There was complete concordance between p53 gene mutation and p53 protein accumulation in the 15 snap-frozen carcinomas and in both breast carcinoma cell lines.
We have investigated the expression of ras p21, Rb1 and p53 proteins in human breast cancer patients immunohistochemically, and correlated the results with a range of clinical and pathological parameters.
Our findings indicate that in invasive breast carcinomas structural abnormalities of the p53 gene are mainly seen in medullary and ductal tumors and that the other histological types, especially those associated with a high level of differentiation and favorable prognosis, show a very low incidence of p53 mutations.
Here we provide biological evidence for the presence of a growth suppressor gene(s) on chromosome 17 that results in the in vitro growth suppression of the p53 wild-type MCF 7 breast cancer cell line.
No sequence alterations of the p53 gene were detected in either the melanoma or nasopharyngeal tumours and only 19% of the primary breast carcinomas showed a variant band indicative of a mutation.
In order to clarify the clinical significance of mutations of the p53 gene and amplification of the c-erbB-2 gene in breast carcinoma, these gene alterations were examined in 101 invasive, seven predominantly intraductal and 10 intraductal breast carcinomas by single-strand conformation polymorphism-direct sequencing or Southern blot-hybridization analysis. p53 mutations were detected in 32 (32%) of the invasive cases and two (12%) of the 17 intraductal/predominantly intraductal cases, whereas c-erbB-2 amplification was detected in 14 (14%) of the invasive and six (35%) of the intraductal/predominantly intraductal cases.