Navigation Links
Researchers block pathway to cancer cell replication
Date:7/2/2012

Research suggests that patients with leukemia sometimes relapse because standard chemotherapy fails to kill the self-renewing leukemia initiating cells, often referred to as cancer stem cells. In such cancers, the cells lie dormant for a time, only to later begin cloning, resulting in a return and metastasis of the disease.

One such type of cancer is called pediatric T cell acute lymphoblastic leukemia, or T-ALL, often found in children, who have few treatment options beyond chemotherapy.

A team of researchers led by Catriona H. M. Jamieson, MD, PhD, associate professor of medicine at the University of California, San Diego School of Medicine and Director of Stem Cell Research at UC San Diego Moores Cancer Center studied these cells in mouse models that had been transplanted with human leukemia cells. They discovered that the leukemia initiating cells which clone, or replicate, themselves most robustly activate the NOTCH1 pathway, usually in the context of a mutation.

Earlier studies showed that as many as half of patients with T-ALL have mutations in the NOTCH1 pathway an evolutionarily conserved developmental pathway used during differentiation of many cell and tissue types. The new study shows that when NOTCH1 activation was inhibited in animal models using a monoclonal antibody, the leukemia initiating cells did not survive. In addition, the antibody treatment significantly reduced a subset of these cancer stem cells (identified by the presence of specific markers, CD2 and CD7, on the cell surface.)

"We were able to substantially reduce the potential of these cancer stem cells to self-renew," said Jamieson. "So we're not just getting rid of cancerous cells: we're getting to the root of their resistance to treatment leukemic stem cells that lie dormant."

The study results suggest that such therapy would also be effective in other types of cancer stem cells, such as those that cause breast cancer, that also rely on NOTCH1 for self-renewal.

"Therapies based on monoclonal antibodies that inhibit NOTCH 1 are much more selective than using gamma-secretase inhibitors, which also block other essential cellular functions in addition to the NOTCH1 signaling pathway," said contributor A. Thomas Look, MD of Dana-Farber/Children Hospital Cancer Center in Boston. "We are excited about the promise of NOTCH1-specific antibodies to counter resistance to therapy in T-ALL and possibly additional types of cancer."

In investigating the role of NOTCH1 activation in cancer cell cloning, the researchers showed that leukemia initiating cells possess enhanced survival and self-renewal potential in specific blood-cell, or hematopoietic, niches: the microenvironment of the body in which the cells live and self-renew.

The scientists studied the molecular characterization of CD34+ cells a protein that shows expression in early hematopoietic cells and that facilitates cell migration from a dozen T-ALL patient samples.

They found that mutations in NOTCH1 and other genes capable of promoting the survival of cancer stem cells co-existed in the CD34+ niche. Mice transplanted with CD34-enriched NOTCH1 mutated T-ALL cells demonstrated significantly greater leukemic cloning potential than did mice without the NOTCH1 mutation. The mutated cells were uniquely susceptible to targeted inhibition with a human monoclonal antibody, according to the scientists.


'/>"/>

Contact: Debra Kain
ddkain@ucsd.edu
619-543-6163
University of California - San Diego
Source:Eurekalert

Related medicine news :

1. NIH awards $20 million over 5 years to train next generation of global health researchers
2. Researchers develop a new cell and animal model of inflammatory breast cancer
3. Researchers uncover a viable way for colorectal cancer patients to overcome drug resistance
4. Researchers Find Gene Mutations That May Be a Key to Autism
5. Researchers find evidence of banned antibiotics in poultry products
6. NJ stroke researchers report advances in spatial neglect research at AAN Conference
7. Autism by the numbers: Yale researchers examine impact of new diagnostic criteria
8. Researchers Map Brain Regions Linked to Intelligence
9. Researchers ID Genes That May Determine Mental Illness
10. Researchers Develop Blood Test for Depression
11. University of Cincinnati researchers win $3.7M grant from US Department of Defense
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/24/2016)... MIAMI, Fla. (PRWEB) , ... June 24, 2016 , ... ... Florida Trend magazine’s 2016 Legal Elite. The attorneys chosen by their peers for this ... of Florida. , Seven Greenberg Traurig Shareholders received special honors as members of this ...
(Date:6/24/2016)... ... 24, 2016 , ... Comfort Keepers® of San Diego, CA is excited to ... Recovery® program to drive cancer patients to and from their cancer treatments. Comfort ... quality of life and ongoing independence. Getting to and from medical treatments is ...
(Date:6/24/2016)... ... June 24, 2016 , ... People across the U.S. are ... Code Talker Award, an essay contest in which patients and their families pay tribute ... presented at the 2016 National Society of Genetic Counselors (NSGC) Annual Education Conference (AEC) ...
(Date:6/24/2016)... ... 24, 2016 , ... The Haute Beauty Network, affiliated with ... as a prominent plastic surgeon and the network’s newest partner. , Dr. ... handsome men, look naturally attractive. Plastic surgery should be invisible.” He stands by ...
(Date:6/24/2016)... ... June 24, 2016 , ... ... feeding the Frederick area economy by obtaining investment capital for emerging technology companies. ... 2½ years that have already resulted in more than a million dollars of ...
Breaking Medicine News(10 mins):
(Date:6/23/2016)... June 23, 2016 Research and ... Excipients Market by Type (Organic Chemical (Sugar, Petrochemical, Glycerin), ... Topical, Coating, Parenteral) - Global Forecast to 2021" ... The global pharmaceutical excipients market is projected ... CAGR of 6.1% in the forecast period 2016 to ...
(Date:6/23/2016)... -- Research and Markets has announced the addition ... to their offering. The ... commercial environment for MedImmune to enter. The US ageing population ... to drive considerable growth for effective anti-influenza medications. The introduction ... considerably, but development is still in its infancy. ...
(Date:6/23/2016)... -- Revolutionary technology includes multi-speaker listening to ... leaders in advanced audiology and hearing aid technology, has ... the world,s first internet connected hearing aid that opens ...      (Photo: http://photos.prnewswire.com/prnh/20160622/382240 ) , ... firsts,: , TwinLink™ - the first dual ...
Breaking Medicine Technology: