Positive Correlation between Cyclooxygenase 2 and the Expression of ABC Transporters in Non-small Cell Lung Cancer

Abstract

Background: The primary method of treatment of non-small cell lung cancer (NSCLC) in stage IIIB and IV is chemotherapy. Previous data suggested a correlation between cyclooxygenase-2 (COX-2) expression and the multidrug-resistant phenotype of cancer cells. Materials and Methods: In this prospective study, 32 patients with NSCLC in stage IIIB and IV from 1,078 patients were included. The expression of COX-2 as well as the expression of the ABC transporters MDR1/P-glycoprotein (MDR1/P-gp), BCRP and MRP1 were detected immunohistochemically. Results: Univariate and multivariate analyses demonstrated no prognostic or predictive significance of these proteins. It was merely demonstrated that complete or partial response are favourable factors for prediction of longer progression-free survival time. However, a strong positive correlation between the expression of COX-2, MDR1/P-gp and BCRP was found in NSCLC. Conclusion: These data suggest no clinical impact for the expression of MDR1/P-gp, MRP1, BCRP or COX-2 in NSCLC, but a putative coregulation of COX-2 and MDR1/P-gp and BCRP in NSCLC.