A new study has found that stress can negatively affect the immune system in women with breast cancer, both throughout the body and within the tumor itself.
Published on February 14 in JAMA Network Open, the study suggests that chronic stressors may contribute to cancer progression and health disparities among different racial groups.
Researchers led by Dr. Alexandra R. Harris from the National Institutes of Health studied the biological impact of stress in 121 women with breast cancer.
The study included 56 Black women and 65 white women, all recruited from two hospitals. Scientists examined their blood, breast tumors, and nearby noncancerous tissues to analyze how stress affects the body at multiple levels.
The results showed that both Black and white women reported similar levels of stress and social support. However, Black women were more likely to live in neighborhoods with lower socioeconomic conditions. The study found that women who had stronger social support experienced positive changes in their immune response.
For example, Black women who reported feeling more supported had increased levels of interleukin-5 (a molecule that helps immune responses) and higher numbers of activated natural killer cells, which can help fight cancer in healthy breast tissue.
In contrast, women who faced higher levels of stress, discrimination, or neighborhood disadvantages showed signs of greater inflammation and harmful immune system changes. These stressors were also linked to more aggressive tumor characteristics.
Black women, in particular, showed unique immune system responses to stress, including higher levels of immune suppression and increased numbers of tumor-associated immune cells, which may promote cancer growth.
Another key finding was that women who reported high stress had an increased tumor mutational burden, meaning their tumors had more genetic changes. This may make tumors harder to treat and could contribute to worse outcomes.
The study suggests that stress could play a role in cancer disparities between different racial and socioeconomic groups. The authors emphasize that understanding how stress affects cancer biology can help develop better prevention strategies and public health interventions.
Addressing social and environmental stressors, improving community support, and reducing health inequalities may help improve outcomes for women with breast cancer.
If you care about cancer risk, please read studies that exercise may stop cancer in its tracks, and vitamin D can cut cancer death risk.
For more information about cancer, please see recent studies that yogurt and high-fiber diet may cut lung cancer risk, and results showing that new cancer treatment may reawaken the immune system.
The research findings can be found in JAMA Network Open.
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