Abstract 354P
Background
Immune checkpoint inhibitors (ICIs) revolutionized lung cancer (LC) treatment; yet identifying biomarkers for predicting their success remains a challenge. This study explores the predictive role of monocyte subsets and circulating myeloid-derived suppressor cells (cMDSCs), in advanced LC patients (pts) undergoing ICIs.
Methods
As part of the “ImmunoEGA” observational study at ‘Maggiore della Carità’ Hospital (Novara, IT), blood samples from 100 LC patients were analyzed before starting ICIs. Monocyte subsets (classical: CD14+CD16−, intermediate: CD14+CD16+, non-classical: CD14low/negCD16+) and cMDSCs (PMN: CD33intCD15+, M: CD14+HLRD−) were characterized by flow cytometry. Heme-oxygenase-1 (HO-1) expression was evaluated across monocyte subsets. Pts were stratified into progression disease (PD) or NO PD (stable disease/partial or complete response) based on RECIST 1.1 criteria.
Results
Intermediate monocytes emerged as a key marker, with significantly higher frequencies in PD patients compared to NO PD (mean: 32.69% vs. 21.87%; p=0.0056). At the best response, patients with SD showed increased classical (54.8% vs. 56.9%) and intermediate monocytes (19.5% vs. 21.1%), while PD patients exhibited elevated nonclassical (6.3% vs. 14.1%) and intermediate monocytes (26.3% vs. 30.9%). A positive trend in OS and PFS was associated respectively with a lower HO-1 expression on intermediate monocytes (P=0.07, HR 0.61, 95% CI 0.370–1.042) and with a lower HO-1 expression in classical monocytes (P=0.07, HR 0.73 95% CI 0.444–1.198).
Conclusions
These findings highlight intermediate monocytes and HO-1 expression as promising predictive biomarkers for ICIs, providing a foundation for personalized treatment strategies in advanced LC, aiming to enhance patient outcomes and maximize therapeutic potential.
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.