Clinical Significance on Pathological Detection of Multidrug Resistance in Non-small Cell Lung Cancer

Objective 　To evaluate the expressions of GST-π, LRP, Topo Ⅱa, MRP and MDR in 113 non-small cell lung cancer (NSCLC), to observe their relationships with clinicopathologic characterization of cancer and their interactions. Methods 　Expressions of GST-π, LRP and Topo Ⅱa were detected by S-P immunohistochemistry, and expressions of MRP, MDR₁ mRNA in paraffin-embedded cancer tissues were detected by in situ hybridization. Results 　(1) The positive rates of GST-π, LRP, Topo Ⅱa and MRP, MDR₁ mRNA were 75. 2 %, 80. 5 %, 60. 2 %, 79. 6 % and 51. 3 % in NSCLC, respectively. (2) The expressions of LRP, Topo Ⅱa, MRP had a close relationship with the histological types in NSCLC, respectively. (3) There were significant relationships between positive rates of GST-π and MRP ( P <0. 05), LRP and MRP( P < 0. 01), MDR₁ and MRP ( P < 0. 01), respectively. Conclusion 　(1) The overexpressions and interactions of GST-π, LRP, Topo Ⅱa, MRP and MDR are important causes of primary MDR in NSCLC. (2) The overexpressions of LRP and MRP, the overexpression of Topo Ⅱa and the reduced expression of MRP, which are related with the chemotherapeutic sensitivity in adenocarcinoma and squamous carcinoma, respectively.