Dracorhodin perchlorate induces the apoptosis of glioma cells.

Dracorhodin perchlorate (Dp), a synthetic analogue of the antimicrobial anthocyanin red pigment, has recently been shown to induce apoptotic cell death in various types of cancer cells. Yet, the inhibitory effect of Dp on human glioma cells remains uninvestigated. Therefore, in the present study, 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay and flow cytometry were used to detect cell viability and cell cycle progression in glioma U87MG and T98G cells, respectively. Annexin V-FITC/propidium iodide double staining and JC-1 staining were separately applied to determine cellular apoptosis and mitochondrial membrane potential damage in the cells. The expression levels of associated proteins involved in cell cycle progression and apoptosis were measured by western blotting. The activities of caspase‑9/-3 were determined by Caspase-Glo-9/3 assay. The results indicated that Dp treatment significantly inhibited cell proliferation in a dose- and time-dependent manner, and blocked cell cycle progression at the G1/S phase in the U87MG and T98G cells via the upregulation of p53 and p21 protein expression, and simultaneous downregulation of Cdc25A, Cdc2 and P-Cdc2 protein expression. Additionally, Dp treatment led to the loss of cellular mitochondrial membrane potential, and the release of cytochrome c, and strongly induced the occurence of apoptosis. Increased expression levels of Bim and Bax protein and the downregulated expression of Bcl-2 protein were observed. Caspase-9/-3 were activated and their activities were elevated after Dp treatment. These findings indicate that Dp inhibits cell proliferation, induces cell cycle arrest and apoptosis in glioma cells, and is a possible candidate for glioma treatment.