Previous Article | Next Article ![]()
Journal of Virology, February 2001, p. 1996-2001, Vol. 75, No. 4
Department of Medicine and Cancer Center,
University of California, San Diego, La Jolla, California
92093-0688
Received 28 August 2000/Accepted 6 November 2000
JC virus (JCV), along with other members of the polyomavirus
family, encodes a class of highly conserved proteins, T antigens, that
are capable of inducing aneuploidy in cultured cells. We have
previously isolated T-antigen DNA variants of JCV from both colon
cancer tissues and the corresponding nonneoplastic gastrointestinal tissues, raising new questions about the role of JCV in the development of chromosomal instability of the colon. Based on the sequence of the
transcriptional control region (TCR), JCV can be classified as
archetype or tandem repeat variants. Among the latter, Mad-1, the
prototype virus first isolated from a patient with progressive multifocal leukoencephalopathy, is characterized by lacking the 23- and
66-bp sequences that are present in the archetype and by duplication of
a 98-bp sequence. In this study, we evaluated differences in the TCR of
JCV isolated from colon cancer tissues and nonneoplastic epithelium. To
characterize JCV variants, we first treated eight pairs of DNA samples
from colon cancers and noncancerous tissue with topoisomerase I and
then amplified and cloned the JCV TCR. We obtained 285 recombinant
clones from the JCV TCR, 157 from nonneoplastic samples, and 128 from
colon cancer tissues. Of these clones, 262 spanned the length of the
JCV Mad-1 TCR: 99.3% from nonneoplastic samples and 82.8% from colon
cancer tissues. In sequencing 54 clones in both directions, we did not find archetype JCV either in the nonneoplastic tissue or in the cancer
samples. From all colon cancer tissues, 18 clones had a deletion of one
98-bp tandem repeat. This deleted strain was not detected in any of the
nonneoplastic tissues (14 versus 0% [
0022-538X/01/$04.00+0 DOI: 10.1128/JVI.75.4.1996-2001.2001
Copyright © 2001, American Society for Microbiology. All rights reserved.
Mad-1 Is the Exclusive JC Virus Strain Present in the Human
Colon, and Its Transcriptional Control Region Has a Deleted
98-Base-Pair Sequence in Colon Cancer Tissues
2 = 23.6;
P < 0.001]). Our study demonstrates that the only
JCV strain present in the human colon is Mad-1, and the variant with a
single 98-bp sequence is found exclusively in the cancer tissues. This
strain may be involved in the development of chromosomal instability.
*
Corresponding author. Mailing address: Department of
Medicine and Cancer, University of California, San Diego, 4028 Basic Science Building, 9500 Gilman Dr., La Jolla, CA 92093-0688. Phone: (858) 822-0300. Fax: (858) 822-0301. E-mail:
crboland{at}ucsd.edu.
This article has been cited by other articles:
| J. Bacteriol. | Mol. Cell. Biol. | Microbiol. Mol. Biol. Rev. |
|---|
| Clin. Vaccine Immunol. | ALL ASM JOURNALS |
|---|