223P - Frequency of the number of myeloid-derived suppressor cells in patients with lung cancer according to T stage

Background

Myeloid-derived suppressor cells (MDSCs) make up a significant part of the inflammatory cellular tumor infiltrate that maintains an immunosuppressive environment, supporting local and distant tumor spread through facilitated angiogenesis and metastasis.

Methods

Fifty-four patients with locally progressed and metastatic lung cancer were included in a cross-sectional clinical observational study. The frequency of individual MDSC populations (CD14+ MDSC, CD14+ B7H4+ MDSC, CD14+ CD23+ MDSC and CD23+ B7H4+ MDSC) was examined by flow cytometry in samples of the systemic circulation of patients with lung cancer and tumor microcirculation samples. The frequency of MDSC was analyzed in relation to the T stage (T1, T2, T3, T4) according to the 8th edition of the TNM classification of lung cancer.

Results

The highest average values of CD14+ MDSCs in systemic circulation samples and in tumor microcirculation samples were detected in patients with T4 and the lowest in T1 stage patients. The highest average values of CD14+ B7H4+ MDSCs in systemic circulation samples were detected in patients with T3 and the lowest in T1 stage patients. In the tumor microcirculation samples the highest average values of CD14+ B7H4+ MDSC were detected in patients with T3 and T2 and the lowest in T1 stage patients. The highest average values of CD14+ CD23+ MDSCs in systemic circulation samples were detected in patients with T3 and the lowest in patients with T1 tumors. In tumor microcirculation samples the highest average values of CD14+ CD23+ MDSCs were detected in patients with T4 and the lowest in T1 stage patients. The highest average values of CD23+ B7H4+ MDSCs in systemic circulation samples were detected in patients with T3 and the lowest in patients with T1 tumors. In the tumor microcirculation samples the highest average values of CD23+ B7H4+ MDSCs were detected in patients with T4 and the lowest in T1 stage patients.

Conclusions

The results of our research showed that the values of the examined MDSC populations increase with the increase in tumor (T) stage both in the peripheral blood samples of patients and in the lung tumor microcirculation samples. Further research on the role, proportion and subtypes of MDSCs in lung cancer is necessary.

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.