Featured Research

from universities, journals, and other organizations

Colon Cancer A Disease Of Hormone Deficiency, Scientists Suggest

Date:
August 3, 2007
Source:
Thomas Jefferson University
Summary:
Researchers have found new evidence suggesting that colon cancer is a disease of missing hormones that could potentially be treated by hormone replacement therapy. Early in colon cancer development, two intestinal cell growth-controlling hormones are "lost," disrupting the activity of the hormones' receptor, GCC. Using two mouse models of colon cancer development in people, the scientists showed that GCC signaling blocks tumors from forming, meaning that colon cancer could be a disease of hormone insufficiency.

Researchers at the Kimmel Cancer Center at Jefferson in Philadelphia have found new evidence suggesting that colon cancer is actually a disease of missing hormones that could potentially be treated by hormone replacement therapy.

Reporting August 1, 2007 in the journal Gastroenterology, clinical pharmacologist Scott Waldman, M.D., Ph.D., professor and chair of pharmacology and experimental therapeutics at Jefferson Medical College of Thomas Jefferson University, and his co-workers showed that GCC -- guanylyl cyclase C, a protein receptor on the surface of intestinal epithelial cells for two hormones, guanylin and uroguanylin, can suppress tumor formation. These hormones regulate the growth of intestinal epithelial cells.

But early in colon cancer development, these growth-controlling hormones are "lost" and not expressed, disrupting GCC's activity, and, Dr. Waldman believes, contributing to tumor formation. Using two separate mouse models that mimic the development of colon cancer in people, his team showed that GCC signaling blocks such tumors from forming.

According to Dr. Waldman, the group found that GCC stops tumors from forming through two different mechanisms. In one case, it controls cell growth, while in the other, it maintains "regulation of genomic integrity."

In one mouse cancer model, the animals carried mutations in the APC gene, which causes colon polyps that frequently lead to colon cancer. Mice in the other cancer-development model were exposed to a commonly used experimental cancer-causing agent, azoxymethane. "We modeled both ways that humans develop colon cancer, and studied the effects of a lack of GCC on the incidence of colon cancer development," he explains.

"We found that in animals that have APC mutations, tumors developed in the colon and small intestine, which is expected," Dr. Waldman says. "A lack of GCC resulted in both larger tumors and a greater number of tumors in the large intestine." In the carcinogen model, the absence of GCC caused an increase in both tumor number and size also.

The findings indicate that the mechanism of the increase in tumor development through loss of GCC expression was a combination, in both models, of a loss of genomic integrity and an increase in cell growth. "When you eliminate GCC from cells, they develop a level of genomic instability, where they start accumulating more mutations and lose pieces of genetic material," he explains.

"Putting those pieces together -- exposure to carcinogen or spontaneous mutations in APC -- which happens to almost every colorectal cancer patient, and the loss of GCC signaling brought on by a loss of the two hormones in one of the earliest events that occurs in tumor development in the intestine," he notes, "and it's a recipe for colon cancer."

The finding "converts colon cancer from a genetic disease, which is the way we've all thought about it, to a disease of hormone insufficiency," Dr. Waldman says. "It's a completely different way of thinking about the disease.

"Not only does this give a new paradigm in how we think about the disease, but it gives us a new paradigm for treating the disease -- that is, by hormone replacement therapy.

Essentially, this takes the genetic disease and converts it to an endocrine disease, with a hormone solution." The researchers would like to extend these studies to show that by treating patients with hormone replacement therapy, intestinal cancer formation can either be prevented or treated.


Story Source:

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


Cite This Page:

Thomas Jefferson University. "Colon Cancer A Disease Of Hormone Deficiency, Scientists Suggest." ScienceDaily. ScienceDaily, 3 August 2007. <www.sciencedaily.com/releases/2007/08/070801091319.htm>.
Thomas Jefferson University. (2007, August 3). Colon Cancer A Disease Of Hormone Deficiency, Scientists Suggest. ScienceDaily. Retrieved September 2, 2014 from www.sciencedaily.com/releases/2007/08/070801091319.htm
Thomas Jefferson University. "Colon Cancer A Disease Of Hormone Deficiency, Scientists Suggest." ScienceDaily. www.sciencedaily.com/releases/2007/08/070801091319.htm (accessed September 2, 2014).

Share This




More Health & Medicine News

Tuesday, September 2, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Get on Your Bike! London Cycling Popularity Soars Despite Danger

Get on Your Bike! London Cycling Popularity Soars Despite Danger

AFP (Sep. 1, 2014) Wedged between buses, lorries and cars, cycling in London isn't for the faint hearted. Nevertheless the number of people choosing to bike in the British capital has doubled over the past 15 years. Duration: 02:27 Video provided by AFP
Powered by NewsLook.com
Can You Train Your Brain To Eat Healthy?

Can You Train Your Brain To Eat Healthy?

Newsy (Sep. 1, 2014) New research says if you condition yourself to eat healthy foods, eventually you'll crave them instead of junk food. Video provided by Newsy
Powered by NewsLook.com
We've Got Mites Living In Our Faces And So Do You

We've Got Mites Living In Our Faces And So Do You

Newsy (Aug. 30, 2014) A new study suggests 100 percent of adult humans (those over 18 years of age) have Demodex mites living in their faces. Video provided by Newsy
Powered by NewsLook.com
Liberia Continues Fight Against Ebola

Liberia Continues Fight Against Ebola

AFP (Aug. 30, 2014) Authorities in Liberia try to stem the spread of the Ebola epidemic by raising awareness and setting up sanitation units for people to wash their hands. Duration: 00:41 Video provided by AFP
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