ISSN:
1434-0879
Schlagwort(e):
Bladder cancer
;
Doxorubicin
;
Multidrug resistance
;
P-170 glycoprotein
;
Rhodamine 123
;
R-verapamil
Quelle:
Springer Online Journal Archives 1860-2000
Thema:
Medizin
Notizen:
Abstract A doxorubicin-resistant human bladder carcinoma cell line RT112/D21 was established by continuous exposure of the parental line RT112 to increasing concentrations of doxorubicin over a period of 9 months. RT112/D21 cells expressed significantly more P-170 glycoprotein than the parental line, and rhodamine 123 efflux, as a functional parameter of P-170 glycoprotein activity, was increased. RT112/D21 cells were 96 times more resistant to doxorubicin than RT112 cells, and crossresistance to epirubicin and vinblastine was present. Sensitivity to methotrexate and mitomycin C remained unchanged. R-verapamil reversed resistance to doxorubicin, epirubicin and vinblastine in RT112/D21 cells but did not affect sensitivity to methotrexate and mitomycin C. In RT112 cells, R-verapamil had no effect on drug sensitivity. Thus, it may be assumed that primary or induced MDR1 gene-encoded P-170 glycoprotein expression is a relevant mechanism of chemoresistance in transitional cell carcinoma, and that chemotherapeutic strategies in combination with chemosensitizers improve response rates.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1007/BF00296874
Permalink
