Process triggered by some anti-cancer drugs causes tumors in mice, study finds

which can turn genes on or off, attach to the bases of an organisms DNA.

In many cancer cells, too few methyl molecules attach to DNA, a condition scientists call hypomethylation. But until now, scientists didnt know which came first the cancer or the hypomethylation. Franois Gaudet, a graduate student in Jaenischs lab, spent several years developing mice transgenically designed to be hypomethylated.

It was a shot in the dark to see whether we could generate animals that could actually survive, and at the same time be hypomethylated, said Gaudet.

Gaudets mice expressed only about 10 percent of normal levels of methyltransferase, the enzyme that maintains normal levels of methylation. About 80 percent of the mice developed an aggressive form of leukemia, a tumor that is derived from the thymus. Whats more, the cancer cells detected were the same throughout a tumor, suggesting that the tumor grew from a single hypomethylated abnormal cell. And, in fact, a gene called c-myc, known to be associated with tumor formation, was seen to be overly active in the cells.

Gaudet found that the tumors had an extra copy of chromosome 15, the same chromosome where the c-myc gene is found. This explains higher activity of c-myc, he added. Chromosome aberrations such as trisomies three copies of a chromosome instead of two or chromosome loss are hallmarks of human tumors, particularly leukemia.

Knowing that hypomethylation can cause cancer raises questions about ongoing clinical trials, Gaudet said. The induction of hypomethylation might treat cancer in some tissues but may induce cancer in other tissues, Gaudet said. It is important therefore to test the effect of hypomethylation on cancer in different tissues.

Extending Gaudets work, Amir Eden, a postdoctoral fellow in Jaenischs lab, found that even mice engineered to develop tumors did so earlier when hypomethylated. Edens mice had mutations in genes that normally suppress tumor

Contact: Kelli Whitlock or Melissa Withers
Whitehead Institute for Biomedical Research

Page: 1 2 3

Related biology news :

1. Scientists share multidisciplinary discoveries at Earth System Processes
2. International scientists probe unsolved puzzles of the Earth and beyond at "Earth System Processes"
3. Reproductive Signals Affect Lifespan In Roundworm C. Elegans, Offering Possible Insight Into Human Aging Process
4. Trash From Crop-Processing Plant Harvested For Disease-Fighting Agents
5. Researchers Identify Molecule That May Be Key In Pheromone Processing
6. New Coating Process May Prevent Body From Rejecting Medical Implants
7. Innovative Process To Benefit Ground Water Clean-Up
8. INDOEX Researchers Document The Impact Of Pollutants On Climate Processes Over The Tropical Indian Ocean
9. Reversible Process For Forming Supramolecular Polymers Could Be The Basis Of Fibers, Molecular Transport Mechanisms
10. Common Prostate Cancer: A Different Process Altogether?
11. Penn State Engineers Develop New Simulation For Ultrafine Particle Growth Process

Post Your Comments:

(Date:5/6/2017)... 5, 2017 RAM Group , ... new breakthrough in biometric authentication based on a ... properties to perform biometric authentication. These new sensors are ... created by Ram Group and its partners. This sensor ... supply chains and security. Ram Group is a ...
(Date:4/18/2017)... , April 18, 2017  Socionext Inc., a global expert in ... media edge server, the M820, which features the company,s hybrid codec ... provided by Tera Probe, Inc., will be showcased during the upcoming ... NAB show at the Las Vegas Convention ... Click ...
(Date:4/13/2017)... 13, 2017 According to a new market research ... Analytics, Identity Administration, and Authorization), Service, Authentication Type, Deployment Mode, Vertical, and ... is expected to grow from USD 14.30 Billion in 2017 to USD ... 17.3%. ... MarketsandMarkets Logo ...
Breaking Biology News(10 mins):
(Date:10/10/2017)... , Oct. 10, 2017 International research firm Parks Associates ... will speak at the TMA 2017 Annual Meeting , October 11 ... in the residential home security market and how smart safety and security ... Parks Associates: ... "The residential security ...
(Date:10/9/2017)... , Oct. 9, 2017  BioTech Holdings announced ... by which its ProCell stem cell therapy prevents ... ischemia.  The Company, demonstrated that treatment with ProCell ... limbs saved as compared to standard bone marrow ... HGF resulted in reduction of therapeutic effect.  ...
(Date:10/9/2017)... ... October 09, 2017 , ... ... October 5, 2017, in the medical journal, Epilepsia, Brain Sentinel’s SPEAC® System ... standard, video EEG, in detecting generalized tonic-clonic seizures (GTCS) using surface electromyography ...
(Date:10/6/2017)... ... 06, 2017 , ... The HealthTech Venture Network (HTVN) is ... fourth annual Conference where founders, investors, innovative practitioners and collaborators are invited to ... showcasing early stage digital health and med tech companies. , This day-long event ...
Breaking Biology Technology:
Cached News: