BACKGROUNDMultiple drug resistance is one of the important reasons that patients failed to chemotherapy and died of tumors. The aim of this study is to investigate the expression of resistance-related proteins, P-glycoprotein (P-gp), multidrug resistance-associated protein (MRP), lung resistance-related protein (LRP), topoisomerase II (Topo II) and glutathion-S-transferase-π (GST-π) in non-small cell lung cancer (NSCLC) tissues and their clinical significance.

METHODSExpression of P-gp, MRP, LRP, Topo II and GST-π was measured in 98 NSCLC tissues by immunohistochemistry SP method.

RESULTSThe positive rate of P-gp, MRP, LRP, Topo II and GST-π was 27.6%, 11.2%, 75.5%, 50.0% and 64.3% respectively. Significant relationship was observed between expression of LRP and TopoII and histological classification. No remarkable difference in expression of multiple drug resistance-related proteins was found among different TNM stages. A total of 47 patients with NSCLC were treated with chemotherapy. There was significant relationship between expression of P-gp, LRP and GST-π and chemotherapy response (P < 0.05).

CONCLUSIONSNSCLC has overexpression of multiple drug resistance-related proteins. Combined detection of these proteins may be useful to guide chemotherapy and predict the response for lung cancer.