Though a small group of proteins, the family called Ras controls a large number of cellular functions, including cell growth, differentiation, and survival.
And because the protein has a hand in cellular division, mutated Ras, which can be detected in one-third of all tumors, contributes to many human cancers by allowing for the rapid growth of diseased cells.
Now Prof. Yoel Kloog of Tel Aviv University's Department of Neurobiology, along with Dr. Itamar Goldstein of TAU's Sackler Faculty of Medicine and the Sheba Medical Center and their students Helly Vernitsky and Dr. Oded Rechavi, has found that oncogenic Ras, which promotes cancer development, can also alert the immune system to the presence of cancer cells.
For the first time, the researchers have shown the transfer of oncogenic Ras in human cells from melanoma cells to T cells, which belong to a group of white blood cells that are part of the immune system. This transfer allows the immune cells to gather crucial intelligence on what they are fighting and develop the necessary cytokines, or signalling molecules, to kill the melanoma cells.
Prof. Kloog suggests that a drug that enhances the transfer of the oncogene from the tumor to the immune cells is a potential therapy to augment the anti-cancer immune response. This research has been published in the Journal of Immunology.
Finding the tipping point
Although they found that immune cells often exchange proteins among themselves, the discovery that melanoma cells transfer mutated Ras is an intriguing first. And it's this initial transfer that begins what the researchers call a positive feedback loop.
In the lab, researchers incubated T-cells from patients with human melanoma cells that had originated from tumors to track the process of handing-off various proteins. They uncovered a circuit that runs between the cancer and immune cells. Once the melanoma cells pass oncogenic Ras to the T-cells, the T-cells are activated and begin to produce cytokines, which enhances their capacity to kill cancer cells.
As these melanoma cells pass along the mutated Ras, the immune cells become increasingly active. Eventually, enough oncogenic material is transferred across the immune cells' threshold, causing the T-cells to act on the melanoma cells from which the oncogenic Ras was derived. Ultimately, this transfer tips the scales in favor of the immune cells, the researchers say.
Exploiting the information transfer
The next step is to develop a therapy that can enhance the transfer in patients with cancers linked to oncogenic Ras, says Prof. Kloog. And although their research has so far focused on melanoma, which is known to elicit the response of the immune system, he believes that this finding could be applicable to other types of cancers.
There is a constant balancing act between cancer cells and the immune system, says Dr. Goldstein. Under normal circumstances, the immune system will kill some cancerous cells on a daily basis. The disease becomes critical when the immune system can no longer keep cancer cells in check. Although there are many theories as to how cancer cells break free of this cycle, scientists are still attempting to discover why this occurs.
Prof. Kloog and Dr. Goldstein hope that this research leads to a better understanding of how the immune system fights tumors. "It's a part of the interaction between cancer and the immune system that is not well known," says Dr. Goldstein. "We are trying to gather more comprehensive data on all the proteins that are being passed around, and how this information impacts the immune system's response to cancer."
George Hunka | Source: EurekAlert!
Further information: www.aftau.org
More articles from Health and Medicine:
Molecular sensor detects early signs of multiple sclerosis, Gladstone study finds
04.12.2013 | Gladstone Institutes
New compound for slowing the aging process can lead to novel treatments for brain diseases
04.12.2013 | The Hebrew University of Jerusalem
Quantum entanglement, a perplexing phenomenon of quantum mechanics that Albert Einstein once referred to as “spooky action at a distance,” could be even spookier than Einstein perceived.
Physicists at the University of Washington and Stony Brook University in New York believe the phenomenon might be intrinsically linked with wormholes, hypothetical features of space-time that in popular science fiction can provide a much-faster-than-light shortcut from one part of the universe to another.
But here’s the catch: One couldn’t actually ...
A star is formed when a large cloud of gas and dust condenses and eventually becomes so dense that it collapses into a ball of gas, where the pressure heats the matter, creating a glowing gas ball – a star is born.
New research from the Niels Bohr Institute, among others, shows that a young, newly formed star in the Milky Way had such an explosive growth, that it was initially about 100 times brighter than it is now. The results are published in the scientific journal, Astrophysical Journal Letters.
The young ...
EPFL scientists have shown how to achieve a dramatic increase in the capacity of optical fibers; Their simple, innovative solution reduces the amount of space required between the pulses of light that transport data
Optical fibers carry data in the form of pulses of light over distances of thousands of miles at amazing speeds. They are one of the glories of modern telecommunications technology.
However, their capacity is limited, because the pulses of light need to be lined up one after the other in ...
NASA's Hurricane and Severe Storms Sentinel airborne mission known as HS3 wrapped up for the 2013 Atlantic Ocean hurricane season at the end of September, and had several highlights. HS3 will return to NASA’s Wallops Flight Facility in Wallops Island, Va., for the 2014 Atlantic hurricane season.
During the 2013 mission, two unmanned Global Hawks flew from Wallops for the first time. The mission highlights included studying the Saharan Air Layer, following the genesis of a tropical storm, finding a unique hybrid core or center circulation in a redeveloped storm, obtaining measurements on the strongest side of ...
Nanosponges that soak up a dangerous pore-forming toxin produced by MRSA (methicillin-resistant Staphylococcus aureus) could serve as a safe and effective vaccine against this toxin.
This "nanosponge vaccine" enabled the immune systems of mice to block the adverse effects of the alpha-haemolysin toxin from MRSA—both within the bloodstream and on the skin. Nanoengineers from the University of California, San Diego described the safety and efficacy of this nanosponge vaccine in the December 1 issue of ...
04.12.2013 | Health and Medicine
04.12.2013 | Materials Sciences
04.12.2013 | Ecology, The Environment and Conservation
04.12.2013 | Event News
12.11.2013 | Event News
29.10.2013 | Event News