{Reference Type}: Journal Article
{Title}: p53 protein expression patterns associated with TP53 mutations in breast carcinoma.
{Author}: Anderson SA;Bartow BB;Harada S;Siegal GP;Wei S;Dal Zotto VL;Huang X;
{Journal}: Breast Cancer Res Treat
{Volume}: 207
{Issue}: 1
{Year}: 2024 Aug 20
{Factor}: 4.624
{DOI}: 10.1007/s10549-024-07357-z
{Abstract}: <B>OBJECTIVE: </B>The importance of a TP53 mutation has been demonstrated in several tumor types, including breast cancer (BC). However, the accuracy of p53 protein expression as a predictor of gene mutation has not been well studied in BC. Therefore, we evaluated p53 protein expression associated with TP53 mutations in breast cancers from 64 patients.<BR><B>METHODS: </B>TP53 mutation was examined using next-generation sequencing (NGS). p53 protein expression was examined using immunohistochemistry (IHC).<BR><B>RESULTS: </B>Among the 64 BCs, 55% demonstrated abnormal expression patterns including 27% overexpression, 22% null, 6% equivocal with 45% having a wild-type pattern. A TP53 mutation was present in 53% (34/64) of tumors including 30% (19/64) demonstrating a missense mutation, 11% (7/64) with a frameshift mutation, 11% (7/64) with a nonsense mutation, and 3% (1/64) with a splice site mutation. Abnormal expression of p53 protein was present in 33 of 34 (97%) tumors carrying a TP53 mutation; conversely, a wild-type pattern was present in 28 of 30 (93%) tumors without a detectable mutation (p < 0.0001). The majority of BCs with a p53 IHC overexpression pattern (15/17, 88%) contained a missense TP53 mutation; while the majority of BCs with a null pattern (12/14, 86%) contained a truncating mutation (p < 0.0001). The BCs with a null pattern are associated with a high Nottingham histological grade and a triple-negative phenotype when compared to those demonstrating overexpression (p < 0.05).<BR><B>CONCLUSIONS: </B>These findings suggest that p53 IHC can be a potential surrogate for TP53 mutations in BC. Different p53 expression patterns may correlate with specific TP53 genetic mutations in BC.