Metastatic cancer, where cancer spreads to other parts of the body, is the main reason people die from cancer.
While doctors understand how cancer cells move away from the original tumor, it’s still a mystery why some of these cells grow into new tumors and others stay quiet for years.
A new study from the Montefiore Einstein Comprehensive Cancer Center (MECCC) has found something exciting in mice: a natural immune response that stops these wandering cancer cells from forming new tumors. This important research was recently published in the journal Cell.
“Stopping metastasis is one of the biggest challenges in cancer treatment,” said Dr. Julio Aguirre-Ghiso, the lead researcher. “We believe our discovery could lead to new ways to prevent or treat cancer that spreads.”
The research focused on breast cancer cells that had spread to the lungs. These cancer cells, called disseminated cancer cells (DCCs), sometimes start forming new tumors right away. But in other cases, they stay dormant—meaning inactive—for many years and don’t cause harm.
The team discovered that special immune cells in the lungs, called alveolar macrophages, play a key role in keeping these cancer cells asleep. Alveolar macrophages normally protect the lungs by fighting off bacteria and harmful particles. But this study shows they also help stop cancer from spreading.
These immune cells send out a protein signal called TGF-β2. This signal tells the cancer cells to stay inactive, stopping them from growing into new tumors.
What’s more, the researchers think this might not be something that only happens in the lungs. Every organ in the body has its own type of immune cells, and they might be doing the same job—keeping cancer cells quiet and stopping the spread of cancer.
In experiments with mice, the researchers removed these immune cells from the lungs. When they did, more cancer cells became active, and tumors started growing. But when the immune cells were present, they helped stop cancer from spreading.
This discovery gives scientists a new way to think about cancer treatment. Instead of only trying to kill cancer cells, future treatments could focus on keeping them asleep. By learning how to boost the signals from immune cells like alveolar macrophages, doctors may be able to prevent cancer from waking up and spreading.
The researchers hope that their findings will lead to new therapies that stop metastasis before it starts. It’s an exciting step forward in the fight against cancer and offers hope for better ways to treat and prevent this deadly disease.
If you care about cancer, please read studies about a new method to treat cancer effectively, and this low-dose, four-drug combo may block cancer spread.
For more information about cancer prevention, please see recent studies about nutrient in fish that can be a poison for cancer, and results showing this daily vitamin is critical to cancer prevention.
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