Detection of SV40 T antigen genome in human gliomas.

The monkey polyomavirus simian virus 40 (SV40) has been reported to be associated with tumorigenesis of human neoplasms, mainly brain tumors. However, it remains controversial whether the virus really exists in human neoplasms and how the virus transforms human cells in vivo. We investigated the presence of SV40 T antigen genome in 33 human glioma tissue specimens from Japanese patients with different histopathologies by means of the polymerase chain reaction (PCR) followed by Southern blotting. The SV40 T antigen genome was amplified in 4 of the 13 ependymomas (31%) and 3 of the 20 other histotypes of gliomas (15%), whereas in the 22 nontumoral brain tissue specimens, only one case was found to be positive. DNA sequencing confirmed the PCR products to be those of SV40 T antigen. The findings thus suggest that the SV40 genome appears to exist in a certain population of brain tumors from Japanese patients, and that it may also play a role in the oncogenicity or maintenance of the transformed state.