Navigation Links
Potential new 'twist' in breast cancer detection
Date:12/4/2009

Working with mice, scientists at Johns Hopkins publishing in the December issue of Neoplasia have shown that a protein made by a gene called "Twist" may be the proverbial red flag that can accurately distinguish stem cells that drive aggressive, metastatic breast cancer from other breast cancer cells.

Building on recent work suggesting that it is a relatively rare subgroup of stem cells in breast tumors that drives breast cancer, scientists have surmised that this subgroup of cells must have some very distinctive qualities and characteristics.

In experiments designed to identify those special qualities, the Hopkins team focused on the gene "Twist" (or TWIST1) named for its winding shape because of its known role as the producer of a so-called transcription factor, or protein that switches on or off other genes. Twist is an oncogene, one of many genes we are born with that have the potential to turn normal cells into malignant ones.

"Our experiments show that Twist is a driving force among a lot of other players in causing some forms of breast cancer," says Venu Raman, Ph.D., associate professor of radiology and oncology, Johns Hopkins University School of Medicine. "The protein it makes is one of a growing collection of markers that, when present, flag a tumor cell as a breast cancer stem cell."

Previous stem cell research identified a Twist-promoted process known as epithelial-to-mesenchymal transition, or EMT, as an important marker denoting the special subgroup of breast cancer stem cells. EMT essentially gets cells to detach from a primary tumor and metastasize. The new Hopkins research shows that the presence of Twist, along with changes in two other biomarkers CD 24 and CD44 even without EMT, announces the presence of this critical sub-group of stem cells.

"The conventional thinking is that the EMT is crucial for recognizing the breast cancer cell as stem cells, and the potential for metastasis, but our studies show that when Twist shows up in excess or even at all, it can work independently of EMT," says Farhad Vesuna, Ph.D., an instructor of radiology in the Johns Hopkins University School of Medicine. "EMT is not mandatory for identifying a breast cancer stem cell."

Working with human breast cancer cells transplanted into mice, all of which had the oncogene Twist, the scientists tagged cell surface markers CD24 and CD44 with fluorescent chemicals. Following isolation of the subpopulation containing high CD44 and low CD24 by flow cytometry, they counted 20 of these putative breast cancer stem cells. They then injected these cells into the breast tissue of 12 mice. All developed cancerous tumors.

"Normally, it takes approximately a million cells to grow a xenograft, or transplanted tumor," Vesuna says. "And here we're talking just 20 cells. There is something about these cells something different compared to the whole bulk of the tumor cell that makes them potent. That's the acid test if you can take a very small number of purified "stem cells" and grow a cancerous tumor, this means you have a pure population."

Previously, the team showed that 65 percent of aggressive breast cancers have more Twist compared to lower-grade breast cancers, and that Twist-expressing cells are more resistant to radiation.

Twist is what scientists refer to as an oncogene, one that if expressed when and where it's not supposed to be expressed, causes oncogenesis or cancer because the molecules and pathways that once regulated it and kept it in check are gone.

This finding that Twist is integral to the breast cancer stem cell phenotype has fundamental implications for early detection, treatment and prevention, Raman says. Some cancer treatments may kill ordinary tumor cells while sparing the rare cancer stem cell population, sabotaging treatment efforts. More effective cancer therapies likely require drugs that kill this important stem cell population.


'/>"/>

Contact: Maryalice Yakutchik
myakutc1@jhmi.edu
443-287-2251
Johns Hopkins Medical Institutions
Source:Eurekalert

Related medicine news :

1. Rcadia COR Analyzer(R) System Demonstrates Potential in Emergency Department Triage of Chest Pain Patients at Low to Moderate Risk of Coronary Artery Disease
2. Researchers identify proteins in lung cancer cells that may provide potential drug targets
3. Candidate Potential Report Reduces Risk of Bad Hires
4. Pivotal study for PSD502 -- the first potential treatment for premature ejaculation
5. Heavy Snoring Linked To Potentially Life-Threatening Conditions
6. U.S. Healthcare Efficiency Index(TM) Launches Primary Data Collection to Measure Current State of Electronic Adoption and Potential Cost Savings
7. New activity found for a potential anti-cancer agent
8. Surgery potentially best option for severe migraine headaches
9. Canadian scientists link fat hormone to death from potentially deadly blood infection
10. CEL-SCI Presents Data at American College of Rheumatology Conference Which Suggests that CEL-2000 Has Potential to Slow Damage Caused by Rheumatoid Arthritis
11. Mice regain ability to extend telomeres suggesting potential for dyskeratosis congenita therapy
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/27/2016)... ... ... TherapySites, the leading website and online marketing ... Association. This new relationship allows TherapySites to continue to extend their online ... and promotional offers. , "TCA is extremely excited about this new partnership, as ...
(Date:6/27/2016)... ... June 27, 2016 , ... TopConsumerReviews.com recently awarded their highest five-star rating to ... of individuals in the United States and Canada wear eyeglasses. Once considered to be ... vision and make a fashion statement. Even celebrities use glasses as a way of ...
(Date:6/26/2016)... ... ... Pixel Film Studios Released ProSlice Levels, a Media Slicing Effect Plugin ... whole new perspective by using the title layers in ProSlice Levels to split-up ... Levels contains over 30 Different presets to choose from. FCPX users can ...
(Date:6/26/2016)... ... June 26, 2016 , ... Many women are ... with endometriosis. These women need a treatment plan to not only alleviate symptoms ... can help for preservation of fertility and ultimately achieving a pregnancy. The specialists ...
(Date:6/25/2016)... ... ... temporary closing of Bruton Memorial Library on June 21 due to a possible lice infestation, ... aspect of head lice: the parasite’s ability to live away from a human host, and ... necessary one in the event that lice have simply gotten out of control. , As ...
Breaking Medicine News(10 mins):
(Date:6/23/2016)... , June 23, 2016 Roche (SIX: ... 510(k) clearance for its Elecsys BRAHMS PCT (procalcitonin) assay ... sepsis or septic shock. With this clearance, Roche is ... a fully integrated solution for sepsis risk assessment and ... with bacterial infection and PCT levels in blood can ...
(Date:6/23/2016)... , June 23, 2016 Bracket , ... launch its next generation clinical outcomes platform, Bracket eCOA (SM) ... held on June 26 – 30, 2016 in ... first electronic Clinical Outcome Assessment product of its kind to ... #715. Bracket eCOA 6.0 is a flexible platform ...
(Date:6/23/2016)... LONDON , June 23, 2016 ... environments  Oticon , industry leaders in ... the launch of Oticon Opn ™, the world,s ... world of possibilities for IoT devices.      ... Opn, Oticon introduces a number of ,world firsts,: ...
Breaking Medicine Technology: