HOTAIR and cancer: The role of HOTAIR is well described in cancer where HOTAIR acts as a modular scaffold and interacts directly with PRC2 and LSD1 complexes, recruiting them to target gene loci, and represses their transcription via H3K27-trimethylation (PRC2 complex and EZH2 activity) and H3K4-demethylation (LSD1 activity) (for review [44]).