Association of relative neutrophilia with a distinct immunoinhibitory milieu in non-small cell lung cancer.

Abstract

e14047 Background: Elevated neutrophil-to-lymphocyte ratio (NLR) has been associated with poor prognosis in non-small cell lung cancer (NSCLC); the biological underpinnings of this observation have not been fully elucidated. We examined the relationships between peripheral neutrophil counts (PMN), NLR, circulating cytokines and angiogenic factors (CAF), and tumor microenvironment (TME) features in NSCLC. Methods: 150 patients with resectable NSCLC were enrolled in an immunoprofiling project. A panel of 43 CAFs was used to analyze preoperative plasma samples. Chemotherapy-naïve patients with CAF and a complete blood count ≤30 days preoperatively were included (n = 66; Table). For a subset, transcriptional signatures (MCP-counter, n = 50) and flow cytometry (n = 19) were used to identify TME phenotypes. Results: Increased PMNs were associated with increased pro-inflammatory CAF such as IL-1b (r = 0.392) and IL-6 (r = 0.339), as well as Th17/Tc17 associated CAF IL-17A (r = 0.320) and TNF-a (r = 0.368). Elevated NLR was inversely correlated with the lymphocyte activation marker soluble CD27 (r = -0.320, p = 0.009). This negative association was mirrored in the TME, as tumor neutrophil signatures were inversely correlated with a local IFN-g gene signature (r = -0.626, p < 0.001). Interestingly, a Th17/Tc17 peripheral signature (elevated IL-17A) was associated with an enrichment of CD8+TIM3+ cells (r = 0.623, p = 0.042) in the tumor. While this requires confirmation in a larger cohort, this correlation provides a potential rationale for targeting TIM3 in this population. Upon analysis of clinical characteristics, peripheral PMNs and NLR were higher among patients with squamous histology (PMN p = 0.009; NLR p = 0.034) and positively correlated with tumor size (PMN r = 0.344, p = 0.004; NLR r = 0.363, p = 0.003). Conclusions: A relative neutrophilia in NSCLC patients is associated with an inflammatory milieu suggestive of a Th17/Tc17 presence and decreased lymphocyte activation that is reflected within the TME. Further investigation is needed to define the role of NLR as a predictive biomarker and to identify whether neutrophils or Th17/Tc17 T cells could serve as a therapeutic target to improve immunotherapy response in NSCLC.[Table: see text]