Prognostic value of immunohistochemical expression of p53, bax, Bcl-2 and Bcl-xL in resected non-small-cell lung cancers

Aims: Some experimental evidence suggests that in lung cancer, development, progression and an increased proliferation rate can be linked to apoptosis-related factors. In this study we evaluated the possible role of p53 and Bcl-2 gene family members as prognostic factors for non-small-cell lung cancer. Methods and results: We investigated the immunohistochemical expression of p53 and Bcl-2 gene family members (bax, Bcl-2 and Bcl-x(L)) in 94 non-small-cell lung cancer specimens to establish the role of these genes in lung cancer pathogenesis, and to evaluate their prognostic importance. The expression of Bcl-2 was correlated with a shorter patient survival time and with the nodal status of the neoplasm. We also found frequent over-expression of bax and Bcl-x(L) to be of no prognostic significance. Finally, we found no correlation between frequent detection of aberrant p53 protein and expression of either Bcl-2, bax or Bcl-x(L) or with patient survival time. Conclusions: This study confirms a relevant role for apoptosis-regulatory proteins in the pathogenesis of lung cancer, and highlights the possible role of Bcl-2 as a prognostic factor for this tumour.