Study of biological characteristics and incidence of spontaneous mammary tumor in razi mice, a worthwhile model for mammarytumor, iranian origin

ABSTRACT

Razi mouse is originally established from native Iranian mice at Razi institute and is susceptible to spontaneous mammary tumor. In this study, incidence, age and predisposing factors of tumor and some of biological characteristics of this strain were studied. There were significant differences in incidence of mammary tumor in Razi virgin females as compared with normally breeding and hormone treated breeding females in p < 0.05 but was the same with virgin NMRI females foster-nursed on Razi dams. However incidence in virgin Razi females foster-nursed on NMRI dams was very lesser than three mentioned groups. All mammary tumor tissues were histopathologically diagnosed adenocarcinoma. No significant differences were found in the levels of biological factors studied in tumor bearing and nonbearing Razi mice [p < 0.05]. Our results showed that milk factor may play the most important role in compare with genetic background and hormonal stimulation for development of mammary tumor in Razi mouse. Razi strain may represent a unique model to study of mammary tumor etiology and anticancer therapy