title: DNA damage and repair in L1210 cells exposed to 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea.
abstract: The DNA of L1210 cells exposed to low concentrations of 1-(2-chloroethyl)=3-cyclohexyl-1-nitrosourea has been analyzed for the presence of single-strand breaks. DNA from 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea-treated cells both sediments more slowly than control DNA on alkaline sucrose gradients andshows a greater extent of strand separation of the DNA helix in alkali. These effects are a typical result of exposure of cellular DNA to alkylating agents or ionizing radiation. The extent of DNA damage caused by 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea has been related to the same amount of damage resulting from exposure of cells to low doses of gamma-irradiation. The rate and extent of repair of 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea-induced damage is slow and incomplete, compared with the repair of gamma-irradiation damage to DNA. It is concluded that 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea behaves as a weak alkylating agent, a property that may explain its antitumor properties.
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D002499:Centrifugation, Density Gradient; D004260:DNA Repair / Q000187:drug effects* / Q000528:radiation effects; D004273:DNA, Neoplasm / Q000378:metabolism; D004277:DNA, Single-Stranded / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004307:Dose-Response Relationship, Radiation; D005720:Gamma Rays; D007939:Leukemia L1210 / Q000188:drug therapy* / Q000378:metabolism; D008130:Lomustine / Q000008:administration & dosage / Q000494:pharmacology*; D008297:Male; D051379:Mice; D008811:Mice, Inbred DBA; D009607:Nitrosourea Compounds / Q000494:pharmacology*
chemical_list: D004273:DNA, Neoplasm; D004277:DNA, Single-Stranded; D009607:Nitrosourea Compounds; D008130:Lomustine