Breast cancer cells manipulate a key nutrient to both fuel growth and disable immune defenses—a dual strategy revealed by Chinese scientists. Researchers from the Hangzhou Institute of Medicine (HIM) of the Chinese Academy of Sciences and Sun Yat-Sen University discovered that tumors exploit the amino acid arginine to rewire immune cells into cancer allies.
Researchers found that breast cancer cells pump excess arginine into the tumor microenvironment. While this nutrient typically supports immunity, cancer cells instead use it to reprogram tumor-associated macrophages—immune cells that then suppress cancer-fighting CD8+ T cells. Cutting-edge analysis showed that cancer cell-produced arginine was converted into polyamines in macrophages, driving them into a pro-tumor state. Disrupting arginine to polyamine metabolism restored immune activity and slowed tumor growth in preclinical models. The study, published in Cancer Cell on April 3, 2025, proposes combining polyamine blocking drugs with immunotherapy to break this cycle. Though focused on breast cancer, the mechanism may apply to other tumor types.
An artistic metaphor of the breast tumor battlefield: Dark, jagged cancer cells exploit swirling blue mist—symbolizing arginine metabolism twists silver macrophages into red traitors—and disable the glowing T-cell warriors’ attack. (Graphic: AI generated)