Division of Nephrology, Department of Internal Medicine, Genome & Biomedical Sciences Building, Room 6312, University of California, Davis, CA 95616, USA.
Biomark Med. 2013 Aug;7(4):623-31. doi: 10.2217/bmm.13.44.
miRNAs are showing utility as biomarkers in urologic disease, however, a rigorous evaluation of their stability in urine is lacking. Here, we evaluate the stability of miRNAs in urine under clinically relevant storage procedures.
MATERIALS & METHODS: Eight healthy individuals provided clean catch urine samples that were stored at room temperature or at 4°C for 5 days, or subjected to ten freeze-thaw cycles at -80°C. For each condition, two miRNAs, miR-16 and miR-21, were quantitated by quantitative real-time PCR.
All conditions demonstrated a surprising degree of stability of miRNAs in the urine: by the end of ten freeze-thaw cycles, 23-37% of the initial amount remained; over the 5-day period of storage at room temperature, 35% of the initial amount remained; and at 4°C, 42-56% of the initial amount remained. Both miRNAs also showed degradation at approximately the same rate.
miRNAs are relatively stable in urine under a variety of storage conditions, which supports their utility as urinary biomarkers.
miRNA 作为泌尿系统疾病的生物标志物具有一定的应用价值，但它们在尿液中的稳定性还需要更严格的评估。本研究旨在评估 miRNA 在临床相关储存条件下在尿液中的稳定性。
8 名健康个体提供了清洁中段尿样本，分别在室温或 4°C 下储存 5 天，或在-80°C 下经历 10 次冻融循环。对于每种条件，通过实时定量 PCR 定量检测 2 个 miRNA（miR-16 和 miR-21）。
所有条件下的 miRNA 在尿液中都表现出惊人的稳定性：经过 10 次冻融循环后，仍有初始量的 23-37%；在室温下储存 5 天，仍有初始量的 35%；在 4°C 下，仍有初始量的 42-56%。这两种 miRNA 的降解速度也大致相同。
miRNA 在各种储存条件下在尿液中相对稳定，这支持了它们作为尿液生物标志物的应用价值。
