Effects of small interfering (si)RNA hits on transforming growth factor (TGF)-β signaling validated by various methods. (A) Immunodetection of receptor-phosphorylated SMAD2 in extracts of HaCaT cells transfected with the indicated siRNAs and treated with 100 pmol/l TGF-β for 30 minutes. Numbers represent ranked siRNA hits. (B) Effect of siRNA hits on TGF-β-mediated induction of endogenous gene responses. HaCaT cells were incubated with or without 100 pmol/l TGF-β for 3 hours before harvest. Quantitative PCR analysis was used to determine changes of mRNA levels of indicated genes. The mean ± SD of three experiments is shown. Integers (for example, 1, 19) label ranked siRNA hits.