Detection of proteins and mRNA of p16, p53 and nm23 in mucoepidermoid carcinoma of salivary glands and their prognostic significance

Objective To disclose the relationship between the expression of p16, p53 and nm23 and the significant morphologic characteristics in mucoepidermoid carcinoma. Methods The proteins and mRNA in paraffin blocks from 41 mucoepidermoid carcinoma patients were studied with immunohistochemical methods and in situ hybridization respectively. Results The negative expression of p16 was found in 62.5% (15/24) of the low differentiation grade and in 29.4% (5/17) of the high differentiation grade ( P =0.037). The positive p53 expression was detected in 70.8% (17/24) of the low grade neoplasms and in 23.5% (4/17) of the high grade ( P =0.003), while positive nm23 protein was present in 37.5% (9/24) and 64.7% (11/17) respectively ( P =0 086). However, no relationship was found between positive mRNA of p16, p53, nm23 and WHO pathologic grade. Conclusions There is a significant correlation between expression of p16 and p53 and WHO pathologic grade of mucoepidermoid carcinoma, which indicates clinical prognostic significance. No correlation is noticed between the pathologic grade and the expression of nm23 protein and mRNAs of p16, p53 and nm23.