Immunophenotypic analysis of normal mucosa and squamous cell carcinoma of the oral cavity

Detection of tumor-associated alterations in peritumoral normal mucosa may give insight into the molecular pathogenesis of oral cancer. In the present study, 100 archival oral squamous cell carcinomaswith adjacent nontumorous mucosa were immunohistochemically investigated with antibodies against p53 , Mdm2, Bcl-2, WAF1, MIB1, epidermal growth factor receptor (EGF-R), and va rious CD44 isoforms. Additionally a standardized argyrophilic nucleolar org anizer region (AgNOR)-associated proteins analysis was performed. No correl ation was found between p53, Mdm2, Bcl-2, and WAF1 immunophenotypes of the respective tumors and adjacent mucosa. The proliferation-associated markers MIB1 and AgNORs showed a statistically significant sequential increase fro m normal to dysplastic mucosa to invasive carcinoma. investigation of vario us CD44 adhesion molecules revealed a highly variable expression pattern in overt carcinomas with a significantly decreased expression of CD44 v4 and v9 variants and unaltered strong expression of v5 and v6 isoforms compared with normal oral epithelium. We conclude that proliferation markers (MIBI a nd AgNORs), as well as selected CD44 isoforms, represent useful markers for the assessment of precancerous lesions. They may be utilized for screening patients at high risk for the development of oral cancer.