Oridonin triggers apoptosis in colorectal carcinoma cells and suppression of microRNA-32 expression augments oridonin-mediated apoptotic effects
Authors: Hai Jiang
Bo Yang
Jie Yang
Xiaolin Dong
Bin Xiao
Lijun Zhao
Guihua Qiu
Dongling Hu
Chunyu Wang
Journal: Biomedicine & Pharmacotherapy (2015)
Discipline: PHARMACOLOGY & TOXICOLOGY
Keywords: Apoptosis; Caspase-3; Caspase-9; Colorectal carcinoma cells; MicroRNA-32
Affiliations: Department of Medical Care Center, Renmin Hospital, Hubei University of Medicine, Shiyan 442000, Hubei Province, China., Department of Cardiothoracic Surgery, Renmin Hospital, Hubei University of Medicine, Shiyan 442000, Hubei Province, China., Ultrasonic Imaging Division, Renmin Hospital, Hubei University of Medicine, Shiyan 442000, Hubei Province, China., Ultrasonic Imaging Division, Renmin Hospital, Hubei University of Medicine, Shiyan 442000, Hubei Province, China. Electronic address: .

Abstract:  Oridonin, a bioactive diterpenoid isolated from Rabdosia rubescens, has been found to exhibit various anti-tumor effects. In this work, to investigate its pharmacological effects on human colorectal carcinoma HCT-116 and LoVo cells, cell proliferation and apoptosis were respectively evaluated by 3-[4,5-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide (MTT) assay, annexin V-FITC, and propidium iodide (PI) staining. Western blotting was used to detect the expression levels of Bim, Bax, Bcl-2, cytosolic cytochrome c, procaspase-9, cleaved caspase-9, procaspase-3, and caspase-3 proteins. Caspase-Glo-9 and Caspase-Glo-3 assays were applied to determine caspase-9 and caspase-3 activity. MicroRNA-32 (miR-32) expression level was detected by real-time quantitative reverse transcription-polymerase chain reaction (qRT-PCR). The in vivo anti-tumor effects of oridonin were evaluated using cell lines HCT-116 and LoVo xenograft model. The results indicated that oridonin effectively inhibited cell proliferation and induced apoptosis in HCT-116 and LoVo cells in a concentration-dependent manner. Oridonin treatment upregulated the expression levels of Bim, Bax, cytosolic cytochrome c, cleaved caspase-9 and cleaved caspase-3 proteins, downregulated the expression levels of Bcl-2, procaspase-9 and procaspase-3 proteins, and meanwhile obviously activated caspase-9 and caspase-3 in a dose-dependent manner in HCT-116 and LoVo cells. The results of qRT-PCR demonstrated that oridonin treatment significantly decreased miR-32 expression, and furthermore, suppression of miR-32 expression by miR-32 inhibitors augmented oridonin-mediated inhibitory and apoptotic effects in HCT-116 and LoVo cells. In vivo results indicated that oridonin administration through intraperitoneal injection suppressed tumor growth in nude mice. Therefore, these findings suggest that oridonin maybe is a potential candidate for colorectal cancer treatment. 

Retracted: No

PubPeer comments:
 In Fig.2A, the first two panels of  Hela cells and  MCF-7 cells appear to look more similar than expected. Marked in red box. ![file] , 
 The two panel shown in Figure 2A appears to look similar. Marked in blue box Note the different treatments. ![file] , 
 Fig. 5B in this paper and Fig. 4C in another paper by the same group (doi:10.1158 1078-0432.CCR-05-1085). More similar than expected. ![file] ,