ANTIPROLIFERATIVE EFFECTS AND DNA HYPOMETHYLATION BY 5-AZA-2'-DEOXYCYTIDINE IN HUMAN NEUROBLASTOMA CELL-LINES

5-Aza-2'-deoxycytidine (5-AZA-CdR) is an inhibitor of DNA methylation, and its antileukemic activity has been shown in preclinical and clini cal studies. This paper describes the ability of 5-AZA-CdR to inhibit DNA methylation, DNA synthesis and cell growth in several human neurob lastoma cell lines. The stability of cell growth inhibition was ascert ained, as well as the ability of the metabolite thymidine to enhance t he antiproliferative effect of 5-AZA-CdR. The activity of phosphorylat ing enzyme deoxycytidine kinase (dCK) was correlated to different leve ls of sensitivity in several cell lines. The results obtained indicate that 5-AZA-CdR may be an agent for the chemotherapy of neuroblastoma.