Loss of heterozygosity and expression of p53 and maspin in oral cavity and oropharyngeal squamous cell carcinoma

Abstract

Problem: To demonstrate the effect of TSGs p53 and maspin in the carcinogenesis and progression of oral cavity and oropharyngeal squamous cell carcinoma by microsatellite analysis and immunohistochemical staining. Methods: From 40 cases of paraffin block specimens of oral cavity and oropharyngeal squamous cell carcinoma, the loss of heterozygosity (LOH) on chromosomes 17 and 18 was analyzed by using microsatellite marker, TP53, D17S796, D17S5, D17S513, D18S86, and D18S87. And the expression of p53 and maspin was investigated via immunohistochemical staining. Clinicopathologic parameters including sex, age, T stage, lymph node metastasis, histopathologic tumor stage, histologic grade, recurrence rate, and disease-free survival rate were compared with the incidence of LOH on chromosomes 17 and 18 and the expression of p53 and maspin. Results: LOH occurs on chromosome 17 in 14 of 24 cases (58%) and on chromosome 18 in 10/21 (48%). The positive expression of p53 and maspin are 63% (25/40), 60% (24/40) in oral cavity and oropharyngeal carcinoma, and 15% (3/20), 20% (4/20) in normal tonsil tissue ( P < 0.05). Among 24 cases with positive maspin expression, 13 (54%) have increased expression of p53. And there is a significant relationship between LOH on chromosomes 17 and 18 and the expression of p53 and maspin ( P < 0.05). Conclusion: This study demonstrates that LOH on chromosomes 17 and 18 and the expression of p53 and maspin may play an important role in carcinogenesis and progression of tumor. Also, it is suggested that p53 and maspin may be useful variables for the prognostic indicator of oral cavity and oropharyngeal squamous cell carcinoma. Significance: This study provides the location of p53 and maspin genes on chromosomes 17 and 18 for future cloning and sequencing. Support: None reported.