Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Scientists may be able to double efficacy of radiation therapy

19.12.2011
Scientists may have a way to double the efficacy and reduce the side effects of radiation therapy.

Georgia Health Sciences University scientists have devised a way to reduce lung cancer cells' ability to repair the lethal double-strand DNA breaks caused by radiation therapy.

"Radiation is a great therapy – the problem is the side effects," said Dr. William S. Dynan, biochemist and Associate Director of Research and Chief, Nanomedicine and Gene Regulation at the GHSU Institute of Molecular Medicine and Genetics. "We think this is a way to get the same amount of cancer cell death with less radiation or use the same amount and maybe cure a patient that could not be cured before."

Radiation therapy capitalizes on radiation's ability to kill cells by causing double-strand breaks in DNA. But the fact that varying levels of radiation are essentially everywhere – food, air, the ground, etc. – means all cells, including cancer cells, have internal mechanisms to prevent the lethal breakage.

GHSU scientists are targeting the natural defense mechanisms by packaging a piece of an antibody against one of them with folate, which has easy access to most cells, particularly cancer cells. Many cancers, including the lung cancer cells they studied, have large numbers of folate receptors so that cancer cells get a disproportionate share of the package.

Previous efforts to destroy cancer cells' ability to avoid radiation damage have focused on receptors on their surface, said Dr. Shuyi Li, molecular biologist, pediatrician and corresponding author on the study in the International Journal of Radiation Oncology.

To get a more direct hit, the scientists took advantage of folate receptors as a point of entry by chemically binding folate with the small piece of their antibody, ScFv 18-2. The package heads straight for the cell nucleus where a different chemical environment breaks the bond, freeing ScFv 18-2 to attack the regulatory region of DNA-dependent protein kinase, an enzyme essential to DNA repair.

"We are joining a targeting molecule with a cargo," said Dynan. "This strategy targets one of the key enzymes so it's harder to repair," Li said. This makes cancer cells more vulnerable to radiation.

Dynan and Li say the approach could be used to deliver any number of drugs directly inside cancer cells. Future studies include looking at other cell entry points as well as other targets to ensure they have the most effective package. Studies to date have been in human lung cancer cells in culture, so next steps also need to include animal studies.

Their approach mimics a natural process called endocytosis in which cells engulf proteins and other substances they want to let inside but can't fit through normal doorways.

Folate receptors already are being used as direct entry points for chemotherapeutic drugs, including clinical studies of a new strategy for ovarian cancer. GHSU is participating in clinical trials of a therapy that pairs an agent too toxic to be delivered through the bloodstream with folate to better target one of the most deadly cancers.

Dynan is the Georgia Research Alliance Eminent Scholar in Molecular Biology. Dynan and Li are both faculty members in GHSU's Medical College of Georgia. Dynan also is a faculty member in the College of Graduate Studies.

Toni Baker | EurekAlert!
Further information:
http://www.georgiahealth.edu

More articles from Health and Medicine:

nachricht Usher syndrome: Gene therapy restores hearing and balance
25.09.2017 | Institut Pasteur

nachricht MRI contrast agent locates and distinguishes aggressive from slow-growing breast cancer
25.09.2017 | Case Western Reserve University

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

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

Im Focus: The fastest light-driven current source

Controlling electronic current is essential to modern electronics, as data and signals are transferred by streams of electrons which are controlled at high speed. Demands on transmission speeds are also increasing as technology develops. Scientists from the Chair of Laser Physics and the Chair of Applied Physics at Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) have succeeded in switching on a current with a desired direction in graphene using a single laser pulse within a femtosecond ¬¬ – a femtosecond corresponds to the millionth part of a billionth of a second. This is more than a thousand times faster compared to the most efficient transistors today.

Graphene is up to the job

Im Focus: LaserTAB: More efficient and precise contacts thanks to human-robot collaboration

At the productronica trade fair in Munich this November, the Fraunhofer Institute for Laser Technology ILT will be presenting Laser-Based Tape-Automated Bonding, LaserTAB for short. The experts from Aachen will be demonstrating how new battery cells and power electronics can be micro-welded more efficiently and precisely than ever before thanks to new optics and robot support.

Fraunhofer ILT from Aachen relies on a clever combination of robotics and a laser scanner with new optics as well as process monitoring, which it has developed...

Im Focus: The pyrenoid is a carbon-fixing liquid droplet

Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.

A warming planet

Im Focus: Highly precise wiring in the Cerebral Cortex

Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.

The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...

Im Focus: Tiny lasers from a gallery of whispers

New technique promises tunable laser devices

Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

Nerves control the body’s bacterial community

26.09.2017 | Life Sciences

Four elements make 2-D optical platform

26.09.2017 | Physics and Astronomy

Goodbye, login. Hello, heart scan

26.09.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>