Hsa_circ_0068515作为竞争性内源RNA在肺鳞癌发生发展中的作用及调控机制

肺鳞癌是世界范围内发病率和死亡率最高的恶性肿瘤之一。环状RNA（circular RNA，circRNA）是一类最新发现的非编码RNA，它参与了多种肿瘤发生发展的调控过程。本项目前期通过对5例肺鳞癌患者癌和癌旁组织样本进行芯片筛选和分析，发现hsa_circ_0068515这一环状RNA分子在肺鳞癌中显著上调且能调控肺鳞癌细胞的增殖。核质分离实验表明该circRNA主要定位在胞浆中，生物信息学预测其对靶基因具有潜在ceRNA调控作用。我们拟进一步通过干扰和过表达实验，在细胞水平研究其对肺鳞癌细胞凋亡、侵袭迁移的影响，并在动物水平上进行验证；通过双荧光素酶报告基因、RNA免疫共沉淀等实验在分子水平检测与该circRNA结合的miRNA，确定其调控机制。结合临床样本，分析该circRNA的表达水平及临床病理因素，确定其是否对肺鳞癌具有临床预后判断价值，以期为肺鳞癌的治疗和预后判断提供实验依据。

Squamous cell carcinoma (SCC) as a type of lung cancer is one of the leading causes of cancer mortality worldwide. Circular RNA (circRNA) is a widely expressed noncoding RNA, which plays a key role in human diseases, especially in cancer. In our previous study, we employed arrays to analyze expression profiles of circRNAs and mRNAs in 5 paired samples of tumorous tissues and adjacent nontumorous tissues from SCC patients, and found that a circRNA molecule, hsa_circ_0068515, was significantly upregulated in SCC. In vitro assays indicated that knockdown of hsa_circ_0068515 by siRNA inhibited the proliferation of SCC cells. Overexpression of hsa_circ_0068515 promoted the proliferation. Bioinformatic analysis indicated that hsa_circ_0068515 had a potential role of competitive endogenous RNA (ceRNA). In this project, we will plan to investigate effects of hsa_circ_0068515 in apoptosis, migration and invasion in SCC cell lines and in nude mice. Using luciferase reporter assay and RNA immunoprecipitation assay (RIP), we will identify miRNAs molecules which are regulated by hsa_circ_0068515. Finally, we will examine the relationship between expression level of hsa_circ_0068515 and cancer progression in clinical samples of SCC. This study may provide novel clues for mechanism of development and progression of lung squamous cell carcinoma and new strategies for clinical treatment.