title: Prevalence of JC polyomavirus genomic sequences from the large T-antigen and non-coding control regions among Bulgarian patients with primary brain tumors.
abstract: A total of 111 fresh brain biopsies from patients with primary brain tumors were examined for JC polyomavirus sequences from the Large T antigen encoding region (LT) and the viral non-coding control region (NCCR). SYBR Green and TaqMan real-time polymerase chain reaction assays were used. In the glioblastoma group of 39 patients 48.7% were positive for LT sequences. Among the astrocytoma group (19 patients) and the oligodendroglioma group (12 patients) 31.6% and 33.3% were also positive. The prevalence of LT genomic sequences among the other groups was as follows: in 2 out of 3 oligoastrocytomas; in 3 out 5 gangliogliomas; in 2 out of 5 meduloblastomas; in 1 out 3 pineocytomas; and in none of the tested 5 ependimomas. All positive samples had a late threshold cycle that varied from 36 to 49, indicative of very low starting viral number. Only 21 of all the 111 samples were positive for NCCR. Low copy number in range of 10-1,000 was present. Notably, only 8 of all NCCR positive specimens were also LT positive. It might be suggested that the disproportion between the results for LT and NCCR is either due to clonally integrated LT fragments, with loss of genetic material, or changes in the NCCR. The latter would alter the productive course of the infection and may establish a premise for continuous interaction of viral regulatory proteins with cell molecules that are responsible for the control of the cell cycle. This may lead subsequently to malignant transformation.
authors: Molecular Virology Laboratory, National Centre of Infectious and Parasitic Diseases, Department of Virology, Sofia, Bulgaria.
authors: Iliya
authors: I
authors: Tsekov
authors: Dilyan
authors: D
authors: Ferdinandov
authors: Ventzeslav
authors: V
authors: Bussarsky
authors: Svetlana
authors: S
authors: Hristova
authors: Zlatko
authors: Z
authors: Kalvatchev
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000952:Antigens, Polyomavirus Transforming / Q000235:genetics*; D001254:Astrocytoma / Q000821:virology; D001483:Base Sequence; D052160:Benzothiazoles; D001932:Brain Neoplasms / Q000821:virology*; D002031:Bulgaria; D002648:Child; D002675:Child, Preschool; D004279:DNA, Viral / Q000032:analysis; D003959:Diamines; D004806:Ependymoma / Q000821:virology; D005260:Female; D018303:Ganglioglioma / Q000821:virology; D005909:Glioblastoma / Q000821:virology; D006801:Humans; D007577:JC Virus / Q000235:genetics*; D008297:Male; D008527:Medulloblastoma / Q000821:virology; D008875:Middle Aged; D008969:Molecular Sequence Data; D009837:Oligodendroglioma / Q000821:virology; D009930:Organic Chemicals; D010871:Pinealoma / Q000821:virology; D016133:Polymerase Chain Reaction; D011804:Quinolines; D022661:RNA, Untranslated / Q000235:genetics*; D017422:Sequence Analysis, DNA
chemical_list: D000952:Antigens, Polyomavirus Transforming; D052160:Benzothiazoles; D004279:DNA, Viral; D003959:Diamines; D009930:Organic Chemicals; D011804:Quinolines; D022661:RNA, Untranslated; C098022:SYBR Green I