Its well-established role is that the increased HOTAIR expression is a biomarker of poor prognosis, and it acts as a modular scaffold of histone modification complex PRC2 and LSD1 to regulate the expression of select genes and promote cancer cell metastasis.12, 17, 18 Recently, another significant role of HOTAIR was reported and that targeting HOTAIR led to cancer cell apoptosis. This evidence concerns the gene KDM1A and cancer.