Featured Research

from universities, journals, and other organizations

New strategy directly activates cellular 'death protein'

Date:
May 31, 2012
Source:
Dana-Farber Cancer Institute
Summary:
Researchers have devised a strategy to directly activate a natural "death" protein, triggering the self-destruction of cells -- which could lead to new possibilities for designing cancer drugs.

Researchers at Dana-Farber/Children's Hospital Cancer Center have devised a strategy to directly activate a natural "death" protein, triggering the self-destruction of cells. They say the development could represent a new paradigm for designing cancer drugs.

Related Articles


In an article published as an advanced online publication by Nature Chemical Biology, scientists led by Loren Walensky, MD, PhD, report they identified a prototype compound that "flips a switch" to directly activate one of the most powerful death proteins, known as BAX, triggering apoptosis, or self-destruction of unwanted cells.

"Having identified the 'on switch' for the BAX protein several years ago, we now have a small molecule that can directly turn this death protein on," says Walensky, senior author of the report. The first author, Evripidis Gavathiotis, PhD, carried out the work in Walensky's laboratory; currently he is an assistant professor at Albert Einstein College of Medicine in New York.

The development exploited the discovery by Walensky's team of a distinctive groove, or "trigger site," on the BAX protein that converts it from a quiescent form to an active one. When activated, BAX damages the cell's mitochondria, releasing signals that break the cell apart and digest its pieces. This process of programmed cell death is part of a natural check-and-balance mechanism to control cellular life and death.

In search of molecular compounds that could fit snugly into the trigger site and jump-start BAX, the investigators used computer-based screening to sift through 750,000 small molecules from commercially available libraries.

The search paid off with the identification of a small-molecule compound named BAM7 (BAX Activator Molecule 7), which selectively bound to BAX and flipped its "on switch," turning it into an active death protein.

"A small molecule has never been identified before to directly activate BAX and induce cell death in precisely this way," explains Gavathiotis. "Because BAX is a critical control point for regulating cell death, being able to target it selectively opens the door to a new therapeutic strategy for cancer and perhaps other diseases of cellular excess."

But wouldn't switching on cell-death proteins in a patient kill normal cells as well? The researchers say that other compounds now in clinical trials that target the apoptosis pathway haven't shown such side effects. Gavathiotis suggests that there are sufficient extra survival proteins in normal cells to protect them against pro-death BAX. Cancer cells, however, are under stress and their survival mechanism is stretched to the limit, so that an attack by BAX pushes the cells over the brink into self-destruction.

The Walensky group has previously developed other compounds designed to spur apoptosis of cancer cells. These agents do so either by blocking "anti-death" proteins, deployed by cancer cells to prevent BAX and other death molecules from carrying out their assignment, or by blocking both "anti-death" proteins and activating "pro-death proteins" simultaneously. BAM7 is the first compound that avoids combat with cancer cell's survival proteins and binds directly and selectively to BAX to turn on cell death.

"We find that small molecule targeting of the BAX trigger site is achievable and could lead to a new generation of apoptotic modulators that directly activate BCL-2 executioner proteins in cancer and other diseases driven by pathologic apoptotic blockades," write the authors.

Walensky and his colleagues continue to work on BAM7, which is a prototype of drugs that might one day be approved for cancer treatment. Several biotechnology companies have already expressed interest in developing the compound, he says.

Other authors from Walensky's Dana-Farber lab are Denis Reyna, Joseph Bellairs, and Elizaveta Leshchiner.


Story Source:

The above story is based on materials provided by Dana-Farber Cancer Institute. Note: Materials may be edited for content and length.


Journal Reference:

  1. Evripidis Gavathiotis, Denis E Reyna, Joseph A Bellairs, Elizaveta S Leshchiner, Loren D Walensky. Direct and selective small-molecule activation of proapoptotic BAX. Nature Chemical Biology, 2012; DOI: 10.1038/nchembio.995

Cite This Page:

Dana-Farber Cancer Institute. "New strategy directly activates cellular 'death protein'." ScienceDaily. ScienceDaily, 31 May 2012. <www.sciencedaily.com/releases/2012/05/120531135743.htm>.
Dana-Farber Cancer Institute. (2012, May 31). New strategy directly activates cellular 'death protein'. ScienceDaily. Retrieved December 20, 2014 from www.sciencedaily.com/releases/2012/05/120531135743.htm
Dana-Farber Cancer Institute. "New strategy directly activates cellular 'death protein'." ScienceDaily. www.sciencedaily.com/releases/2012/05/120531135743.htm (accessed December 20, 2014).

Share This


More From ScienceDaily



More Health & Medicine News

Saturday, December 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

The Best Tips to Curb Holiday Carbs

The Best Tips to Curb Holiday Carbs

Buzz60 (Dec. 19, 2014) It's hard to resist those delicious but fattening carbs we all crave during the winter months, but there are some ways to stay satisfied without consuming the extra calories. Vanessa Freeman (@VanessaFreeTV) has the details. Video provided by Buzz60
Powered by NewsLook.com
Sierra Leone Bikers Spread the Message to Fight Ebola

Sierra Leone Bikers Spread the Message to Fight Ebola

AFP (Dec. 19, 2014) More than 100 motorcyclists hit the road to spread awareness messages about Ebola. Nearly 7,000 people have now died from the virus, almost all of them in west Africa, according to the World Health Organization. Video provided by AFP
Powered by NewsLook.com
Researchers Test Colombian Village With High Alzheimer's Rates

Researchers Test Colombian Village With High Alzheimer's Rates

AFP (Dec. 19, 2014) In Yarumal, a village in N. Colombia, Alzheimer's has ravaged a disproportionately large number of families. A genetic "curse" that may pave the way for research on how to treat the disease that claims a new victim every four seconds. Duration: 02:42 Video provided by AFP
Powered by NewsLook.com
Double-Amputee Becomes First To Move Two Prosthetic Arms With His Mind

Double-Amputee Becomes First To Move Two Prosthetic Arms With His Mind

Buzz60 (Dec. 19, 2014) A double-amputee makes history by becoming the first person to wear and operate two prosthetic arms using only his mind. Jen Markham has the story. Video provided by Buzz60
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:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

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