Formation of specific complex of SV40 large tumor antigen and p53 in human brain tumors

Abstract

Objective To study the interaction of SV40 early region gene coding product, the large tumor antigen (Tag) with tumor suppressor p53 in human brain tumorigenesis. Methods Tag was detected by immunoprecipitation and Western blot in 43 cases of human brain tumors and 5 cases of normal human brain tissues. Tag-p53 specific complex was screened in 18 Tag positive cases. Results Tag was found in all of 5 ependymomas and 2 choroid plexus papillomas, as well as in pituitary adenomas (5/6), astrocytomas (7/10 ), meningiomas (4/6 ), glioblastomas multiforme ( 3/5 ) and medulloblastomas ( 2/5 ). None of the 5 normal brain tissues were positive for Tag, nor were 3 oligodendrogliomas and 1 pineocytoma. Tag-p53 complexs were found in all of 18 Tag positive cases. Conclusion SV40 Tag can form a specific complex with p53 in human brain tumors, the inactivation of p53 due to the formation of Tag-p53 complex may be one of the important mechanisms of human brain tumorigenesis.