Display Settings:

Format

Send to:

Choose Destination
We are sorry, but NCBI web applications do not support your browser and may not function properly. More information
Clin Cancer Res. 2005 Sep 1;11(17):6261-9.

Tumor growth inhibition by simultaneously blocking epidermal growth factor receptor and cyclooxygenase-2 in a xenograft model.

Author information

  • 1Winship Cancer Institute, Emory University School of Medicine, Atlanta, Georgia 30322, USA.

Abstract

PURPOSE:

Our previous study revealed that simultaneously targeting epidermal growth factor receptor (EGFR) tyrosine kinase and cyclooxygenase-2 (COX-2) additively or synergistically inhibited growth of squamous cell carcinoma of the head and neck (SCCHN) in vitro. However, an in vivo efficacy of this combined treatment in SCCHN has not been studied.

EXPERIMENTAL DESIGN:

Nude mice were pretreated with control (1% Tween 80), ZD1839 (50 mg/kg) alone, celecoxib (50 mg/kg) alone, or a combination of ZD1839 and celecoxib at the same dosages for 7 days before injection of a human SCCHN cell line Tu212. The animals were continuously treated with the agents 5 days a week for about 11 weeks.

RESULTS:

Tumor growth in the combined treatment was significantly inhibited compared with the control (P < 0.001), ZD1839 (P = 0.005), or celecoxib (P < 0.001). At the same time, a dramatic delay of tumor progression was observed in the combined treatment compared with all other three groups. Molecular analysis showed that the combined treatment significantly decreased prostaglandin E metabolite production. The cooperative effect of these two agents in combination was also associated with down-regulation of phosphorylated EGFR, phosphorylated extracellular signal-regulated kinase, and phosphorylated signal transducers and activators of transcription 3 levels and reduction of vascular endothelial growth factor and Ki-67 expression. Specifically, gene silencing of both EGFR and COX-2 by small interfering RNA further confirmed the cooperative antitumor effect.

CONCLUSION:

The current results strongly suggest that a cooperative effect of the combined treatment on tumor progression is mediated through blocking both EGFR- and COX-2-related pathways. This combination regimen may provide a promising strategy for cancer therapy and chemoprevention in SCCHN.

Comment in

PMID:
16144930
[PubMed - indexed for MEDLINE]
Free full text

Publication Types, MeSH Terms, Substances, Grant Support

Publication Types

MeSH Terms

Substances

Grant Support

PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire
    Loading ...
    Write to the Help Desk