Medical

Breakthrough study explains how the immune system puts cancer cells to sleep

Breakthrough study explains how the immune system puts cancer cells to sleep
New Australian research discovered a novel type of immune cell can keep malignant cancer cells from spreading
New Australian research discovered a novel type of immune cell can keep malignant cancer cells from spreading
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TRM cells (in light green) surrounding and keeping the melanoma cells (in red) in check
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TRM cells (in light green) surrounding and keeping the melanoma cells (in red) in check
New Australian research discovered a novel type of immune cell can keep malignant cancer cells from spreading
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New Australian research discovered a novel type of immune cell can keep malignant cancer cells from spreading
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An exciting new study, led by a team of Australian researchers, has uncovered how the immune system can keep cancer cells in a dormant state. It's hoped the breakthrough insight will offer new pathways for research into immunotherapy techniques that can essentially stop a tumor's growth for an indefinite period of time.

While much modern cancer research is investigating ways to destroy these deadly cells, a new study has examined a potentially different approach to battling the nasty disease. Scientists have long understood that, in some instances, malignant cancer cells can sit in stasis for prolonged periods of time without spreading or causing disease-related symptoms. This process is called the cancer-immune equilibrium, and while it is known to be mediated by the body's immune system, we do not know exactly how it works.

"What we haven't understood are the mechanisms responsible for keeping tumors under control and in this state of dormancy," says Jason Waithman, one of the authors of the new study. "All we knew was that this 'black box' of cancer control existed – and that if we could understand this process better, we could potentially learn how to exploit it in more patients, thus saving more lives."

The new research homed in on a type of immune cell called a tissue-resident memory (TRM) T cell. TRM cells were only identified around 20 years ago, and they presented as functionally different from other types of immune cells. In order to study the effect of TRM cells on cancer-immune equilibrium, a mouse melanoma model was developed alongside a new imaging technique allowing scientists to observe the movement of these immune cells in real-time.

"Using a special microscope, we could see individual melanoma cells sitting in the skin of the mouse, and could watch the T cells move through the skin, find the melanoma cells and control the growth of those cells," explains Simone Park, one of the researchers who developed the novel imaging technique for the study.

TRM cells (in light green) surrounding and keeping the melanoma cells (in red) in check
TRM cells (in light green) surrounding and keeping the melanoma cells (in red) in check

The next step was to observe what happens to the melanoma cells when the TRM cells were depleted. The results were notable, with tumor outgrowth triggered after the TRM cells were removed. The researchers concluded TRM cells to play a fundamental role in suppressing cancer progression and maintaining cancer–immune equilibrium.

Further work is necessary to better understand exactly how these TRM cells are keeping cancer cells dormant, but the researchers are confident these results are transferable to humans. Prior research has found that cancer patients with increased levels of TRM cells have demonstrated better general treatment outcomes.

"The next step in this research is to delve into the mechanism further so we can make this process happen more often," says Waithman. "We hope this research will lead to novel ways for us to maintain cancer in a dormant state and, effectively, cure people."

The new study was published in the journal Nature.

Sources: Peter Doherty Institute, Telethon Kids Institute

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4 comments
4 comments
DeeZee
It said that the cells were identified 20 years ago. That is a LONG time ago. The millions of people that died of cancer during that 20 years is awful. My mother was one of them and my best friend probably will die this year from cancer. I'm glad there is research but it seems too slow with the technology we have today. Please hurry. 20 years already.
paul314
One of the big lessons here should be that we don't have to kill all the bad cells in order to live longer. Peaceful co-existence might be the future of a lot of branches of medicine.
P51d007
There is "no money" to be made for "curing" cancer. The "money" comes from continuing to treat it. The pharma industry would dry up, so to speak, if they came out with a cure.
BrianK56
If this is the case, screenings for TRM cells should be the norm during blood test. If a low amount is found a method of multiplying needs to be devised.