Molecular Gastroenterology Laboratory, 2nd Department of Internal Medicine, Semmelweis University, Budapest, Hungary; School of PhD Studies, Semmelweis University, Budapest, Hungary.
Department of Cytopathology, National Institute of Oncology, Budapest, Hungary.
Pancreatology. 2019 Sep;19(6):873-879. doi: 10.1016/j.pan.2019.04.001. Epub 2019 Apr 2.
BACKGROUND/OBJECTIVES: Malignant pancreatobiliary strictures are in many cases clinically indistinguishable and present a major problem to endoscopy specialists. Intraductal sampling procedures such as brush cytology are commonly used for diagnosis with a sensitivity that is low for a diagnostic test used in daily clinical practice. MicroRNA (miR) alterations detected in many cancers are disease-specific, which can be utilized in clinical applications. The aim of the present study was to analyze whether determination of miR expression levels in intraductal brush cytology specimens is a feasible approach to improve the diagnosis of pancreatobiliary cancer.
Brush cytology specimens have been collected during endoscopic retrograde cholangio-pancreatography (ERCP) and analyzed by routine cytology and ancillary miR assays. Total RNA was extracted using the miRNeasy Mini Kit and the expression of miRs frequently dysregulated in pancreatobiliary cancer (miR-16, miR-21, miR-196a, miR-221) were analyzed by quantitative real-time PCR using RNU6B as internal control.
Routine cytology resulted in no false positive diagnoses, however, the combined sensitivity remained at 53.8%. Expression (ΔCt values) of miR-16 (p = 0.0039), miR-196a (p = 0.0003) and miR-221 (p = 0.0049) showed a clear statistical significance between malignant and benign pancreatobiliary specimens (n = 35). Malignancy could be detected combining routine cytology and the miR-196a single marker expression levels with a sensitivity of 84.6% (92.9% in biliary strictures) with no false positives.
The results offer the first direct demonstration that microRNAs are readily detectable in brush cytology specimens obtained during ERCP, and have the potential to help the cytological diagnosis of pancreatobiliary malignancy.
背景/目的：恶性胰胆管狭窄在许多情况下临床上难以区分，这对内镜专家来说是一个主要问题。导管内取样程序，如刷取细胞学检查，常用于诊断，但作为日常临床实践中使用的诊断测试，其敏感性较低。许多癌症中检测到的 microRNA（miR）改变是疾病特异性的，可以在临床应用中利用。本研究旨在分析在胆管胰管内镜逆行造影术（ERCP）期间采集的刷取细胞学标本中测定 miR 表达水平是否是改善胰胆管癌诊断的可行方法。
在 ERCP 期间收集刷取细胞学标本，并通过常规细胞学和辅助 miR 检测进行分析。使用 miRNeasy Mini Kit 提取总 RNA，并使用 RNU6B 作为内参，通过定量实时 PCR 分析经常在胰胆管癌中失调的 miRs（miR-16、miR-21、miR-196a、miR-221）的表达。
常规细胞学未导致假阳性诊断，但联合敏感性仍为 53.8%。miR-16（p=0.0039）、miR-196a（p=0.0003）和 miR-221（p=0.0049）的表达（ΔCt 值）在恶性和良性胰胆管标本之间显示出明显的统计学意义（n=35）。将常规细胞学和 miR-196a 单标记表达水平相结合，可以检测到恶性肿瘤，敏感性为 84.6%（胆管狭窄为 92.9%），且无假阳性。
这些结果首次直接证明了 microRNAs 可以在 ERCP 期间获得的刷取细胞学标本中轻易检测到，并且有可能帮助胰胆管恶性肿瘤的细胞学诊断。
