Expression of several resistance mechanisms in untreated human kidney and lung carcinomas.
Thirty human renal cell carcinomas and 94 non-small cell lung carcinomas of previously untreated patients were analyzed for the presence of P-glycoprotein, glutathione S-transferase-pi and topoisomerase II by means of immunohistochemistry. In the renal cell carcinomas investigated, two resistance markers were seen in 53% and three resistance markers in 36% of the cases. In only three tumors was one resistance mechanism observed. In the 94 non-small cell lung carcinomas 34% had two and 20% three resistance mechanisms, whereas 24% of the tumors revealed only one resistance mechanism. For determining the resistance of the tumors against drugs an in vitro short-term test was used. Only 12% of the sensitive lung tumors had more than one resistance mechanism, whereas 70% of the resistant tumors did. Thus a significant relationship exists between the resistance measured in vitro and the overexpression of P-glycoprotein or glutathione S-transferase-pi and the down-regulation of topoisomerase II.
German Cancer Research Center, Heidelberg.
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Volm
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Mattern
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Efferth
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Pommerenke
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D002289:Carcinoma, Non-Small-Cell Lung / Q000737:chemistry*; D002292:Carcinoma, Renal Cell / Q000737:chemistry*; D004250:DNA Topoisomerases, Type II / Q000032:analysis*; D004351:Drug Resistance; D005982:Glutathione Transferase / Q000032:analysis*; D006801:Humans; D007680:Kidney Neoplasms / Q000737:chemistry*; D008175:Lung Neoplasms / Q000737:chemistry*; D008562:Membrane Glycoproteins / Q000032:analysis*; D009363:Neoplasm Proteins / Q000032:analysis*
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D008562:Membrane Glycoproteins; D009363:Neoplasm Proteins; D005982:Glutathione Transferase; D004250:DNA Topoisomerases, Type II