Abstract 1060: Circulating early myeloid derived suppressor cells as biomarkers for early detection of lung cancer

Abstract Background. Lung cancer (LC) patients, despite innovative cancer treatments such as target and immune-therapies, still have the poorest five-year survival rate. In this context the possibility of an early detection can anticipate therapeutic intervention, avoiding aggressive therapies thus prolonging disease-free and overall survival. Therefore, the identification of new circulating early biomarkers still represents a relevant clinical need. Methods. Lung cancer (LC) patients (n=63) and heavy smokers (HS) cancer free-subjects (n=52) were evaluated for the enrichment of specific subtypes of myeloid cells. Circulating early myeloid derived suppressor cells (eMDSCs) and low-density neutrophils (LDNs) were assessed by flow cytometry on peripheral blood mononuclear cells (PMBCs). Early MDSCs were defined as CD11b+CD33+CD15-CD14- cells among Lineage negative (Lin-) HLA-DR- PBMCs, whereas LDNs were defined as CD66b+CD15+ cells within the gate of CD11b+ PBMCs. Mature and immature subtypes were discriminated according to the expression of CD10. Results. Performing a sex- and smoking -matched case-control analysis in 39 LC and 39 HS subjects we were able to compare the capacity of specific myeloid population to discriminate lung cancer patients from heavy smokers. The analysis showed significantly higher values of eMDSC (OR=1. 12; 95% Confidence Interval (CI) 1. 03-1. 21), total LDN (CD66b+CD15+; OR=1. 23; 95%CI 1. 04-1. 45) and of mature CD10+ LDN (OR=1. 30; 95%CI 1. 05-1. 61). Moreover, within the overall cohort of 63 LC patients, we analyzed the distributions of the different myeloid populations according to stage (I-II vs III-IV). In this comparison, total LDN (CD66b+CD15+; Kruskal-Wallis (KW) Test p-value=0. 014), and mature CD10+ LDN (KW test p-value=0. 006) showed significant different distributions according to tumor stage, observing higher values in patients with advanced stage. On the contrary, no difference among stages was observed for the eMDSC population. Conclusions. These findings point to eMDSCs as an early marker for lung cancer detection whereas LDN could be as well associated with disease progression. Citation Format: Orazio Fortunato, Barbara Bassani, Mara Lecchi, Paolo Verderio, Ugo Pastorino, Gabriella Sozzi, Mario Paolo Colombo, Sabina Sangaletti. Circulating early myeloid derived suppressor cells as biomarkers for early detection of lung cancer abstract. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts) ; 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84 (6Suppl): Abstract nr 1060.