Navigation Links
Tumor suppressor genes vital to regulating blood precursor cells in fruit flies
Date:9/5/2012

UCLA stem cell scientists have shown that two common tumor suppressor genes, TSC and PTEN, are vital to regulating the stem cell-like precursor cells that create the blood supply in Drosophila, the common fruit fly.

The researchers examined a signaling pathway called TOR that the cells use to gauge nutrition levels and stress, said study senior author Dr. Julian A. Martinez-Agosto, an assistant professor of human genetics and pediatrics and a researcher with the Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research at UCLA.

"We wondered how an organism knows how many blood cells to make and when to make them in the context of injury and repair to tissue. In particular, we wondered how the blood progenitor cells sense that change and know when it's time to make more blood cells," Martinez-Agosto said. "We found that the TOR pathway uses these two genes to regulate its function and, when activated, it expands or increases the number of blood progenitor cells in the fly's blood."

The study appears Sept. 5, 2012 in the advance online issue of the peer-reviewed journal Development.

Michelle Dragojlovic-Munther, a graduate student in the Martinez-Agosto laboratory and first author of the study, found that cells with increased activity of TOR have a competitive advantage, allowing them to divide and make more of themselves so they can make blood. These progenitors, Dragojlovic-Munther found, also have high levels of reactive oxygen species (ROS) - ions or very small molecules that include free radicals which are known to damage cells and can predispose humans to aging and heart disease. But in this case, the ROS proved valuable.

The precursors, Martinez-Agosto said, were producing ROS all the time and when TOR was activated, the levels increased dramatically. Too much ROS caused them to divide more than normal. If they treated the flies with antioxidants, which reduce ROS levels, the cells would develop normally.

The finding could be important because the TOR pathway is abnormally activated in many cancers, and it may be possible to target the levels of ROS, which may help regulate the pathway.

"What this study may be telling us is that too much ROS is causing more cells to divide and we may be able to target therapies that reduce ROS to significantly improve the condition," Martinez-Agosto said, adding that specifically targeted antioxidants might be a potential treatment in certain subsets of blood disorders. "Sometimes that pathway is working more than it should, and we need the right amount of ROS for balance. It's like Goldilocks, there can't be too little or too much. We need it just right."

Going forward, Martinez-Agosto and his team will try to determine where the ROS is coming from and perhaps discover an enzyme that may be a good target for therapeutics. They know that the higher ROS levels in blood progenitors are not coming from mitochondria, the cell's power source, but have not identified how they are being produced.

"This study highlights mechanistic differences between TSC and PTEN on TOR function and demonstrates the multifaceted roles of a nutrient-sensing pathway in orchestrating proliferation and differentiation of myeloid-specific blood progenitors through regulation of ROS levels and the resulting myeloproliferative disorder when deregulated," the study states.


'/>"/>
Contact: Kim Irwin
kirwin@mednet.ucla.edu
310-425-9457
University of California - Los Angeles Health Sciences
Source:Eurekalert

Related medicine news :

1. Improved Stem Cell Line May Avoid Tumor Risk: Study
2. Normalizing tumor blood vessels improves delivery of only the smallest nanomedicines
3. Dental X-Rays May Be Linked to Benign Brain Tumors
4. Live imaging shows response to cancer drugs can be boosted by altering tumor microenvironment
5. Brain Tumor Vaccine Shows Promise in Early Trial
6. Kidney Cancer Patients Fare Better With Tumor Removal Only
7. IBN discovers human neural stem cells with tumor targeting ability
8. Protein prevents DNA damage in the developing brain and might serve as a tumor suppressor
9. Small molecular bodyguards kill HPV-infected cancer cells by protecting tumor-suppressor
10. New surgical technique for removing inoperable tumors of the abdomen
11. Combination of 2 drugs reverses liver tumors
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/25/2016)... ... , ... "With 30 hand-drawn hand gesture animations, FCPX users can easily customize ... Pixel Film Studios. , ProHand Cartoon’s package transforms over 1,300 hand-drawn pictures into ... Simply select a ProHand generator and drag it above media or text in the ...
(Date:6/25/2016)... Oklahoma City, Oklahoma (PRWEB) , ... June 25, ... ... to helping both athletes and non-athletes recover from injury. Recently, he has implemented ... for the Oklahoma City area —Johnson is one of the first doctors to ...
(Date:6/24/2016)... Angeles, CA (PRWEB) , ... June 24, 2016 , ... ... surgery procedures that most people are unfamiliar with. The article goes on to state ... procedures, but also many of these less common operations such as calf and cheek ...
(Date:6/24/2016)... (PRWEB) , ... June 24, 2016 , ... Marcy was in a crisis. Her son ... lash out at his family verbally and physically. , “When something upset him, he couldn’t ... would use it. He would throw rocks at my other children and say he was ...
(Date:6/24/2016)... ... June 24, 2016 , ... Dr. Amanda Cheng, an ... Dr. Cheng has extensive experience with all areas of orthodontics, including robotic Suresmile ... orthodontics. , Micro-osteoperforation is a revolutionary adjunct to orthodontic treatment. It can ...
Breaking Medicine News(10 mins):
(Date:6/24/2016)...  Arkis BioSciences, a leading innovator in the ... cerebrospinal fluid treatments, today announced it has secured ... led by Innova Memphis, followed by Angel Capital ... Arkis, new financing will accelerate the commercialization of ... of its in-licensed Endexo® technology. ...
(Date:6/23/2016)... -- In a startling report released today, National Safety Council ... comprehensive, proven plan to eliminate prescription opioid overdoses. Prescription ... are tackling the worst drug crisis in recorded U.S. history, assigned ... Kentucky , New Mexico , ... 28 failing states, three – Michigan , ...
(Date:6/23/2016)... 23, 2016 Bracket , a leading clinical ... generation clinical outcomes platform, Bracket eCOA (SM) 6.0, at ... 26 – 30, 2016 in Philadelphia , ... Outcome Assessment product of its kind to fully integrate with ... Bracket eCOA 6.0 is a flexible platform for electronic clinical ...
Breaking Medicine Technology: