Therapeutic effect of CS-706, a specific cyclooxygenase-2 inhibitor, on gallbladder carcinoma in BK5.ErbB-2 mice.

Abstract

Biliary tract cancer is still challenging to treat and manage due to its poor sensitivity to conventional therapies and the inability to prevent or detect the early tumor formation. The most well known risk factor for gallbladder cancer is the presence of chronic inflammation, usually related to gallstones. It has been suggested that cyclooxygenase-2 (COX-2) plays a variety of roles in the gastrointestinal tract, including pathogenic processes such as neoplasia. Recently, we have generated transgenic mice that overexpress rat ErbB-2 under the control of bovine keratin 5 promoter (BK5.ErbB-2 mice). Homozygous BK5.ErbB-2 mice develop adenocarcinoma of gallbladder with an approximately 90% incidence. In addition to the activation of ErbB-2 and epidermal growth factor receptor, mRNA and protein levels of COX-2 were up-regulated in the gallbladder carcinomas that developed in these transgenic mice. The aim of this study was to examine the effects of a COX-2 inhibitor, CS-706, on the development of gallbladder carcinomas using the BK5.ErbB-2 mouse model. Ultrasound image analysis as well as histologic evaluation revealed a significant therapeutic effect of CS-706 on the gallbladder tumors, either as reversion to a milder phenotype or inhibition of tumor progression. The antitumor effect was associated with inhibition of prostaglandin E(2) synthesis. CS-706 treatment also down-regulated the activation of ErbB-2 and epidermal growth factor receptor, resulting in decreased levels of phosphorylated Akt and COX-2 in gallbladder cancers of BK5.ErbB-2 mice. Based on our results, targeting COX-2 could provide a potentially new and effective therapy alone or in combination with other therapeutic agents for patients with biliary tract cancer.

• Authors: Kaoru Kiguchi, Lynnsie Ruffino, Toru Kawamoto, Eugenia Franco, Shin-ichi Kurakata, Kosaku Fujiwara, Masaharu Hanai, Mohammad Rumi, John DiGiovanni
• Journal: Molecular cancer therapeutics (Mol Cancer Ther) Vol. 6 Issue 6 Pg. 1709-17 (Jun 2007) ISSN: 1535-7163 [Print] United States
• PMID: 17575102 (Publication Type: Journal Article, Research Support, N.I.H., Extramural)

Chemical References

• Cyclooxygenase Inhibitors
• Pyrroles
• Sulfonamides
• apricoxib
• Cyclooxygenase 2
• ErbB Receptors
• Receptor, ErbB-2
• Dinoprostone

Topics

• Administration, Oral
• Animals
• Cyclooxygenase 2 (drug effects)
• Cyclooxygenase Inhibitors (administration & dosage, therapeutic use)
• Dinoprostone (antagonists & inhibitors, biosynthesis)
• ErbB Receptors (metabolism)
• Fluorescent Antibody Technique
• Gallbladder Neoplasms (drug therapy, metabolism)
• Mice
• Mice, Transgenic
• Pyrroles (administration & dosage, therapeutic use)
• Receptor, ErbB-2 (metabolism)
• Sulfonamides (administration & dosage, therapeutic use)