Figure 1. Curcumin induces apoptosis in melanoma cells.
(A) Annexin V staining of apoptosis in human metastatic melanoma cell lines by flow cytometry following a 48 hour treatment with various doses of curcumin. DMSO (vehicle)-treated cells served as negative controls. Error bars represent the standard deviation from three separate experiments. (B) The pro-apoptotic effects of curcumin were confirmed by immunoblot analysis of PARP cleavage and caspase-3 processing (arrows) in representative metastatic melanoma cell lines following a 24 hour treatment. Membranes were probed with antibodies against β-actin to control for loading. (C) Treatment of the representative A375 and FO1 metastatic melanoma cell lines with curcumin (0 – 20 µM) resulted in decreased levels of basal STAT3 phosphorylation and Bcl-2 protein. Membranes were probed with antibodies against total STAT3 and β-actin protein to control for loading.