环状RNA是近年来发现的一类新型非编码RNA，广泛存在于真核生物转录组中，可通过海绵作用吸附Micro RNA以及和其它生物大分子相互作用在组织发育、肿瘤发生中发挥着重要作用。最新研究发现环状RNA circ-Mbl，circ-FBXW7可翻译功能性蛋白。但其他环状RNA是否翻译对恶性胶质瘤具有关键作用的新蛋白及作用机制尚不明确。申报人发现长链非编码RNA LINC-PINT产生的环状RNA可翻译一个由87个氨基酸组成的新蛋白PINT87aa。其在胶质瘤中的表达较正常组织明显下降，能够在体外抑制胶质瘤细胞的增殖。本项目拟研究：1）探索PINT87aa对胶质瘤细胞的作用方式与临床意义；2）研究PINT87aa抑癌功能的分子机制；3）验证PINT87aa的临床转化前景。通过本项目初步阐明PINT87aa在胶质瘤中的作用机制，拓宽人们对环状RNA翻译功能的认知，为胶质瘤的靶向治疗提供有益的参考。

Circular RNA (circRNA) is a new type of non-coding RNA newly discovered in recent years,and widely exists in eukaryotic transcriptome. It can adsorb MicroRNA like a sponge and interact with other biological macromolecules, which plays an important role in tissue development and tumorigenesis. The latest researchs have found that circRNA circ-Mbl, circ-FBXW7, etc. could translate functional proteins.However, it remains unclear whether other circRNAs could translate new proteins which can play key roles in malignant gliomas. We found that the circular RNA which produced by the long-chain non-coding RNA LINC-PINT can translate a novel protein consisting of 87 amino acids, PINT87aa. Its expression in glioma significantly decreased comparing with normal tissues, and could inhibit the proliferation of glioma cells in vitro. The project is to study: 1) To explore the role of PINT87aa in glioma cells and clinical meaning; 2)To study the molecular mechanisms of PINT87aa tumor suppressing function; 3) To verify the clinical prospects of PINT87aa. The project initially clarified the mechanisms of PINT87aa in glioma and broadened the understanding of the translation function of circular RNA, providing a useful reference for the targeted therapy of human gliomas.