Multi-drug resistance of a doxorubicin-resistant bladder cancer cell line.
A bladder tumor cell line resistant to doxorubicin (MGH-U1R) has been established previously by culturing a human transitional cell carcinoma cell line (MGH-U1) in increasing concentrations of the drug. MGH-U1R is 40 times more resistant to doxorubicin than MGH-U1. In the present study, MGH-U1R was evaluated for its multi-drug resistance or pleiotropism by testing against other chemotherapeutic agents. MGH-U1R was found to be 188 times more resistant to vinblastine and 13 times more resistant to etoposide than MGH-U1, while remained sensitive to bleomycin. Taken together with earlier evidence that the resistance of MGH-U1R to doxorubicin can be reversed by a calcium-channel blocker verapamil, and the measured over-expression of the mdr1 gene in these cells, MGH-U1R has the characteristic multiple drug resistance properties similar to other established doxorubicin resistant carcinoma cell lines. MGH-U1R may be a useful model for the development of strategies in overcoming drug-resistance in the treatment of transitional cell carcinoma.
Floyd
J W
JW
Urology Research Laboratory, Massachusetts General Hospital, Boston 02114.
Lin
C W
CW
Prout
G R
GR
D001761:Bleomycin / Q000494:pharmacology; D002470:Cell Survival / Q000187:drug effects; D004317:Doxorubicin / Q000494:pharmacology*; D004351:Drug Resistance; D005047:Etoposide / Q000494:pharmacology; D006801:Humans; D014407:Tumor Cells, Cultured / Q000187:drug effects*; D014410:Tumor Stem Cell Assay; D001749:Urinary Bladder Neoplasms / Q000473:pathology*; D014747:Vinblastine / Q000494:pharmacology
D001761:Bleomycin; D014747:Vinblastine; D005047:Etoposide; D004317:Doxorubicin