The proliferative activity of cancer cells in oral squamous cell carcinoma has been identified as an important predicator of biologic behavior and as a potential guide for cancer therapy. The proliferative capacity was analyzed immunohistochemically using monoclonal antibody against PCNA and p53 protein in biopsy or surgical resected specimens from 51 cases with oral squamous cell carcinoma (SCC). The results were as follows : 1) There was a significant difference in PCNA score between p53 protein-positive cases and p53 protein-negative cases ; 37.9±11.9% (n=28), 30.8±11.1% (n=23)(p<0.05). 2) The immunostaining of p53 protein and PCNA was localized in similar areas of oral cancer tissue. These results suggest that the PCNA and p53 protein detection by immunohistochemically method was valuable for assessment of proliferative activity and more aggressiveness with oral squamous cell carcinoma.
