Significance of microsatellite instability and expressions of cyclin D1 and P53 proteins in breast carcinoma induced by DMBA in rats / 第三军医大学学报

ABSTRACT

Objective To investigate the significance of microsatellite instability(MSI) and expressions of cyclin D1 and P53 in 7,12 dimethylbenz(a)anthracene (DMBA) induced breast carcinoma in rats. Methods Animal model of rat breast carcinoma was duplicated in 30 female Wistar rats by gastric irrigation of DMBA at the dose of 200 mg/kg. Eight microsatellite loci(D1Mitl4, D1Mgh2, D1Mgh6, D3Mit3, D3Mgh9, D5Mitll, D5Mgh5 and D7Mgh1) were selected for the examination of MSI of breast carcinoma by PCR analysis. S P immunohistochemical staining was used to study the expressions of cyclin D1 and P53 in DMBA induced breast carcinoma in rats. Results Of the 27 cases of breast carcinoma, there were 2 cases of MSI at 8 loci, 9 cases with P53 overexpression and 12 cases with cyclin D1 overexpression. All these were associated with histological grading. Conclusion MSI is infrequent in breast carcinogenesis in rats. Cyclin D1 overexpression may be the early event but P53 protein overexpression may be the late event in breast carcinoma.