The Study on Expression of Multidrug Resistance-Associated Protein and Its Relation With Prognosis in Non-Small Cell Lung Cancer

Objective: This paper was to explore the relationships between expression of multidrug resistance associated protein (MRP) and clinicopathological parameters and prognosis. Methods: We detected the expression of MRP by using method of immunohistochemistry in 62 patients with non small cell lung cancer (NSCLC). Results: Our study of tumor tissue confirmed the plasma membrane or cytoplasm locations of the MRP. We found that the majority (83.88%) patients with NSCLC had detectable levels of MRP, and strong MRP expression was detected in 46.77% patients. But no potentially confounding correlation was observed between MRP expression and any clinicopathological parameters examined, including sex, histological type, tumor cell differentiation, lymphatic metastasis (P0.05). The mean survival period of the patients with MRP negative expression was (69.81±17.41) months, and that of the patients with MRP positive expression was (25.38±4.46) months. Log rank test suggested that the difference between them was significant (P=0.0156). Furthermore, in squamous cell cancer we also found the statistically significant difference between the mean survival period of patients with MRP positive expression and those of patients with MRP negative expression (P=0.0153). Conclusion: High expression of MRP was predictive for worse survival, and it was a independent factor that affected prognosis. The mean survival period of patients with MRP negative expression was relative long.