Relationship between expression of P16 protein and cell proliferation in breast cancer tissue

[Objectives] To investigate the expression of P16 protein and its correlation with cell porliferation.[Methods] Expression of P16 protein and PCNA were tested in 53 breast cancer tissues with SABC immunohistochemical methods.[Results] Positive rates of P16 protein and PCNA in 53 breast cancer were 54.7%(29/53) and 71.7%(38/53).Their expressions were not correlated with patient's age,tumor size,menopause,ER and PR(P 0.05);but correlated with the histological grade,clinical TNM stage,lymphoid node metastasis,and 5-years survival(P 0.05).There were significant correlation between the expressions of P16 and PCNA in breast cancer.[Conclusion] The expression of P16 protein and PCNA is closely related to tumor invasion,lymph-node metastasis of breast carcinoma(BC),and they could be used as a biologic marker for breast cancer.P16 protein may serve as an important indicator of estimating prognosis of breast cancer.