Chemopreventive effect of montelukast in n-nitroso n-methyl urea induced mammary carcinogenesis in female Sprague-Dawley rats

OBJECTIVE: The objective of the study was to evaluate the chemopreventive effect of montelukast sodium; selective reversible cysteinyl leukotriene D(4)-receptor antagonist in N-nitroso N-methyl urea (NMU) induced mammary carcinogenesis in virgin female Sprague-Dawley rats. MATERIALS AND METHODS: Thirty rats were divided into five groups (normal control, disease control, montelukast1 mg/kg, montelukast10 mg/kg, tamoxifen10 mg/kg) of six animals each. The drug was administered in two doses,1 mg/kg,and 10 mg/kg orally and compared with the standard drug tamoxifen (10 mg/kg)p.o. RESULTS: Montelukast sodium 1 mg/kg,10 mg/kg, and tamoxifen10 mg/kg decreased the tumor incidences by 50%,66.67%, and 83.33% and the total number of tumors in group by 41.67%, 58.33% and 91.67% respectively, when compared to the disease control. Montelukast sodium 1 mg/kg,10 mg/kg,and tamoxifen10 mg/kg decreased the average tumor burden by 86.41%,94.8% and 95.97%and average tumor volume by 89.52%, 95.84%, and 95.4%respectively, when compared to disease control group. CONCLUSION: The results revealed that montelukast sodium prevent the mammary carcinogenesis and confirms the role of cysteinyl leukotriene D(4)-receptor in mammary gland neoplasia.