Circular RNA (circRNA) is a highly stable, single-stranded, closed-loop RNA that works as RNA or as a protein decoy to regulate gene expression. In humans, thousands of circRNA transcriptional products precisely express in specific developmental stages, tissues and cell types. Due to their stability and specificity, circRNAs are ideal biomarkers for cancer diagnosis and prognosis. To provide an integrated and standardized circRNA expression profile for human cancers, we performed extensive data curation across 11 technical platforms, collecting 48 expression profile data sets for 18 cancer types and amassing 860 751 expression records. We also identified 189 193 differential expression signatures that are significantly different between normal and cancer samples. All the pre-calculated expression analysis results are organized into 132 plain text files for bulk download. Our online interface, circExp, provides data browsing and search functions. For each data set, a dynamic expression heatmap provides a profile overview. Based on the processed data, we found that 52 circRNAs were consistently and differentially expressed in 20 or more processed analyses. By mapping those circRNAs to their parent protein-coding genes, we found that they may have profoundly affected the survival of 10 797 patients in the The Cancer Genome Atlas pan-cancer data set. In sum, we developed circExp and demonstrated that it is useful to identify circRNAs that have potential diagnostic and prognostic significance for a variety of cancer types. In this online and reusable database, found at http://soft.bioinfo-minzhao.org/circexp, we have provided pre-calculated expression data about circRNAs and their parental genes, as well as data browsing and searching functions. Database URL: http://soft.bioinfominzhao.org/circexp/

中文翻译：

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circExp 数据库：癌症中人类 circRNA 表达的在线转录组平台


环状 RNA (circRNA) 是一种高度稳定的单链闭环 RNA，可作为 RNA 或蛋白质诱饵来调节基因表达。在人类中，数千种 circRNA 转录产物在特定的发育阶段、组织和细胞类型中精确表达。由于其稳定性和特异性，circRNA 是癌症诊断和预后的理想生物标志物。为了为人类癌症提供集成且标准化的 circRNA 表达谱，我们在 11 个技术平台上进行了广泛的数据整理，收集了 18 种癌症类型的 48 个表达谱数据集，并积累了 860 751 条表达记录。我们还鉴定了 189 193 个差异表达特征，这些特征在正常样本和癌症样本之间存在显着差异。所有预先计算的表达分析结果被组织成132个纯文本文件以供批量下载。我们的在线界面 circExp 提供数据浏览和搜索功能。对于每个数据集，动态表达式热图提供了概况概述。根据处理后的数据，我们发现 52 个 circRNA 在 20 个或更多处理过的分析中一致且差异表达。通过将这些 circRNA 与其亲本蛋白质编码基因进行比对，我们发现它们可能深刻影响了癌症基因组图谱泛癌数据集中 10797 名患者的生存。总之，我们开发了 circExp 并证明它有助于识别对多种癌症类型具有潜在诊断和预后意义的 circRNA。在这个在线且可重复使用的数据库（http://soft.bioinfo-minzhao.org/circexp）中，我们提供了预先计算的有关circRNA及其亲本基因的表达数据，以及数据浏览和搜索功能。数据库网址：http://soft.生物信息民兆。组织/circexp/