of osteosarcoma.

骨肉瘤是青少年最常见的原发恶性骨肿瘤，一旦肺转移，预后极差，其侵袭、转移治疗靶点仍未明确，阻碍了骨肉瘤诊疗的发展。前期我们在骨肉瘤手术标本和细胞系中筛选到高表达的新的LncRNA ODRUL，发现其与预后不良密切相关，并可上调MMP2表达，对骨肉瘤的侵袭转移起一定作用。为明确LncRNA ODRUL促进骨肉瘤侵袭转移的分子机制，我们又通过芯片筛选、生物信息学分析、RNA pull-down及相关组织细胞水平的表达验证，进一步发现LncRNA ODRUL可通过两个更重要的靶分子，miR-6874-3p和MMP2的上游分子IL-6，促进骨肉瘤细胞的侵袭转移。为了验证该假说，本研究拟采用基因干预、RIP及荧光素酶报告基因系统等技术，阐明LncRNA ODRUL作为内源竞争性RNA分子调控miR-6874-3p和IL-6的表达，促进侵袭转移的分子机制，有望为骨肉瘤的精准治疗提供潜在的分子靶标。

骨肉瘤是青少年最常见的原发恶性骨肿瘤，一旦肺转移，预后极差，其侵袭、转移治疗靶点仍未明确，阻碍了骨肉瘤诊疗的发展。在本研究中，基于一系列的细胞分子生物学和动物实验验证，我们进一步明确了 lncRNA ODRUL的靶分子miR-6874-3p在骨肉瘤细胞和组织中明显低表达，与患者的不良预后密切相关，且miR-6874-3p可抑制骨肉瘤细胞的增殖、侵袭、迁移和肿瘤生长，与lncRNA ODRUL的生物学作用相反；进一步的机制研究发现lncRNA ODRUL可在转录后水平，作为竞争内源性RNA，吸附miR-6874-3p，从而解除miR-6874-3p对于IL-6的表达抑制，上调IL-6的表达，进而促进骨肉瘤进展，在骨肉瘤中构建了lncRNA ODRUL/miR-6874-3p/IL-6的调控通路，有望成为骨肉瘤治疗的新的潜在靶点。