Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Researchers identify immune dysfunction in melanoma patients

08.05.2007
Researchers at the Stanford University School of Medicine have begun to shed light on why the human immune system isn't able to stop such cancers as melanoma, suggesting answers that could pave the way for better treatment of this often-fatal illness.

In a small study, the scientists found that the immune cells in a majority of people with this deadly skin cancer fail to respond properly to a molecule called interferon, which normally activates the immune system. Without the ability to respond to interferon, the cells are less able to fend off the cancer, according to the study that will be published in the May issue of Public Library of Science-Medicine.

These results help explain a decade of research showing that people with cancer often have dysfunctional immune systems. Until now, researchers could tell that the immune system wasn't working properly but didn't know which genes or pathways were involved in that failure. Finding the disruption in the cancer cells' interferon response could help in the development of vaccines to treat cancers.

"We think this is a dominant way that immune dysfunction occurs in people with cancer," said senior author Peter Lee, MD, associate professor of medicine.

Lee was interested in melanoma rather than other forms of cancer in part because of the deadly nature of the disease, which will kill about one in six of the 47,700 people it is expected to strike this year. Unless melanoma is caught early and removed, there is no effective treatment, although research groups have been testing vaccine therapies for the disease. However, Lee worried that unless researchers better understood immune dysfunctions in those people, the vaccines would have a low probability of success. "If you don't address the underlying immune defects, then vaccines won't do any good," Lee said.

The group started by separating out the four major types of immune cells from people with melanoma and from healthy people. These cells were B cells, two types of T cells and NK, or natural killer, cells. Then, postdoctoral scholar Rebecca Critchley-Thorne, PhD, lead author of the paper, looked in the immune cells of healthy people vs. those with melanoma to see if they had the same levels of activation of roughly 20,000 genes.

She found that the B cells and both types of T cells in people with melanoma showed activity levels that differed from healthy people in only 25 of those genes. Seventeen of those 25 were normally turned on in response to interferon.

"Interferon normally acts as a critical signal in activating immune cells," said Critchley-Thorne. Without the ability to respond to interferon, those cells might detect the cancer but won't activate properly.

This type of experiment only shows that certain genes are turned on at different levels in people with melanoma. It doesn't prove that the cells behave differently than the immune cells of normal people. To verify that the interferon signaling was defective in people with melanoma, Critchley-Thorne isolated those cells and exposed them to interferon.

As predicted, immune cells from people with melanoma also failed to respond normally to the immune activation signal. However, she found that if she left the cells in the presence of a high dose of interferon for much longer than would normally be required, those cells did begin responding.

Lee said the finding explains why a common melanoma treatment, in which some doctors have treated patients with prolonged exposure to interferon, sometimes helps. "Doctors knew it worked in some people but didn't know why," Lee said. This data suggests that treatment works by overcoming the immune system's inability to react properly to interferon.

If Lee's suspicion turns out to be true, doctors may be able to screen melanoma patients for interferon response and provide prolonged interferon treatment for only those patients whose immune cells have defects in that pathway. That means patients who wouldn't benefit from the treatment could avoid suffering through interferon's flu-like side effects.

Amy Adams | EurekAlert!
Further information:
http://www.stanford.edu

More articles from Health and Medicine:

nachricht How cancer metastasis happens: Researchers reveal a key mechanism
19.01.2018 | Weill Cornell Medicine

nachricht Researchers identify new way to unmask melanoma cells to the immune system
17.01.2018 | Duke University Medical Center

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: Artificial agent designs quantum experiments

On the way to an intelligent laboratory, physicists from Innsbruck and Vienna present an artificial agent that autonomously designs quantum experiments. In initial experiments, the system has independently (re)discovered experimental techniques that are nowadays standard in modern quantum optical laboratories. This shows how machines could play a more creative role in research in the future.

We carry smartphones in our pockets, the streets are dotted with semi-autonomous cars, but in the research laboratory experiments are still being designed by...

Im Focus: Scientists decipher key principle behind reaction of metalloenzymes

So-called pre-distorted states accelerate photochemical reactions too

What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...

Im Focus: The first precise measurement of a single molecule's effective charge

For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.

Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...

Im Focus: Paradigm shift in Paris: Encouraging an holistic view of laser machining

At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.

No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...

Im Focus: Room-temperature multiferroic thin films and their properties

Scientists at Tokyo Institute of Technology (Tokyo Tech) and Tohoku University have developed high-quality GFO epitaxial films and systematically investigated their ferroelectric and ferromagnetic properties. They also demonstrated the room-temperature magnetocapacitance effects of these GFO thin films.

Multiferroic materials show magnetically driven ferroelectricity. They are attracting increasing attention because of their fascinating properties such as...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

10th International Symposium: “Advanced Battery Power – Kraftwerk Batterie” Münster, 10-11 April 2018

08.01.2018 | Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

 
Latest News

The world's most powerful acoustic tractor beam could pave the way for levitating humans

22.01.2018 | Power and Electrical Engineering

Siberian scientists learned how to reduce harmful emissions from HPPs

22.01.2018 | Power and Electrical Engineering

Combination of Resistance Genes Offers Better Protection for Wheat against Powdery Mildew

22.01.2018 | Agricultural and Forestry Science

VideoLinks
B2B-VideoLinks
More VideoLinks >>>