ABSTRACT
Background and purpose:Resistance to anticarcinogen is one of the key factors that affect the treatment efficiency in lung cancer. The purpose of this study was to investigate the clinical significance of the multidurg resistance-related proteins P-gp, multidrug resistance-related proteins(MRP),lung resistance associated protien(LRP) and GST-?by detecting their expression in lung cancer and to investigate the mechanism of resistance to anticarcinogen. Methods:S-P immunohistochemistry was used to examine the expression level of proteins P-gp, MRP, LRP and GST- ?in 226 samples of lung cancer and 23 samples of normal lung tissues. Results:The positive rates of P-gp, MRP, LRP and GST-? in lung cancers were 46.0%, 42.0%, 54.4%, 62.4% respectively. Significant difference existed between tumorous tissue and normal lung tissue (17.4%, 13.0%, 17.4%, 21.7%). The positive rates of P-gp, MRP, LRP and GST-? in poorly differentiated-type of NSCLC were 33.3%, 22.8%, 33.3%, 47.4%, compared with differentiated-type of NSCLC (59.7%, 58.1%, 73.6%, 79.1%) (P