Navigation Links
Protein thought to promote cancer instead functions as a tumor suppressor
Date:7/7/2008

DALLAS July 7, 2008 A protein previously thought to promote colorectal cancer instead suppresses the growth of human cancer cells in culture, researchers at UT Southwestern Medical Center have found.

"This finding reshapes a fundamental model of how colorectal cancer arises," said Dr. Lawrence Lum, assistant professor of cell biology at UT Southwestern and senior author of the study, which appears online today and in a future issue of the Proceedings of the National Academy of Sciences.

Approximately 90 percent of colorectal cancers are caused by a biochemical malfunction that arises from mutations in a gene that activates a gene called TCF7L2, Dr. Lum said. As a result, TCF7L2 has been suspected of helping to trigger colorectal cancer.

In the current study, the researchers used a novel genetic screening approach known as RNAi mediated interference, or RNAi, to identify genes that contributed to this malfunction.

The researchers employed more than 80,000 small snippets of chemically synthesized RNAs (ribonucleic acids) known as "small interfering RNAs" or siRNAs, that are each capable of inactivating a specific gene. The researchers mixed these siRNAs with specially engineered human cancer cells that glowed when the cancer-causing malfunction is activated. When an siRNA made a cell glow, the researchers were able to flag the gene as a candidate cancer gene.

As the researchers examined the genes of interest more closely, they unexpectedly found that a gene called TCF7L2, which had been thought to boost malignant cell growth, instead suppressed it. When the gene was inactivated, human colorectal cancer cells grew more rapidly in culture and emitted a stronger glow.

"The function of TCF7L2 in cancer was previously determined from studies in animals but no one has genetically tested its role in human colorectal cancer cells before," said Dr. Lum, who is a Virginia Murchison Linthicum Scholar in Medical Research. "Prior to the advent of RNAi technology, this was very difficult to do in human cultured cells."

The next step is to understand more fully all the steps in the biochemical pathway involved in controlling the action of TCF7L2. This knowledge could then be used to identify new therapeutic targets for treating colorectal cancer. Therapeutic strategies derived from such studies may also be useful in treating type II diabetes, for which risk is strongly associated with mutations in TCF7L2, Dr. Lum said.

Dr. Lum noted that the findings about TCF7L2 show the effectiveness of this high throughput screening technique, which can quickly and systematically check many thousands of genes.

The success of this relatively new screening method for identifying candidate cancer genes demonstrates its usefulness to understanding human disease, Dr. Lum said.

"It's a way to analyze human gene action directly in human tissue at a genome-scale," he said.


'/>"/>

Contact: Aline McKenzie
aline.mckenzie@utsouthwestern.edu
214-648-3404
UT Southwestern Medical Center
Source:Eurekalert  

Related medicine news :

1. Draining away brains toxic protein to stop Alzheimers
2. Penn study finds pro-death proteins required to regulate healthy immune function
3. New prion protein discovered by Canadian scientists may offer insight into mad cow disease
4. Emory researchers identify signaling protein for multiple myeloma
5. Human C-reactive protein regulates myeloma tumor cell growth and survival
6. Lowering Blood Protein Wont Help Kidney Patients
7. Blood protein detects lung cancer, even at earliest stage
8. Natural Protein Could Help Spot, Treat Liver Cancer
9. Heat shock proteins are co-opted for cancer
10. How adhesive protein causes malaria
11. Loss of gene leads to protein splicing and buildup of toxic proteins in neurons
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Protein thought to promote cancer instead functions as a tumor suppressor
(Date:2/12/2016)... ... 12, 2016 , ... Young Asset Protection, a full service ... the latest charity campaign in their community enrichment program. Art Expression utilizes after-school ... cause are currently being accepted at: http://artexpressioninc.org/ . , Art Expression is ...
(Date:2/12/2016)... ... February 12, 2016 , ... J Thomas ... by continuing it’s commitment to act as Agents of Change in the community, ... with area homeless families to fulfill immediate needs and help them move into ...
(Date:2/12/2016)... Pa. (PRWEB) , ... February 12, 2016 , ... ... sort through a world of exterior design possibilities. CertainTeed, North America’s leading brand ... tools by expanding the product offerings showcased in the mobile version of the ...
(Date:2/12/2016)... ... February 12, 2016 , ... The Central Coast Autism Spectrum Center (CCASC) invites teens ages 11-18 ... night of fun for teens with and without special needs to gather in a safe ... the event. The dance will take place on Saturday, Feb. 13 from 7 to 9:30 ...
(Date:2/12/2016)... CA (PRWEB) , ... February 12, 2016 , ... ... Film Studios. The new cartoon style themes are great for showcasing pictures, videos as ... customized scene generators, titles like introductions, lower thirds, transitions and a beautiful frame overlay. ...
Breaking Medicine News(10 mins):
(Date:2/12/2016)... 12, 2016  Innophos Holdings, Inc. (NASDAQ: IPHS ), ... today announced that it will host a live conference call ... discuss its fourth quarter and full year 2015 results. ... release detailing fourth quarter and full year results will be ... --> --> The conference ...
(Date:2/12/2016)... -- SI-BONE, Inc., a medical device company that pioneered the use of ... (MIS) device indicated for fusion for certain disorders of the sacroiliac ... Administrative Contractor (MAC) covering the states of Connecticut ... Massachusetts , Minnesota , ... Rhode Island , Vermont ...
(Date:2/12/2016)... 2016 On Thursday, Feb. 11, 2016, surgeons ... David,s North Austin Medical Center successfully completed the first ... ® Surgical System with Trumpf Medical,s advanced operating ... Lakshman , M.D., colorectal surgeon at the Texas Institute ... Table Motion technology, which seamlessly combines the da Vinci ...
Breaking Medicine Technology: