Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Discovery paves the way for a new generation of chemotherapies

10.09.2014

In an article published in the journal Chemistry & Biology, researchers describe a new mechanism that inhibits the activity of proteasomes, protein complexes that are a target for cancer therapy

A new mechanism to inhibit proteasomes, protein complexes that are a target for cancer therapy, is the topic of an article published in the journal Chemistry & Biology. The first author of the study is Daniela Trivella, researcher at the Brazilian Biosciences National Laboratory at the Brazilian Center for Research in Energy and Materials (LNBio/CNPEM).

The findings of the study, conducted with FAPESP support in partnership with researchers from the University of California in San Diego, United States, and at the Technische Universität München, in Germany, are paving the way for the development of a new generation of chemotherapy drugs that are more effective and less toxic.

"We have already developed a series of molecules based on the newly identified mechanism. Now we plan to synthesize them in partnership with CNPEM researcher Marjorie Bruder and test their potential. The goal is to optimize the proteasome inhibition effect, make the compound even more selective of tumor cells and eliminate the resistance problems found with drugs that are currently available on the market," Trivella said.

A member of the category of enzymes known as proteases, the proteasome is a protein complex responsible for several essential functions inside cells, such as eliminating harmful or non-functioning proteins and regulating the processes of apoptosis (programmed cell death), cell division and proliferation.

In 2012, the drug carfilzomib, inspired by a natural molecule called epoxomicin, was approved. Also in 2012, U.S. and Brazilian researchers isolated a natural molecule in cyanobacteria from the Caribbean called carmaphycin, whose reactive group (the portion of the molecule that interacts with the proteasome) is the same as that of carfilzomib. The molecule is known as an epoxyketone.

"Epoxyketones are very potent selective inhibitors of the proteasome because they interact with this enzyme in two stages: the first reversible and the second irreversible," Trivella explained.

To optimize its effect and find new reactive groups, researchers from the Scripps Institution of Oceanography at the University of California in San Diego developed a series of synthetic analogs with slight structural modifications.

Trivella tested these compounds during an internship in California in her post-doctoral research when she was still associated with the Chemistry Institute at the University of Campinas (Unicamp).

One of the molecules tested had an enone as a reactive group and had characteristics of carmaphycin and another natural molecule named syringolin, isolated from plant pathogens.

By investigating the reaction mechanisms of the new molecule, named carmaphycin-syringolin enone, the researcher verified that unlike syringolin, and thus like the epoxyketone, the enone interacts with the proteasome in two stages, with the second stage being irreversible.

Additionally, Trivella had observed that in the case of the enone, the second reaction occurs more slowly, increasing the duration of the reversible phase of carmaphycin-syringolin enone inhibition.

"Because the irreversible inactivation of the proteasome has toxic effects, the best window of reversibility observed for the carmaphycin-syringolin enone will potentially reduce the toxicity of this new class of proteasome inhibitors," Trivella said. "The compound would therefore present a balance between selectivity and potency."

Toxicity tests are still underway. In parallel, studies have been conducted with the help of crystallography techniques to discover exactly how the interaction between the enzyme target and the carmaphycin- syringolin enone target occurs.

"We discovered that a chemical reaction called hydroamination occurs, which had never before seen under physiological conditions. This type of reaction is frequently used by synthetic chemists in preparing substances, but normally it requires very specific temperature and pH conditions and the use of catalysts to occur. It has never been reported as a mechanism of enzyme inhibition," Trivella said.

Inspired by this new mechanism for proteasome inhibition, the LNBio group plans to synthesize and test a new series of carmaphycin-syringolin enone analogs to determine their effects on the therapeutic window (preferential death of tumor cells in relation to healthy cells) and assess whether they are also capable of reacting with proteasomes that are resistant to traditional inhibitors.

Another of Trivella's goals is to look for natural compounds in Brazilian biodiversity that could serve as inspiration for the design of other categories of proteasome inhibitors.

Samuel Antenor | Eurek Alert!
Further information:
http://www.fapesp.br/

Further reports about: chemotherapies compounds death enzyme irreversible mechanism proteasome reactive

More articles from Life Sciences:

nachricht Designer cells: artificial enzyme can activate a gene switch
22.05.2018 | Universität Basel

nachricht Flow of cerebrospinal fluid regulates neural stem cell division
22.05.2018 | Helmholtz Zentrum München - Deutsches Forschungszentrum für Gesundheit und Umwelt

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: LZH showcases laser material processing of tomorrow at the LASYS 2018

At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.

At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...

Im Focus: Self-illuminating pixels for a new display generation

There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?

At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...

Im Focus: Explanation for puzzling quantum oscillations has been found

So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics

Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...

Im Focus: Dozens of binaries from Milky Way's globular clusters could be detectable by LISA

Next-generation gravitational wave detector in space will complement LIGO on Earth

The historic first detection of gravitational waves from colliding black holes far outside our galaxy opened a new window to understanding the universe. A...

Im Focus: Entangled atoms shine in unison

A team led by Austrian experimental physicist Rainer Blatt has succeeded in characterizing the quantum entanglement of two spatially separated atoms by observing their light emission. This fundamental demonstration could lead to the development of highly sensitive optical gradiometers for the precise measurement of the gravitational field or the earth's magnetic field.

The age of quantum technology has long been heralded. Decades of research into the quantum world have led to the development of methods that make it possible...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Save the date: Forum European Neuroscience – 07-11 July 2018 in Berlin, Germany

02.05.2018 | Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

 
Latest News

Designer cells: artificial enzyme can activate a gene switch

22.05.2018 | Life Sciences

PR of MCC: Carbon removal from atmosphere unavoidable for 1.5 degree target

22.05.2018 | Earth Sciences

Achema 2018: New camera system monitors distillation and helps save energy

22.05.2018 | Trade Fair News

VideoLinks
Science & Research
Overview of more VideoLinks >>>