Inflammatory Pathways and Immune Microenvironment in Non-Small Cell Lung Cancer: Multi-Dimensional Analysis and Machine Learning Prediction.

Non-small cell lung cancer (NSCLC) is a highly complex malignancy involving multiple molecular pathways including inflammatory responses, immune regulation and cell cycle dysregulation. Although previous studies have indicated the important role of inflammatory factors in NSCLC pathogenesis, the causal relationship between specific inflammatory factors and NSCLC risk, as well as their interactions with the immune microenvironment, has not been comprehensively elucidated. This study systematically evaluated the causal relationship between various inflammatory factors and NSCLC risk using Mendelian randomisation (MR) methodology. Through comprehensive transcriptomic analysis, network pharmacology approaches and protein-protein interaction network construction, we revealed molecular targets and key pathways in NSCLC. Additionally, we applied machine learning models to predict NSCLC and analysed the correlation between immune cell composition and cell cycle regulatory genes in NSCLC using flow cytometry. MR analysis showed that TGFB1 and CCL11 were positively correlated with NSCLC risk (OR = 1.173, p = 0.020; OR = 1.192, p = 0.003), while CD40 and CCL4 demonstrated protective effects (OR = 0.857, p = 0.015; OR = 0.896, p = 0.049). Bioinformatic analysis identified 74 overlapping drug-disease targets enriched in multiple inflammation-related signalling pathways. Machine learning models performed well in predicting NSCLC with AUC values of 0.723-0.763. Immune cell analysis revealed significantly increased CD8+ T cells and regulatory T cells (Tregs) in NSCLC samples, while naïve B cells were decreased. Complex correlations existed between cell cycle regulatory genes and immune cell composition, with CDK2 and CDK3 negatively correlated with Tregs (R = -0.8, p = 0.014; R = -0.72, p = 0.037), while CDK5 positively correlated with Tregs (R = 0.8, p = 0.014). This study revealed genetic associations between specific inflammatory factors and NSCLC risk, elucidating the complex interactions between inflammatory pathways and the immune microenvironment in NSCLC pathogenesis.