Lyngby Janne G, Kristensen Annemarie T, Fredholm Merete, Nielsen Lise N, Cirera Susanna
Department of Veterinary Clinical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
Vet Clin Pathol. 2019 Sep;48(3):455-460. doi: 10.1111/vcp.12757. Epub 2019 Jun 26.
Gastrointestinal (GI) cancer accounts for 14% of feline malignancies. There is a great need for reliable noninvasive diagnostic biomarkers to reach a timely diagnosis and initiate treatment. Fecal microRNAs (miRNAs) could be such a biomarker and have shown great potential in colorectal screening in people but have yet to be investigated in cats.
We aimed to evaluate the presence and stability of feline fecal miRNA under different storage conditions (room temperature [RT], 4, and -20°C) and to evaluate the expression levels of specific fecal miRNAs collected on three separate days (days 1, 4, and 7) in healthy cats.
Healthy cats were prospectively recruited. Fecal samples were collected, aliquoted, and stored for 24 hours at RT and then transferred to -20°C, stored for 24 hours at 4°C and then transferred to -20°C, or were immediately placed at -20°C on day 1 or at -20°C on days 4 and 7 postcollection. Expression of 22 miRNAs was investigated using quantitative real-time PCR.
Ten miRNA assays worked well, and one, let-7b, was used for normalization. No differences in miRNA expression were seen between the three storage temperatures for the nine miRNAs investigated. Only miR-26a showed a significant increase in expression between samples of days 1 and 7. The rest of the miRNAs levels were stable over time.
Fecal miRNA can be isolated from healthy cats. The expression was stable at different temperatures and for most of the miRNAs over time. Prospective studies evaluating fecal miRNA as biomarkers in cats with GI neoplasia are warranted.
胃肠道（GI）癌占猫科动物恶性肿瘤的14%。迫切需要可靠的非侵入性诊断生物标志物来实现及时诊断并开始治疗。粪便微小RNA（miRNA）可能就是这样一种生物标志物，并且在人类的结肠直肠癌筛查中已显示出巨大潜力，但尚未在猫身上进行研究。
我们旨在评估猫粪便miRNA在不同储存条件下（室温[RT]、4℃和-20℃）的存在情况和稳定性，并评估在健康猫中于三个不同日期（第1天、第4天和第7天）收集的特定粪便miRNA的表达水平。
前瞻性招募健康猫。收集粪便样本，进行分装，并在室温下储存24小时，然后转移至-20℃；在4℃下储存24小时，然后转移至-20℃；或者在收集后的第1天立即置于-20℃，或在第4天和第7天置于-20℃。使用定量实时PCR研究22种miRNA的表达。
10种miRNA检测效果良好，其中一种，即let-7b，用于标准化。在所研究的9种miRNA中，三种储存温度之间的miRNA表达未见差异。仅miR-26a在第1天和第7天的样本之间表达有显著增加。其余miRNA水平随时间稳定。
可以从健康猫中分离出粪便miRNA。其表达在不同温度下以及大多数miRNA随时间都是稳定的。有必要进行前瞻性研究以评估粪便miRNA作为猫胃肠道肿瘤生物标志物的作用。
