Prognostic value of the expression of p53, bcl-2, and bax oncoproteins, and neovascularization in patients with radically resected non-small-cell lung cancer.

PURPOSE

To assess the prognostic value of p53, bcl-2, bax, and neovascularization in radically resected non-small-cell lung cancer (NSCLC) patients.

PATIENTS AND METHODS

Tumors from 116 patients were assessed by immunohistochemistry for expression of p53 (DO7 and PAb1081), bcl-2, and the quantification of microvessel density (CD-31). In addition, the expression of bax was assessed in 61 stage I tumors. The median levels of expression of each marker were used as cutoff points.

RESULTS

p53 was not correlated to any patient or tumor characteristic, whereas bcl-2 showed higher expression in squamous cell carcinomas (P < .001). bax expression was significantly related with male sex (P = .006) and adenocarcinoma type (P = .0013). p53 status, assessed with one monoclonal antibody (MoAb), was not predictive for survival; however, the combination of staining results obtained with two MoAbs identified the DO7-/PAb1801+ tumors as those with the worst prognosis. bcl-2 expression was associated with longer survival in stage I patients (P = .0169). The combined group expressing p53+(PAb1801)/bcl-2- had the worst survival in stage I patients (P = .034) and in the whole series in comparison with the other combinations of the two oncoproteins. bax expression alone had no influence on survival of stage I patients, but patients with bax+/bcl-2- tumors had the worst prognosis (P = .02 in comparison with bax+/bcl-2+). Tumor neovascularization was not related with other factors, and patients with CD-31+ tumors had a shorter survival duration than those with CD-31- tumors only in stage II (P = .0283). By multivariate analysis including all patients, the presence of p53+/ bcl-2- tumor expression and large tumor diameter (> or = 4cm) were independent prognostic factors for shorter survival duration. For stage I, only the presence of bax+/ bcl-2- tumor expression had a significant negative influence on survival.

CONCLUSION

The interaction and the regulation of new biologic markers, such as those involved in the apoptotic pathway, are complex. Combinations of the expression of several of them may give more valuable information than the study of just one. Prognostic influence of p53 staining varied depending on the choice of antibody and the combination of bcl-2- together with p53+ (PAb1801) or with bax+ had the worst influence on survival for patients with stage I NSCLC.