Correlation between p53 expression and other prognostic factors in breast cancer

p53 suppressor tumoral gene codifies the nuclear proteins which suppress the cellular proliferation by preventing the entrance of the cells in the division cycle. The loss or inactivation of this protein, by destruction or gene mutation, or by its link to viral oncoproteins, annuls the growths restrictions and favours the malignant transformation. The immunohistochemical determination of the p53 protein accumulation seems to be an efficient mean of selecting breast neoplasias. p53 immunostaining is positive at the level of malignant cells nuclei and negative for normal cells. For this study there were selected 30 patients with breast cancer, treated in the surgical clinics of the County Hospital from Timişoara, during 1993-1995. Immunohistochemical determination of p53 protein was performed on tissular samples formalin fixed and paraffin embedded, using mouse monoclonal antibody DAKO--p53 DO 7 p53 human antiprotein. From the 30 carcinomas studied, 9 (30%) expressed p53 protein, as found in literature. The presence of this protein was more frequent noticed in the infiltrative lobular carcinoma, comedocarcinoma and in medullary carcinoma. Five patients whose tumours presented p53 protein were postmenopausal; in 7 cases (77.7%) the tumoral differentiation degree was G1 or G2.

Significance of the expression of hormone receptors and of p53 protein in breast carcinomas

A certain proportion of breast cancers contain hormone receptors--specific proteins with high affinity and capacity of selective tie of these hormones. There were selected 30 patients presenting breast cancer, treated at the surgical departments from the County Hospital of Timişoara between 1993 and 1995. The identification of hormone receptors was done on 10% formalin-fixed and paraffin-embedded tissue specimens. As anti-hormone receptors, monoclonal and polyclonal antibodies were used. The immunohistochemical identification of positive to hormone receptors cancer cells was obtained, by nucleus staining. Immunohistochemical assay of the accumulation of p53 protein seems to be an efficient means of selecting breast neoplasms. p53 immunostaining is positive at the level of malignant cells' nuclei and negative for normal cells. From the 30 breast carcinomas, 19 (63.3%) were ER+ and 15 (49.9%) were PR+, resulting an increase of the frequency of ER+ tumors together with the age of the patients; 9 cases (30%) expressed p53 protein, harmonizing with the data in the literature.