PCBP2和miR-151-5p/miR-16共同调节RhoGDIA表达影响神经胶质瘤的转移和侵袭

Until recently, the effect of clinical treatment on malignant gliomas has a poor prognosis and very low survival rates. In-depth study of the regulation mechanism in the occurrence and development of glioma will provide a theoretical basis for the exploration of new drug targets, guiding clinical treatment and prognosis judgement. In recent years, the research on interaction among RNA binding proteins, microRNAs and their target mRNAs has become a hotspot. In our previous work, it was found that a role for the potential proto-oncogene PCBP2 in the growth and survival of gliomas, knockdown of PCBP2 inhibits glioma growth in vitro and in vivo through inhibiting of cell cycle progression and inducing of apoptosis. RhoGDIA was identified as a target mRNA binding to PCBP2 through RIP-chip and biotin pull-down. With bioinformatics analysis, we also found a very close relationship between PCBP2 binding to RhoGDIA-3?UTR and the seed sequence sites of miR-151-5p/miR-16. Based on the previous work, this study will focus on that the cooperative effect of PCBP2 and miR-151-5p/miR-16 on the RhoGDIA-3?UTR modulates the gene expression, furtherly affecting the proliferation, invasion and metastasis of glioma. This work will reveal a new regulatory network on RNA binding proteins, microRNAs and their target mRNAs.

恶性神经胶质瘤在临床上治疗效果、预后差，生存率低。深入研究神经胶质瘤发生和发展过程中调控机制，为开发新药物靶标，指导临床用药及预后判断提供理论基础。近年来RNA结合蛋白、微小RNAs及其靶mRNA之间的相互作用成为研究热点。本项目在前期工作中发现PCBP2作为潜在的原癌基因促进胶质瘤细胞增殖，抑制凋亡。我们利用RIP-chip， pull-down等技术筛选和鉴定了与PCBP2结合的靶mRNA之一-RhoGDIA。通过生物信息学分析，发现与RhoGDIA mRNA 3'UTR区结合的PCBP2和miR-151-5p/miR-16结合位点具有非常密切的空间关系。本项目在上述工作基础上将研究PCBP2和miR-151-5p/miR-16协同作用于RhoGDIA的3'UTR区，调节该基因的表达并进一步影响肿瘤的增殖、浸润和转移。该工作将揭示RNA结合蛋白-微小RNA-mRNA之间新的调控网路。

项目背景：.RNA结合蛋白PCBP2已经在我们的前期实验中被发现在神经胶质瘤中具有原癌样重要作用。通过RIP-Chip技术我们发现RhoGDIA可能作为PCBP2的功能靶基因。RhoGDIA参与胶质瘤的转移和侵袭并且还会受到miR-151-5p和miR-16的共同调节。..本项目的研究内容主要为：.1、检测PCBP2、RhoGDIA和miR-151-5p/miR-16在胶质瘤转移和侵袭中的作用。.2、探索PCBP2和miR-151-5p/miR-16在胶质瘤细胞中对共同靶基因RhoGDIA的调控机制。..重要结果和关键数据为：.1、PCBP2和miR-151-5p/miR-16都可以通过下调RhoGDIA促进胶质瘤细胞的迁移和侵袭。.2、我们还意外发现RhoGDIA与胶质瘤的复发和干性维持呈负相关。.3、RhoGDIA 3'UTR中与PCBP2的结合位点和与miR-151-5p/miR-16的种子序列结合的区域之间形成了一种位点封闭的茎环结构，PCBP2和RhoGDIA 3'UTR的结合可以易化miR-151-5p/miR-16对RhoGDIA的沉默作用。.4、我们还通过RIP-Chip for microRNA技术筛选到包括miR-151-5p在内的一批可以和RNA结合蛋白PCBP2特异结合的microRNAs，同时有103条miRNA，1条前体miRNA和1条核仁小分子RNA可以无细胞选择性地结合PCBP2。..科学意义：.以上这些研究结果不但拓宽了我们对RhoGDIA在胶质瘤中重要作用的认识，还加深了我们对RNA结合蛋白-微小RNA-mRNA之间调控网络的理解。