Oroxylin A induces G2/M phase cell-cycle arrest via inhibiting Cdk7-mediated expression of Cdc2/p34 in human gastric carcinoma BGC-823 cells.

Abstract

We reported previously that oroxylin A, a natural product isolated from Scutellariae Radix, was a potent apoptosis inducer of human hepatoma HepG2 cells. In this study, cell-cycle arrest of BGC-823 human gastric carcinoma cells caused by oroxylin A has been investigated. Based on our 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide (MTT) assay and flow cytometric analysis, treatment of BGC-823 cells with growth suppressive concentrations of oroxylin A caused an irreversible arrest in the G2/M phase of the cell cycle. Western blot analysis demonstrated that oroxylin A-induced cell-cycle arrest in BGC-823 cells was associated with a significant decrease in cdc2/p34, cyclin B1 and cyclin A expression. In addition, oroxylin A-treated cells decreased the expression of Cdk7, which was responsible for the low expression of M phase promoting factor (cyclin B1/Cdc2). The results suggested that oroxylin A induced G2/M phase cell-cycle arrest via inhibiting Cdk7-mediated expression of Cdc2/p34 in human gastric carcinoma BGC-823 cells.

• Authors: Yong Yang, Yang Hu, Hong-Yan Gu, Na Lu, Wei Liu, Qi Qi, Li Zhao, Xiao-Tang Wang, Qi-Dong You, Qing-Long Guo
• Journal: The Journal of pharmacy and pharmacology (J Pharm Pharmacol) Vol. 60 Issue 11 Pg. 1459-63 (Nov 2008) ISSN: 0022-3573 [Print] England
• PMID: 18957166 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Antineoplastic Agents, Phytogenic
• CCNB1 protein, human
• Cyclin A
• Cyclin B
• Cyclin B1
• Flavonoids
• Tetrazolium Salts
• Thiazoles
• 5,7-dihydroxy-6-methoxy-2-phenylchromen-4-one
• CDC2 Protein Kinase
• Cyclin-Dependent Kinases
• thiazolyl blue
• Cyclin-Dependent Kinase-Activating Kinase
• CDK7 protein, human

Topics

• Antineoplastic Agents, Phytogenic (pharmacology)
• Blotting, Western
• CDC2 Protein Kinase (drug effects, metabolism)
• Cell Division (drug effects)
• Cell Line, Tumor
• Cyclin A (drug effects, metabolism)
• Cyclin B (drug effects, metabolism)
• Cyclin B1
• Cyclin-Dependent Kinases (drug effects, metabolism)
• Flavonoids (pharmacology)
• Flow Cytometry
• G2 Phase (drug effects)
• Gene Expression Regulation (drug effects)
• Humans
• Stomach Neoplasms (drug therapy, pathology)
• Tetrazolium Salts
• Thiazoles
• Cyclin-Dependent Kinase-Activating Kinase