HOTAIR and ovarian cancer: To examine the effect of inhibiting both HOTAIR and EZH2, we treated a highly platinum-resistant ovarian cancer cell line (A2780_CR5) with dsiRNA targeting HOTAIR and (or) a pharmacological inhibitor of EZH2 (GSK126) and performed survival assays and observed an additive (P < 0.05) on drug sensitivity and survival (Fig. 1A, inhibiting both HOTAIR and EZH2 vs. inhibiting either factor alone).