The miR-30 family microRNAs confer epithelial phenotype to human pancreatic cells

Epithelial-to-mesenchymal transition is a phenomenon necessary for embryonic development and also seen during certain pathological conditions. We show here for the first time that reduction in miR-30 family microRNAs, is responsible for mesenchymal transition of primary cultures of human pancreatic epithelial cells. We found that miR-30 family microRNAs target mesenchymal gene transcripts and maintain them in a translationally inactive state. Forced depletion using miR-30 family specific anti-miRs leads to mesenchymal transition while ectopic overexpression maintains the epithelial phenotype. We also show that miR-30 family microRNAs increase in abundance during differentiation of pancreatic islet-derived mesenchymal cells into hormone-producing islet-like cell aggregates. Our studies in human adult diseased pancreas also demonstrate that miR-30 family microRNAs are expressed at lower abundance in fibrotic lesions during pancreatitis. Together, our data confirm that miR-30 family microRNAs form a part of the regulatory signaling events involved in cellular response of pancreatic epithelial cells during mesenchymal transition.