SNAI1 and pulmonary fibrosis: During pulmonary fibrosis, the epithelial cells obtain mesenchymal characteristics, including the expression of mesenchymal markers, such as α-smooth muscle actin (α-SMA), vimentin, transcription repressor Snail, and loss of the epithelial cell marker E-cadherin.18, 19 The protein levels of these markers were examined after incubation with TGF-β1 for 72 h under knockdown or knockin lnc-PCF by using immunofluorescence staining and western blot analysis to investigate the effect of lnc-PCF on fibrogenesis.