Alterations of p53 and Bcl-2 protein expression in the recurrent laryngeal and pharyngeal squamous cell carcinoma

Abstract

Background Identification of molecular events of the recurrent squamous cell carcinoma (SCC) of the larynx and pharynx may aid in refining treatment strategies and improving outcome. The underlying molecular events of these recurrent tumors involve alterations in the tumor suppressor genes (p53) and protooncogenes (Bcl-2). We hypothesize that the development of these recurrent tumors involves alterations of the p53 and Bcl-2 proteins. Methods To test this hypothesis, 15 laryngeal and pharyngeal biopsy specimens obtained from 15 patients with recurrent laryngeal or pharyngeal SCC with different grades (II-IV) were immunostained for p53 and Bcl-2 protein expression. Results Examination of the percentage of positive cells in the normal mucosa and SCC, respectively, showed significant up-regulation of p53 (0.0 ± 0.0 vs 51.8 ± 5.9, P = .00) and Bcl-2 protein expression (36.5 ± 3.5 vs 74.6 ± 1.9, P = .00). Conclusions Alterations of the p53 and Bcl-2 proteins occur during the development of recurrent SCC. Additional studies are needed to confirm and extend our results.