(A) Scratch assay. Representative images of HepT1 cells stably transfected with empty vector control (pIRES) or IGFBP3 migrating into a cell-free wound at 0, 24, and 48 h after wound infliction. Quantitative evaluation of wound closure shows the mean values of three independent experiments. (B) Cell migration and (C) invasion assays. Representative images of HepG2 and HUH7 cells migrating through collagen- (B) or Matrigel-coated (C) transwell plates (pore size, 8 μm) in the presence (IGFBP3) or absence (control) of 1 μg/ml recombinant human IGFBP3. 10% FCS and 50 ng/ml recombinant human HGF served as a chemoattractant in the lower compartment (IGFBP3 and control), whereas a negative control was run without a chemoattractant. The data are the mean ± SEM from three individual experiments. An asterisk indicates P < 0.05.