MiR-221 knockdown could sensitize 231T cells to TRAIL, reverse EMT and reduce cell mobility.

<p><b>A</b>. Cultured 231T-n and 231T-si221 cells with different concentrations of TRAIL in 96-well plates. 48 hours later examined their sensitivity to TRAIL by MTT assay. Points represented the average of three independent experiments. Bars stood for SD; <b>B</b>. The mesenchymal markers, N-cadherin, fibronectin, vimentin and Snail expressed in 231T-n and 231T-si221 cells were detected by western blot assay. β-actin was used as control; <b>C</b>. Migration and invasion assay of 231T-n cells and 231T-si221 cells. Staining the migrated cells with hematoxylin–eosin and count them in 10 representative fields under a light microscope. <b>D</b>. Summary graphs for migration and invasion were also shown, respectively. Data was presented as mean ± SD. *P<0.05; **P<0.01.