ABSTRACT
Background: Macrophages are critical players in regulating innate and adaptive immunity in the tumor microenvironment (TME). The prognostic value of macrophages and their heterogeneous phenotypes in non-small cell lung cancer (NSCLC) is still uncertain. Methods: Surgically-resected samples of 681 NSCLC cases were stained by multiplex immunofluorescence to examine macrophage phenotypes as well as the expression levels of program death-ligand 1 (PD-L1) on them in both tumor nest and tumor stroma, including pan-macrophage (CD68+), M1 (CD68+CD163-), and M2 macrophages (CD68+CD163+). Various other immune cell markers, including CD4, CD8, CD20, CD38, CD66B, FOXP3, and CD133, were also evaluated. Machine learning algorithm by Random Forest (RF) model was utilized to screen the robust prognostic markers and construct the CD68-based immune-related risk score (IRRS) for predicting disease-free survival (DFS). Results: The expression levels of CD68 were moderately correlated with the levels of PD-L1 (P<0.001), CD133 (P<0.001), and CD8 (P<0.001). Higher levels of CD68 (OR 1.03, 95% CI: 1.01-1.05, P<0.001) as well as M1 macrophage (OR 1.04, 95% CI: 1.01-1.06, P<0.001) indicated shorter DFS. Despite without statiscial significance, intratumoral M2 macrophage (OR 1.05, 95% CI: 0.99-1.10, P=0.081) was also associated with worse DFS. IRRS incorporating three intratumoral CD68-related markers and four intrastromal markers was constructed and validated to predict recurrence (high-risk group vs. low-risk group: OR 2.52, 95% CI: 1.89-3.38, P<0.001). The IRRS model showed good accuracy [area under the curve (AUC) =0.670, 0.709, 0.695, 0.718 for 1-, 3-, 5-year, and overall DFS survival, respectively] and the predictive performance was better than the single-marker model (area under the curve 0.718 vs. 0.500-0.654). A nomogram based on clinical characteristics and IRRS for relapse prediction was then established and exhibited better performance than the tumor-node-metastasis (TNM) classification and IRRS system (C-index 0.76 vs. 0.69 vs. 0.60, 0.74 vs. 0.67 vs. 0.60, 0.81 vs. 0.74 vs. 0.60 of the entire, training, testing cohort, respectively). Conclusions: Our study suggested close interactions between CD68 and other immune markers in TME, demonstrating the prognostic value of CD68 in relapse prediction in resectable NSCLC.
ABSTRACT
BACKGROUND: Significantly rising plasma circulating C-reaction protein (CRP) concentrations are pervasive in lung cancer (LC) development, demonstrating a bidirectional relation. However, it remains uncertain whether the causation between them exists, and the degree to which the effect varies across different ethnic ancestries remains unknown. Therefore, we attempted to investigate the causal relationship between these two phenotypes. METHODS: With summary statistics of CRP-related single nucleotide polymorphisms (SNPs) identified by several large-scale genome-wide association studies (GWAS) datasets based on five ethnic ancestries coverage worldwide, we implemented bidirectional two-sample Mendelian randomization (MR) analyses. Genetic summary data of 11,348 LC cases and 15,861 controls from the International Lung Cancer Consortium (ILCCO) were applied. The inverse-variance weighted (IVW) approach was utilized as the principal analysis, supplemented by various complementary methods. RESULTS: MR study did not reveal the causal relationship shared across genetically predisposed CRP blood concentrations and LC risk (OR =1.022, 95% CI: 0.965-1.083, P=0.455) including pathological subtypes (OR =1.026, 95% CI: 0.947-1.112, P=0.534 for lung adenocarcinoma; OR =1.060, 95% CI: 0.970-1.158, P=0.201 for squamous cell lung cancer). Further analyses among East Asian, Hispanic/Latin American, European, African American/Afro-Caribbean, and South Asian populations revealed consistent null causation. Additionally, the causal effects of LC on CRP concentrations were not statically significant (OR =0.999, 95% CI: 0.977-1.021, P=0.923). CONCLUSIONS: We did not observe a bidirectional causal association between CRP blood concentrations on LC among East Asian, Hispanic/Latin American, European, African American/Afro-Caribbean, and South Asian ancestry individuals.
