Expression of Cyclin D1 in Different Molecular Subtypes of Breast Cancer and Its Impact on Prognosis

Objective To detect the expression of cyclin D1 in different kinds of clinical molecular subtypes of breast cancer tissue, and to analyze the relationships of the expression to clinicopathologic characteristics and prognosis. Methods The expression of cyclin D1 was detected in 175 cases of different kinds of clinical molecular subtypes of breast cancer by immunohistochemical method. The expression was compared among different kinds of clinical molecular subtypes of breast cancer by chi-square test. The correlations with clinicopathologic characteristics were analyzed by Spearman rank correlation. The impact of different expression of cyclin D1 on the prognosis was analyzed by the KaplanMeier survival curve. Results ① In the positive expression group of cyclin D1 in the breast cancer, Luminal A type was the highest proportion(P0.05);but in the negative expression group of cyclin D1 in the breast cancer, Luminal B type was the highest proportion(P0.05). ② The expression of cyclin D1 had no correlation with clinical stage, histological grade or PR(P0.05), was positively correlated with number of lymph node metastasis(rs =0.197,P0.01) or ER(rs =0.139,P0.05), was negatively correlated with Her-2(rs =-0.131, P0.05). ③ The positive expression of cyclin D1 was stronger, the tumor free survival time was longer(P 0.05). Conclusion This study shows that there is a correlation between the positive expression of cyclin D1 and ER, Her-2, or number of lymph node metastasis, and its positive expression prompts a relatively good prognosis, can be used as the prognosis indicator for breast cancer.