deparaffinized slides were subjected to antigen retrieval in boiled sodium
citrate buffer solution (pH 6.0) for 10 min, then blocked for 20 min in blocking
buffer (5% bovine serum albumin and 0.01% Triton X-100 in phosphate buffer
solution (PBS; Sigma). After blocking, samples were incubated with rabbit
polyclonal anti-fibronectin (Abcam, ab2413, 1:300) and rabbit polyclonal
anti-integrin β1 (Abcam, ab183666, 1:300) overnight at 4°C. Alexa Fluor 594 goat
anti-rabbit IgG (Life Technologies, USA, 1:500) were used to detect primary
antibodies, and then counterstained with 4′,6-diamidino-2-phenylindole (DAPI;
Invitrogen). Immunofluorescent images were captured using a Leica TCS SP5
confocal microscope (Leica). The expression intensity was measured using the
Image-Pro Plus 6.0 program (Media Cybernetics, Rockville, MD, USA).