Featured Research

from universities, journals, and other organizations

Tumor suppressor is needed for stem cells to mature into neurons

Date:
August 12, 2013
Source:
Karolinska Institutet
Summary:
The previously proposed tumor suppressor CHD5 is essential for making nervous system stem cells mature into neurons, according to a new study. The finding provides valuable information about how neurons mature and shows why the loss of CHD5 can make tumors of the nerve system more malignant.

CHD5 has previously been proposed as a tumour suppressor, acting as a brake that prevents healthy cells from developing into cancer cells. But the part played by the protein in healthy tissue, and whether this role is important for its ability to counter tumour growth, has remained largely uncharted. Working with colleagues at Trinity College in Dublin and BRIC in Copenhagen, researchers at Karolinska Institutet have revealed its function in normal nervous system development and as a tumour suppressor.

The recently published study shows that when stem cells approach the final phase of their specialisation as neurons, CHD5 begins to be expressed at high levels. CHD5 can reshape the chromatin, in which DNA is packed around proteins, and in so doing either facilitate or obstruct the expression of genes. Ulrika Nyman, postdoc researcher in Dr Johan Holmberg's research group and one of the main authors of the current study, explains that on switching off CHD5 in the stem cells of mice embryos during the period in which the brain develops and the majority of neurons are formed, they found was that without CHD5, a stem cell is unable to silence the expression of a number of stem cell genes and genes that are actually to be expressed in muscle, blood or intestinal cells. They also observed an inability in the stem cell to switch on the expression of genes necessary for it to mature into a neuron, leaving it trapped in a stage between stem cell and neuron.

The gene that codes for CHD5 is found on part of chromosome 1 (1p36), which is often lost in tumour cells in a number of cancers, particularly neuroblastoma, a disease that strikes almost only children and which is thought to arise during the development of the peripheral nervous system. Neuroblastoma lacking this section of chromosome and thus also CHD5 are often more aggressive and more rapidly fatal. Treatment with retinoic acid can make immature nerve cells and some neuroblastoma cells mature into specialised nerve cells, but when the researchers prevented neuroblastoma cells from upregulating CHD5, the tumours no longer responded to retinoic acid treatment.

"In the absence of CHD5, neural tumour cells cannot mature into harmless neurons, but continue to divide, making the tumour more malignant and much harder to treat," says Dr Holmberg at the Department of Cell and Molecular Biology. "We now hope to be able to restore the ability to upregulate CHD5 in aggressive tumour cells and make them mature into harmless nerve cells."


Story Source:

The above story is based on materials provided by Karolinska Institutet. Note: Materials may be edited for content and length.


Journal Reference:

  1. Chris M. Egan, Ulrika Nyman, Julie Skotte, Gundula Streubel, Siobhán Turner, David J. O’Connell, Vilma Rraklli, Michael J. Dolan, Naomi Chadderton, Klaus Hansen, Gwyneth Jane Farrar, Kristian Helin, Johan Holmberg, Adrian P. Bracken. CHD5 Is Required for Neurogenesis and Has a Dual Role in Facilitating Gene Expression and Polycomb Gene Repression. Developmental Cell, 2013; 26 (3): 223 DOI: 10.1016/j.devcel.2013.07.008

Cite This Page:

Karolinska Institutet. "Tumor suppressor is needed for stem cells to mature into neurons." ScienceDaily. ScienceDaily, 12 August 2013. <www.sciencedaily.com/releases/2013/08/130812170331.htm>.
Karolinska Institutet. (2013, August 12). Tumor suppressor is needed for stem cells to mature into neurons. ScienceDaily. Retrieved July 23, 2014 from www.sciencedaily.com/releases/2013/08/130812170331.htm
Karolinska Institutet. "Tumor suppressor is needed for stem cells to mature into neurons." ScienceDaily. www.sciencedaily.com/releases/2013/08/130812170331.htm (accessed July 23, 2014).

Share This




More Health & Medicine News

Wednesday, July 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Courts Conflicted Over Healthcare Law

Courts Conflicted Over Healthcare Law

AP (July 22, 2014) — Two federal appeals courts issued conflicting rulings Tuesday on the legality of the federally-run healthcare exchange that operates in 36 states. (July 22) Video provided by AP
Powered by NewsLook.com
Why Do People Believe We Only Use 10 Percent Of Our Brains?

Why Do People Believe We Only Use 10 Percent Of Our Brains?

Newsy (July 22, 2014) — The new sci-fi thriller "Lucy" is making people question whether we really use all our brainpower. But, as scientists have insisted for years, we do. Video provided by Newsy
Powered by NewsLook.com
Scientists Find New Way To Make Human Platelets

Scientists Find New Way To Make Human Platelets

Newsy (July 22, 2014) — Boston scientists have discovered a new way to create fully functioning human platelets using a bioreactor and human stem cells. Video provided by Newsy
Powered by NewsLook.com
Gilead's $1000-a-Pill Drug Could Cure Hep C in HIV-Positive People

Gilead's $1000-a-Pill Drug Could Cure Hep C in HIV-Positive People

TheStreet (July 21, 2014) — New research shows Gilead Science's drug Sovaldi helps in curing hepatitis C in those who suffer from HIV. In a medical study, the combination of Gilead's Hep C drug with anti-viral drug Ribavirin cured 76% of HIV-positive patients suffering from the most common hepatitis C strain. Hepatitis C and related complications have been a top cause of death in HIV-positive patients. Typical medication used to treat the disease, including interferon proteins, tended to react badly with HIV drugs. However, Sovaldi's %1,000-a-pill price tag could limit the number of patients able to access the treatment. TheStreet's Keris Lahiff reports from New York. Video provided by TheStreet
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins