title: [The paradox of polyomaviruses. Lytic infection or tumor induction?].
abstract: Murine polyomaviruses can produce lytic infections in mouse cell cultures or transform in vitro rat fibroblasts through a complex interaction with key cellular regulators. After infection of newborn mice, some strains of polyomavirus induce epithelial and mesenchymal tumors. It has been described that there is a direct relationship between viral dissemination in the mouse and tumor induction. However, at a single cell level lytic infection and transformation would not be able to coexist. The existence of 3 distinct cell populations in polyoma-induced tumors, classified according to the presence or absence of viral DNA and viral capsid protein VP-1 have been described. We have reported a fourth type of cell in the neoplasms, that can express the early and the late viral genes but do not allow virus assembly, probably due to underphosphorylation of VP-1. The mechanisms of polyoma intracellular migration and dissemination in the mouse are discussed, related to the virus' ability of tumor induction.
authors.affiliation: Laboratorio de Patología Experimental, Departamento de Microbiología, Facultad de Medicina, Universidad de Buenos Aires, Paraguay 2155, 1121 Buenos Aires, Argentina. patoexpe@fmed.uba.ar
authors.forename: Norberto A
authors.initials: NA
authors.lastname: Sanjuan
mesh_terms: D000818:Animals; D002213:Capsid; D004279:DNA, Viral / Q000032:analysis / Q000235:genetics; D004195:Disease Models, Animal; D051379:Mice; D011120:Polyomavirus / Q000472:pathogenicity*; D027601:Polyomavirus Infections / Q000473:pathology / Q000821:virology*; D051381:Rats; D014412:Tumor Virus Infections / Q000473:pathology / Q000821:virology*; D014779:Virus Replication
chemical_list: D004279:DNA, Viral