Navigation Links
Newly identified stem cells may hold clues to colon cancer
Date:3/29/2012

Vanderbilt-Ingram Cancer Center researchers have identified a new population of intestinal stem cells that may hold clues to the origin of colorectal cancer.

This new stem cell population, reported March 30 in the journal Cell, appears to be relatively quiescent (inactive) in contrast to the recent discovery of intestinal stem cells that multiply rapidly and is marked by a protein, Lrig1, that may act as a "brake" on cell growth and proliferation.

The researchers have also developed a new and clinically relevant mouse model of colorectal cancer that investigators can now use to better understand where and how the disease arises, as well as for probing new therapeutic targets.

Colorectal cancer is the second leading cause of cancer deaths in the United States. These tumors are thought to arise from a series of mutations in intestinal stem cells, which are long-lived, self-renewing cells that gives rise to all cell types in the intestinal tract.

For more than 30 years, scientists believed that intestinal stem cells were primarily quiescent, proliferating only rarely in order to protect the tissue against cancer. Then, in 2007, researchers reported finding a population of intestinal stem cells (marked by the molecule Lgr5) that were highly proliferative.

Those findings "really changed the way we think about intestinal stem cells," said Robert Coffey, Jr., M.D., Ingram Professor of Cancer Research, co-chair of Vanderbilt's Epithelial Biology Center and senior author on the study.

"It came to so dominate the field that it raised the question about whether quiescent stem cells even existand that's where we enter into the picture."

Coffey's lab studies the epidermal growth factor (EGF) signaling pathway which includes a family of receptors known as ErbBs and its role in cancers of epithelial tissues, like the intestinal tract.

Postdoctoral fellow Anne Powell, Ph.D., led the recent experiments showing that Lrig1, a molecule that regulates ErbB activity, is present in intestinal cells that have the qualities of stem cells (self-renewal, and the ability to produce all the cells of the intestine).

"Essentially, what we show is that the Lrig1-expressing cells are stem cells and they are largely quiescent," Powell said. "We also show that they're distinct from the Lgr5-expressing stem cells that had become a sort of 'hallmark' stem cell populationwith different gene expression profiles and different proliferative status."

They also showed that Lrig1 is not only a marker of intestinal stem cells, but also acts as a tumor suppressor and inhibits the growth and proliferative signals of the ErbB family acting as a sort of "brake" on cell proliferation that can lead to cancer.

Postdoctoral fellow Yang Wang, Ph.D., eliminated Lrig1 in mice and showed that nearly all of those mice developed intestinal tumors, providing further evidence suggesting that Lrig1 functions as a tumor suppressor.

The findings underscore the importance of ErbB signaling in the behavior of intestinal stem cells from which colorectal cancer may arise.

Most exciting, said Coffey, is that the mouse model his lab has generated as a part of these studies is one of the only mouse models to develop tumors in section of the intestines where most human tumors develop: the colon. One additional advantage of this model, in contrast to others, is that the tumors develop quickly and can be easily monitored with endoscopy, which will make it easier to assess how therapeutic interventions are working.

"We are fairly confident that this will be the 'go-to' model to study colon cancer in mice for the foreseeable future," Coffey said.


'/>"/>

Contact: Melissa Marino
melissa.marino@vanderbilt.edu
615-322-4747
Vanderbilt University Medical Center
Source:Eurekalert

Related medicine news :

1. Beat The Odds and Get Back on Track; Revitalizing Fitness Training and Exercise Resolutions With Newly Released, Complimentary Video Series
2. Gene discovered for newly recognized disease in Amish children
3. Newly identified proteins critical to FA pathway DNA repair function
4. Khanna Institute to Offer Newly FDA Approved Expanded Range of Intacs for Keratoconus
5. ProbioticSmart.com Re-Launches Newly Expanded Online Store for Human, Pet, and Livestock Health Products and Supplements
6. Newly Relaunched Autoinsurance.net Offers Consumers Smart Tips To Consider When Purchasing Car Insurance
7. Unique and Nutritious Vegetarian Recipes Featured in Newly Released Hand-Bag Friendly “A must have...The Maroema Cook Book”
8. Caregivers Find Hearing Loss Newly Relaunched Website a Welcome Help
9. Altered brain development found in children with newly diagnosed epilepsy
10. Color-coded tracking method helps scientists analyze outcomes of newly transplanted tissue
11. Liberty Health shows how the BP Oil Spill may draw attention to the purity of the company's newly released Nutritional Supplements.
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/25/2016)... ... June 25, 2016 , ... "With 30 hand-drawn hand gesture animations, FCPX users ... - CEO of Pixel Film Studios. , ProHand Cartoon’s package transforms over 1,300 ... Pro X . Simply select a ProHand generator and drag it above media or ...
(Date:6/25/2016)... Montreal, Canada (PRWEB) , ... June 25, 2016 , ... ... the pursuit of success. In terms of the latter, setting the bar too high ... low, risk more than just slow progress toward their goal. , Research from ...
(Date:6/24/2016)... Texas (PRWEB) , ... June 24, 2016 , ... ... International Conference and Scientific Sessions in Dallas that it will receive two significant ... of the grants came as PHA marked its 25th anniversary by recognizing patients, ...
(Date:6/24/2016)... Plano, TX (PRWEB) , ... June 24, 2016 , ... ... taking part in Genome magazine’s Code Talker Award, an essay contest in which patients ... for an award to be presented at the 2016 National Society of Genetic Counselors ...
(Date:6/24/2016)... ... June 24, 2016 , ... National recruitment firm ... sciences executive with extensive sequencing and genomics experience, as Vice President of North American ... Hill will be responsible for leading the sales team in the commercialization of the ...
Breaking Medicine News(10 mins):
(Date:6/26/2016)... -- VMS Rehab Systems, Inc. ( www.vmsrehabsystemsinc.com ) reported today ... to build a strong and stable market for trading ... the OTC Markets-pink current trading platform. Explains ... seeing an anomaly in market trading activities that may ... Company, but shareholders and market players as well. I ...
(Date:6/24/2016)... Mass. , June 24, 2016   ... Spaulding Rehabilitation Network,s Dean Center for Tick ... Physical Medicine and Rehabilitation, MIT Hacking Medicine, University ... for Innovation, today announced the five finalists of ... for Lyme disease.  More than 100 scientists, clinicians, ...
(Date:6/24/2016)... SAN CLEMENTE, Calif. , June 24, 2016 /PRNewswire/ ... pulmonary function testing company, is now able to perform sophisticated lung ... ndd Medical Technologies , Inc. Patients are ... labs.  Thanks to ndd,s EasyOne PRO ® , ARL patients like ... any needed testing done in the comfort of her own home. ...
Breaking Medicine Technology: