title: BRCA1-p53 relationship in hereditary breast cancer.
abstract: BRCA1, a major gene predisposing to breast and ovarian cancers, encodes a ring finger-containing protein. Its function is still unknown. Recently, the existence of a new structural domain called BRCT was postulated. This domain has some similarity with the 53BP1 human protein involved in p53 binding process. To test for a possible relationship between BRCA1 and p53, we compared p53 expression by immunohistochemical analysis in 29 BRCA1-associated breast cancers from 19 families, and in 200 consecutive sporadic breast cancers. We observed a prevalence of tumors with p53 positive staining in the BRCA1 population (p=0.003). In addition, p53 expression was affected by the site of the germ line mutation in the BRCA1 gene. p53 staining was found more consistently in tumors associated with mutations that lead to a truncation of BRCA1 in the ring finger region (p=0.0048). These results favor the hypothesis of a cooperation between BRCA1 and p53. Further experiments are needed to explore the full bilogical relevance of this phenomenon.
authors.affiliation: INST J PAOLI I CALMETTES,LAB TUMOR BIOL,F-13009 MARSEILLE,FRANCE. INST CURIE,UNIT GENET ONCOL,PARIS,FRANCE. INST GUSTAVE ROUSSY,DEPT BIOL CLIN,F-94805 VILLEJUIF,FRANCE. CTR OSCAR LAMBRET,LAB HUMAN MOL ONCOL,F-59020 LILLE,FRANCE. INST GUSTAVE ROUSSY,DEPT PATHOL,VILLEJUIF,FRANCE. INSERM U119,MARSEILLE,FRANCE. INST J PAOLI I CALMETTES,DEPT PATHOL,F-13009 MARSEILLE,FRANCE.
authors.forename: H
authors.initials: H
authors.lastname: Sobol
authors.forename: D
authors.initials: D
authors.lastname: Stoppalyonnet
authors.forename: B
authors.initials: B
authors.lastname: Bressacdepaillerets
authors.forename: J
authors.initials: J
authors.lastname: Peyrat
authors.forename: J
authors.initials: J
authors.lastname: Guinebretiere
authors.forename: J
authors.initials: J
authors.lastname: Jacquemier
authors.forename: F
authors.initials: F
authors.lastname: Eisinger
authors.forename: D
authors.initials: D
authors.lastname: Birnbaum