Li Shimeng, Qiao Lu, Yang Zhaowei, He Chengyan
Department of Clinical Laboratory, China-Japan Union Hospital of Jilin University, Changchun, China.
Front Physiol. 2018 Oct 8;9:1407. doi: 10.3389/fphys.2018.01407. eCollection 2018.
Nicotinamide N-methyltransferase (NNMT) is an enzyme that catalyzes N-methylation of pyridine-containing compounds. NNMT is upregulated in many types of solid tumors, suggesting the potential for its use as a tumor biomarker. However, the prognostic value of NNMT in solid tumors is still unclear. We therefore conducted a meta-analysis to investigate the association between NNMT expression and survival in patients with solid tumors. We focused on patients with solid tumors, using high NNMT expression levels as the intervention and low NNMT expression levels as the comparison, according to Patient, Intervention, Comparison, and Outcome (PICO) guidelines. Electronic databases (up to June 7, 2018) were comprehensively searched to collect relevant cohort studies regarding the associations between NNMT expression levels and survival outcomes (overall survival [OS], disease-specific survival [DSS] including cancer-specific survival [CSS], and time to tumor progression [TTP] including disease-free survival [DFS], progression-free survival [PFS], and metastasis-free survival [MeFS]). Publication biases were also examined. All analyses were performed using STATA 12.0 software. A total of 3340 patients with solid tumors from nine published studies were included. The combined hazard ratio (HR) identified high NNMT expression levels as a poor prognostic predictor of OS (HR = 1.67, 95% CI = 1.23-2.26). However, NNMT levels had no significant association with DSS (HR = 1.47, 95% CI = 0.95-2.28) and TTP (HR = 1.13, 95%CI = 0.39-3.25). High NNMT expression levels may be a poor prognostic biomarker for patients with solid tumors.
烟酰胺N-甲基转移酶（NNMT）是一种催化含吡啶化合物N-甲基化的酶。NNMT在多种实体瘤中上调，提示其作为肿瘤生物标志物的潜力。然而，NNMT在实体瘤中的预后价值仍不清楚。因此，我们进行了一项荟萃分析，以研究NNMT表达与实体瘤患者生存之间的关联。根据患者、干预措施、对照和结局（PICO）指南，我们聚焦于实体瘤患者，将高NNMT表达水平作为干预措施，低NNMT表达水平作为对照。全面检索电子数据库（截至2018年6月7日），以收集有关NNMT表达水平与生存结局（总生存[OS]、疾病特异性生存[DSS]，包括癌症特异性生存[CSS]，以及肿瘤进展时间[TTP]，包括无病生存[DFS]、无进展生存[PFS]和无转移生存[MeFS]）之间关联的相关队列研究。还检查了发表偏倚。所有分析均使用STATA 12.0软件进行。纳入了来自9项已发表研究的总共3340例实体瘤患者。合并风险比（HR）确定高NNMT表达水平是OS的不良预后预测指标（HR = 1.67，95%CI = 1.23 - 2.26）。然而，NNMT水平与DSS（HR = 1.47，95%CI = 0.95 - 2.28）和TTP（HR = 1.13，95%CI = 0.39 - 3.25）无显著关联。高NNMT表达水平可能是实体瘤患者的不良预后生物标志物。
