Developing Marker for Early Detection of Prostate Cancer

[Guest guest]

http://www.lef.org/news/disease/2001/11/20/a/0000-0030-prostatetest.html

Developing Marker for Early Detection of Prostate Cancer

Scripps Howard News Service

By LEE BOWMAN

November 20, 2001

 

Using a genetic marker to test for prostate cancer could greatly improve

detection at an early stage when the disease

can still be cured, scientists have found.

 

Although the studies on the test are preliminary, researchers at Johns Hopkins

University believe using a genetic marker

would be a dramatic improvement over the current prostate specific antigen (PSA)

test, which can signal prostate cancer

but is also elevated when men have other prostate problems.

 

Prostate cancer is the second-leading cause of cancer death among men in the

United States. More than 198,000 men were

diagnosed with prostate cancer last year, and another 31,500 died from the

disease, although it can usually be

successfully treated if detected early.

 

" A genetic marker that occurs mostly in early-stage cancers may improve the way

we diagnose cancer in the future and

help us catch it early,'' said Dr. David Sidransky, a professor at Hopkins

Medical School and director of the research,

which is published Wednesday in the Journal of the National Cancer Institute.

 

Hopkins has licensed the technique for possible development as a medical test to

a private company, Virco Inc., with

terms of the arrangement being managed by the university in accordance with

conflict-of-interest policies. Sidransky is

a paid consultant for the firm and both he and the university own stock in the

company.

 

Hopkins researchers discovered in 1994 that a mutation in a gene called GSTP1

disrupts chemical processes. Those

processes create a protein that detoxifies environmental carcinogens and

protects against cancer. The mutation, called

hypermethylation, inactivates the GSTP1 gene and is most often seen in

early-stage prostate cancers, but rarely in

normal prostates or benign prostate disease.

 

Armed with this knowledge, the researchers used a methylation-specific genetic

test to examine tissue samples from 69

patients with early-stage prostate cancer and 31 patients with benign prostate

disease. They also evaluated tiny

lesions, thought to be precursors of prostate cancer, found in 28 of the 69

patients with early-stage disease. High

levels of methylation, the genetic marker, were found in 63 of the 69

early-stage patients and in 15 of the 28 lesions.

Some methylation was also found in nine of 31 samples of the patients with

benign disease.

 

The researchers also tested prostate tissue from 21 patients who had high PSA

levels. The genetic test correctly

predicted a diagnosis of prostate cancer in 10 of 11 samples later found to be

positive for cancer using traditional

pathology examination. And they correctly excluded a diagnosis of prostate

cancer in the other 10 patients who turned

out to be negative for cancer.

========================

 

Sounds like a better marker than PSA.

 

========================

Good Health & Long Life,

Greg Watson, gowatson

USDA database (food breakdown) http://www.nal.usda.gov/fnic/foodcomp/

PubMed (research papers) http://www.ncbi.nlm.nih.gov/entrez/query.fcgi

DWIDP (nutrient analysis) http://www.walford.com/dwdemo/dw2b63demo.exe

KIM (omega analysis) http://ods.od.nih.gov/eicosanoids/KIM_Install.exe