The Dysregulation of MicroRNA Machinery Components in Papillary Thyroid Cancer

Abstract

Although various research papers have revealed that alterations of microRNAs (miRNAs) expression profiles in thyroid cancer, there have been few studies on the miRNA machinery itself. Altered expression of microRNA (miRNA) machinery components may play an important role in progression of thyroid cancer. The purposes of this study were to evaluate the mRNA expression levels of important miRNA machinery components in papillary thyroid cancer (PTC) and to investigate the correlations between each component. By using quantitative real-time PCR, the mRNA expressions of the four miRNA machinery components were examined in 40 PTC tissues and their adjacent non-neoplastic tissues. In the present study, decreased mRNA expression level of Drosha was observed in PTC. The altered mRNA expression levels of Dicer and AGO2; DGCR8 and Drosha; AGO2 and DGCR8 were positively correlated with each other. This study revealed for the first time that altered expression of Drosha is present in PTC tissue and could be potentially responsible for altered miRNAs profiles observed in this malignancy.