Featured Research

from universities, journals, and other organizations

A stop sign for cancer

Date:
December 13, 2013
Source:
Veterinärmedizinische Universität Wien
Summary:
A particularly aggressive form of leukemia is the acute lymphoblastic leukemia (ALL). It is especially common among children and very difficult to treat. Researchers have now discovered completely new targets for the treatment of blood cancers. Studying the cancer protein STAT5, the scientists found new opportunities for the development of effective anti-cancer drugs.

The left image shows aktivated STAT5. Cancer cells grow. In the right image, PAK is inhibited, STAT5 is therefore no longer active and cancer cells die.
Credit: Angelika Berger / Vetmeduni Vienna

A particularly aggressive form of leukemia is the acute lymphoblastic leukemia (ALL). It is especially common among children and very difficult to treat. Researchers from the University of Veterinary Medicine, Vienna have now discovered completely new targets for the treatment of blood cancers. Studying the cancer protein STAT5, the scientists found new opportunities for the development of effective anti-cancer drugs. The research team published the scientific work, which could also become relevant for other types of cancer, in the Journal Leukemia.

Proteins in cells communicate like relay runners in a competition. The sticks that are transferred between the runners are the "signals." These signals are passed within the cell from one protein to another and ensure cell growth and survival. In cancer cells it is interesting approach to block this information cascade and thereby block the proliferation of cancer cells.

Essential for the signalling in cancer cells is the protein STAT5. It is known that STAT5 is overstimulated in many cancers. It forwards signals in an uncontrolled manner and is ultimately responsible for the excessive cell division of cancer cells. In mice that suffer from leukemia, it has already been shown, that the elimination of STAT5 makes the animals gain health again. Therefore, the importance of the protein in cancer is obvious. The researchers now want to apply this information on cancer therapy in humans.

Slowing down STAT5

The research team led by Veronika Sexl from the Institute of Pharmacology and Toxicology at the Vetmeduni Vienna took a closer look at STAT5. Using leukemia as a model disease, the team looked for therapeutically exploitable attack points on the protein and they actually identified such. The shutdown of two distinct signals of STAT5 led to a significantly later progression of leukemia in mice compared to animals that harbored the unmodified STAT5. One of these two therapeutically relevant sites is of particular importance: "The shutdown of the site Serin779 on STAT5 makes it impossible for STAT5 to fulfil its role as a relay runner and migrate into the nucleus. Thus, the effect of STAT5 is inhibited," says Hölbl-Kovacic, one of the lead authors of the pioneering publication.

Interrupting the relay race at several points

In a large-scale screening, the co-lead author Angelika Berger identified those relay runners that act before Serin779, the so-called PAK (p21 activated kinase). This means that PAK has control over STAT5 and activates it. By inhibiting PAK, STAT5 is turned off and disconnected from the relay race. The cancer researchers also found that PAK is still active, when cancer cells have already been treated with the current standard therapeutic agent Imatinib. This means that a potential new drug that acts on PAK could be well used in combination with Imatinib. Such a strategy would be of great importance in patients that no longer respond to Imatinib and are "therapy-resistant." PAK kinases thus represent a new therapeutic target, which is independent of previous treatment methods.

STAT5 has a role in many cancers

Angelika Berger explains: "So far, the PAK kinases have received relatively little attention in cancer therapy. However, they could be beneficial for a wide range of applications. All types of cancers, in which STAT5 plays a role, could be treated by this system in a new way. Those are the leukemias but also a number of other diseases such as breast cancer or prostate cancer."


Story Source:

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


Journal Reference:

  1. A Berger, A Hoelbl-Kovacic, J Bourgeais, L Hoefling, W Warsch, E Grundschober, I Z Uras, I Menzl, E M Putz, G Hoermann, C Schuster, S Fajmann, E Leitner, S Kubicek, R Moriggl, F Gouilleux, V Sexl. PAK-dependent STAT5 serine phosphorylation is required for BCR-ABL-induced leukemogenesis. Leukemia, 2013; DOI: 10.1038/leu.2013.351

Cite This Page:

Veterinärmedizinische Universität Wien. "A stop sign for cancer." ScienceDaily. ScienceDaily, 13 December 2013. <www.sciencedaily.com/releases/2013/12/131213093306.htm>.
Veterinärmedizinische Universität Wien. (2013, December 13). A stop sign for cancer. ScienceDaily. Retrieved September 20, 2014 from www.sciencedaily.com/releases/2013/12/131213093306.htm
Veterinärmedizinische Universität Wien. "A stop sign for cancer." ScienceDaily. www.sciencedaily.com/releases/2013/12/131213093306.htm (accessed September 20, 2014).

Share This



More Health & Medicine News

Saturday, September 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Could Grief Affect The Immune Systems Of Senior Citizens?

Could Grief Affect The Immune Systems Of Senior Citizens?

Newsy (Sep. 19, 2014) — The study found elderly people are much more likely to become susceptible to infection than younger adults going though a similar situation. Video provided by Newsy
Powered by NewsLook.com
Jury Delivers Verdict in Salmonella Trial

Jury Delivers Verdict in Salmonella Trial

AP (Sep. 19, 2014) — A federal jury has convicted three people in connection with an outbreak of salmonella poisoning five years ago that sickened hundreds of people and was linked to a number of deaths. (Sept. 19) Video provided by AP
Powered by NewsLook.com
How The 'Angelina Jolie Effect' Increased Cancer Screenings

How The 'Angelina Jolie Effect' Increased Cancer Screenings

Newsy (Sep. 19, 2014) — Angelina's Jolie's decision to undergo a preventative mastectomy in 2013 inspired many women to seek early screenings for the disease. Video provided by Newsy
Powered by NewsLook.com
The Cost of Ebola

The Cost of Ebola

Reuters - Business Video Online (Sep. 18, 2014) — As Sierra Leone prepares for a three-day "lockdown" in its latest bid to stem the spread of Ebola, Ciara Lee looks at the financial implications of fighting the largest ever outbreak of the disease. Video provided by Reuters
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