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.
Our results in this group of patients and the heterogeneity of the staining of tumour cells in tissue sections suggest that p53 mutations could be a late event in this non-familial form of breast cancer.
A number of independent groups using different methods of detection have shown that p53 alterations are associated with more aggressive tumor biologic factors and a poorer prognosis in breast cancer patients.
The presence of p53 autoantibodies provides important additional information to immunochemistry and may identify patients with aggressive histological types of breast cancer.
In addition, the availability of normal and tumor-derived epithelial cells with known p53 sequences from a single breast cancer patient should facilitate understanding of the p53 regulation in mammary cells.
Our data confirm previous reports of a putative tumour-suppressor gene, distinct from TP53, on distal chromosome 17p which is associated with breast cancer.
In light of the wealth of information in the Li-Fraumeni literature that associates germline TP53 mutations with a variety of malignancies, this testing may have important consequences for risk assessment for other close relatives, including early-onset breast cancer in the mothers.
Regardless of differences in their protein-expression pattern, a majority of the p53 gene mutations were suggested to function in a recessive mode and to be involved in the development of histologically aggressive breast cancer.
In the other case, a deletion resulting in a frameshift in the C-terminal coding region of p53 was found in a woman who was diagnosed with breast cancer at age 34.
In the present study, we determined frequencies and types of the p53 mutations in breast cancer tissues in women with a history of benign breast disease (BBD) identified in Florence, Italy, with (n = 6) or without (n = 10) a family history of breast cancer.
Thus, p53 gene alteration in breast cancer may occur in highly malignant breast cancer other than advanced clinical stage cancer or node-positive cancer.
The number of known genes for which there is now good evidence for their role in the development of breast cancer is still limited, and basically restricted to TP53 and ERBB2.
The expression of Bcl-2 and p53 was detected by immunohistochemistry on paraffin-embedded sections from 283 node-negative resectable breast cancers treated with local-regional therapy alone until relapse.