title: P53 expression in breast cancer.
abstract: Immunohistochemical evaluation of 200 primary breast cancers with the anti-p53 mouse monoclonal antibody (MAb) PAb421 showed positivity in nuclei of malignant cells in 31 cases (15.5%). PAb421+ cases were significantly more frequently epidermal growth factor receptor (EGF-R)-positive (67.7%; p less than 0.001) and estrogen receptor (ER)-negative (73.3%; p less than 0.001); they displayed surface histocompatibility class-1 (80.6%; p less than 0.01) and 11 (74.2%; p less than 0.05) antigens. Low values for progesterone receptor (mean 67.20 +/- 25.2 fmol/mg; p less than 0.05) and a high number of cells positive for the proliferation-associated antigen Ki-67 (log mean 6.88 +/- 0.33; p less than 0.01) were found in PAb421+ tumors as well as a high number of grade-3 infiltrating duct carcinomas (70%; p = 0.01). Of the 200 cases of mammary carcinoma, 88 were further analyzed using another human specific anti-p53 MAb PAb1801, and 40 (45.5%) were found positive. This MAb stained all the PAb421+ cases and was significantly associated with negative ER status (39.5%; p less than 0.05) and high Ki-67 scores (log mean 6.93 +/- 0.24; p = 0.001). Analysis of PAb1801+/Pab421- cases for HLA antigens, EGF-R and ER showed a phenotype similar to that of the p53-ve/ER+ carcinomas, except for the high Ki-67 score. No differences in age of the patient, number of involved nodes, tumor size, ploidy or labelling index scores were evident between p53+ and carcinomas. We concluded that p53 in mammary carcinomas is associated with ER-negative, growth factor receptor-positive, high-grade tumors, and is a promising new parameter to evaluate the cellular biology and prognosis of breast cancer.
authors.affiliation: Division of Anatomic Pathology and Cytology, Istituto Nazionale per lo Studio e la Cura dei Tumori, Milan, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Cattoretti
authors.forename: F
authors.initials: F
authors.lastname: Rilke
authors.forename: S
authors.initials: S
authors.lastname: Andreola
authors.forename: L
authors.initials: L
authors.lastname: D'Amato
authors.forename: D
authors.initials: D
authors.lastname: Delia
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000032:analysis*; D001940:Breast / Q000032:analysis; D001943:Breast Neoplasms / Q000032:analysis*; D004273:DNA, Neoplasm / Q000032:analysis; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000032:analysis*; D009687:Nuclear Proteins / Q000032:analysis*; D010750:Phosphoproteins / Q000032:analysis*; D011003:Ploidies; D011960:Receptors, Estrogen / Q000032:analysis; D016159:Tumor Suppressor Protein p53
chemical_list: D014408:Biomarkers, Tumor; D004273:DNA, Neoplasm; D009363:Neoplasm Proteins; D009687:Nuclear Proteins; D010750:Phosphoproteins; D011960:Receptors, Estrogen; D016159:Tumor Suppressor Protein p53