Correlation of Apoptosis with HPV, p53 Expression, and PCNA Expression in Laryngeal Squamous Cell Carcinoma

Hwang, Chan Seung; Kim, Gi Bum; Han, Byung Sang; Yang, Hoon Sik; Kim, Chun Gil

Abstract

BACKGROUND AND OBJECTIVES: Programmed cell death (apoptosis) is distinctive form of cell death manifested by characteristic chromatin condensation and DNA fragmentation, whose function is the deletion of cells in normal development, organogenesis, immune function, and tissue growth, but which can also be induced by pathologic stimuli. The purpose of this study was to analyze the relationship between apoptotic index and HPV, p53 and PCNA expression, and clinicopathological findings in laryngeal squamous cell carcinomas.
MATERIALS AND METHODS
Fourty-one cases of laryngeal squamous cell carcinomas were analyzed for the detection of HPV DNA by in situ hybridization, the expression of p53 and PCNA by immunohistochemical technique, and detection of apoptotic bodies by in situ hybridization.
RESULTS
HPV DNA was detected in 8 (19.51%), p53 was expressed in 26 (63.41%) out of 41 cases, and the PCNA expression rate was 48.39+/-21.06%. The average apoptotic index was 9.38+/-2.89, there was no relationship between apoptotic index and HPV and p53 expression (p>0.05). The apoptotic indices were 11.26+/-1.86, 8.17+/-2.55, and 4.32+/-2.41 in well differentiatied, moderately differentiatied and poorly differentiatied carcinoma, respectively. The histopathological differences were statistically significant (p<0.05). Also there was an inverse proportion between apoptotic index and PCNA expression.
CONCLUSION
The apoptotic index was related to cellular differentiation regardless of HPV and p53 expression. Also these results suggest that the numbers of apoptotic bodies in the tumor tissues can make it possible to presume indirectly the malignant potentiality of the tumor and will help us to understand the biologic behavior of head and neck cancer.