To assess the association of the nucleic acid binding protein yb-1 with mature microRNAs levels in breast cancer. To do this we performed YB-1 siRNA treatement in triplicates alongside an siRNA control Two breast cancer cell-lines, representative of Luminal A and Basal molecular subtypes were used, MCF7 and MDA-MB-435S. Overall design: Two cell-lines, treated with either siYB-1 or si-Ctrl in triplicate samples.