The AKT and ERK pathways are required for caveolin-1 induction. (A) Blocking AKT activation with Ly294002 decreased caveolin-1 upregulation on protein and (B) mRNA level (p = 0.018). (C) Induction of Collagen 1α1 mRNA, a mesenchymal marker, was completely abolished when AKT signaling was blocked (P < 0.001). (D) Inhibition of ERK activation via the small molecule inhibitor U0126 (U5: 5 μM; U10: 10 μM) culminated in strongly reduced caveolin-1 induction on protein and (E) mRNA level (p < 0.001). (F) ERK affects upregulation of Collagen 1α1 (p < 0.001) for mRNA expression studies, U0126 was used at a conc. of 10 μM.