The Role of Long Non-Coding RNAs in Breast Cancer.

Long non-coding RNA (lncRNA) genes are an important population of non-coding RNAs with defined key roles in normal development as well as tumorigenesis process. Evidences suggest that they can be classified as tumor suppressor genes or oncogenes according to their functions and expression pattern in tumoral tissues. They have been shown to regulate the plasticity of cancer stem cells. Their important roles in the regulation of cancer-related pathways in addition to deregulation of their expression in a number of cancers have suggested that they can be used as markers for cancer detection and prognosis, as well as targets for cancer treatment. Deregulation of a number of lncRNAs, such as HOTAIR, XIST, MALAT, and H19 has been detected in breast cancer samples and cell lines. In addition, the association between lncRNAs signature and breast cancer patients' survival has been assessed in various studies. Here, the expression patterns of lncRNAs in breast cancer, as well as their significance in prognosis and patient treatment are discussed.