title: Changes of DNA methylation in protooncogenes in the process of radiation-induced transformation of mouse m5S/1M cells in vitro.
abstract: To assess the importance of changes in DNA methylation in an X-ray-induced cellular transformation process, methylation patterns of five nuclear protooncogenes in fifteen transformant clones were studied and compared to that of the parental non-transformed cell line m5S/1M. All transformants examined revealed an alteration in DNA methylation in some of the genes, although these changes were variable among them. A comparison of cellular characteristics with corresponding DNA methylation changes in different clones suggested that the loss of contact inhibition and the gain of anchorage independency were associated with increases of methylation in many genes, whereas the acquisition of tumorigenicity was often accompanied by a decrease of methylation in the N-myc and c-myc genes. Resultant data indicate that the alteration of DNA methylation is closely related to transformation process, yet how this involvement occurs is complex and remains unclear.
authors: Department of Analytical Chemistry, Kyoto Pharmaceutical University, Japan.
authors: K
authors: K
authors: Yasuzawa
authors: S
authors: S
authors: Kodama
authors: M
authors: M
authors: Kato
authors: Y
authors: Y
authors: Uehara
authors: R
authors: R
authors: Tawa
authors: S
authors: S
authors: Hirose
authors: M S
authors: MS
authors: Sasaki
authors: S
authors: S
authors: Okada
authors: T
authors: T
authors: Ono
mesh_terms: D000818:Animals; D015139:Blotting, Southern; D002461:Cell Line, Transformed; D002471:Cell Transformation, Neoplastic / Q000235:genetics*; D004247:DNA / Q000378:metabolism* / Q000528:radiation effects; D008745:Methylation / Q000528:radiation effects; D051379:Mice; D011519:Proto-Oncogenes / Q000235:genetics* / Q000528:radiation effects
chemical_list: D004247:DNA