Ketoconazole potentiates the antitumor effects of nocodazole: In vivo therapy for human tumor xenografts in nude mice.
Our previous studies demonstrated that the oral antifungal agent ketoconazole (KT) induces apoptosis and G0/G1 phase cell cycle arrest in human cancer cell lines. In this study, we first demonstrated that KT (1 microM) potentiated the apoptotic effects of nocodazole (ND, 1 nM) in COLO 205 cancer cells. We further demonstrated the therapeutic efficacy of a combined treatment of KT (50 mg/kg/three times per week) and ND (5 mg/kg/three times per week) in vivo by treating athymic mice bearing COLO 205 tumor xenografts. The antitumor effects of ND were significantly potentiated by KT in mice after 6 wk of treatment. No gross signs of toxicity were observed in mice receiving these treatment regimens. The apoptotic cells were detected in a microscopic view of the terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling staining and by observation of DNA fragmentation in KT + ND-treated tumor tissues. The levels of cell cycle regulatory proteins were determined by Western blot analysis. Treatment with KT inhibits tumor growth through elevation of p53, p21/CIP1, and p27/KIP1 as well as inhibition of cyclin D3 and cyclin-dependent kinase 4 protein expression. Immunohistochemical staining analysis showed that p53, p21/CIP1, and p27/KIP1 immunoreactivity were induced in the tumor tissues. To clarify the roles of the p21/CIP1 and p27/KIP1 protein expression involved in G(0)/G(1) arrest and/or apoptosis induced by a combined treatment with KT and ND, antisense oligodeoxynucleotides (ODNs) specific to p21/CIP1 and p27/KIP1 were used. Our results demonstrated that apoptotic phenomena, including BAX induction and cytochrome C released from mitochondria induced by KT + ND, were significantly attenuated by pretreatment the cells with the p27/KIP1-specific antisense ODNs. These results indicate that p27/KIP1 protein does indeed play a critical role in the KT + ND-induced apoptosis. Our study revealed the molecular mechanism of KT + ND in regression of the tumor growth. The apoptotic effects of KT in a great variety of cancer cells make it a very attractive agent for cancer chemotherapy.
Wang
Ying-Jan
YJ
Department of Environmental and Occupational Health, National Cheng Kung University Medical College, Tainan, Taiwan.
Jeng
Jiiang-Huei
JH
Chen
Rong-Jane
RJ
Tseng
How
H
Chen
Li-Ching
LC
Liang
Yu-Chih
YC
Lin
Chien-Huang
CH
Chen
Chien-Ho
CH
Chu
Jan-Show
JS
Ho
Wei-Lu
WL
Ho
Yuan-Soon
YS
D000230:Adenocarcinoma / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology; D000818:Animals; D000935:Antifungal Agents / Q000494:pharmacology*; D000970:Antineoplastic Agents / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D002352:Carrier Proteins / Q000187:drug effects / Q000378:metabolism; D003110:Colonic Neoplasms / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology; D056743:Cyclin D3; D051358:Cyclin-Dependent Kinase 4; D050759:Cyclin-Dependent Kinase Inhibitor p21; D050760:Cyclin-Dependent Kinase Inhibitor p27; D018844:Cyclin-Dependent Kinases / Q000187:drug effects / Q000378:metabolism; D016213:Cyclins / Q000187:drug effects / Q000378:metabolism; D003574:Cytochrome c Group / Q000187:drug effects / Q000378:metabolism; D004357:Drug Synergism; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D007654:Ketoconazole / Q000494:pharmacology*; D051379:Mice; D008819:Mice, Nude; D015739:Nocodazole / Q000494:pharmacology*; D011518:Proto-Oncogene Proteins / Q000187:drug effects / Q000378:metabolism; D019253:Proto-Oncogene Proteins c-bcl-2; D016159:Tumor Suppressor Protein p53 / Q000187:drug effects / Q000378:metabolism; D023041:Xenograft Model Antitumor Assays; D051028:bcl-2-Associated X Protein
D000935:Antifungal Agents; D000970:Antineoplastic Agents; C494826:BAX protein, human; C494827:Bax protein, mouse; C534696:CCND3 protein, human; C493956:CDKN1A protein, human; C436291:CDKN1B protein, human; D002352:Carrier Proteins; C534697:Ccnd3 protein, mouse; C493957:Cdkn1a protein, mouse; D056743:Cyclin D3; D050759:Cyclin-Dependent Kinase Inhibitor p21; D016213:Cyclins; D003574:Cytochrome c Group; D047908:Intracellular Signaling Peptides and Proteins; D011518:Proto-Oncogene Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D016159:Tumor Suppressor Protein p53; D051028:bcl-2-Associated X Protein; D050760:Cyclin-Dependent Kinase Inhibitor p27; C495900:CDK4 protein, human; C495902:Cdk4 protein, mouse; D051358:Cyclin-Dependent Kinase 4; D018844:Cyclin-Dependent Kinases; D007654:Ketoconazole; D015739:Nocodazole