p53 protein expression patterns associated with TP53 mutations in breast carcinoma

Area of Science:

• Oncology
• Molecular Biology
• Genetics

Background:

• TP53 gene mutations are significant in various cancers, including breast cancer (BC).
• The reliability of p53 protein expression as a biomarker for TP53 mutations in BC requires further investigation.

Purpose of the Study:

• To assess the accuracy of p53 protein expression via immunohistochemistry (IHC) as a predictor of TP53 gene mutations in breast cancer patients.
• To explore the correlation between specific p53 protein expression patterns and distinct TP53 genetic alterations.

Main Methods:

• TP53 gene mutations were identified using next-generation sequencing (NGS).
• p53 protein expression levels were evaluated using immunohistochemistry (IHC) in 64 breast cancer samples.

Main Results:

• Abnormal p53 expression patterns were observed in 55% of breast cancers, with TP53 mutations found in 53% of tumors.
• Abnormal p53 protein expression accurately predicted TP53 mutations in 97% of cases, while wild-type patterns predicted the absence of mutations in 93% of cases (p < 0.0001).
• p53 IHC overexpression correlated with missense mutations, whereas null patterns were associated with truncating mutations and triple-negative breast cancer phenotypes.

Conclusions:

• Immunohistochemistry (IHC) for p53 protein shows potential as a surrogate marker for TP53 mutations in breast cancer.
• Specific p53 protein expression patterns may indicate particular TP53 genetic mutations, offering valuable diagnostic insights.