In the present study we have used beef heart submitochondrial preparations (BH-SMP) to demonstrate that a component of mitochondrial Complex I, probably the NADH dehydrogenase flavin, is the mitochondrial site of anthracycline reduction. During forward electron transport, the anthracyclines doxorubicin (Adriamycin) and daunorubicin acted as one-electron acceptors for BH-SMP (i.e. were reduced t...

The selection pressure for resistance to chemotherapy is accompanied by the enhanced expression of ABC proteins and increased cellular glycosphingolipid content. Thus, a possible connection between glycosphingolipid metabolism and ABC proteins in drug resistance has been suggested. In the present study, we established two human multidrug-resistant (MDR) cell lines derived from MESSA sarcoma cel...

Haem oxygenase-1 (HO-1) is increasingly regarded as a pro-tumoral target in the treatment of human cancers. Currently, little is known about HO-1 and its role in human acute myeloid leukaemia (AML) to regulate apoptosis in response to chemotherapy. Recently, we showed that HO-1 protects AML samples from tumour necrosis factor-α (TNF)-induced apoptosis - it being regulated by transcription facto...

The starter unit used in the biosynthesis of daunorubicin is propionyl coenzyme A (CoA) rather than acetyl-CoA, which is used in the production of most of the bacterial aromatic polyketides studied to date. In the daunorubicin biosynthesis gene cluster of Streptomyces peucetius, directly downstream of the genes encoding the beta-ketoacyl:acyl carrier protein synthase subunits, are two genes, dp...

BACKGROUND Many dihydropyridine analogues with calcium channel blocker activity are able to reverse multidrug resistance (MDR). We studied the daunorubicin resistance reversing activity of the R enantiomer (GR66234A) and the L-enantiomer (GR66235 A) of teludipine, a new lipophilic calcium channel blocker synthesized by Glaxo. METHODS The daunorubicin resistance reversing activity of the enant...

The U-A10 cell line, a doxorubicin-selected variant of human U-937 myeloid leukemia cells, exhibits a redistribution of anthracyclines into a expanded vesicular compartment. The acidic nature of this compartment was confirmed by vital staining with a pH sensitive dye, LysoSensor yellow/blue DND-160. Identification of the vesicular compartment was performed by immunofluorescence analysis. Staini...

The efficacy of the addition of intensive therapy with daunorubicin (45 mg/m2 IV on days 1, 2, 3) to an otherwise identical induction program consisting of vincristine, prednisone, and L-asparaginase was assessed in 177 previously untreated adults (greater than or equal to 20 years of age) with acute lymphocytic leukemia (ALL). In the prospectively randomized phase of the investigation, 46 pati...

It has recently been shown that anthracycline antibiotic-resistant tumor cells are less responsive to daunorubicin-stimulated B23 nucleolar phosphoprotein translocation than drug-sensitive cells. Since cyclosporin A and verapamil reverse primary acquired and secondary cross-resistance to daunorubicin, we investigated the effect of these agents on nucleolar B23 translocation in sensitive and res...

-The clinical efficacy of anthracycline antineoplastic agents is limited by a high incidence of severe and usually irreversible cardiac toxicity, the cause of which remains controversial. In primary cultures of neonatal and adult rat ventricular myocytes, we found that daunorubicin, at concentrations </=1 micromol/L, induced myocyte programmed cell death within 24 hours, as defined by several c...