P44 Expression In Benign And Malignant Breast Lesions

Objective:To detect the expression levels of p44 in normal breast tissue, usual ductal hyperplasia, atypical ductal hyperplasia, carcinoma in situ and invasive carcinoma. This study explores the expression patterns of p44 and its relationship with the development of breast cancer.Methods:In our research, a total of 118 cases of human breast tissue samples of paraffin block are from Department of Pathology, the Chengdu Military Region, Kunming General Hospital from May 2012 to May 2015, including breast carcinoma (n=37), ductal carcinoma in situ (n=16), atypical ductal hyperplasia (n=17), usual ductal hyperplasia (n=21), normal breast tissue(n=27). Immunohistochemistry method was used to detect the p44 expression in each group. Then we analyzed quantitative the differentially expressed between the groups by using histological score (HSCORE), and the relationship between p44 expression and correlation with clinicopathological features of breast cancer.Results:(1) The expression of p44 in the nucleus and cytoplasm of samples of benign and malignant breast lesions are positive.In normal breast tissue and usual ductal hyperplasia group p44 expressed mainly in the cytoplasm, but the p44 expressed mainly in the nucleus in the breast atypical ductal hyperplasia, ductal carcinoma in situ and invasive carcinoma group. (2) In invasive breast cancer group,86.49%(32/37) of samples of p44 nuclear cytoplasm HSCORE ratio greater than 1; in DCIS group, 81.25%(13/16) of samples of p44 nuclear cytoplasm HSCORE greater than 1 and in atypical ductal hyperplasia group,100%(17/17) of samples of p44 nuclear cytoplasm HSCORE ratio is greater than 1; 100%(21/21) usual ductal hyperplasia and 100% (27/27) in normal breast tissue samples cytoplasm HSCORE nuclear p44 is less than 1. To compare the expression of p44 in the nucleus and cytoplasm, significant difference existed in five groups of samples(P<0.05). Further compared the expression of p44 in the nucleus of usual ductal hyperplasia cases with normal breast tissue group, there are statistical differences, P<0.05. p44 expressed in atypical ductal hyperplasia, ductal carcinoma in situ and breast carcinoma, there was no statistically significant difference, P> 0.05.(3) The expression of p44 in breast canccer was not correlated with patient’s age, tumor size, PR, HER-2 expression status and lymph node metastasis (P> 0.05), but was significantly correlated with tissue differentiation degree (P< 0.05).Meanwhile in patients with the estrogen receptor (ER) positive, the expression of p44 has obvious relationship with the proliferative index (Ki-67) (P<0.05).Conclusion:(1) p44 protein in benign breast lesions mainly expressed in the cytoplasm, whereas in malignant lesions mainly expressed in the nucleus, the result suggests that the nucleus of p44 may play an important role in the development of breast cancer. (2) The phenomenon is that cytoplasm to the nucleus translocation from benign and malignant breast lesions, the result indicate that p44 may have distinct biological functions in different cellular compartments. (3) In the study of breast solid tumors, the cells with estrogen receptor-positive breast cancer, the expression of nuclear p44 was positively correlated with breast cancer cell proliferate, indicating that p44 may be an important role in promoting the proliferation of tumor-associated genes.