Anthocyanins regulate GSK3β, β-catenin and AMPK in vivo and AMPK in vitro . (a) Mice were sacrificed and tumor extracts were subjected to Western blot analysis for quantification of p-GSK3β and β-catenin levels. (b) The level of p-AMPK was also measured by immunohistochemical analysis. (c) Cells were treated with anthocyanins (25–400 μg/ml) for 24 h and total proteins were subjected to Western blot analysis using antibodies against phospho-AMPK and β-actin (loading control). (d) Cells were transiently transfected with AMPK siRNA or non-specific siRNA (control) for 72 h, treated with anthocyanins for 48 h, and assessed for viability using the MTT assay. Cell viability was calculated as a percentage of viable control siRNA-transfected cells.