Tumor heterogeneity and poor outcomes of breast cancer (BC) patients have led researchers to define new markers of disease. In recent years, microRNA expression patterns have proven to be good disease indicators. Levels of miR-203a, in particular, were shown to be altered in different types of cancer. We assessed the relationship between miR-203a expression and clinicopathological features of BC in a Portuguese cohort. The expression levels of miR-203a were analyzed in 109 formalin-fixed paraffin-embedded paired normal and tumor tissue samples.
