Chongqing Key Laboratory of Translational Research for Cancer Metastasis and Individualized Treatment, Chongqing University Cancer Hospital, Chongqing, China (mainland).
Key Laboratory for Biorheological Science and Technology of Ministry of Education (Chongqing University), Chongqing University Cancer Hospital, Chongqing, China (mainland).
Med Sci Monit. 2021 Jan 20;27:e928327. doi: 10.12659/MSM.928327.
BACKGROUND The association between mitochondrial DNA (mtDNA) copy number and head and neck squamous cell carcinoma (HNSCC) risk remains unclear. Therefore, we aimed to evaluate the relationship between mtDNA copy number and HNSCC risk. MATERIAL AND METHODS We searched PubMed, Web of Science, and EMBASE until August 2020. Studies that assessed the association between mtDNA copy number and HNSCC as the outcome of interest were included. We performed a 2-class and dose-response meta-analysis to assess the association between cancer risk and mtDNA. RESULTS Eight articles (2 cohort studies and 6 case-control studies) with a total of 3913 patients were included in our meta-analysis. The overall results showed that mean mtDNA copy number level from 9 studies was 0.71 higher in patients with cancer than in non-cancer controls (the standardized mean differences (SMD) 0.71, 95% CI: 0.28-1.15, P<0.001). However, when 4 studies were pooled by dichotomizing mtDNA copy number at the median value into high- and low-content groups, no significant association between mtDNA content and overall cancer risk was found (odds ratio (OR)=0.87, 95% CI: 0.52-1.44, P=0.584). Furthermore, we observed a non-linear association from 3 studies between increased mtDNA copy number levels (P for nonlinearity <0.001). CONCLUSIONS The elevated mtDNA copy number could predict the risk of HNSCC as a biomarker. Moreover, there was non-linear relationship of risk between HNSCC and mtDNA copy number.
线粒体 DNA（mtDNA）拷贝数与头颈部鳞状细胞癌（HNSCC）风险之间的关系尚不清楚。因此，我们旨在评估 mtDNA 拷贝数与 HNSCC 风险之间的关系。
我们检索了 PubMed、Web of Science 和 EMBASE，检索时间截至 2020 年 8 月。纳入评估 mtDNA 拷贝数作为感兴趣结局与 HNSCC 风险之间关系的研究。我们进行了 2 类和剂量反应荟萃分析，以评估癌症风险与 mtDNA 之间的关系。
共有 8 项研究（2 项队列研究和 6 项病例对照研究）纳入了我们的荟萃分析，共 3913 例患者。总体结果显示，9 项研究中癌症患者的平均 mtDNA 拷贝数水平比非癌症对照组高 0.71（标准化均数差（SMD）0.71，95%CI：0.28-1.15，P<0.001）。然而，当按中位数将 mtDNA 拷贝数分为高含量和低含量组时，4 项研究合并后发现 mtDNA 含量与总体癌症风险之间无显著相关性（比值比（OR）=0.87，95%CI：0.52-1.44，P=0.584）。此外，我们观察到 3 项研究中 mtDNA 拷贝数水平升高与风险之间存在非线性关系（P 非线性<0.001）。
升高的 mtDNA 拷贝数可以作为预测 HNSCC 风险的生物标志物。此外，HNSCC 与 mtDNA 拷贝数之间存在非线性关系。
