Featured Research

from universities, journals, and other organizations

Discovery In Colon Cancer Prevention

Date:
May 20, 2009
Source:
Case Western Reserve University
Summary:
A new study finds that individuals who have low expression of the "Celebrex gene," 15-PGDH, are actually resistant to Celebrex treatment when used to prevent colon cancer.

A new study finds that individuals who have low expression of the "Celebrex gene," 15-PGDH, are actually resistant to Celebrex treatment when used to prevent colon cancer. The study, published in this week's issue of the Proceedings of the National Academy of Sciences (PNAS), is by Sanford Markowitz, M.D., Ph.D., the Markowitz-Ingalls Professor of Cancer Genetics at the Case Western Reserve University School of Medicine and an oncologist at the Ireland Cancer Center of University Hospitals Case Medical Center and his colleagues.

"These findings have two important practical implications," said Markowitz, who is also an investigator in the Howard Hughes Medical Institute. "First, they suggest that measurement of 15-PGDH may identify which individuals are most likely to benefit from treatment with Celecoxib as a colon tumor preventative. Second, they suggest that identifying drugs that could increase 15-PGDH expression in the colon could be a potent new strategy for preventing development of tumors in the colon."

In the Adenoma Prevention with Celecoxib (APC) trial, a clinical trial conducted by Monica Bertagnolli, M.D. at the Harvard Brigham and Women's Hospital and designed to test Celecoxib for the prevention of sporadic colorectal adenomas, the researchers showed that Celecoxib (brand name Celebrex, a Cox-2 inhibitor that relieves pain and inflammation without harming the digestive tract) treatment of individuals who had previously developed colon adenomas cut the rate of developing new adenomas by one-third, and cut the rate of developing new large adenomas by two-thirds. Some individuals however proved resistant to Celecoxib treatment and developed new colon tumors even while on the drug. Colon adenomatous polyps are benign tumors that are the immediate precursors of colon cancers.

Previous studies by Markowitz published in PNAS (December 2004 and July 2006) discovered that the gene 15-PGDH is expressed by the normal colon and acts similarly to Celecoxib in preventing colon tumors by inhibiting the COX-2 pathway.

The current study leads the researchers to ask, 'could protection from colon tumors by Celecoxib actually require the joint action of both the drug and the 15-PGDH gene?'

To answer the question the investigators examined mice that genetically lacked the gene 15-PGDH. In these mice, Celecoxib proved unable to prevent the development of colon tumors, suggesting that both the drug and the gene are needed to protect the colon from tumor development.

The investigators then examined colon biopsies from human patients who had participated in the APC trial of Celecoxib. They found that among these individuals colon 15-PGDH levels varied by 12-fold from lowest to highest. Most importantly, they found that the patients who were resistant to Celecoxib and had developed new colon tumors were all individuals who had low levels of colonic 15-PGDH. Thus in both mice and humans, Celecoxib works to prevent colon tumors only if levels of colonic 15-PGDH are high, while low levels of 15-PGDH leads to Celecoxib resistance.

Markowitz and Bertagnolli point out that these findings should be further confirmed in additional studies with larger numbers of patients. They also agree that it will be important to determine if differences in 15- PGDH levels also account for differences between different individuals in the effectiveness of Celecoxib and similar type drugs, when used for treating pain or inflammation.

Lead authors on the paper are Min Yan, Ph.D., Seung-Jae Myung, M.D., and Stephen Fink, Ph.D., of the department of medicine at the Case Western Reserve University School of Medicine and the Ireland Cancer Center at University Hospitals. Also involved were researchers from the University of Texas M.D. Anderson Cancer Center and the University of Kentucky.

Colon cancer, the second leading cause of cancer deaths in the U.S., accounts for 50,000 deaths annually.


Story Source:

The above story is based on materials provided by Case Western Reserve University. Note: Materials may be edited for content and length.


Cite This Page:

Case Western Reserve University. "Discovery In Colon Cancer Prevention." ScienceDaily. ScienceDaily, 20 May 2009. <www.sciencedaily.com/releases/2009/05/090518173315.htm>.
Case Western Reserve University. (2009, May 20). Discovery In Colon Cancer Prevention. ScienceDaily. Retrieved April 23, 2014 from www.sciencedaily.com/releases/2009/05/090518173315.htm
Case Western Reserve University. "Discovery In Colon Cancer Prevention." ScienceDaily. www.sciencedaily.com/releases/2009/05/090518173315.htm (accessed April 23, 2014).

Share This



More Health & Medicine News

Wednesday, April 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Big Pharma Braces for M&A Wave

Big Pharma Braces for M&A Wave

Reuters - Business Video Online (Apr. 22, 2014) Big pharma on the move as Novartis boss, Joe Jimenez, tells Reuters about plans to transform his company via an asset exchange with GSK, and Astra Zeneca shares surge on speculation that Pfizer is looking for a takeover. Joanna Partridge reports. Video provided by Reuters
Powered by NewsLook.com
Study Says Most Crime Not Linked To Mental Illness

Study Says Most Crime Not Linked To Mental Illness

Newsy (Apr. 22, 2014) A new study finds most crimes committed by people with mental illness are not caused by symptoms of their illness or disorder. Video provided by Newsy
Powered by NewsLook.com
Hagel Gets Preview of New High-Tech Projects

Hagel Gets Preview of New High-Tech Projects

AP (Apr. 22, 2014) Defense Secretary Chuck Hagel is given hands-on demonstrations Tuesday of some of the newest research from DARPA _ the military's Defense Advanced Research Projects Agency program. (April 22) Video provided by AP
Powered by NewsLook.com
How Smaller Plates And Cutlery Could Make You Feel Fuller

How Smaller Plates And Cutlery Could Make You Feel Fuller

Newsy (Apr. 22, 2014) NBC's "Today" conducted an experiment to see if changing the size of plates and utensils affects the amount individuals eat. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins