Detection of JC virus DNA sequences in colorectal cancers in Japan.
JC virus (JCV), a ubiquitous polyoma virus that commonly infects humans, was first identified as the etiologic agent for the fetal demyelinating disease, progressive multifocal leukoencephalopathy. Recently, a number of reports have documented detection of JCV in samples derived from several types of neural as well as non-neural human tumors. It has been suggested that oncogenicity of JCV depends on a T antigen having a strict structural homology to the T antigen of simian virus 40. To clarify whether JCV might have a potential role with regard to colorectal cancers, we investigated the presence of its genome in a series of cases along with colorectal adenomas and normal colonic mucosa, targeting T antigen, VP and agnoprotein by nested polymerase chain reaction and Southern blotting and T antigen by immunohistochemistry. While VP and agnoprotein were not found in any of the samples examined, T antigen was detected in 6 of 23 colorectal cancers (26.1%) and 1 of 21 adenomas (4.8%), but none of 20 samples of normal colonic mucosa. No clear and diffuse staining with anti-T-antigen antibodies (1:100) could be detected, and there was no correlation with CD20-positive cells, which might have indicated JCV latent infection of B lymphocytes. Presence of T antigen did not influence clinicopathological variables, including survival. In one colonic cancer case positive for T antigen together with lymph node metastasis, DNA extracted from cancer cells in the lymph node revealed no detection of T antigen. Our results are in the intermediate position between the high T antigen rate (81%) in one report and the lack of it (0%) in another focused on colon cancers. It was concluded that T antigen might be integrated in cancer cells in approximately one fourth of Japanese colon cancer cases without clear and diffuse expression of the protein, suggesting a possible role in oncogenesis which might involve a hit-and-run mechanism.
Hori
Ryouta
R
First Department of Pathology, Faculty of Medicine, Toyama Medical and Pharmaceutical University, 2630 Sugitani, Toyama, 930-0152, Japan, ytakano@ms.toyama-mpu.ac.jp.
Murai
Yoshihiro
Y
Tsuneyama
Kouichi
K
Abdel-Aziz
Hekmat Osman
HO
Nomoto
Kazuhiro
K
Takahashi
Hiroyuki
H
Cheng
Chun-mei
CM
Kuchina
Tomohiko
T
Harman
Brian V
BV
Takano
Yasuo
Y
D000230:Adenocarcinoma / Q000473:pathology / Q000821:virology*; D000236:Adenoma / Q000473:pathology / Q000821:virology*; D000293:Adolescent; D000368:Aged; D000369:Aged, 80 and over; D018951:Antigens, CD20 / Q000378:metabolism; D000957:Antigens, Viral, Tumor / Q000032:analysis; D015139:Blotting, Southern; D015179:Colorectal Neoplasms / Q000473:pathology / Q000821:virology*; D004279:DNA, Viral / Q000032:analysis*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007577:JC Virus / Q000235:genetics* / Q000276:immunology; D007564:Japan; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D011379:Prognosis; D014412:Tumor Virus Infections / Q000453:epidemiology*; D014764:Viral Proteins / Q000032:analysis; D054334:Viral Regulatory and Accessory Proteins; D000086082:Viroporin Proteins
D018951:Antigens, CD20; D000957:Antigens, Viral, Tumor; D004279:DNA, Viral; D014764:Viral Proteins; D054334:Viral Regulatory and Accessory Proteins; C042559:agnoprotein, polyomavirus; D000086082:Viroporin Proteins