title: Cellular ras gene activity is required for full neoplastic transformation by the large tumor antigen of SV40.
abstract: To investigate the role of the cellular ras gene product in neoplastic transformation by the SV40 large tumor antigen (SVLT), murine C3H10T1/2 cells were rendered deficient in Ras activity by transfection with inducible or constitutive antisense ras gene constructs or through the introduction of the dominant-negative mutant, ras(asn17). Consistent with previous results, SVLT-induced morphological transformation was unaffected by the down-regulation of c-ras gene product activity. On the other hand, colony formation in soft agar and tumorigenicity in nude mice were drastically reduced in c-Ras-deficient cells. In addition, SVLT expression in C3H10T1/2 cells led to increased c-Ras activity, as determined by an increase in the Ras-bound GTP/GTP + GDP ratio. These results suggest that c-Ras is required for full neoplastic transformation by SVLT.
authors.affiliation: Department of Microbiology and Immunology, Queen's University, Kingston, Ontario, Canada. raptisl@post.queensu.ca
authors.forename: L
authors.initials: L
authors.lastname: Raptis
authors.forename: H L
authors.initials: HL
authors.lastname: Brownell
authors.forename: M J
authors.initials: MJ
authors.lastname: Corbley
authors.forename: K W
authors.initials: KW
authors.lastname: Wood
authors.forename: D
authors.initials: D
authors.lastname: Wang
authors.forename: T
authors.initials: T
authors.lastname: Haliotis
mesh_terms: D000818:Animals; D000952:Antigens, Polyomavirus Transforming / Q000502:physiology*; D002461:Cell Line, Transformed; D002471:Cell Transformation, Neoplastic / Q000235:genetics*; D005347:Fibroblasts; D015972:Gene Expression Regulation, Neoplastic; D011905:Genes, ras / Q000235:genetics / Q000502:physiology*; D006153:Guanosine Diphosphate / Q000378:metabolism; D006160:Guanosine Triphosphate / Q000378:metabolism; D051379:Mice; D008819:Mice, Nude; D009154:Mutation; D009374:Neoplasms, Experimental / Q000235:genetics; D027384:Oncogene Proteins v-raf; D016372:RNA, Antisense; D015682:Retroviridae Proteins, Oncogenic / Q000235:genetics; D013539:Simian virus 40 / Q000276:immunology*; D014162:Transfection; D018631:ras Proteins / Q000032:analysis / Q000378:metabolism
chemical_list: D000952:Antigens, Polyomavirus Transforming; D016372:RNA, Antisense; D015682:Retroviridae Proteins, Oncogenic; D006153:Guanosine Diphosphate; D006160:Guanosine Triphosphate; D027384:Oncogene Proteins v-raf; D018631:ras Proteins