Liu Weihai, Zhang Jiajun, Zou Changye, Xie Xianbiao, Wang Yongqian, Wang Bo, Zhao Zhiqiang, Tu Jian, Wang Xiaoshuai, Li Hongyi, Shen Jingnan, Yin Junqiang
Cell Physiol Biochem. 2017;43(3):969-985. doi: 10.1159/000481650. Epub 2017 Sep 29.
BACKGROUND/AIMS: Osteosarcoma (OS) is the most common primary malignant bone tumor in children and adolescents. However, the molecular mechanisms regulating osteosarcoma tumorigenesis and progression are still poorly understood. Circular RNAs (circRNAs) have been identified as microRNA sponges and are involved in many important biological processes. This study aims to investigate the global changes in the expression pattern of circRNAs in osteosarcoma and provide a comprehensive understanding of differentially expressed circRNAs.
Microarray based circRNA expression was determined in osteosarcoma cell lines and compared with hFOB1.19, which was used as the normal control. We confirmed the microarray data by real time-qPCR in both osteosarcoma cell lines and tissues. The circRNA/microRNA/mRNA interaction network was predicted using bioinformatics. Gene Ontology analysis and 4 annotation tools for pathway analysis (KEGG, Biocarta, PANTHER and Reactome) were used to predict the functions of differentially expressed circRNAs.
We revealed a number of differentially expressed circRNAs and 12 of them were confirmed, which suggests a potential role of circRNAs in OS. Among these differentially expressed circRNAs, hsa_circRNA_103801 was up-regulated in both osteosarcoma cell lines and tissues, while hsa_circRNA_104980 was down-regulated. The most likely potential target miRNAs for hsa_circRNA_103801 include hsa-miR-370-3p, hsa-miR-338-3p and hsa-miR-877-3p, while the most potential target miRNAs of hsa_circRNA_104980 consist of hsa-miR-1298-3p and hsa-miR-660-3p. Functional analysis found that hsa_circRNA_103801 was involved in pathways in cancer, such as the HIF-1, VEGF and angiogenesis pathway, the Rap1 signaling pathway and the PI3K-Akt signaling pathway, while hsa_circRNA_104980 was related to some pathways such as the tight junction pathway.
This study has identified the comprehensive expression profile of circRNAs in osteosarcoma for the first time. And the ceRNA network prediction and bioinformatics functional analysis could provide a comprehensive understanding of hsa_circRNA_103801 and hsa_circRNA_104980, which may be involved in the initiation and progression of osteosarcoma. The present study indicates that circRNAs may play important roles in osteosarcoma and thus serve as biomarkers of osteosarcoma diagnosis and treatment.
背景/目的：骨肉瘤（OS）是儿童和青少年中最常见的原发性恶性骨肿瘤。然而，调节骨肉瘤肿瘤发生和进展的分子机制仍知之甚少。环状RNA（circRNAs）已被鉴定为微小RNA海绵，并参与许多重要的生物学过程。本研究旨在调查骨肉瘤中circRNAs表达模式的整体变化，并全面了解差异表达的circRNAs。
通过微阵列测定骨肉瘤细胞系中circRNA的表达，并与用作正常对照的hFOB1.19进行比较。我们通过实时定量PCR在骨肉瘤细胞系和组织中证实了微阵列数据。使用生物信息学预测circRNA/微小RNA/信使RNA相互作用网络。基因本体分析和4种通路分析注释工具（KEGG、Biocarta、PANTHER和Reactome）用于预测差异表达circRNAs的功能。
我们揭示了许多差异表达的circRNAs，其中12个得到了证实，这表明circRNAs在骨肉瘤中具有潜在作用。在这些差异表达的circRNAs中，hsa_circRNA_103801在骨肉瘤细胞系和组织中均上调，而hsa_circRNA_104980下调。hsa_circRNA_103801最可能的潜在靶微小RNA包括hsa-miR-370-3p、hsa-miR-338-3p和hsa-miR-877-3p，而hsa_circRNA_104980最潜在的靶微小RNA包括hsa-miR-1298-3p和hsa-miR-660-3p。功能分析发现，hsa_circRNA_103801参与癌症相关通路，如HIF-1、VEGF和血管生成通路、Rap1信号通路和PI3K-Akt信号通路，而hsa_circRNA_104980与一些通路如紧密连接通路有关。
本研究首次确定了骨肉瘤中circRNAs的全面表达谱。ceRNA网络预测和生物信息学功能分析可以全面了解hsa_circRNA_103801和hsa_circRNA_104980，它们可能参与骨肉瘤的发生和进展。本研究表明，circRNAs可能在骨肉瘤中发挥重要作用，因此可作为骨肉瘤诊断和治疗的生物标志物。
