Researchers at the Icahn School of Medicine at Mount Sinai have uncovered how an aging immune system promotes cancer growth, thereby addressing the long-standing question of why aging is the biggest risk factor for cancer. Their study, published in Science, reveals that as the immune system ages, it triggers harmful inflammation that can drive cancer development by promoting the accumulation of pro-tumor macrophages and suppressing cancer-fighting immune cells.
Using mice models, the team found that blocking specific inflammatory pathways, particularly those involving interleukin-1α and IL-1β, could reverse this damaging process, therefore offering a potential new approach to preventing cancer in humans. Using high-dimensional analysis and bone marrow transplants, they demonstrated that an aged immune system accelerates cancer growth, even in young mice, while rejuvenating the immune system significantly reduced cancer growth in older mice. Based on these findings, the researchers have designed early-phase clinical trials using anakinra, a drug typically used for inflammatory conditions, to potentially mitigate the harmful effects of immune aging on cancer in high-risk patients.