P53 PROTEIN EXPRESSION IN HUMAN BREAST-CANCER - AN IMMUNOHISTOCHEMICAL STUDY INCLUDING CORRELATION WITH STEROID-RECEPTOR STATUS, PROLIFERATION INDEXES, COLLAGEN TYPE-IV, LAMININ, C-ERBB-2 ONCOPROTEIN AND CATHEPSIN-D

In a study of 83 breast cancer patients, tumour p53 protein expression was studied by immunohistochemistry using the monoclonal antibody DO- 7. Its relationship with several prognostic variables such as: steroid receptors, c-erbB-2 oncogene, Cathepsin D (CD), proliferative indices Ki-67 and PCNA, as well as with expression of the basement membrane p roteins collagen type IV and laminin was investigated. p53 protein exp ression was detected in 51.8% of tumours (43 of 83). Expression was in dependent of c-erbB-2 overexpression, proliferating index as measured by Ki-67, CD expression and steroid receptor status. Also, p53 accumul ation was not correlated with any other conventional clinicopathologic al parameter considered in this study. A significant positive correlat ion was found between p53 protein expression and collagen type IV expr ession (P < 0.05), and PCNA-LI (P < 0.05). These data suggest that p53 protein could play an important role in the expansion of breast cance r and in proliferative activity, as determined by PCNA-LI. The results do not resolve whether detectable p53 protein expression represents a random product in tumours with high collagen type IV expression or wh ether it is an important feature of the malignant phenotype in the exp ansion of breast cancer.