A breast cancer patient's own immune system plays an important role in control and treatment of breast cancer, said Daniel Stover, MD, Medical Oncologist and Computational Biologist at The Ohio State University Comprehensive Cancer Center.
"We have a growing understanding of the breast tumor-specific factors that impact how many and what immune cells infiltrate breast tumors-like breast cancer estrogen-receptor status and tumor mutation burden," Stover noted. "However, we have a poor understanding of what patient factors may influence immune cells and breast cancer."
At the recent 2021 San Antonio Breast Cancer Symposium in December, Stover presented findings from his research (Abstract PD9-11: Association of body mass index and inflammatory dietary pattern with breast cancer pathologic and genomic immunophenotype in the Nurses' Health Study).
The Nurses' Health Study and the Nurses' Health Study II are among the largest prospective investigations into the risk factors for major chronic diseases in women. Starting with the original Nurses' Health Study in 1976, more than 275,000 researchers, investigators, and contributors participate in the ongoing research program.
"We found that patients who had the greatest increase in their BMI from age 18 to time of diagnosis with breast cancer had higher RNA evidence of certain immune cell types-CD4+ and CD163+ immune cells," Stover said. "These immune cell subtypes are associated with suppression of other surrounding immune cells. We did not see any consistent/significant association between inflammatory dietary potential or physical activity and specific immune cell types."
BMI Scale & Inflammatory Dietary Pattern
"In this study, we sought to evaluate whether three patient factors associated with inflammation throughout the body-body mass index, inflammatory diet, and physical activity-were associated with immune cells in and around breast cancers," he said.
Inflammatory dietary pattern is a score developed by Ohio State researcher Fred Tabung, PhD, MSPH, based on the foods an individual eats, Stover explained. "The more inflammatory foods they eat, [then] the higher the score. This score has been validated using several large cohort studies. Body mass index does have a standard scale, which is calculated using a person's height and weight. There are many factors that can influence body mass index, including muscularity, genetics, and other factors."
Methodology & Future Research
The researchers evaluated >800 participants in the Nurses' Health Study who were also diagnosed with breast cancer. "We evaluated the association of the specific immune cell type and/or RNA signatures of immune cell type in/around their breast tumors and association with body mass index, inflammatory dietary potential, and physical activity," Stover explained.
"The next step is to validate these findings in other datasets or trials; before making any definitive conclusions or next plans, we want to be sure this holds up in other settings," he noted. "This is one of the early studies looking at how patient factors may influence the immune response to breast cancer and [it] supports the need for further investigation in this area."
Amy Gallagher is a contributing writer.