Cetuximab potentiates oxaliplatin cytotoxic effect through a defect in NER and DNA replication initiation.
Br J Cancer
; 98(1): 120-8, 2008 Jan 15.
Article
em En
| MEDLINE
| ID: mdl-18182978
ABSTRACT
Preclinical studies have demonstrated that the chemotherapeutic action of oxaliplatin, a third generation platinum derivative, is improved when combined with cetuximab, a monoclonal antibody inhibitor of epidermal growth factor receptors. To explore the mechanism of this synergistic benefit, we used HCT-8 and HCT-116, two human colon cancer cell lines, respectively, responsive and non-responsive to the oxaliplatin/cetuximab combination. We examined the effect of drug exposure on glutathione-S-transferase-mediated oxaliplatin detoxification, DNA-platinum adducts formation, cell cycle distribution, apoptosis, and the expression of multiple targets involved in DNA replication, recombination, and repair. The major changes we found in HCT-8 were a stimulation of oxaliplatin-DNA adduct formation associated with reduced expression of the key enzyme (excision repair cross complementation group1 ERCC1) in the key repair process of oxaliplatin-DNA platinum adduct, the nucleotide excision repair (NER), both at the mRNA and protein levels. We also observed a reduced expression of factors involved in DNA replication initiation, which correlates with an enrichment of cells in the G1 phase of the cell cycle as well as an acceleration of apoptosis. None of these changes occurred in the non-responsive HCT-116 cell that we used as a negative control. These findings support the fact that cetuximab potentiates the oxaliplatin-mediated cytotoxic effect as the result of inhibition of NER and also DNA replication initiation.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Protocolos de Quimioterapia Combinada Antineoplásica
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Reparo do DNA
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Replicação do DNA
Limite:
Humans
Idioma:
En
Revista:
Br J Cancer
Ano de publicação:
2008
Tipo de documento:
Article