Epithelial-mesenchymal transition-associated microRNA expression pattern in human biliary tract cancer: a clinical and pathological approach

Introduction: Epithelial-mesenchymal-transition (EMT) is a key mechanism in tumor progression and metastasis which is regulated among others via microRNA-200 (miRNA) family members. Aim: Referring to this, we investigated six miRNAs and their expression pattern in cancer of the biliary tract (BTC) to evaluate their possible role in tumor progression and (de-) differentiation. Methods: Total RNA was isolated from FFPE blocks (n = 34) obtained from surgically resected BTC patients between 1997 and 2013 using the miRNeasy FFPE isolation kit (Qiagen®). Expression levels of six miR-200 family members (miRNA-141, -205…