Scientists Turn Cancer's Guards Into Cancer Killers

Scientists just figured out how to turn cancer's own bodyguards against it, and the results in early testing are remarkable.

Researchers at the Icahn School of Medicine at Mount Sinai developed an experimental immunotherapy that takes a completely different approach to fighting metastatic cancer. Instead of going after cancer cells themselves, the therapy targets the protective cells that shield tumors from the immune system.

Think of a tumor as a walled fortress. Cancer cells hide inside, protected by immune cells called macrophages that normally fight infection and repair damage. But inside tumors, these macrophages get reprogrammed to block immune attacks and help cancer survive and spread.

The research team, led by Dr. Jaime Mateus-Tique, created engineered immune cells called CAR T cells that specifically target these tumor macrophages. When the therapy enters the tumor, it eliminates these protective cells and releases a powerful immune-activating molecule called interleukin-12.

The results in mice with metastatic lung and ovarian cancers were striking. Many of the treated mice survived for months longer than expected, and some were completely cured.

Advanced genomic analysis showed the therapy completely reshaped the tumor environment. It removed immune-suppressing cells and drew in cancer-killing immune cells, essentially converting the fortress into a battlefield where the body's own defenses could finally work.

Why This Inspires

What makes this breakthrough particularly hopeful is its potential reach. Macrophages exist in every type of tumor, sometimes outnumbering the cancer cells themselves. The same treatment successfully worked on both lung and ovarian cancers in testing, suggesting it could work across many different cancer types.

"We've turned foe into ally," says senior author Dr. Brian Brown, Director of the Icahn Genomics Institute. The approach could help patients with cancers that don't respond to current immunotherapies.

The team emphasizes this is proof of concept, not a cure yet. Human studies are needed to determine safety and effectiveness in patients. They're currently refining the approach to maximize effectiveness while ensuring safety before potential human testing.

This research establishes an entirely new strategy for treating cancer by targeting support cells rather than cancer cells alone. For patients facing cancers that resist current treatments, that shift in thinking offers something precious: hope grounded in science.