Phenotypic Analysis of Circulating Myeloid Derived Suppressor Cells and Their Subpopulations in Egyptian Females with Breast Cancer: A Single-Centre Case-Control Study.

BACKGROUND: Myeloid-derived suppressor cells (MDSC) are immature myeloid cells with suppressive function that has been thoroughly documented in the setting of cancer. Our purpose was to evaluate levels of MDSC and their subsets in a cohort of Egyptian patients with breast cancer. METHODS: Evaluation of peripheral blood total MDSC and its subset was done using multicolor flowcytometry in 30 malignant, 10 benign breast tumor patients and 10 healthy control females. RESULTS: BC patients had higher total MDSC levels compared to controls (p= 0.01) particularly the Monocytic MDSC (M-MDSC) and abnormal MDSC subsets (p = 0.001 and p <0.001, respectively). A tumor size > 2 cm exhibited significantly higher granulocytic MDSCs (G-MDSCs) compared to tumor size < 2 cm (p= 0.02) whereas abnormal MDSCs were significantly higher in patients with a tumor size < 2 cm (p = 0.037). CONCLUSION: MDSC and its subsets can be used as a prognostic marker of tumor size as well as a potential targets for treatment in breast cancer patients.