Plumbagin Induces Cytotoxicity via Loss of Mitochondrial Membrane Potential and Caspase Activation in Metastatic Retinoblastoma.

ABSTRACT

BACKGROUND/AIM: We investigated the cytotoxic effects of plumbagin on metastatic retinoblastoma, using the highly metastatic cell line Y79. MATERIALS AND METHODS: Effect of plumbagin on cell growth was assessed with water-soluble tetrazolium 1 (WST-1) cell proliferation assay and automated hemocytometry with trypan blue-exclusion assay. Cell death was studied with acridine orange/ethidium bromide live-dead assay and annexin-V-fluorescein isothiocyanate/propidium iodide microscopy. Loss of mitochondrial membrane potential was studied with JC-10 dye and caspase activation was investigated using CellEvent Caspase-3/7 Green detection reagent. RESULTS: Plumbagin highly significantly reduced the growth of Y79 cells treated for 24 h with 2.5 µM or more. Plumbagin also induced significantly high levels of cell death which was associated with loss of mitochondrial membrane potential and caspase activation. CONCLUSION: At very low concentration (2.5 µM), plumbagin potently induced cytotoxicity in metastatic retinoblastoma cells via loss of mitochondrial membrane potential and caspase activation.