Molecular characterization of SV40 DNA in multiple samples from a human mesothelioma

Background: Prolonged exposure to asbestos, a potent carcinogen, has been t he generally accepted factor responsible for the development of human mesot heliomas. Recent reports documenting the detection of SV40 DNA in human mes otheliomas suggest the possibility that this known tumor virus may be an ad ditional factor involved in the development of some tumors. Methods: A deta iled analysis was performed by polymerase chain reaction and DNA sequencing of the genetic characteristics of SV40 vital DNA detected in samples taken from multiple sites of a human mesothelioma. Results: A single virus varia nt was detected within the tumor that encoded a novel variable region at th e C-terminus of the large T-antigen oncoprotein. The viral regulatory regio n was predominantly archetypal in sequence (lacking duplications of the enh ancer), typical of natural isolates. Conclusions: These data confirm previo us reports from several laboratories showing an association of SV40 DNA wit h human mesotheliomas and provide the first evidence of a novel virus varia nt present in separated regions of a mesothelioma.