As a peripheral blood biomarker, the crucial role of long non-coding RNA (lncRNA) HOTAIR has recently been suggested in many types of disorder. Among these reports, few investigations have indicated overexpression of HOTAIR transcript in the breast cancer patients' peripheral blood. In this regard, we studied the potential impact of radiotherapy on the peripheral blood HOTAIR expression of different breast cancer patients. Curiously, no significant expression level of HOTAIR was determined in the breast cancer patients' peripheral blood, before and after radiotherapy (10 Gy exposure). Deliberating these investigations raised some debates on the specificity of the utilized methods, the corresponding obtained findings and impact of HOTAIR expression on breast cancer predication, as a potential peripheral blood biomarker, which is discussed in this article.
Keywords: Biomarker; Breast cancer patients; HOTAIR expression level; Peripheral blood.