title: Multidrug-resistance gene (mdr1) expression in human tumor xenografts.
abstract: We examined the expression of human multidrug resistance gene (MDR1); 13 of 34 xenografts showed various MDR1 gene transcript levels by reverse transcriptase-polymerase chain reaction. MDR1 was detected in 3 of 10 lung, 5 of 8 gastric, 3 of 3 colon and 2 of 3 pancreatic cancers, but not in 4 breast cancers, or 6 gliomas. We evaluated drug-sensitivity of xenografts in vivo; 28 of 34 xenografts showed drug resistance to vincristine and/or doxorubicin, whereas 13 of 28 drug-resistant xenografts expressed MDR1. The expression of MDR1 may explain the intrinsic drug resistance in certain xenografts.
authors.affiliation: TOKAI UNIV,SCH MED,DEPT PATHOL,ISEHARA,KANAGAWA 25911,JAPAN. CENT INST EXPTL ANIM,KAWASAKI,KANAGAWA 213,JAPAN. JAPANESE FDN CANC RES,CTR CANC CHEMOTHERAPY,TOSHIMA KU,TOKYO 170,JAPAN. KANAGAWA ACAD SCI & TECHNOL,KAWASAKI,KANAGAWA 213,JAPAN.
authors.forename: Y
authors.initials: Y
authors.lastname: Abe
authors.forename: M
authors.initials: M
authors.lastname: Nakamura
authors.forename: Y
authors.initials: Y
authors.lastname: Ohnishi
authors.forename: M
authors.initials: M
authors.lastname: Inaba
authors.forename: Y
authors.initials: Y
authors.lastname: Ueyama
authors.forename: N
authors.initials: N
authors.lastname: Tamaoka