ASBESTOS, SIMIAN-VIRUS-40 AND MALIGNANT MESOTHELIOMA

Background. DNA sequences and immunoreactivity associated with Simian Virus 40 transforming factors, large T and small t antigens (SV40LTAg) , suggestive of an aetiopathogenetic link have been identified in fres h frozen tissue of a high proportion of recent cases of pleural mesoth eliomas from the United States, Italy and Germany. SV40 is not normall y infective in man though it can transform human.-cells in tissue cult ure. A large cohort of people in the western world was accidentally pa renterally inoculated ; with live SV40 through contaminated polio vacc ines given between 1959 and 1961, and this might be a factor in the cu rrent continuing rise in the incidence of mesothelioma in the United S tates, Britain and Europe. The present study investigated the presence of SV40LTAg DNA in recently diagnosed cases of mesothelioma in Britai n and the feasibility of detecting the SV40 DNA in archival tissue for retrospective analysis of cases in the peri-vaccination period. Metho ds. DNA was extracted from fresh frozen and/or rehydrated formalin fix ed, paraffin embedded tissue sections from nine recently diagnosed cas es of mesothelioma, nine cases of pulmonary adenocarcinoma, and three reactive pleurae, and amplified by the polymerase chain reaction (PCR) using the primer pairs used previously on fresh frozen tissues - name ly, the SV primer set directed at the LTAg gene sequence unique to SV4 0 and the PYV primer set directed at a sequence shared by SV40 and pap ovavirus strains BK and IC, respectively. Results. PCR positivity with the SV primer set was restricted to four of the nine cases of mesothe lioma. in contrast, six of the nine mesotheliomas, two of the nine ade nocarcinomas, and one of the three reactive pleurae showed positivity with the PYV primers. The fresh frozen and corresponding formalin fixe d, paraffin embedded tissue results concorded well with each other. Co nclusions. Our data provide evidence for the association of SV40LTAg p rimer specific DNA with human pulmonary mesothelioma in the British po pulation.