p53 protein overexpression and gene mutation in mixed Müllerian tumors of the uterus

Alteration of the p53 tumor suppressor gene is associated with poor prognosis in many human cancer types. We examined the incidence and prognostic significance of p53 gene alterations in a series of uterine malignant mixed Müllerian tumors (MMT). Nuclear overexpression of p53 protein detected by immunohistochemistry (IHC) with the DO-7 antibody was observed in 12 of 24 (50%) tumors. Mutation of the p53 gene detected by single-strand conformation polymorphism (SSCP) of exons 5 to 8 was found in 11 of 24 (46%) tumors. The incidence of p53 alteration in uterine MMT was significantly higher than in several common epithelial tumor cell types previously investigated in our laboratory using identical techniques. However, unlike these tumors alteration of the p53 gene does not appear to be of prognostic importance in uterine MMT.