Apoptosis in osteosarcoma: relationship with p53 and bcl 2 expression

Objective: To investigate whether apoptosis is related to the expression of p53 and bcl 2,the degree of proliferation, and their prognostic significance in osteosarcomas. Methods: Apoptotic cells was detected by using DNA nick end labeling method and the expression of p53, bcl 2 and proliferating cell nuclear antigen (PCNA) by immunohistochemical staining in 80 osteosarcoma cases. Results: The apoptosis index (AI) ranged from 0.63%to 18.8%in 80 cases. The detecting rates of p53 and bcl 2 oncoprotein were 37.5%and 60%,respectively. The PCNA index ranged from 12%to 96%. Regression analysis demonstrated a positive correlation between apoptosis and p53 expression or PCNA index ( P 0.05), and a negative correlation between apoptosis and bcl 2 expression ( P 0.05), whereas no relationship was found between p53 and bcl 2 expression. Conclusions: These data suggest that p53 and bcl 2 may play an important role in regulating apoptosis. All of apoptosis, p53, bcl 2 and PCNA may be important factors affecting the prognosis of patients with osteosarcoma.