Eiríkur Briem, a phd. student at the Biomedidcal center at the University of Iceland will discuss his project and results
Profiling miRNAs in breast epithelial progenitor cells during branching morphogenesis and EMT in 3D culture
D492 is a human breast epithelial cell line with stem cell properties that can generate luminal and myoepithelial cells. When D492 is cultured in 3D reconstituted basement membrane (3D-rBM) it forms branching ducts reminiscent of terminal duct lobular units in the human breast gland. When cultured in vascular-rich environment D492 form increased branching structures with some cells undergoing epithelial to mesenchymal transition (EMT). Here we use D492 and D492M as a model to investigate miRNA expression patterns during different stages of branching and in EMT. We performed small RNA-sequencing on D492 and D492M in 3D cultures. Some of the differentially expressed miRNAs have previously been associated with maintenance of the epithelial phenotype, such as the miRNA 200 family. We have recently shown that miRNA-200c-141 convert D492M back to the epithelial phenotype (Hilmarsdottir et al. Dev Biol 2015). Among the most downregulated miRNAs in D492M is miR-203a, which plays an important role in epithelial development. Here data from small RNA sequencing and profiling of miR-203a in breast progenitor cells will be presented.