Related Experiment Videos
Detection of simian virus 40 DNA sequence in human primary glioblastomas multiforme
T Kouhata1, K Fukuyama, N Hagihara
1Department of Neurosurgery, Saga Medical School, Japan.
Object:
Deoxyribonucleic acid oncoviruses can induce neoplastic transformation of cells because their viral proteins interfere with antiproliferative cellular proteins. Simian virus 40 (SV40) is a DNA virus that induces the emergence of ependymomas, choroid plexus tumors, mesotheliomas, osteosarcomas, sarcomas, and various tumors when injected into newborn hamsters. Recently, approximately 60% of human ependymomas, choroid plexus tumors, and mesotheliomas were reported to contain and express SV40 DNA sequences. In this study the presence of SV40 DNA sequences was investigated in human brain tumors.
Methods:
Three of 32 glioblastomas mutiforme (GBMs), but none of two ependymomas and five medulloblastomas, were found to possess SV40 DNA sequences when examined using polymerase chain reaction (PCR). The DNA sequence analysis of PCR-amplified fragments disclosed that the samples were identical to the regulatory region of SV40. All three GBMs, which arose in elderly patients with wild-type p53, were considered to be primary (de novo) tumors. Although each of the three tumors was immunohistochemically negative for SV40 T antigen, in situ hybridization successfully demonstrated the messenger RNA for SV40 T antigen.
Conclusions:
The results of this study indicate that latent infection of SV40 in elderly people may be implicated in the tumorigenesis of certain primary GBMs.
Insights
Simian virus 40 (SV40) DNA sequences were found in primary glioblastoma multiforme (GBM) tumors in elderly patients. This suggests a potential role for latent SV40 infection in the development of these brain tumors.
Area of Science:
- Oncology
- Virology
- Molecular Biology
Background:
- Deoxyribonucleic acid (DNA) oncoviruses can cause cancer by interfering with cellular growth control.
- Simian virus 40 (SV40) is a DNA virus linked to various tumors in hamsters and has been detected in human tumors.
- Previous studies reported SV40 DNA in human ependymomas, choroid plexus tumors, and mesotheliomas.
Purpose of the Study:
- To investigate the presence of SV40 DNA sequences in human brain tumors.
- To explore the potential association between SV40 and glioblastoma multiforme (GBM) tumorigenesis.
Main Methods:
- Polymerase chain reaction (PCR) was used to detect SV40 DNA in 32 glioblastoma multiforme (GBM) samples, along with ependymomas and medulloblastomas.
- DNA sequence analysis confirmed the identity of amplified fragments to the SV40 regulatory region.
- Immunohistochemistry and in situ hybridization were employed to detect SV40 T antigen and its messenger RNA (mRNA).
Main Results:
- SV40 DNA sequences were detected in three out of 32 GBM samples.
- No SV40 DNA was found in the examined ependymomas or medulloblastomas.
- The three positive GBMs occurred in elderly patients with wild-type p53 and were classified as primary tumors.
- SV40 T antigen protein was not detected, but SV40 T antigen mRNA was successfully identified in these tumors using in situ hybridization.
Conclusions:
- Latent Simian virus 40 (SV40) infection may play a role in the development of certain primary glioblastoma multiforme (GBM) tumors in elderly individuals.
- Further research is warranted to elucidate the mechanisms of SV40 involvement in GBM tumorigenesis.