tetrahydrouridine has been researched along with Leukemia--Promyelocytic--Acute* in 3 studies
3 other study(ies) available for tetrahydrouridine and Leukemia--Promyelocytic--Acute
| Article | Year |
|---|---|
Biochemical mechanisms by which reutilization of DNA 5-methylcytosine is prevented in human cells.
The salvage metabolism of 5-methyldeoxycytidine 5'-monophosphate (5MedCMP) was studied in human promyelocytic leukemia (HL-60) cells and in PHA-stimulated human lymphocytes. To this end [5'-32P]5MedCMP was synthesized by a novel postlabeling procedure. At low substrate concentrations (less than 100 microM), the enzyme(s) present in crude HL-60 whole-cell extract deaminated 5MedCMP faster than they did dCMP. Although the phosphorylation of dCMP to dCDP was easily demonstrable with both kinds of cell extracts, no phosphorylation of 5MedCMP to 5MedCDP (5-methyldeoxycytidine 5'-diphosphate) was observed. This phenomenon was confirmed using HL-60 cells made permeable to nucleotides with Tween 80. In view of the substantial 5MeCyt (5-methylcytosine) content of DNA and the degradation of DNA that occurs in cells, it is conceivable that 5MedCyd (5-methyl-2'-deoxycytidine) and 5MedCMP are available for reutilization in DNA synthesis. This would have devastating effects on cellular control and gene expression. The results of the present investigation indicate that rapid deamination at the monophosphate level and, in particular, stringent discrimination of 5MedCMP by cellular monophosphokinase(s) are the key mechanisms by which reutilization of DNA 5MeCyt is prevented in human hematopoietic cells. Topics: 5-Methylcytosine; Cell Extracts; Cells, Cultured; Chromatography, Thin Layer; Cytosine; DCMP Deaminase; Deoxycytidine Monophosphate; DNA; Humans; Kinetics; Leukemia, Promyelocytic, Acute; Lymphocytes; Methylation; Nucleoside-Phosphate Kinase; Phosphorylation; Tetrahydrouridine; Tumor Cells, Cultured | 1991 |
The impact of selected nucleosides on the cytotoxicity of Ara-C in HL60 cells.
Topics: Cell Line; Cell Survival; Cytarabine; Cytidine; Deoxyadenosines; Deoxycytidine; Deoxyguanosine; Drug Interactions; Humans; Kinetics; Leukemia, Promyelocytic, Acute; Nucleosides; Tetrahydrouridine; Uridine | 1991 |
Reduction of ara-C cytotoxicity in HL 60 cells by addition of deoxycytidine, cytidine or increased level of cytidine deaminase.
Topics: Bone Marrow; Bone Marrow Cells; Cell Division; Cytarabine; Cytidine; Cytidine Deaminase; Deoxycytidine; Deoxycytidine Kinase; Humans; Leukemia, Promyelocytic, Acute; Nucleoside Deaminases; Phosphotransferases; Tetrahydrouridine; Tretinoin; Tumor Cells, Cultured | 1989 |