title: Characterization of tumor cell lines from a spontaneous rat sarcoma expressing an endogenous retrovirus.
abstract: We have characterized various biologic, immunologic and growth properties of several cell lines established from a spontaneous rat sarcoma that was discovered more than 60 yr ago. The tumors consisted of mixed cell types with no detectable host cellular immune response. Cultures derived from single-cell clones of the parental cell line were non-invasive but highly tumorigenic even in adult rats. The cultured cells spontaneously released replication-competent endogenous rat type C virus which did not carry a transforming gene in its genome. Since normal cells from the same rat strain did not produce a retrovirus, it is possible that production of the endogenous retrovirus may have triggered specific cellular changes necessary for the oncogene expression and development of this tumor.
authors.forename: O E
authors.initials: OE
authors.lastname: Varnier
authors.forename: S P
authors.initials: SP
authors.lastname: Raffanti
authors.forename: O
authors.initials: O
authors.lastname: Muratore
authors.forename: C M
authors.initials: CM
authors.lastname: Repetto
authors.forename: P
authors.initials: P
authors.lastname: Pippia
authors.forename: G
authors.initials: G
authors.lastname: Tilloca
authors.forename: M A
authors.initials: MA
authors.lastname: Meloni
authors.forename: G
authors.initials: G
authors.lastname: Ivaldi
authors.forename: S
authors.initials: S
authors.lastname: Rasheed
mesh_terms: D000818:Animals; D002452:Cell Count; D002460:Cell Line; D005814:Genes, Viral; D009857:Oncogenes; D051381:Rats; D012190:Retroviridae / Q000235:genetics / Q000302:isolation & purification*; D012376:Rodent Diseases / Q000382:microbiology; D012509:Sarcoma / Q000382:microbiology* / Q000473:pathology / Q000662:veterinary; D014779:Virus Replication