Clinical Significance and Expression of cyclin D2, CDK4 in Human Breast Carcinoma

Objective 　To investigate the expression level of cyclinD2 and CDK4 protein in breast carcinoma, and their relationship to p27^kip1protein and clinicopathological factors as well as the prognostic factors in breast carcinoma. Methods 　The SP immunohistochemical technique was used to detect the expressions of cyclinD2, CDK4 and p27^kip1in 96 cases of breast carcinoma and 18 cases of adjacent nontumor normal breast tissue. The relationship between cyclinD2, CDK4 to p27^kip1protein expression and clinicopathological factors were analyzed. Results 　①The positive expressions of cyclinD2, CDK4 and p27^kip1 protein in 96 cases of breast carcinoma were 41. 7 %, 54. 2 % and 38. 5 % respectively. There was a significant difference between carcinoma and normal breast tissue ( P < 0. 001) . ②The expression level of both cyclinD2, and CDK4 protein in breast carcinoma was significantly associated with histological classification, mitotic index, and local recurrence ( P < 0. 05), and little associated with age, tumor size and histological type ( P > 0. 05) . The expression level of CDK4 in breast carcinoma was related to Lymph node metastases and ER status ( P < 0. 01) . ③The loss of p27^kip1protein expression in breast carcinoma was significantly associated with tumor size, histological classification, mitotic index, Lymph node metastases and local recurrence ( P < 0. 05), There was a negative correlation between p27^kip1 and cyclinD2 as well as CDK4 expression in breast carcinoma ( P < 0. 01) . Conclusion 　The expression of cyclinD2 and CDK4 protein may play a important role in the carcinogenesis and progression of breast carcinoma. The loss p27^kip1expression and over-expressed CDK4 was associated with the invasion, metastases and local recurrence, and may be as the indications of biological behavior and prognosis of breast carcinoma.