Direct determination of intracellular daunorubicin in intact confluent monolayers of AT1 prostate carcinoma cells using a multiwell-multilabel counter.
The cytostatic drug daunorubicin exerts its toxic action by intercalating into the DNA. The efficacy of daunorubicin depends on the intracellular amount in the tumor cell. Here we have evaluated the use of a multiwell-multilabel reader for the direct determination of the fluorescent cytostatic drug daunorubicin in a prostate carcinoma cell line (AT1 R-3327 Dunning prostate carcinoma cells) grown on 24-well plates. We present evidence that this simple fluorescent parameter is a good measure for the toxicologically relevant amount of the drug intercalated into the DNA and, therefore, is a good predictor for the drug's cytotoxicity. The amount of cationic cytostatics in a tumor cell is primarily a function of the efflux pump protein p-gycoprotein (pGP). Therefore, it is of great value that the assay is also suitable for the estimation of the multidrug resistance efflux pump (pGP) activity.
Sauvant
C
C
Physiologisches Institut, Universität Würzburg, 97070 Würzburg, Germany. christoph.sauvant@mail.uni-wuerzburg.de <christoph.sauvant@mail.uni-wuerzburg.de>
Thews
O
O
Wirth
C
C
Gekle
M
M
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000378:metabolism; D000818:Animals; D002457:Cell Extracts; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D002623:Chemistry Techniques, Analytical / Q000295:instrumentation* / Q000379:methods*; D004273:DNA, Neoplasm / Q000378:metabolism; D003630:Daunorubicin / Q000032:analysis*; D042541:Intracellular Space / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D011471:Prostatic Neoplasms / Q000737:chemistry*; D051381:Rats; D013050:Spectrometry, Fluorescence; D013347:Subcellular Fractions; D013997:Time Factors; D014700:Verapamil / Q000494:pharmacology
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D002457:Cell Extracts; D004273:DNA, Neoplasm; D014700:Verapamil; D003630:Daunorubicin