Immunohistochemical Study of Bcl-2 Protein, Apoptosis and p53 Protein Expression in Non-small Cell Lung Cancer

Abstract

We investigated the expression ofBcl-2 protein, apoptosis and p53 protein immunohistochemically in resected non-small cell lung cancer.Bcl-2 protein was expressed in 24% of squamous cell carcinoma (SQ), 17% of adenocarcinoma (AD), and 17% of large cell carcinoma (LA). The staining with Apop Tag was positive in 35% of SQ, 27% of AD, and 25% of LA. p53 protein was detected in 42% of SQ, 20% of AD, and 42% of LA. In squamous cell carcinoma, the expressions ofBcl-2 protein, Apop Tag and p53 protein were higher than in other histologic types. The survival rate of patients with resectedBcl-2-positive carcinoma was higher than those with resectedBcl -2-negative carcinoma (95.5% vs. 81.4%). The expression ofBcl-2 protein was higher in stage I lung carcinoma than in others. The expression of p53 protein was higher inBcl-2 protein positive tumors than inBcl-2 protein negative tumors (p=0.06). The expression of Apop Tag was significantly higher inBcl-2 protein and p53 protein-positive tumors than in Bcl-2 protein-negative and/or p53 protein-negative tumors (p=0.018).