Effects of induction of multi-drug resistance on accumulation of 99mTc-sestamibi in vitro.
The aim of our study was to evaluate the speed of induction of drug-resistance and its effects on intracellular MIBI accumulation in established human cell lines in-vitro. Four out of 5 cell lines were sensitive to vincristine, 1 cell line was vincristine-resistant. All vincristine sensitive cell lines became vincristine-resistant following drug exposure. Resistance in low-drug concentrations occurred as early as 24 hours after exposure and progressed to a roughly 1000-times enhanced resistance within 7 days. Induction of drug-resistance was associated with significantly decreased MIBI accumulation in 2 cell lines but was uneffected in 1 cell line, that was primarily drug sensitive as well as in one cell line that was primarily drug-resistant. Our data indicate, that induction of MDR is an extremely rapid process and the development of drug resistance is not always associated with enhanced MIBI extrusion.
Bender
H
H
Department of Nuclear Medicine, University Bonn, Germany. hbender@mailer.meb.uni-bonn.de
Friedrich
E
E
Zamora
P O
PO
Guhlke
S
S
Biersack
H J
HJ
D000970:Antineoplastic Agents / Q000633:toxicity; D001692:Biological Transport; D002455:Cell Division / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D004317:Doxorubicin / Q000633:toxicity; D018432:Drug Resistance, Multiple; D005260:Female; D005910:Glioma; D006801:Humans; D008297:Male; D010051:Ovarian Neoplasms; D011471:Prostatic Neoplasms; D017256:Technetium Tc 99m Sestamibi / Q000493:pharmacokinetics*; D014407:Tumor Cells, Cultured; D014750:Vincristine / Q000633:toxicity
D000970:Antineoplastic Agents; D014750:Vincristine; D004317:Doxorubicin; D017256:Technetium Tc 99m Sestamibi