Rofecoxib augments anticancer effects by reversing intrinsic multidrug resistance gene expression in BGC-823 gastric cancer cells.
J Dig Dis
; 11(1): 34-42, 2010 Feb.
Article
en En
| MEDLINE
| ID: mdl-20132429
ABSTRACT
OBJECTIVE:
To investigate combined chemotherapeutic effects of rofecoxib in combination with 5-fluorouracil (5-FU), cisplatin (DDP) and etoposide (VP-16) in vitro, and to explore the potential mechanisms in modulating multidrug resistance (MDR) expression.METHODS:
The BGC-823 gastric cancer cell line was incubated for 48 h with 0.1 micromol/L rofecoxib, 5-FU, DDP and VP-16 (1 microg/mL, 10 microg/mL and 100 microg/mL) alone, and combined with rofecoxib, respectively. Methyl-thiazolyl-tetrazolium and the terminal deoxynucleotidyl transferase-mediated 2'-deoxyuridine 5'-yriphosphate nick-end labeling assays were performed to calculate inhibitory rates and apoptotic index. Middle effects principles (CI values) were used to determine the interaction between rofecoxib and chemotherapeutic agents. Reverse transcription-polymerase chain reaction (RT-PCR) and Western blot analysis were employed to determine expression of MDR1, multidrug resistance-associated protein 1 (MRP1), glutathione S-tranferase-pi (GST-pi) mRNA and protein in gastric cancer cells administered by rofecoxib, respectively.RESULTS:
Both anticancer drugs such as 5-FU, DDP and VP-16 and rofecoxib inhibited the cells' proliferation and induced apoptosis in a dose-dependent manner, and a more significant inhibition was achieved when the cells were co-treated with anticancer drugs and rofecoxib. There was a synergetic role when different concentrations of chemotherapeutic agents were combined with rofecoxib (all CI < 1, P < 0.01 or 0.05). RT-PCR analyses of MDR gene families in BGC-823 gastric cancer cells revealed a strong expression in MRP1 and GST-pi mRNA, but MDR1 mRNA was undetectable. After administration with different concentrations of rofecoxib (0.1, 1.0, 10 micromol/L), significant downregulation of MRP1 and GST-pi mRNA was observed (MRP1 from 0.984 +/- 0.093-0.513 +/- 0.098; GST-pi from 1.078 +/- 0.201-0.472 +/- 0.084, P < 0.01 or 0.05). In addition, MRP1 and GST-pi protein expression induced by rofecoxib were also reduced (P < 0.01 or 0.05).CONCLUSION:
Rofecoxib, a specific cyclooxygenase-2 inhibitor, plays a chemotherapeutic sensitizer role in various anticancer agents on the BGC-823 gastric cancer cell line, which could be partly explained by its ability to reverse the intrinsic MRP1 and GST-piin vitro.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Neoplasias Gástricas
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Sulfonas
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Adenocarcinoma
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Protocolos de Quimioterapia Combinada Antineoplásica
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Regulación de la Expresión Génica
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Inhibidores de la Ciclooxigenasa 2
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Lactonas
Límite:
Humans
Idioma:
En
Revista:
J Dig Dis
Año:
2010
Tipo del documento:
Article
País de afiliación:
China