title: In vitro cytotoxicity of hexamethylmelamine (HMM) and its derivatives.
abstract: The cytotoxicity of hexamethylmelamine (HMM) and its metabolites was investigated in three murine cell lines: one in vitro naturally sensitive to HMM (RC) and two in vivo naturally resistant (P388 and P388D1). The percentage of viable cells was determined both by the in situ reduction of a tetrazolium salt (MTT assay) and by the uptake of labelled thymidine into DNA (3HTdR assay). Short (1h) and long (48h) exposures of cells to drugs were considered. In all experimental conditions used, HMM was found to be inactive, whereas its hydroxylated metabolite hydroxymethylpentamethylmelamine (HMPMM) and one analog N, N 'dihydroxymethyltetramethylmelamine (DHTMM) were found to be cytotoxic. The results further indicated that HMM must be metabolized before it can exert its cytotoxic effect. The activity of HMPMM and DHTMM was found unlikely to be related to extracellular or intracellular release of formaldehyde.
authors.affiliation: Unité de Toxicologie et de Chimie Bioanalytique, Université Libre de Bruxelles, Belgium.
authors.forename: J
authors.initials: J
authors.lastname: Dubois
authors.forename: R
authors.initials: R
authors.lastname: Arnould
authors.forename: F
authors.initials: F
authors.lastname: Abikhalil
authors.forename: M
authors.initials: M
authors.lastname: Hanocq
authors.forename: G
authors.initials: G
authors.lastname: Atassi
authors.forename: G
authors.initials: G
authors.lastname: Ghanem
authors.forename: A
authors.initials: A
authors.lastname: Libert
authors.forename: F J
authors.initials: FJ
authors.lastname: Lejeune
mesh_terms: D006585:Altretamine / Q000031:analogs & derivatives / Q000494:pharmacology*; D000818:Animals; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects*; D004261:DNA Replication / Q000187:drug effects; D051379:Mice; D013329:Structure-Activity Relationship; D013936:Thymidine / Q000378:metabolism; D014227:Triazines / Q000494:pharmacology*; D014316:Tritium; D014407:Tumor Cells, Cultured / Q000166:cytology / Q000187:drug effects
chemical_list: D014227:Triazines; D014316:Tritium; D006585:Altretamine; D013936:Thymidine