Immunohistochemical Study on the Expression of p53 and Bcl-2 Proteins in Non-Small Cell Lung Carcinomas

Lee, Ok Ju; Park, Do Youn; Suh, Kang Suek

Abstract

To address the possible prognostic value of p53 and Bcl-2 proteins in non-small cell lung carcinomas (NSCLCs), the authors studied 43 cases of NSCLCs diagnosed between the years 1990 to 1995 at Pusan National University Hospital. The patients were treated either by pneumonectomy or lobectomy of the lung. The expression of p53 and Bcl-2 proteins was semiquantitatively analyzed in paraffin sections by immunohistochemical method and correlated with clinicopathologic prognostic parameters of NSCLCs. Overexpression of the p53 protein was found in 31 cases (72.1%) of the 43 NSCLCs. Overexpression of the p53 protein was significantly correlated with the decreasing degree of histologic differentiation, increasing tumor stage, and cigarette smoking. Bcl-2 expression was found in 19 cases (44.2%) of the 43 NSCLCs. Increased expression of the Bcl-2 protein was significantly correlated only with decreasing tumor stage. An inverse relationship was found between p53 and Bcl-2 proteins, but it was not statistically significant. Thus p53 and Bcl-2 proteins, as demonstrated immunohistochemically in routine paraffin sections, could be of value in prediction of the aggressiveness and prognosis of NSCLCs, in agreement with the central role of p53 and Bcl-2 proteins in the evolution of NSCLCs associated with cigarette smoking.