Expresión de proteínas relacionadas con resistencia a múltiples drogas (MDR-proteínas) y resistencia a la quimioterapia en el cáncer de pulmón

purpose: to evaluate the expression of mdr-proteins in the response to lung cancer chemotherapy. methods: 147 tumor samples were collected from 143 patients, 35 of which were obtained by bronchoscopy and 112 from surgery; 101 samples belonging to 99 patients were considered valid for the study. the samples were cryopreserved and immunochemistry with monoclonal murine antibodies used to determine the mdr-proteins pgp, mrp1 and lrp. results: no mdr-proteins were expressed in 16 cases. one mdr-protein was present in 32 cases: pgp in 3, mrp1 in 11 and lrp in 18. two mdr-proteins were expressed in 34 cases: pgp and lrp in 24, mrp1 and pgp in 5, and mrp and lrp in 5. all the three mdr-proteins were present in 17 cases. no differences were observed considering age (pgp, p = 0.74; mrp1, p = 0.95; lrp, p = 0.26). neither sex produced changes when considering either number of mdr-proteins (p = 0.55) or types of them (p = 0.21). significant differences of mrd-proteins were also lacking for number (p = 0.59) and type (p = 0.51) in relation to the tumor histologic grade. the tendency to the simultaneous expression of pgp and lrp was very significant (p < 0.01), while the simultaneous expression of mrp1 and lrp showed to be no significant (p = 0.26). conclussions: pgp and lrp are frequently expressed simultaneously. only the expression of pgp and the number of mdr-proteins expressed simultaneously seem to be related to response to chemotherapy.