Dracorhodin perchlorate induces the apoptosis of glioma cells
Authors: Taifeng Pan
Yongjian Dai
Binjie Zhao
Zhen-Gang Tang
Linghu Meng
Xin Chen
Junjie Luo
Journal: Oncology reports (2016)
Discipline: CLINICAL MEDICINE
Keywords: Dracorhodin perchlorate; apoptosis; glioma cells; cell cycle progression; cell viability
Affiliations: Department of Neurosurgery, Renmin Hospital, Hubei University of Medicine, Shiyan, Hubei 442000, P.R. China.

Abstract:  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. 

Retracted: Yes

PubPeer comments:
 Figs 2B, 4A.  (B) The representative images of western blotting indicated that Dp treatment increased the expression level of p53 and p21 protein, but downregulated the expression of Cdc25A, Cdc2, and P-Cdc2 protein in the U87MG and T98G cells.  (A) The representative images of western blot analysis indicated that Dp treatment resulted in the increase of cytochrome c release, and upregulated the expression levels of Bim and Bax proteins, and concurrently decreased Bcl-2 protein expression in the U87MG and T98G cells. Some bands appear to be repeats. ![file] , 
 Fig 3A.  Dp induces apoptosis in glioma cells. (A) Cellular apoptosis was detected with Annexin V-FITC and propidium iodide (PI) double staining 48 h after the cells were incubated with Dp, and the apoptotic percentages were increased in a dose-dependent manner. ![file] All the panels are rife with repeated areas. ![file] ![file] , 
 Retracted [1 April 2021] .  Following the publication of the above paper, a concerned reader drew to the Editors attention that certain of the western blotting data appeared to have been duplicated, comparing Fig. 2B with Fig. 4A; furthermore, the flow cytometric data panels featured in Fig. 3A appeared to contain repeated patternings of data within those data panels.  After having conducted an independent investigation in the Editorial Office, the Editor of *Oncology Reports* has determined that this paper should be retracted from the Journal on account of a lack of confidence concerning the originality and the authenticity of the data. The authors were asked for an explanation to account for these concerns, but the Editorial Office never received any reply. The Editor regrets any inconvenience that has been caused to the readership of the Journal. ,