Navigation Links
Researchers identify breast cancer culprits
Date:8/17/2010

Scientists have discovered an accomplice in breast cancer a master control switch with the power to set off a cascade of reactions orchestrated by a cancer-causing gene (or oncogene) named Wnt1. This executive molecule and its modus operandi are reported in back-to-back papers featured on the cover of the August 15 issue of Cancer Research.

"These papers are about the regulation of a Wnt oncogene," explains lead author Rakesh Kumar, Ph.D., professor and the Catharine Birch & William McCormick Chair of the department of biochemistry and molecular biology at The George Washington University School of Medicine and Health Sciences. Now, Kumar and his team describe how a master switch sparks a type of Wnt signaling in breast cancer. Moreover, this master control switch may help explain why increased levels of a protein called MTA1 (metastasis-associated protein 1) are oncogenic in certain types of breast cancer.

Like many molecular pathways underlying cancer, Wnt pathways govern normal processes like embryonic development and the communication between cells in healthy people. For reasons little understood, however, certain types of Wnt proteins sometimes go awry, sending off cascades of signals that turn normal cells into cancerous ones. Researchers often find evidence of Wnt pathway activation when they analyze what genes are turned on in tumors. Although Wnt has been connected with breast cancer for nearly 30 years, however, the signals (other than mutations) that trigger it remain largely unknown.

Kumar and his team have implicated MTA1 and a shorter variation of the protein, MTA1s, in Wnt1 (a type of Wnt) pathway activation. MTA1 belongs to the MTA family of genes, which help a range of cancers progress in a variety of ways. Before this study, researchers knew that MTA1 levels were higher than normal in breast, ovarian, prostate, colorectal, gastric, liver tumors, and more. But they still didn't know everything about what MTA's were doing there.

In the current studies, funded by a grant from the National Cancer Institute, Kumar's team finds that MTA1 expression triggers cancer-causing signals from Wnt1 in human breast cancer cells. This Wnt1 signaling cascade leads to tumors, they demonstrate, by showing that 8.8 percent of mice bearing artificially elevated levels of MTA1s grew tumors in their mammary glands.

To get down to the details, Kumar and his fellow researchers show that MTA1 and MTA1s activate the cancer-causing pathway by reducing the levels of a protein known as Six3. This protein is known to inhibit Wnt1 in brain cells, but in their study involving breast cancer cells, it inhibited Wnt1 in a rather non-intuitive way. Six3 normally puts the brakes on Wnt signaling, and so when MTA1 obstructed Six3, Wnt1 signals let loose. In addition, the team found that MTA1s also promoted Wnt signaling directly and through another known Wnt-related pathway namely ERK-mediated GSK3.

Because inflammation may drive MTA1, and since inflammation is believed to drive certain forms of cancer, Kumar's work suggests one possible reason for why worsening cancer progression has been correlated with other inflammation-inducers. "We've raised the next level question," says Kumar, "and now we're going back into the lab to ask if this pathway plays a role in inflammation-related cancer."


'/>"/>

Contact: Anne Banner
mcmacb@gwumc.edu
202-994-2261
George Washington University Medical Center
Source:Eurekalert

Related medicine news :

1. Gulf Oil Spill Still a Health Threat to Many, Researchers Report
2. Researchers identify potential new target for ovarian cancer
3. Amphetamine use increases risk of aortic tears in young adults, UT Southwestern researchers report
4. Researchers find function of proteins that can enhance the progression of viruses and cancer cells
5. In NIH-funded study, researchers uncover step in brain events leading up to addiction
6. Researchers develop magnetic molecular machines to deliver drugs to unhealthy cells
7. UCLA researchers discover protein that shuttles RNA into cell mitochondria
8. Help wanted: Highly cited researchers needed for high-ranking positions at research institutions
9. NIST researchers measure high infrared power levels from some green lasers
10. Mayo Clinic researchers share latest findings in CT radiation dose reduction efforts
11. Researchers develop advanced search tool to help physicians sort and retrieve vital EMR data
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/25/2016)... ... 2016 , ... As a lifelong Southern Californian, Dr. Omkar Marathe earned his ... David Geffen School of Medicine at UCLA. He trained in Internal Medicine at Scripps ... in hematology/oncology at the UCLA-Olive View-Cedars Sinai program where he had the opportunity to ...
(Date:6/24/2016)... Los Angeles, CA (PRWEB) , ... June 24, 2016 , ... ... plastic surgery procedures that most people are unfamiliar with. The article goes on to ... known procedures, but also many of these less common operations such as calf and ...
(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)... ... June 24, 2016 , ... Topical BioMedics, Inc, makers of Topricin and MyPainAway Pain ... for a minimum wage raise to $12 an hour by 2020 and then adjusting it ... the lost value of the minimum wage, assure the wage floor does not erode again, ...
(Date:6/24/2016)... (PRWEB) , ... June 24, 2016 , ... ... client, The Grove Investment Group (TGIG), has initiated cultivation and processing operations at ... Las Vegas and Pahrump, Nevada. , Puradigm is the manufacturer of a complete ...
Breaking Medicine News(10 mins):
(Date:6/24/2016)... , June 24, 2016 ... appointment of Dr. Edward Futcher to ... Director, effective June 23, 2016.Dr. Futcher was also ... and Governance Committees.  As a non-executive member of ... expertise and strategic counsel to VolitionRx in connection ...
(Date:6/23/2016)... 23, 2016  MedSource announced today that it ... software solution of choice.  This latest decision demonstrates ... to their clients by offering a state-of-the-art electronic ... establishes nowEDC as the EDC platform of choice ... clients.  "nowEDC has long been a preferred EDC ...
(Date:6/23/2016)... , June 23, 2016 Any dentist who has ... of the current process. Many of them do not even ... technical difficulties and high laboratory costs involved. And those who ... it at such a high cost that the majority of ... Dr. Parsa Zadeh , founder of Dental Evolutions ...
Breaking Medicine Technology: