观察环状RNA线粒体tRNA翻译优化1（circMTO1）在人类肿瘤中的预后价值。我们搜索了多个数据库，查找截至2021年11月01日发表的相关报告。提取OR/HR和95% CI以探索circMTO1表达与各种癌症临床病理特征之间的相关性。通过敏感性分析估计了荟萃分析结果的稳定性。我们采用Begg漏斗图和Egger检验评估出版偏差的潜在影响。还进行了总生存期（OS）的亚组分析。共包括1383例患者的11项研究和包括536例患者的4篇文章。我们发现circMTO1低表达状态与大肿瘤大小（OR = 2.11，95% CI：1.26-3.56，P<0.05）、低分化肿瘤（OR = 2.09，95% CI：1.46-2.98，P<0.05）、肿瘤的OS（HR = 2.02，95% CI：1.63-2.50，P<0.05）和DFS（HR = 1.83，95% CI：1.27-2.56，P<0.05）相关。亚组分析表明，在分析方法、截止值、案例数和NOS评分不同的情况下，circMTO1低表达状态均与OS相关。circMTO1的低表达可能预测大肿瘤大小、低分化和更差的癌症预后，表明circMTO1可能是肿瘤预后的有用生物标记物。

To observe the prognostic value of circular RNA mitochondrial tRNA translation optimization 1 (circMTO1) in human tumors.We searched multiple databases for related reports published before November 01, 2021. The OR/HR and 95% CI were extracted to explore the correlation between circMTO1 expression and clinicopathological features in various cancers. The stability of the results from meta-analysis was estimated via sensitivity analysis. We adopted Begg's funnel plots and Egger's test to appraise the potential bias of publication. Subgroup analysis for overall survival (OS) were also performed.11 studies containing 1383 patients and 4 articles including 536 patients were enrolled. We found that low expression status of circMTO1 was significantly related to big tumor size (OR=2.11, 95% CI: 1.26-3.56, P<0.05), poor differentiation tumors (OR=2.09, 95% CI: 1.46-2.98, P<0.05), OS (HR=2.02, 95% CI: 1.63-2.50, P<0.05), disease-free survival (DFS) (HR=1.83, 95% CI: 1.27-2.56, P<0.05) of cancers. Subgroup analysis indicated that low expression status of circMTO1 was correlated with OS, regardless of analysis method, cut-off value, case number and NOS score.The low expression of circMTO1 may predict big tumor size, poor differentiation and worse outcome of cancer, presenting that circMTO1 may be a useful biomarker for prognosis of tumors.