miRNA-200c suppresses CTSL-induced EMT. (A) The effect of CTSL overexpression on A549 cells and the effect of CTSL inhibition on A549/TAX cells. (B) Effect of CTSL overexpression and miRNA-200c mimic in A549 cells and effect of CTSL inhibition and miRNA-200c inhibitor on E-cadherin, N-cadherin, Snail, and vimentin levels in A549/TAX cells were assessed by Western blot analysis. (C) Effects of CTSL overexpression and miRNA-200c mimic in A549 cells and CTSL inhibition and miRNA-200c inhibitor in A549/TAX cells on CTSL, Snail, E-cadherin, N-cadherin, and vimentin levels were subjected to immunofluorescent microscopy. (D) A schematic figure to demonstrate the regulatory link of miRNA-200c, CTSL and EMT. Images were captured using a 63× objective lens. At least three independent experiments were performed.