SIGC were pre-treated with or without vitamin C (1 mM) for 24 h and treated with CrVI (10 μM) for 0 h, 12 h and 24 h period. Western blots were performed with 75 μg of protein, as described in Materials and Methods section. A, Representative western blots of cyclins D1, D2, D3, E2, A, B1, PCNA and b-actin. B, Histograms of Integrated Density Value (IDV) for each protein, normalized toβ-actin. Each value is the mean ± SEM from 3 different plates per treatment, P<0.05; a: CrVI-treatment, 0 h vs 12 h or 24 h; b: Vitamin C vs CrVI+Vitamin C-treatment, 0 h vs 12 h or 24 h; c: CrVI (12 h or 24 h) vs CrVI+Vitamin C (12 h or 24 h).