SIMIAN-VIRUS 40-LIKE DNA-SEQUENCES IN HUMAN PLEURAL MESOTHELIOMA

Mesotheliomas are pleural, pericardial, or peritoneal neoplasms freque ntly associated with asbestos exposure, and it is estimated that over the next twenty years up to 80,000 new cases are expected in the USA a lone. We found simian virus 40-like DNA sequences in 29 of 48 mesothel iomas studied (60%) and demonstrated simian virus large-T antigen expr ession in 13 of 16 specimens. The matching lung samples did not contai n simian virus 40-like sequences; however, they contained asbestos. Th ese findings are to our knowledge the first demonstration of a physica l link between DNA viruslike sequences and human mesothelioma. We sugg est that a simian virus 40-like virus may act independently or as a co -carcinogen with asbestos. Moreover, the selective large T antigen exp ression by mesothelioma and not by the surrounding pulmonary parenchym a may have both diagnostic and therapeutic implications.