title: Cinobufagin induces apoptosis of osteosarcoma cells through inactivation of Notch signaling.
abstract: Osteosarcoma (OS) is a major cause of cancer-related mortality in children and young adults worldwide. Due to preexisting or acquired chemoresistance, the current standard neoadjuvant chemotherapy regimens show only moderate activity against OS. In the current study, we explored the potential anti-OS Cinobufagin in vitro and in vivo, and investigated its underlying mechanisms. The antitumor potential of Cinobufagin was assessed using cell viability assays, and cycle and apoptosis were determined. In a cell-based assay, the mRNA and protein expression of Notch-1, Hes-1, Hes-5 and Hey-1 were determined by quantitative polymerase chain reactions and western blotting. The involvement of Notch signaling in Cinobufagin-induced apoptosis was confirmed using gain and loss-of function assays. A xenograft OS model was established and the antitumor effect and biosafety of Cinobufagin were evaluated. Cinobufagin suppressed OS cells growth in a dose- and time-dependent manner, involving both cell cycle arrest at the S phase and programmed cell death. Cinobufagin treatment decreased the expression of Notch-1, and Hes-1, Hes-5 and Hey-1 gene expression in OS cell lines. Furthermore, Notch activation attenuated the Cinobufagin-induced apoptosis, while Notch inhibition enhanced this effect. Using a mouse xenograft model, we found that Cinobufagin inhibited OS cell growth in vivo. The mice showed excellent tolerance to Cinobufagin treatment. Taken together, our data suggested that Cinobufagin inhibited cell survival and induced apoptosis in OS cells both in vitro and in vivo, and these effects were partly mediated through the Notch pathway.
authors.affiliation: Department of Orthopedics, Renmin Hospital of Wuhan University, Wuhan, Hubei, China.
authors.forename: Yongfei
authors.initials: Y
authors.lastname: Cao
authors.affiliation: Department of Orthopedics, Renmin Hospital of Wuhan University, Wuhan, Hubei, China.
authors.forename: Ling
authors.initials: L
authors.lastname: Yu
authors.affiliation: Department of Orthopedics, Renmin Hospital of Wuhan University, Wuhan, Hubei, China.
authors.forename: Guo
authors.initials: G
authors.lastname: Dai
authors.affiliation: Department of Orthopedics, Renmin Hospital of Wuhan University, Wuhan, Hubei, China.
authors.forename: Shanshan
authors.initials: S
authors.lastname: Zhang
authors.affiliation: Department of Orthopedics, Renmin Hospital of Wuhan University, Wuhan, Hubei, China.
authors.forename: Zhengpei
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Carcinogenesis and Translational Research, Ministry of Education, Department of Orthopedic Oncology, Peking University Cancer Hospital & Institute, Beijing, China.
authors.forename: Tian
authors.initials: T
authors.lastname: Gao
authors.affiliation: Department of Orthopedics, Renmin Hospital of Wuhan University, Wuhan, Hubei, China. Electronic address: guoweichun@aliyun.com.
authors.forename: Weichun
authors.initials: W
authors.lastname: Guo
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects*; D002018:Bufanolides / Q000494:pharmacology*; D002453:Cell Cycle / Q000187:drug effects; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D006801:Humans; D008297:Male; D051379:Mice; D012516:Osteosarcoma / Q000473:pathology*; D051880:Receptors, Notch / Q000037:antagonists & inhibitors / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects*; D023041:Xenograft Model Antitumor Assays
chemical_list: D000970:Antineoplastic Agents; D002018:Bufanolides; D051880:Receptors, Notch; C002471:cinobufagin
keywords: Apoptosis; Cinobufagin; Notch signaling pathway; Osteosarcoma