Eagle’s minimum essential medium (MEM), fetal bovine serum (FBS), and trypsin-EDTA (0.5% trypsin; 5.3 mM EDTA, tetrasodium salt) were obtained from Gibco BRL (Rockville, MD). Acid-solubilized porcine type I collagen (Cellmatrix type I-A; 3 mg/mL) and reconstitution buffer (50 mM NaOH, 260 mM NaHCO3, and 200 mM HEPES [pH 7.3]) were from Nitta Gelatin (Yao, Osaka, Japan). Dulbecco’s phosphate-buffered saline (PBS) was from Nissui Pharmaceutical (Tokyo, Japan), and bovine serum albumin (fraction V; BSA) was from Nacalai Tesque (Kyoto, Japan). Paraformaldehyde, recombinant human platelet-derived growth factor-BB (PDGF-BB), recombinant human basic fibroblast growth factor (bFGF), phorbol 12-myristate 13-acetate (PMA), 4α-phorbol 12-myristate 13-acetate (4α-PMA), 1-(5-isoquinolinesulfonyl)-2-methyl-piperazine (H-7), 1,2-dimethoxy-N-methyl(1,3)benzodioxolo[5,6-c]phenanthridinium chloride (chelerythrine), 3-[1-(dimethylaminopropyl)indol-3-yl]-4-(indol-3-yl)-maleimide (bisindolylmaleimide I), N-(2-guanidinoethyl)-5-isoquinolinesulfonamide (HA1004), l-α-lysophosphatidic acid (LPA), 1-(5-chloronaphthalene-1-sulfonyl)-1H-hexahydro-1,4-diazepine (ML-9), 1-(N,O-bis[5-isoquinolinesulfonyl]-N-methyl-l-tyrosyl)-4-phenylpiperazine (KN-62), and cytochalasin D were obtained from Sigma (St. Louis, MO). Exoenzyme C3 was from Upstate Biotechnology (Lake Placid, NY). Recombinant human TGF-β1 was from R&D Systems (Minneapolis, MN), and recombinant human insulin-like growth factor (IGF)-I and recombinant human epidermal growth factor (EGF) were from Collaborative Biomedical Products (Bedford, MA). Twenty-four–well cell culture clusters and 162-cm2 cell culture flasks were obtained from Corning (Corning, NY), and glass-bottomed dishes were from Matsunami (Kishiwada, Osaka, Japan). Thapsigargin and 2-aminoethoxydiphenylborate (2-APB) were obtained from Calbiochem-Novabiochem (Darmstadt, Germany), and fluorescent phalloidin (Alexa Fluor 568) was from Molecular Probes (Eugene, OR).