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:10/13/2017)... ... October 13, 2017 , ... Ellevate Network, the leading network for professional women, ... towards gender equality at their inaugural Summit in New York City in June. The ... social audience of over 3 million. To watch the Mobilize Women video, click ...
(Date:10/13/2017)... ... October 13, 2017 , ... ... Software Development, has been awarded a contract by the Center for Medicare and ... aims to accelerate the enterprise use of Agile methodologies in a consistent and ...
(Date:10/12/2017)... San Francisco, CA (PRWEB) , ... October 12, ... ... and Dr. Cheng, are now treating sleep apnea using cutting-edge Oventus ... sleep apnea, a serious sleep disorder characterized by frequent cessation in breathing. Oral ...
(Date:10/12/2017)... Bethesda, MD (PRWEB) , ... October 12, 2017 , ... ... Award of Excellence to Carol Friedman, PhD, FACMI, during the Opening Session of AMIA’s ... 4 – 8. , In honor of Morris F. Collen, a pioneer in the ...
(Date:10/12/2017)... ... October 12, 2017 , ... HMP , a leader in ... 2017 Folio Magazine Eddie Digital Award for ‘Best B-to-B Healthcare Website.’ Winners were announced ... 2017. , The annual award competition recognizes editorial and design excellence across a range ...
Breaking Medicine News(10 mins):
(Date:10/12/2017)... --  Divoti USA will engrave and process all ... the latest FDA requirements, which stipulates new criteria regarding medical device ... of Medical ID jewelry such as Medical ID Bracelets, can rest ... terms of the new FDA requirements . ... Divoti offers this dark mark fiber laser engraving ...
(Date:10/11/2017)... , Oct. 11, 2017  BioPharmX Corporation (NYSE ... team that developed an innovative way to use nonlinear ... the delivery of new drugs. ... Clinical Dermatology Conference will show how researchers from BioPharmX ... Harvard Medical School used a suite of imaging techniques ...
(Date:10/11/2017)...  True Health, a leader in integrated diagnostics ... National Breast Cancer Awareness month to educate doctors ... Research recently published in ... than 10 million American women are at significant ... BRCA2 and have not had testing. These mutations can ...
Breaking Medicine Technology: