Mass Spectrometry Proteomic Analysis of Four p53 Patterns in Differentiated Vulvar Intraepithelial Neoplasia
Objective
The histopathologic diagnostic criteria of differentiated vulvar intraepithelial neoplasia (dVIN), the precursor of human papillomavirus-independent squamous cell carcinoma, are basal atypia, a negative or non–block-positive p16, and a supportive p53 immunohistochemistry (IHC). Several different patterns of supportive p53 IHC have been described. This study aims to determine the relationship between p53 IHC patterns and mass spectrometry analysis of cellular proteins in dVIN.
Methods
Four patterns of p53 IHC were studied: overexpression, cytoplasmic, wild type, and intermediate expression between wild type and overexpression. For each pattern, tissue samples of 4 examples were subjected to mass spectrometry.
Results
The protein profile within each p53 IHC pattern shared common features. Each of the 4 p53 patterns had a distinguishable protein profile when compared with the other 3 patterns.
Conclusions
The distinguishable protein profiles in different p53 IHC patterns suggest diverse mechanisms of TP53 dysfunction. Subtyping dVIN by p53 IHC is worthy of further study because varied protein expression profiles may translate into different clinical behavior.