Molecular biologists in the School of Medicine at The University of Texas Health Science Center San Antonio have found a novel way to fine-tune the activity of cells' protein-disposing machinery, with potentially cancer-fighting effects.
This machinery, the proteasome, is deregulated in cancer. Agents called protease inhibitors are viewed as potential anti-cancer therapies, but they indiscriminately curb proteasome activity, which also includes protein recycling. Such strategy is effective to kill cells in aggressive blood cancers but leads to drug resistance and excessive toxicity in solid tumors.
The new strategy may change that. By basically outsmarting the cell's machinery, compounds called allosteric regulators are able to fine-tune the proteasome actions instead of block them. "The result is that cell lines from solid tumors, which are resistant to existing therapy, are sensitive to these agents," said Pawel Osmulski, Ph.D., assistant professor of molecular medicine at the Health Science Center. He and Maria Gaczynska, Ph.D., associate professor of molecular medicine, co-authored a report in Molecular Pharmacology that provides a basis for this approach.
Deregulation of the proteasome's actions is noted in cancer or during aging and contributes to intracellular pathologies. "It is easy to envision that precise adjusting of the proteasome activities with therapeutic molecules would be highly beneficial in many human conditions," Dr. Osmulski said.
Inhibition and activation
"Allosteric regulators are better than proteasome-affecting agents used in clinics because they do not induce classical drug resistance," Dr. Gaczynska said. "They bind to sites on the proteasome molecule used by natural regulatory proteins. They are more specific and are not restricted to proteasome inhibition but can activate the proteasome under certain conditions."
The new strategy was serendipitously found during experiments with rapamycin, a drug that in a highly publicized study by the UT Health Science Center's Barshop Institute for Longevity and Aging Studies was found to extend life span in mice.
The Molecular Pharmacology report and follow-up studies describe the unexpected and highly desired effects that rapamycin and similar compounds elicit on the proteasome. Based on these studies, it would be possible to design a new line of proteasome regulators with anti-cancer properties, Drs. Osmulski and Gaczynska said. This work is in progress in their laboratory. Drs. Osmulski and Gaczynska are affiliated with the Barshop Institute and with the Cancer Therapy & Research Center at The University of Texas Health Science Center San Antonio.The work was supported by the Mike Hogg Fund (to Maria Gaczynska), the William and Ella Owens Medical Research Foundation (to Maria Gaczynska), and the Institute for Integration of Medicine and Science Pilot Grant (to Pawel Osmulski). http://molpharm.aspetjournals.org/content/early/2013/04/25/
On Web and social media
For current news from the UT Health Science Center San Antonio, please visit our news release website, like us on Facebook or follow us on Twitter.
About the UT Health Science Center San Antonio
The University of Texas Health Science Center at San Antonio, one of the country's leading health sciences universities, ranks in the top 3 percent of all institutions worldwide receiving National Institutes of Health funding. The university's schools of medicine, nursing, dentistry, health professions and graduate biomedical sciences have produced approximately 28,000 graduates. The $736 million operating budget supports eight campuses in San Antonio, Laredo, Harlingen and Edinburg. For more information on the many ways "We make lives better®," visit http://www.uthscsa.edu
Will Sansom | EurekAlert!
Why might reading make myopic?
18.07.2018 | Universitätsklinikum Tübingen
Unique brain 'fingerprint' can predict drug effectiveness
11.07.2018 | McGill University
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.
Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
19.07.2018 | Earth Sciences
19.07.2018 | Power and Electrical Engineering
19.07.2018 | Materials Sciences