Simian virus 40 detection in human mesothelioma: Reliability and significance of the available molecular evidence

Simian virus 40 was discovered as a contaminant of early poliovirus vaccine s that were inadvertently administered to millions of people in Europe and the United States between 1955 and 1963. Although SV40 was proven to be onc ogenic in rodents and capable of transforming human and animal cells in vit ro, its role in human cancer could not be proven epidemiologically. The mat ter was forgotten until 1993 when SV40 was accidentally found to cause meso theliomas in hamsters injected intra-cardially. Subsequently, DNA sequences associated with its powerful oncogenic principal, the large T antigen, wer e found with high frequency in human pleural mesothelioma using the polymer ase chain reaction (PCR). Since then many laboratories have confirmed the h uman findings. However, a few laboratories have failed to reproduce these d ata and the authors of the studies have claimed that the detection of SV40 DNA may simply represent PCR contamination artefacts. The controversy raise d by this viewpoint is reviewed in this article together with a critical ap praisal of the reliability of the molecular techniques used to detect SV40 DNA, in order to evaluate the potential aetiopathogenic role of SV40 in hum an mesothelioma.