Featured Research

from universities, journals, and other organizations

Dysfunctional mitochondria may underlie resistance to radiation therapy

Date:
November 25, 2013
Source:
University of Illinois at Chicago
Summary:
The resistance of some cancers to the cell-killing effects of radiation therapy may be due to abnormalities in the mitochondria -- the cellular structures responsible for generating energy, according to an international team of researchers.

The resistance of some cancers to the cell-killing effects of radiation therapy may be due to abnormalities in the mitochondria -- the cellular structures responsible for generating energy, according to an international team of researchers. Their findings are published in the Nov. 25 issue of Developmental Cell.

Maxim Frolov, associate professor of biochemistry and molecular genetics at the University of Illinois at Chicago, and colleagues investigated the effects of a mutation in a gene called E2F, which controls other genes responsible for initiating programmed cell death, a normal function in most cells. Cells undergo programmed cell death -- or apoptosis -- when they are no longer needed, as a normal part of aging, or in response to environmental factors like radiation that damage cellular DNA.

When Frolov and colleagues exposed fruit flies carrying a mutant E2F gene to radiation, genes that initiate apoptosis were activated, but the flies did not die.

"Something else was preventing the flies from dying, even though the genes needed to undergo cell death were turned on," Frolov said.

A closer look within the cells of the flies revealed that their mitochondria were misshapen and produced less energy than normal mitochondria. Flies with the most severely deranged mitochondria were the most resistant to radiation-induced cell death.

The observation in fruit flies suggested a previously unknown role for the E2F transcription factor -- the protein encoded by E2F that regulates expression of other genes -- in mitochondrial function.

"It seems their mitochondria were also affected by the E2F mutation and were not functioning at full strength," said Frolov. "You need properly functioning mitochondria to carry out programmed cell death."

Turning to human cells, the researchers found the same effects: those that lacked the E2F gene were resistant to the effects of radiation. Frolov said the similarity in the findings shows that basic cellular functions do not change much across the vast evolutionary distance between fruit flies and humans.

"This result highlights a remarkable degree of conservation between fruit flies and humans and illustrates the advantages of using model organisms in cancer research," said Frolov, whose laboratory is part of the UIC Cancer Center.

Frolov and his colleagues think that dysfunctional mitochondria might underlie the differences in how patients respond to radiation therapy. Previous studies have suggested that the inability of some patients' mitochondria to support apoptosis might account for differences in their response to chemotherapy for acute myelogenous leukemia.

"If we could develop a small-molecule drug that could enhance mitochondrial function in these patients, we may be able to improve the effectiveness of radiation therapy," Frolov said.


Story Source:

The above story is based on materials provided by University of Illinois at Chicago. Note: Materials may be edited for content and length.


Journal Reference:

  1. Aaron M. Ambrus, Abul B.M.M.K. Islam, Katherine B. Holmes, Nam Sung Moon, Nuria Lopez-Bigas, Elizaveta V. Benevolenskaya, Maxim V. Frolov. Loss of dE2F Compromises Mitochondrial Function. Developmental Cell, 2013; 27 (4): 438 DOI: 10.1016/j.devcel.2013.10.002

Cite This Page:

University of Illinois at Chicago. "Dysfunctional mitochondria may underlie resistance to radiation therapy." ScienceDaily. ScienceDaily, 25 November 2013. <www.sciencedaily.com/releases/2013/11/131125121708.htm>.
University of Illinois at Chicago. (2013, November 25). Dysfunctional mitochondria may underlie resistance to radiation therapy. ScienceDaily. Retrieved August 20, 2014 from www.sciencedaily.com/releases/2013/11/131125121708.htm
University of Illinois at Chicago. "Dysfunctional mitochondria may underlie resistance to radiation therapy." ScienceDaily. www.sciencedaily.com/releases/2013/11/131125121708.htm (accessed August 20, 2014).

Share This




More Health & Medicine News

Wednesday, August 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

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
Raw: World's Oldest Man Lives in Japan

Raw: World's Oldest Man Lives in Japan

AP (Aug. 20, 2014) — A 111-year-old Japanese was certified as the world's oldest man by Guinness World Records on Wednesday. Sakari Momoi, a native of Fukushima in northern Japan, was given a certificate at a hospital in Tokyo. (Aug. 20) Video provided by AP
Powered by NewsLook.com
Do More Wedding Guests Make A Happier Marriage?

Do More Wedding Guests Make A Happier Marriage?

Newsy (Aug. 20, 2014) — A new study found couples who had at least 150 guests at their weddings were more likely to report being happy in their marriages. Video provided by Newsy
Powered by NewsLook.com
Ebola-Hit Sierra Leone's Freetown a City on Edge

Ebola-Hit Sierra Leone's Freetown a City on Edge

AFP (Aug. 19, 2014) — Residents of Sierra Leone's capital voice their fears as the Ebola virus sweeps through west Africa. Duration: 00:56 Video provided by AFP
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