HOTAIR and gastric cancer: We found that various miRNAs may be HOTAIR downstream, and Supplementary Figure S1D shows target genes of six miRNAs, which were significantly enriched downstream of HOTAIR. Next, to investigate whether these miRNAs could be regulated by HOTAIR in gastric cancer cells, we subsequently detected miRNAs in si-HOTAIR-transfected BGC-823 or SGC-7901 cells and found that miR34a expression was upregulated by 4.2-fold compared with control cells (P<0.01, Figures 3a and b).