Clinic of Small Animal Medicine, Centre for Clinical Veterinary Medicine, Ludwig Maximilian University, Munich, Germany.
Specialty Practice for Veterinary Pathology von Bomhard and Pfleghaar, Munich, Germany.
Vet Comp Oncol. 2020 Dec;18(4):502-508. doi: 10.1111/vco.12570. Epub 2020 Feb 17.
Intestinal T-cell lymphomas are common in dogs, but histopathological diagnosis remains challenging because of accompanying enteritis with lymphocyte involvement. Invasively taken full-layer biopsies are still required for reliable differentiation. The detection of specific microRNA expression patterns in canine intestinal T-cell lymphoma could provide new possibilities to differ intestinal lymphoma from benign inflammation and could lead to further understanding of lymphomagenesis. The objective of this study was to characterize microRNA expression in distinct groups of formalin-fixed and paraffin-embedded samples from canine intestinal T-cell lymphomas, lymphoplasmacellular enteritis and healthy intestinal tissue. In a preliminary test with two samples per group, total RNA was extracted (RNEasy FFPE Kit, Qiagen), reverse transcribed (miScript II RT Kit, Qiagen) and pre-amplified (miScript PreAmp PCR Kit, Qiagen). We performed comparative quantitative PCR on microRNA PCR Array plates (Qiagen) with pre-fabricated reactions for 183 different mature canine microRNAs. Subsequently, 12 microRNAs with conspicuous expression changes in the lymphoma group were selected and microRNA expression of all samples (n = 8) per group was analysed with individual microRNA assays (miScript Primer Assays, Qiagen) on the reverse transcribed RNA without pre-amplification. Our results revealed lymphoma-specific expression patterns, with down-regulation of the tumour-suppressing microRNAs miR-194, miR-192, miR-141 and miR-203, and up-regulation of oncogenic microRNAs, including microRNAs from the miR-106a~363 cluster. In addition, we detected only slight expression alterations between healthy intestinal tissue and lymphoplasmacellular enteritis cases. We conclude that microRNA expression patterns can be used to separate T-cell lymphomas from healthy tissue and benign inflammatory disorders.
肠道 T 细胞淋巴瘤在犬中较为常见，但由于伴有淋巴细胞浸润的肠炎，其组织病理学诊断仍然具有挑战性。为了进行可靠的鉴别，仍需要进行侵入性全层活检。在犬肠道 T 细胞淋巴瘤中检测到特定的 microRNA 表达模式，为将肠道淋巴瘤与良性炎症区分开来提供了新的可能性，并可能进一步了解淋巴瘤的发生机制。本研究的目的是描述犬肠道 T 细胞淋巴瘤、淋巴浆细胞性肠炎和健康肠道组织的固定石蜡包埋样本中特定 microRNA 表达特征。在每组两个样本的初步测试中，提取总 RNA（RNEasy FFPE 试剂盒，Qiagen），反转录（miScript II RT 试剂盒，Qiagen）并预扩增（miScript PreAmp PCR 试剂盒，Qiagen）。我们在 microRNA PCR 阵列板（Qiagen）上进行了比较定量 PCR，该板具有针对 183 种不同成熟犬 microRNA 的预制反应。随后，选择在淋巴瘤组中表达变化明显的 12 个 microRNA，并使用个体 microRNA 检测（miScript Primer Assays，Qiagen）对每组所有样本（n = 8）的反转录 RNA 进行分析，无需预扩增。我们的结果揭示了淋巴瘤特异性的表达模式，肿瘤抑制 microRNA miR-194、miR-192、miR-141 和 miR-203 的表达下调，以及包括 miR-106a~363 簇中的 microRNA 在内的致癌 microRNA 的表达上调。此外，我们仅在健康肠道组织和淋巴浆细胞性肠炎病例之间检测到轻微的表达改变。我们得出结论，microRNA 表达模式可用于将 T 细胞淋巴瘤与健康组织和良性炎症性疾病区分开来。
