Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New Strategy Directly Activates Cellular ‘Death Protein’

04.06.2012
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.

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.

The research was funded by the William Lawrence and Blanche Hughes Foundation, with additional support provided by grants from the National Institutes of Health (grants 4R00HL095929 and 5R01CA050239) and Stand Up To Cancer.

Dana-Farber Cancer Institute (www.dana-farber.org) is a principal teaching affiliate of the Harvard Medical School and is among the leading cancer research and care centers in the United States. It is a founding member of the Dana-Farber/Harvard Cancer Center (DF/HCC), designated a comprehensive cancer center by the National Cancer Institute. It provides adult cancer care with Brigham and Women’s Hospital as Dana-Farber/Brigham and Women’s Cancer Center and it provides pediatric care with Children’s Hospital Boston as Dana-Farber/Children’s Hospital Cancer Center. Dana-Farber is the top ranked cancer center in New England, according to U.S. News & World Report, and one of the largest recipients among independent hospitals of National Cancer Institute and National Institutes of Health grant funding. Follow Dana-Farber on Twitter: @danafarber or Facebook: facebook.com/danafarbercancerinstitute.

| Newswise Science News
Further information:
http://www.dana-farber.org

Further reports about: BAM7 Cancer Dana-Farber cell death death protein normal cells proteins

More articles from Life Sciences:

nachricht Chip-based optical sensor detects cancer biomarker in urine
05.12.2019 | The Optical Society

nachricht Scientist identify new marker for insecticide resistance in malaria mosquitoes
05.12.2019 | Liverpool School of Tropical Medicine

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: The coldest reaction

With ultracold chemistry, researchers get a first look at exactly what happens during a chemical reaction

The coldest chemical reaction in the known universe took place in what appears to be a chaotic mess of lasers. The appearance deceives: Deep within that...

Im Focus: How do scars form? Fascia function as a repository of mobile scar tissue

Abnormal scarring is a serious threat resulting in non-healing chronic wounds or fibrosis. Scars form when fibroblasts, a type of cell of connective tissue, reach wounded skin and deposit plugs of extracellular matrix. Until today, the question about the exact anatomical origin of these fibroblasts has not been answered. In order to find potential ways of influencing the scarring process, the team of Dr. Yuval Rinkevich, Group Leader for Regenerative Biology at the Institute of Lung Biology and Disease at Helmholtz Zentrum München, aimed to finally find an answer. As it was already known that all scars derive from a fibroblast lineage expressing the Engrailed-1 gene - a lineage not only present in skin, but also in fascia - the researchers intentionally tried to understand whether or not fascia might be the origin of fibroblasts.

Fibroblasts kit - ready to heal wounds

Im Focus: McMaster researcher warns plastic pollution in Great Lakes growing concern to ecosystem

Research from a leading international expert on the health of the Great Lakes suggests that the growing intensity and scale of pollution from plastics poses serious risks to human health and will continue to have profound consequences on the ecosystem.

In an article published this month in the Journal of Waste Resources and Recycling, Gail Krantzberg, a professor in the Booth School of Engineering Practice...

Im Focus: Machine learning microscope adapts lighting to improve diagnosis

Prototype microscope teaches itself the best illumination settings for diagnosing malaria

Engineers at Duke University have developed a microscope that adapts its lighting angles, colors and patterns while teaching itself the optimal...

Im Focus: Small particles, big effects: How graphene nanoparticles improve the resolution of microscopes

Conventional light microscopes cannot distinguish structures when they are separated by a distance smaller than, roughly, the wavelength of light. Superresolution microscopy, developed since the 1980s, lifts this limitation, using fluorescent moieties. Scientists at the Max Planck Institute for Polymer Research have now discovered that graphene nano-molecules can be used to improve this microscopy technique. These graphene nano-molecules offer a number of substantial advantages over the materials previously used, making superresolution microscopy even more versatile.

Microscopy is an important investigation method, in physics, biology, medicine, and many other sciences. However, it has one disadvantage: its resolution is...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

The Future of Work

03.12.2019 | Event News

First International Conference on Agrophotovoltaics in August 2020

15.11.2019 | Event News

Laser Symposium on Electromobility in Aachen: trends for the mobility revolution

15.11.2019 | Event News

 
Latest News

Detailed insight into stressed cells

05.12.2019 | Life Sciences

State of 'hibernation' keeps haematopoietic stem cells young - Niches in the bone marrow protect from ageing

05.12.2019 | Life Sciences

First field measurements of laughing gas isotopes

05.12.2019 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>