[Changed percentage of myeloid-derived suppressor cells in the peripheral blood of prostate cancer patients and its clinical implication].

Objective: To investigate the changes in the percentage of myeloid-derived suppressor cells (MDSCs) in the peripheral blood of prostate cancer (PCa) patients and explore the correlation of MDSCs and their subsets with the prognosis of PCa.

Methods: Using flow cytometry, we determined the percentage of MDSCs and the levels of Arg-1, iNOS and PD-L1 in the peripheral blood of 32 PCa patients and 25 healthy controls, detected the distribution of CD14+ Mo-MDSC and CD15+ PMN-MDSC subsets, and analyzed the correlation between the obtained parameters and the prognosis of PCa.

Results: Compared with the healthy controls, the PCa patients showed significant increases in the percentage of MDSCs (P<0.01) and levels of Arg-1, iNOS and PD-L1 in the peripheral blood. Statistically significant differences were observed in the distribution of the CD14+ Mo-MDSC and CD15+ PMN-MDSC subsets between the two groups（60.4% vs 72.2%, 29.5% vs 18.8%） (P<0.05). The percentages of MDSCs and Mo-MDSCs were remarkably correlated with the total survival rate of the PCa patients (P=0.025 and 0.017).

Conclusions: The percentages of MDSCs and CD14+ Mo-MDSCs in the peripheral blood were correlated with the prognosis of PCa, which may provide a target or some evidence for the clinical treatment of PCa.