title: Oridonin triggers apoptosis in colorectal carcinoma cells and suppression of microRNA-32 expression augments oridonin-mediated apoptotic effects.
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.
authors.affiliation: Department of Medical Care Center, Renmin Hospital, Hubei University of Medicine, Shiyan 442000, Hubei Province, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Yang
authors.affiliation: Department of Cardiothoracic Surgery, Renmin Hospital, Hubei University of Medicine, Shiyan 442000, Hubei Province, China.
authors.forename: Hai
authors.initials: H
authors.lastname: Jiang
authors.affiliation: Ultrasonic Imaging Division, Renmin Hospital, Hubei University of Medicine, Shiyan 442000, Hubei Province, China.
authors.forename: Chunyu
authors.initials: C
authors.lastname: Wang
authors.affiliation: Ultrasonic Imaging Division, Renmin Hospital, Hubei University of Medicine, Shiyan 442000, Hubei Province, China.
authors.forename: Bo
authors.initials: B
authors.lastname: Yang
authors.affiliation: Department of Medical Care Center, Renmin Hospital, Hubei University of Medicine, Shiyan 442000, Hubei Province, China.
authors.forename: Lijun
authors.initials: L
authors.lastname: Zhao
authors.affiliation: Department of Medical Care Center, Renmin Hospital, Hubei University of Medicine, Shiyan 442000, Hubei Province, China.
authors.forename: Dongling
authors.initials: D
authors.lastname: Hu
authors.affiliation: Department of Medical Care Center, Renmin Hospital, Hubei University of Medicine, Shiyan 442000, Hubei Province, China.
authors.forename: Guihua
authors.initials: G
authors.lastname: Qiu
authors.affiliation: Department of Medical Care Center, Renmin Hospital, Hubei University of Medicine, Shiyan 442000, Hubei Province, China.
authors.forename: Xiaolin
authors.initials: X
authors.lastname: Dong
authors.affiliation: Ultrasonic Imaging Division, Renmin Hospital, Hubei University of Medicine, Shiyan 442000, Hubei Province, China. Electronic address: xiao_bin168@126.com.
authors.forename: Bin
authors.initials: B
authors.lastname: Xiao
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects* / Q000235:genetics; D051017:Apoptosis Regulatory Proteins / Q000378:metabolism; D000072224:Bcl-2-Like Protein 11; D053148:Caspase 3 / Q000378:metabolism; D053453:Caspase 9 / Q000378:metabolism; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D015179:Colorectal Neoplasms / Q000201:enzymology / Q000235:genetics / Q000473:pathology; D045304:Cytochromes c / Q000378:metabolism; D045786:Diterpenes, Kaurane / Q000737:chemistry / Q000494:pharmacology*; D004789:Enzyme Activation / Q000187:drug effects; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects*; D006801:Humans; D008565:Membrane Proteins / Q000378:metabolism; D051379:Mice; D035683:MicroRNAs / Q000235:genetics* / Q000378:metabolism; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D023041:Xenograft Model Antitumor Assays; D051028:bcl-2-Associated X Protein / Q000378:metabolism
chemical_list: D000970:Antineoplastic Agents; D051017:Apoptosis Regulatory Proteins; C000606775:BCL2L11 protein, human; D000072224:Bcl-2-Like Protein 11; C000606776:Bcl2l11 protein, mouse; D045786:Diterpenes, Kaurane; C568529:MIRN32 microRNA, human; D008565:Membrane Proteins; D035683:MicroRNAs; D011518:Proto-Oncogene Proteins; D051028:bcl-2-Associated X Protein; C011959:oridonin; D045304:Cytochromes c; D053148:Caspase 3; D053453:Caspase 9
keywords: Apoptosis; Caspase-3; Caspase-9; Colorectal carcinoma cells; MicroRNA-32; Oridonin