Reducing Claudin 1 protein levels enhanced serum and/or EGF induced A549 cell migration, and Claudin 1 siRNA reduced TNFα-induced morphological changes of A549 cells.

<p>Cells were transfected with Claudin 1 or control siRNA. The confluence monolayers were serum starved, mechanically wounded and then stimulated with serum (10% FBS) and/or EGF (50 ng/ml). The wounded areas at 12 h were quantified. N = 4, Mean ± SEM. *P<0.05 vs. control siRNA treated group. (B). Claudin 1 siRNA clearly reduced Claudin 1 protein levels as shown by Western blotting. (C). Claudin 1 siRNA reduced TNFα- and TNFα plus TGFβ-induced morphological changes as shown by F-actin staining at 48 h. Similar results were also found after 24 h or 72 h of TNFα treatment.