Featured Research

from universities, journals, and other organizations

Cell mechanism that reduces effectiveness of breast cancer treatment identified

Date:
October 19, 2011
Source:
Elhuyar Fundazioa
Summary:
Researchers have discovered a complex cell mechanism activated by a protein --HOXB9-- that becomes an obstacle for radiation effectiveness.

Researchers from Massachusetts General Hospital, Harvard Medical School and CIC bioGUNE discover a complex cell mechanism activated by a protein -- HOXB9 -- that becomes an obstacle for radiation effectiveness.

Scientists all over the world continue to focus their research on breast cancer. As a consequence, knowledge of the behaviour of tumour cells is growing, as well as of their interactions with the microenvironment. There are, however, many questions still unanswered.

A new collaborative study carried out by the laboratory of Dr Marνa Vivanco, researcher at the Cell Biology and Stem Cells Unit in the Center for Cooperative Research in Biosciences, CIC bioGUNE, and the groups led by Dr Zou and Dr Maheswaran in Boston, has provided insight into one of these mysteries: a cell mechanism that explains how a protein -- called HOXB9 -- helps cancer cells to avoid the attack of treatments such as radiation, and prevents the therapy from having the desired effect on certain types of breast cancer.

The study was recently published in Proceedings of the National Academy of Sciences (PNAS). The study shows that cells that express higher levels of the HOXB9 transcription factor are more likely to survive the radiation used as breast cancer treatment.

A complex mechanism induced by this protein has been discovered, which manages to activate a whole chain of cell processes in which different proteins -- such as ATM kinase, amongst others -- intervene, and which make certain cancerous cells more resistant to treatment. Dr Vivanco explains, "when the tumour is exposed to radiation it induces DNA damage -- a phenomenon that results in formation of double-stranded DNA breaks -- leading the cells to respond and try to repair the damage caused in the DNA using another mechanism -- called the DNA damage response," by activating ATM kinase. In this way, the cell cycle is stopped and the DNA is repaired in order to maintain chromosome stability.

HOXB9 expression causes an increase in survival of cells that have been exposed to radiation. This higher resistance occurs because of the acceleration of response to radiation and its higher recovery capacity after DNA damage. On the other hand, reduction of the levels of this protein, leads to increased cell sensitivity to radiation. Furthermore, the growth factor TGFbeta (a HOXB9 target) is also involved. Therefore, HOXB9 facilitates DNA repair by activation of the TGFbeta signalling pathway, which elevates ATM phosphorylation, accelerates DNA damage response and radiation resistance.

The published research is the continuation of another study carried out last year by CIC bioGUNE, Massachusetts General Hospital and Harvard Medical School, which showed that this same protein (HOXB9) is overexpressed in breast cancer and that its expression levels are associated with high tumour grade.


Story Source:

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


Journal Reference:

  1. N. Chiba, V. Comaills, B. Shiotani, F. Takahashi, T. Shimada, K. Tajima, D. Winokur, T. Hayashida, H. Willers, E. Brachtel, M. d. M. Vivanco, D. A. Haber, L. Zou, S. Maheswaran. Breast Cancer Special Feature: Homeobox B9 induces epithelial-to-mesenchymal transition-associated radioresistance by accelerating DNA damage responses. Proceedings of the National Academy of Sciences, 2011; DOI: 10.1073/pnas.1018867108

Cite This Page:

Elhuyar Fundazioa. "Cell mechanism that reduces effectiveness of breast cancer treatment identified." ScienceDaily. ScienceDaily, 19 October 2011. <www.sciencedaily.com/releases/2011/10/111019104533.htm>.
Elhuyar Fundazioa. (2011, October 19). Cell mechanism that reduces effectiveness of breast cancer treatment identified. ScienceDaily. Retrieved August 21, 2014 from www.sciencedaily.com/releases/2011/10/111019104533.htm
Elhuyar Fundazioa. "Cell mechanism that reduces effectiveness of breast cancer treatment identified." ScienceDaily. www.sciencedaily.com/releases/2011/10/111019104533.htm (accessed August 21, 2014).

Share This




More Health & Medicine News

Thursday, August 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Drug Used To Treat 'Ebola's Cousin' Shows Promise

Drug Used To Treat 'Ebola's Cousin' Shows Promise

Newsy (Aug. 21, 2014) — An experimental drug used to treat Marburg virus in rhesus monkeys could give new insight into a similar treatment for Ebola. Video provided by Newsy
Powered by NewsLook.com
Cadavers, a Teen, and a Medical School Dream

Cadavers, a Teen, and a Medical School Dream

AP (Aug. 21, 2014) — Contains graphic content. He's only 17. But Johntrell Bowles has wanted to be a doctor from a young age, despite the odds against him. He was recently the youngest participant in a cadaver program at the Indiana University NW medical school. (Aug. 21) Video provided by AP
Powered by NewsLook.com
Possible Ebola Patient in Isolation at California Hospital

Possible Ebola Patient in Isolation at California Hospital

Reuters - US Online Video (Aug. 20, 2014) — A patient who may have been exposed to the Ebola virus is in isolation at the Kaiser Permanente South Sacramento Medical Center. Linda So reports. Video provided by Reuters
Powered by NewsLook.com
Reasons Why Teen Birth Rates Are At An All-Time Low

Reasons Why Teen Birth Rates Are At An All-Time Low

Newsy (Aug. 20, 2014) — A CDC report says birth rates among teenagers have been declining for decades, reaching a new low in 2013. We look at several popular explanations. Video provided by Newsy
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