Expression of cyclin-dependent kinase inhibitor p27~(kip1) and estrogen receptor in human breast carcinoma

Objective:To assess the distribution and the expression of p27 KIP1 and estrogen receptor(ER)in breast diseases and to investigate the differences in expression level between the benign and malign diseases. Methods:Immunohistochemical staining (DAKO EnVision TM Systems) was used to detect the expression of p27 KIP1 and ER in 32 cases of adenosis, 35 cases of fibroadenoma and 24 cases of breast carcinoma. Results:Immunohistochemical staining showed positivity of p27 KIP1 with varying intensities in 29.2%(7/24) of breast carcinoma, 65.6% (21/32) of adenosis and 60.0% (21/35) of fibroadenoma, respectively. The expression of p27 KIP1 was significantly different among three groups. Positivity of ER was in 66.7%(16/24) of breast carcinoma, which was significantly higher than that of adenosis (34.4%) and fibroadenoma (37.1%). Conclusion:The expression of p27 KIP1 and ER may play a significant role in the tumorigenesis and may reflect the prognosis of breast carcinoma.