p53 Expression in Malignant Melanoma and Melanocytic Nevus

Yang, Jun Sung; Chae, Young Soo; Suh, Kee suck; Kim, Sang Tae

Abstract

BACKGROUND: The p53 gene mutations are the most frequent genetic alterations found in human skin cancer. However, many studies on the expression of p53 protein in human melanoma and melanocytic nevus have been controversial.
OBJECTIVE
This study was conducted to investigate the differences in p53 protein expression associated with tumor thickness variance, subtypes and, benign and malignant melanocytic tumors.
METHODS
Immunohistochemical analysis of p53 protein was performed on the formalin-fixed, paraffin-embedded tissue sections of 22 melanocytic nevi and 29 malignant melanomas(20 primary and 9 metastatic) using anti-p53 monoclonal antibody with an avidin-biotin peroxidase complex procedure.
RESULTS
1. Mutant p53 protein was detected in 55.2%(16/29) of malignant melanomas, whereas mutant p53 protein was not detected in melanocytic nevi.(p<0.05) 2. Metastatic malignant melanoma(8/9, 88.9%) showed a significantly higher p53 protein detection rate compared to primary malignant melanoma.(8/20, 40.0%) (p<0.05).
CONCLUSION
The detection rate of p53 protein was higher in malignant melanoma compared to melanocytic nevus. This finding suggests that p53 may play a significant role in the progression and metastasis of malignant melanoma.