For the preservation of tissue samples, formalin fixation followed by paraffin embedding (FFPE) has been the method of choice for decades, mainly because it maintains the morphologic characteristics of the original tissue particularly preserved, as well as its genetic material. FFPE cells can be used to perform molecular tests, such as conventional (c) or quantitative (q) reverse transcriptase polymerase chain reaction (RT-PCR), in retrospective investigations. However, extracting RNA from archived FFPE tissues is a challenging procedure, as it requires time and the use of complex extraction methods. As specific FFPE extraction methods are not always available in the laboratories, the objective of this study was to evaluate the performance of a method based on phenol-chloroform (PC) and 2 commercial methods for RNA extraction, adapting their protocols for FFPE tissues. For this study, a pool of FFPE tissues underwent RNA extraction by PC, QIAmp Viral RNA Mini, and RNeasy Mini Kit. Both the RT-cPCR and the RT-qPCR results were favorable, demonstrating the viability of the RNA. As these results expanded the alternatives for low-budget FFPE extraction, the choice of the ideal method to be used will depend on the availability of reagents and kits.

中文翻译：

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克服一切困难

对于组织样本的保存，福尔马林固定后石蜡包埋 (FFPE) 几十年来一直是首选方法，主要是因为它保留了特别保存的原始组织的形态特征及其遗传物质。FFPE 细胞可用于在回顾性研究中进行分子测试，例如常规 (c) 或定量 (q) 逆转录酶聚合酶链反应 (RT-PCR)。然而，从存档的 FFPE 组织中提取 RNA 是一个具有挑战性的过程，因为它需要时间和使用复杂的提取方法。由于特定的 FFPE 提取方法在实验室中并不总是可用，本研究的目的是评估基于苯酚-氯仿 (PC) 的方法和 2 种商业 RNA 提取方法的性能，调整他们的 FFPE 组织方案。在本研究中，一组 FFPE 组织通过 PC、QIAmp Viral RNA Mini 和 RNeasy Mini Kit 进行了 RNA 提取。RT-cPCR 和 RT-qPCR 结果均良好，证明了 RNA 的可行性。由于这些结果扩展了低成本 FFPE 提取的替代方案，因此选择使用的理想方法将取决于试剂和试剂盒的可用性。