title: Spontaneous, mutagen-induced and adenovirus-induced anchorage independent tumorigenic variants of mouse cells.
abstract: Normal C57 Black mouse embryo cells did not form colonies in agarose, but rare variant (ar+) cells able to grow in agarose were detected. Fluctuation analysis showed that ar+ variants arose by spontaneous mutation in the cultured cells. The frequency of ar+ variants was increased by treating cells with N-methyl-N'nitro-N-nitrosoguanidine or ethyl methane sulphonate, or by abortive infection by human adenovirus type 5. Induced ar+ cells were fibroblastic; most grew slowly and had slightly reduced saturation density and increased serum requirement, but formed colonies in agarose. Fourteen of twenty ar+ clones induced by Ad5 were T antigen negative and two of these were also negative when tested for viral DNA. Six clones contained a few cells that were T antigen positive when first tested, but were negative when retested later. The ar+ variants were tumorigenic in athymic and in normal syngeneic mice. The results suggest that the ar+ phenotype can arise by spontaneous or chemically-induced mutation, and can be induced by adenovirus by a process different from classical transformation.
mesh_terms: D000260:Adenoviruses, Human; D000818:Animals; D002455:Cell Division; D002460:Cell Line; D002471:Cell Transformation, Neoplastic; D002472:Cell Transformation, Viral; D002478:Cells, Cultured / Q000166:cytology*; D003470:Culture Media; D005020:Ethyl Methanesulfonate / Q000494:pharmacology; D005347:Fibroblasts; D014644:Genetic Variation; D008769:Methylnitronitrosoguanidine / Q000494:pharmacology; D051379:Mice; D009153:Mutagens / Q000494:pharmacology*; D009154:Mutation; D010641:Phenotype; D011134:Polysaccharides; D012685:Sepharose
chemical_list: D003470:Culture Media; D009153:Mutagens; D011134:Polysaccharides; D008769:Methylnitronitrosoguanidine; D012685:Sepharose; D005020:Ethyl Methanesulfonate