HOTAIR and cancer: The lncRNA HOX transcript antisense RNA (HOTAIR) was originally discovered by Rinn et al. on chromosome 12q13.13 [20]. HOTAIR targets the PRC2 complex to the HOXD locus and regulates gene expression by delocalizing PRC2, which is a histone H3 lysine 27 methylase associated with gene silencing and cancer progression, and trimethylation of H3K27 [21].