Knockdown of Smad2 and Smad3 counteracts TGF-β mediated suppression of CXCL1 expression.

<p>(A) 41CAFs and 311NAFs were treated with 5 ng/ml of TGF-β for 24 hours and 48 hours and analyzed for CXCL1 expression by ELISA. (B) 41CAFs were transfected with control siRNA (Con), siRNAs to Smad2 (S2), Smad3 (S3) or both (S2S3), treated with TGF-β for 24 hours, and analyzed for CXCL1 expression by ELISA. (C) 41CAFs transfected with siRNA were treated with TGF-β for 1 hour, and analyzed by western blot for expression of the indicated proteins. Expression levels of Smad2 and Smad3 were normalized to actin through densitometry analysis. Statistical analysis was performed using Two Tailed T-test (A), or One Way ANOVA followed by Bonferonni post-hoc comparisons (B). Statistical significance was determined by p<0.05; *p<0.05, **p<0.01, ***p<0.001, n.s; not significant. Values are expressed as Mean ± SEM.