Systematic analysis of microRNA expression of RNA extracted from fresh frozen and formalin-fixed paraffin-embedded samples
Systematic analysis of microRNA expression of RNA extracted from fresh frozen and formalin-fixed paraffin-embedded samples
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DOI：
10.1261/rna.642907
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发表时间：
2007-10-01
期刊：
影响因子：
4.5
通讯作者：
Ju, Jingfang
中科院分区：
文献类型：
--
作者：
Xi, Yaguang;Nakajima, Go;Ju, Jingfang
microRNAs（miRNAs）是一类非编码小分子RNA，主要通过与靶mRNA的39个UTR相互作用，在翻译水平上调控基因表达。存档的福尔马林固定石蜡包埋（FFPE）标本代表了生物标志物发现的优秀资源。目前缺乏对miRNAs稳定性的系统分析和使用FFPE样品进行表达分析的优化条件。在这项研究中，使用基于高通量锁核酸的miRNA阵列分析FFPE样品中miRNA的表达。还使用miRNA实时定量逆转录-聚合酶链反应（qRT-PCR）分析来研究福尔马林固定对miRNA稳定性的影响。存档的结直肠癌FFPE标本的miRNA的稳定性用可追溯至10年的样品表征。我们的结果显示，1 μ g新鲜冷冻样本和1-5 μ g FFPE样本之间的miRNAs表达谱具有良好的相关性（相关系数R-2 = 0.86-0.89）。基于实时qRT-PCR分析，不同的福尔马林固定时间没有改变miRNA的稳定性。40例结直肠癌FFPE标本中代表性miRNA的表达差异无统计学意义。这项研究为使用FFPE样本在癌症和其他类型疾病中进行miRNA研究提供了基础。
microRNAs (miRNAs) are noncoding small RNAs that regulate gene expression at the translational level by mainly interacting with 39 UTRs of their target mRNAs. Archived formalin-fixed paraffin-embedded (FFPE) specimens represent excellent resources for biomarker discovery. Currently there is a lack of systematic analysis on the stability of miRNAs and optimized conditions for expression analysis using FFPE samples. In this study, the expression of miRNAs from FFPE samples was analyzed using high-throughput locked nucleic acid-based miRNA arrays. The effect of formalin fixation on the stability of miRNAs was also investigated using miRNA real-time quantitative reverse transcription-polymerase chain reaction (qRT-PCR) analysis. The stability of miRNAs of archived colorectal cancer FFPE specimens was characterized with samples dating back up to 10 yr. Our results showed that the expression profiles of miRNAs were in good correlation between 1 mu g of fresh frozen and 1-5 mu g of FFPE samples (correlation coefficient R-2 = 0.86-0.89). Different formalin fixation times did not change the stability of miRNAs based on real-time qRT-PCR analysis. There are no significant differences of representative miRNA expression among 40 colorectal cancer FFPE specimens. This study provides a foundation for miRNA investigation using FFPE samples in cancer and other types of diseases.