title: Polyoma DNA replication dependent upon growth condition of SEWA sarcoma cells.
abstract: Extrachromosomal replication of viral DNA sequences has been observed in transformed as well as in normal cells following "stress"-inducing treatments. To explore the effect of growth conditions on the ability to support such replication, we analyzed SEWA sarcoma cells that grew subcutaneously or as ascites tumors in vivo as well as cell lines that were established from each of these tumors. The replicative form of polyoma DNA sequences was observed in SEWA tumors grown in ascites fluids but not in cells maintained as solid tumors. Polyoma DNA replication was found in ascites-derived cells that were adapted to grow in culture, only when the cultured cells are stimulated with UV irradiation. Immunoprecipitation of T antigens enabled detection of large T antigen only in the ascites-derived cells. The mechanisms that may regulate this phenomenon and the possible role large T may play in different growth conditions of SEWA cells are discussed.
authors.affiliation: Molecular Carcinogenesis Program, American Health Foundation, Valhalla, New York 10595.
authors.forename: R
authors.initials: R
authors.lastname: Robinson
authors.forename: Z
authors.initials: Z
authors.lastname: Ronai
mesh_terms: D000818:Animals; D000952:Antigens, Polyomavirus Transforming / Q000502:physiology; D015153:Blotting, Western; D002455:Cell Division; D002472:Cell Transformation, Viral; D004261:DNA Replication; D004279:DNA, Viral / Q000032:analysis; D005111:Extrachromosomal Inheritance; D005784:Gene Amplification; D051379:Mice; D011120:Polyomavirus / Q000235:genetics* / Q000276:immunology; D012513:Sarcoma, Experimental / Q000235:genetics* / Q000473:pathology; D013997:Time Factors; D014407:Tumor Cells, Cultured; D014779:Virus Replication
chemical_list: D000952:Antigens, Polyomavirus Transforming; D004279:DNA, Viral