BACKGROUND Due to the remarkably stable form in the bloodstream, circulating microRNAs (miRNAs) are indicated as promising novel minimally invasive biomarkers in many cancers. However, available data of miRNAs in nasopharyngeal carcinoma (NPC) are relatively limited. METHODS Based on the GEO database and previous published reports, 21 dysregulated miRNAs were selected for screening via microarray analysis (20 NPC samples vs 10 controls). Dysregulated miRNAs were then detected and verified by the method of quantitative reverse transcription-polymerase chain reaction (qRT-PCR) in the training and validation sets. The candidate miR-214-3p was then evaluated in the evaluation set, including the association between miR-214-3p and clinicopathological characteristics, dynamic changes in NPC patients and the predictive value for NPC recurrence or metastasis. RESULTS Seven miRNAs were significantly altered in comparison with healthy controls by microarray analysis. MiR-214-3p was the most significantly expressed in training and validation sets by qRT-PCR. Plasma miR-214-3p expressions were significantly associated with UICC stages and NPC recurrence or metastasis. Plasma miR-214-3p expressions showed a gradual decrease during the follow-up after treatment in NPC patients. Patients with recurrence or metastasis were always accompanied with higher levels of plasma miR-214-3p at the same time point. High pretreatment miR-214-3p expression (≥3.12) was significantly associated with NPC recurrence or metastasis by log-rank test using Kaplan-Meier survival curve analysis (P = 0.006). CONCLUSIONS Circulating miR-214-3p can serve as a noninvasive biomarker for the prediction of recurrence or metastasis in NPC patients.

中文翻译：

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循环的miR-214-3p可预测鼻咽癌的复发或转移。

背景技术由于血液中非常稳定的形式，循环微RNA（miRNA）被认为是许多癌症中有希望的新型微创生物标志物。但是，鼻咽癌（NPC）中miRNA的可用数据相对有限。方法基于GEO数据库和先前发表的报告，通过微阵列分析选择了21个失调的miRNA进行筛选（20个NPC样品与10个对照）。然后通过训练和验证集中的定量逆转录聚合酶链反应（qRT-PCR）方法检测并验证了失调的miRNA。然后在评估集中评估候选miR-214-3p，包括miR-214-3p与临床病理特征之间的关联，鼻咽癌患者的动态变化以及对鼻咽癌复发或转移的预测价值。结果通过微阵列分析，与健康对照相比，七个miRNA发生了显着改变。在qRT-PCR的训练和验证集中，MiR-214-3p的表达最为明显。血浆miR-214-3p表达与UICC分期和NPC复发或转移显着相关。NPC患者在治疗后的随访过程中血浆miR-214-3p表达逐渐降低。复发或转移的患者总是在同一时间点伴有更高水平的血浆miR-214-3p。使用Kaplan-Meier生存曲线分析通过​​log-rank测试，高预处理miR-214-3p表达（≥3.12）与NPC复发或转移显着相关（P = 0.006）。