Stanford Cancer Institute

SCI Women’s Cancer Center Innovation Awardee

October 2023

Derick Okwan, MD, PhD, assistant professor of pathology, and his co-investigator Edgar Engleman, MD, professor of pathology and of medicine (immunology and rheumatology), were awarded a $50,000 SCI Women's Cancer Center Innovation Award for their proposal “Treatment of breast cancer through reversal of bacteria-induced neutrophil-mediated immunosuppression.” Okwan seeks to understand the behavior of immune cells, such as neutrophils and macrophages during chronic diseases and is particularly interested in understanding the dynamic and varied behavior of neutrophils in cancer.

Recent studies have reported the surprising discovery of bacteria within tumors. Moreover, these bacteria appear to contribute to disease progression, for example, promoting growth of tumors in mouse models of breast cancer. Interestingly, breast cancer tumors also harbor neutrophils, white blood cells that normally kill bacteria. Yet, tumors with high neutrophil levels are associated with poor clinical outcomes. Why? Some studies suggest that the bacteria within the tumor may alter the activity of the neutrophils to enable cancer growth. With the support of the SCI Women's Cancer Center Innovation Award, Okwan plans to further examine the relationship between bacteria, neutrophils, and cancer. In preliminary experiments, Okwan and Engleman found that in a mouse breast cancer model, antibiotic treatment reduced spreading of the cancer to the lung. They also found that it was possible to activate neutrophils and cause them to kill breast tumor cells in mice. Okwan will examine whether tumor bacteria alter the activity of neutrophils. He will examine gene expression in neutrophils and other tumor cells to learn how bacteria change neutrophil function. He will also examine whether neutrophil activation leads to the elimination of tumor bacteria. In the future, he hopes to examine human tissues and eventually conduct clinical trials to test whether similar interventions would be beneficial in the treatment of breast cancer.