The following primary antibodies were used for Western blotting or immunofluorescence studies: rabbit polyclonal antibody against phosphorylated Smad 1/5/8 (1:1000 Western blotting, 1:50 immunofluorescence; Cell Signaling Technologies, Danvers, MA); rat monoclonal antibody against Ki67 (1:100 immunofluorescence; Dako, Carpinteria, CA); goat polyclonal antibody against nestin (1:1000 Western blotting, 1:40 immunofluorescence; R&D Systems, Minneapolis, MN); rabbit polyclonal antibody against poly (ADP-ribose) polymerase-1 (PARP-1; 1:200 Western blotting, 1:50 immunofluorescence; Novus Biologicals Inc., Boulder, CO); mouse monoclonal antibody against β-actin (1:5000 Western blotting; Sigma, St. Louis, MO); rabbit polyclonal antibody against α-smooth muscle actin (1:100 immunofluorescence; Abcam Inc., Cambridge, MA); and rat monoclonal antibody against lysosome-associated membrane protein-1 (LAMP-1, also known as CD107a; 1:200 Western blotting, 1:100 immunofluorescence) and rabbit polyclonal antibody against microtubule-associated protein 1 light chain 3 (MAP LC3; 1:50 immunofluorescence; Santa Cruz Biotechnology, Santa Cruz, CA). All secondary antibodies were from Invitrogen and were conjugated to Alexa Fluor 488 and Alexa Fluor 594 for immunofluorescence studies or to Alexa Fluor 680 and Alexa Fluor 800 for Western blotting studies.