Fig. 3.
ATF3 promotes cell motility. (A,B) MCF10CA1a cells stably expressing control (shCtrl) or ATF3 (shATF3) shRNA were analyzed by the Boyden chamber migration assay in the presence or absence of 2.5 ng/ml TGFβ (A; *P<0.05, derived from three experiments). ATF3 protein levels were determined by immunoblot (B; a representative of three experiments). (C) MCF10CA1a cells ectopically expressing SMAD3 were transfected with control siRNAs (−) or siRNAs to knockdown ATF3 (+) for 72 hours, followed by a cell motility assay. Migration of cells without ectopic expression of SMAD3 was arbitrarily defined as 1 (*P<0.05). (D) As in C, except that ATF3-expressing cells were used and SMAD2/3 was knocked down (*P<0.05).