RESUMO
Generally, benign breast lesions behave as innocuous and limited proliferations, but sometimes they can represent pre-cancerous diseases. The practical importance of epithelial hyperplasias studies is related to their potential for malignant transformation. The TP53 tumor supressor gene suffers the greatest number of mutations in human cancer Using single strand conformational polymorphism, we did a mutation screening in exons 5 to 8 of the TP53 gene in the tumoral tissues of five patients with epithelial hyperplasias of the breast. The obtained results do not show any polymorphism that indicates mutation. The lack of mutation indicates that this gene is not involved in the initial process of malignization, strengthening the hypothesis that mutations on TP53 gene are a late event in the breast carcinogenesis.
Assuntos
Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Mama , Neoplasias da Mama , Doenças Mamárias/genética , Doenças Mamárias/patologia , Genes p53 , Hiperplasia , Polimorfismo Conformacional de Fita SimplesRESUMO
Accessory breasts are a clearly hereditary anomaly. They enlarge during pregnancy and lactation as a consequence of high blood levels of estrogen and prolactin, and are subject to all the diseases that occur in normal breasts. Cytogenetic analysis was performed on one accessory breast. The monossomy of chromosome 16 was the main alteration found in this materal. Nonscheduled cell proliferations may produce chromosome alterations, most of them with no clinical meaning. When relevant genes are altered, major proliferations or progression to malignancy may occur.