LncRNA HOTAIR enhances ER signaling and confers tamoxifen resistance in breast cancer [array]

HOTAIR is up-regulated in tamoxifen-resistant breast cancer tissues compared to their primary counterparts. Mechanistically, HOTAIR is a direct target of ER-mediated transcriptional repression and is thus restored upon the blockade of ER signaling, either by hormone deprivation or tamoxifen treatment. Lentiviral infected Ctrl or HOTAIR stable MCF7 cells were deprived for 3 days and then treated with ethanol or 1 nM E2 for 6h, cells were collected for RNA extraction.