MicroRNAs in Breast Cancer: A Review

MicroRNAs (miRNAs) are a class of small noncoding RNAs that control gene expression by targeting mRNAs and leading to either translation repression or RNA degradation. Their aberrant expression may be involved in human diseases, including cancer. Breast cancer is the most common cancer among females around the world that is the most prevalent cause of death among females suffering from cancer. Many studies have identified a large number of upregulated oncogenic miRNAs and downregulated tumor-suppressor miRNAs in this type of cancer. In this review, we provide an overview of the biogenesis and role of miRNAs in cancer and summarize the most recent studies focusing on distinctive expression of miRNAs and their potential to be useful as diagnostic and prognostic biomarkers in breast cancer.