Background: Breast cancer ranks as the second cause of cancer-related deaths in Egypt. Numerous immunomodulatory pathways underscore the immune system's involvement in cancer prognosis. Both Dendritic cells [DCs] and T regulatory cells [Tregs] are critical components of the immune system, and alterations in their numbers may contribute to breast cancer development, potentially impairing the body's ability to produce a durable anti-tumor immune response.
The aim of the work: The study aimed to assess the absolute numbers of dendritic cells and T regulatory cells in the peripheral blood of breast cancer patients with metastasis.
Patients and Methods: A case-control that was conducted involving 30 female patients with metastatic breast cancer, and 20 healthy subjects. Quantification of dendritic cell subsets and Tregs cells was performed using the TruCount assay via flow cytometry.
Results: Total dendritic cells, conventional dendritic cells, and plasmacytoid dendritic cells were all significantly decreased in breast cancer patients than in controls [p= 0.001 for all]. Among breast cancer patients, conventional dendritic cells were considerably lower than plasmacytoid dendritic cells [p = 0.0001]. Absolute counts of CD3⁺ T cells, CD4⁺ T cells, and the percentage of CD4⁺ T cells among CD3⁺ T cells were significantly decreased in breast cancer patients compared to controls [p = 0.001, 0.001, 0.007 respectively]. CD25⁺ T cell counts did not show significant differences between breast cancer patients and controls. However, the percentage of CD25⁺ T cells among CD4⁺ T cells was significantly increased in breast cancer patients [p = 0.0001], and a significant increase in CD25⁺ T cells was found in progesterone receptor-negative cases.
Conclusion: The study revealed a decrease in both total dendritic cells and dendritic cell subsets in the peripheral blood of breast cancer patients, alongside an increase in the percentage of regulatory T cells. These findings emphasize the significance of comprehending the role of these cells in immunoregulation.