[Correlation analysis between the numbers of G-MDSCs and M-MDSCs in peripheral blood decrease and therapeutic effect...

Objective To detect the frequencies of myeloid-derived suppressor cells (MDSCs) in the peripheral blood of patients with colorectal cancer (CRC) in an attempt to investigate the relationship between the change of MDSC frequencies and clinicopathologic characteristics of CRC patients. Methods The frequencies of granulocytic MDSCs (G-MDSCs) and monocytic MDSCs (M-MDSCs) in the peripheral blood of 82 CRC patients and 30 healthy volunteers were detected by flow cytometry. ANOVA and t-test were used to explore the relationship between the frequencies of MDSCs in the peripheral blood and the TNM stages, lymph node metastasis, tumor sites, histological grade as well as common therapeutic measures of CRC patients. Correlation analysis was performed to evaluate the correlation between the frequencies of G-MDSCs and M-MDSCs. Results Compared with the 30 healthy volunteers, the frequencies of G-MDSCs and M-MDSCs in the peripheral blood of the 82 CRC patients were statistically higher. The frequencies of G-MDSCs and M-MDSCs in the peripheral blood from TNF stage III and IV CRC patients were obviously higher than those from stage I and II patients, and CRC patients with lymph node metastasis had remarkably higher frequencies of G-MDSCs and M-MDSCs than the patients without lymph node metastasis. There were no statistical differences in the frequencies of G-MDSCs and M-MDSCs in the peripheral blood between CRC patients with different tumor sites as well as histological grades. Radical resection and effective adjuvant chemotherapy significantly decreased the frequencies of G-MDSCs and M-MDSCs in the peripheral blood of CRC patients. No statistical correlation was found between the frequencies of circulating G-MDSCs and M-MDSCs in CRC patients. Conclusion G-MDSC and M-MDSC frequencies in the peripheral blood of CRC patients significantly increased, and were closely associated with TNM stages and lymph node metastasis. Radical resection and effective adjuvant chemotherapy significantly reduced the frequencies of circulating G-MDSCs sand M-MDSCs of CRC patients.