Cancer cells can turn the body’s own cleanup crew against it. That is the finding of a team at Tel Aviv University’s Gray Faculty of Medical and Health Sciences, which reported in the journal Science Immunology that tumors redirect a routine immune process to help themselves grow.
Dr. Merav Cohen led the study, working with doctoral students Roi Balaban and Ori Moskowitz.
A cleanup job gone wrong
The work centered on macrophages, immune cells that remove damaged and dead cells from the body. Done in healthy tissue, that job helps keep things stable and prevents inflammation. Inside a tumor, the researchers found, the same job changes how the macrophages behave, and the change favors the cancer.
To see it happen, the team built a technology called Effero-seq, which tracks what changes in immune cells after they engulf dead cells. Macrophages that had swallowed dead cancer cells went through what the researchers call “reprogramming.” Genes linked to tumor growth switched on.
The researchers then used a melanoma model to examine the effects. Macrophages that had eaten dead cancer cells encouraged new blood vessels to form inside the tumors. Those vessels carried oxygen and nutrients in, and the tumors grew faster. The same macrophages also responded less to the signals that normally set off an anti-cancer immune attack.
Patient data
The team also looked at data from patients with uveal melanoma, a form of eye cancer. Patients whose tumors had more immune cells carrying the genetic signature identified in the study generally had lower survival rates.
Cohen said the results show how tumors shape the immune system to support their own growth. “The better we understand these mechanisms, the better equipped we will be to develop treatments that block them and restore the immune system’s ability to fight cancer,” she said.
She called the research a pointer to “a new and promising therapeutic target, one that focuses not only on the cancer cells themselves, but also on the processes that enable them to thrive.”
This is early-stage laboratory and data work, and the team has not tested any treatment. Patients should consult their doctor for medical advice.
