Moffitt study finds vaccine may improve breast cancer treatment outcomes

TAMPA, Fla. (Mar. 18, 2025) — Moffitt Cancer Center researchers have discovered a promising new vaccine strategy for treating a specific type of breast cancer. The innovative approach targets human epidermal growth factor receptor 2-positive, estrogen receptor-negative (HER2-positive, ER-negative) breast cancer and has shown encouraging results in a recent pilot study. Published in npj Breast Cancer, the study combined the HER2-targeting dendritic cell vaccines with standard chemotherapy, demonstrating both safety and positive response rates.

The study enrolled 30 patients with stage 2 and stage 3 HER2-positive, ER-negative breast cancer who were undergoing chemotherapy before surgery to shrink the tumor. Researchers gave the HER2-directed dendritic cell vaccine before chemotherapy to determine its effects on immune response and treatment outcomes. The results showed that patients receiving the vaccine had significant immune activity, with complete tumor disappearance observed in a notable percentage of cases.

“Our findings suggest that the dendritic cell vaccine can boost the body’s immune response against tumors, potentially improving the effectiveness of chemotherapy,” said Hatem Soliman, M.D., medical oncologist in the Breast Oncology Department at Moffitt and lead author of the study. “This approach may offer a new way to enhance breast cancer treatment and patient outcomes.”

The study also found that injecting the vaccine directly into the tumor led to greater immune cell activity within the tumor environment. This could help refine future immunotherapy strategies for breast cancer and other types of cancer.

“These findings highlight the potential of immunotherapy to transform how we treat HER2-positive breast cancer,” said Brian Czerniecki, M.D., Ph.D., co-author and chair of the Breast Oncology Department at Moffitt. “By stimulating the immune system, we may be able to create more effective, long-lasting responses for patients.”

The study was supported by the National Institutes of Health (P30-CA076292) and the United States Department of Defense Breast Cancer Research Program (W81XWH-16-1-0385).

About Moffitt Cancer Center
Moffitt is dedicated to one lifesaving mission: to contribute to the prevention and cure of cancer. The Tampa-based facility is one of only 57 National Cancer Institute-designated Comprehensive Cancer Centers, a distinction that recognizes Moffitt’s scientific excellence, multidisciplinary research, and robust training and education. Moffitt’s expert nursing staff is recognized by the American Nurses Credentialing Center with Magnet^® status, its highest distinction. For more information, call 1-888-MOFFITT (1-888-663-3488), visit MOFFITT.org, and follow the momentum on Facebook, Twitter, Instagram and YouTube. 

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