Background: Brain metastasis was one of the factors leading to the poor long-term prognosis of patients with lung adenocarcinoma (LUAD). Methods: The expression levels of immune genes in LUAD and LUAD brain metastases tissues were analyzed in GSE161116 dataset using the GEO2R, and the levels of differential immune genes in normal lung and LUAD tissues were verified. The biological functions and signaling mechanisms of the differential immune genes were explored via Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analysis. Cox regression analysis was used to screen the prognostic factors of LUAD patients, and a risk model was constructed. The role of the model was checked in the development of LUAD via receiver operating characteristic analysis, gene set enrichment analysis, and Cox regression analysis. Results: Differentially expressed genes (DEGs) in brain metastasis were involved in the adaptive immune response, B cell differentiation, leukocyte migration, NF-kB signaling pathway, among others. The expression levels of TNFRSF11A, MS4A2, IL11, CAMP, MS4A1, and F2RL1 were independent factors affecting the poor prognosis of LUAD patients via Cox regression analysis and Akaike information criterion. In the constructed risk model, the overall survival of LUAD patients in the high-risk group was poor. The risk model was significantly related to the gender, clinical stage, T stage, lymph node metastasis, and survival status of LUAD patients. In addition, the risk model score was an independent risk factor that affected the poor prognosis of LUAD patients. TNFRSF11A, CAMP, F2RL1, IL11, MS4A1, and MS4A2 of the risk factors had diagnostic significance in LUAD brain metastasis and LUAD. The risk model participated in cytokinetic process, cell cycle, citrate cycle TCA cycle, etc. The risk model score was correlated with the levels of B cells memory, mast cells resting, macrophages M0, mast cells activated, neutrophils, eosinophils, T cells gamma delta, and immune cell markers. Conclusions: The risk model based on the LUAD brain metastasis immune factors TNFRSF11A, MS4A2, IL11, CAMP, MS4A1, and F2RL1 was related to the diagnosis, poor prognosis, and immune infiltrating cells of LUAD patients, and is expected to provide a reference for the development of treatment strategies for LUAD patients.

CircRNAs, a type of non-coding RNA widely present in eukaryotic cells, have emerged as a prominent focus in tumor research. However, the functions of most circRNAs remain largely unexplored. Known circRNAs exert their regulatory roles through various mechanisms, including acting as microRNA sponges, binding to RNA-binding proteins, and functioning as transcription factors to modulate protein translation and coding. Tumor growth is not solely driven by gene mutations but also influenced by diverse constituent cells and growth factors within the tumor microenvironment (TME). As crucial regulators within the TME, circRNAs are involved in governing tumor growth and metastasis. This review highlights the role of circRNAs in regulating angiogenesis, matrix remodeling, and immunosuppression within the TME. Additionally, we discuss current research on hypoxia-induced circRNAs production and commensal microorganisms’ impact on the TME to elucidate how circRNAs influence tumor growth while emphasizing the significance of modulating the TME.

Post‑translational modifications (PTMs) of proteins influence their functionality by altering the structure of precursor proteins. These modifications are closely linked to tumor progression through the regulation of processes such as cell proliferation, apoptosis, angiogenesis and invasion. Tumors produce large amounts of lactic acid through aerobic glycolysis. Lactic acid not only serves an important role in cell metabolism, but also serves an important role in cell communication. Lactylation, a PTM involving lactate and lysine residues as substrates, serves as an epigenetic regulator that modulates intracellular signaling, gene expression and protein function, thereby serving a crucial role in tumorigenesis and progression. The identification of lactylation provides a key breakthrough in elucidating the interaction between tumor metabolic reprogramming and epigenetic modification. The present review primarily summarizes the occurrence of lactylation, its effect on tumor progression, drug resistance, the tumor microenvironment and gut microbiota, and its potential as a therapeutic target for cancer. The aim of the present review was to provide novel strategies for potential cancer therapies.

Background: Mitochondrial fission regulator 2 (MTFR2) was involved in the progression and development of various cancers. However, the relationship between MTFR2 with lung adenocarcinoma (LUAD) had not been reported. Herein, this study analyzed the clinical significance and potential mechanisms of MTFR2 in LUAD via bioinformatics tools. Results: We found that the level of MTFR2 was increased, and correlated with sex, age, smoking history, neoplasm staging, histological subtype and TP53 mutation status in LUAD patients. Kaplan-Meier survival analysis showed LUAD patients with increased MTFR2 had a poor prognosis. In addition, univariate COX regression analysis showed neoplasm staging, T stage, distant metastasis and MTFR2 level were risk factors for the prognosis of LUAD. A total of 1127 genes were coexpressed with MTFR2, including 840 positive and 208 negative related genes. KEGG and GSEA found that MTFR2 participated in the progression of LUAD by affecting cell cycle, DNA replication, homologous recombination, p53 signaling pathway and other mechanisms. The top 10 coexpressed genes, namely CDK1, CDC20, CCNB1, PLK1, CCNA2, AURKB, CCNB2, BUB1B, MAD2L1 and BUB1 were highly expressed, and were associated with poor prognosis in LUAD. Conclusions: Consequently, we elucidated MTFR2 was a biomarker for diagnosis and poor prognosis in LUAD, and might participate in the progression of LUAD via affecting cell cycle, DNA replication, homologous recombination and p53 signaling pathway.

This study aimed to investigate the potential association between white blood cell counts and the risk of lung cancer, including its subtypes, through Mendelian randomization (MR) analysis. We conducted a two-sample MR analysis using genome-wide association study (GWAS) summary statistics for the both exposure traits (eosinophil count, neutrophil count, lymphocyte count, monocyte count, basophil count, and total white blood cell count) and outcome traits (lung cancer and its subtypes). The GWAS dataset for lung cancer included 29,266 cases (11273 lung adenocarcinoma (LUAD), 7426 lung squamous cell carcinoma (LSCC), 2664 small cell lung cancer (SCLC)) and 56,450 controls. In MR analysis, we employed methods such as Inverse variance weighted (IVW), weighted median, MR-Egger regression, MR pleiotropy residual sum and outlier. MR analysis revealed an elevated total white blood cell (WBC) count significantly increased the risk of LUAD (IVW: OR = 1.484, 95% CI = 1.219–1.749, p = 0.003). The results confirmed a causal relationship between monocyte count and LUAD (IVW: OR = 1.687, 95% CI:1.542–1.830, p < 0.001). An increased total WBC count was associated with a higher risk of LUAD. Additionally, analysis of WBC subtypes counts indicated that monocyte count plays an crucial role in the elevated risk of LUAD.

Lung cancer is one of the most common malignant tumors, characterized by high incidence and mortality rates. Non‑small cell lung cancer (NSCLC) is the predominant histological type of lung cancer. Due to the lack of effective early diagnostic methods, the majority of patients with lung cancer present with distant metastasis at the time of initial diagnosis, often rendering treatments such as surgery and pharmacotherapy ineffective. Consequently, there is an urgent need for a more in‑depth understanding of the pathogenesis of NSCLC and the identification of novel therapeutic targets to enable more precise prediction and treatment of the disease. circular RNAs (circRNAs) are specifically expressed in tissues, owing to their high stability and specificity. The dysregulation of circRNA expression has been implicated in cancer progression, where circRNAs function as microRNA sponges, RNA‑binding protein sponges, gene splicing and transcriptional regulators and protein/peptide translational modulators. These molecules may serve as potential biomarkers for cancer prognosis and predictive indicators, as well as novel therapeutic targets. The present review summarizes the biogenesis and mechanistic functions of circRNAs, outlines their potential role in the initiation and progression of NSCLC and discusses their application as therapeutic targets in cancer treatment. The present review aimed to provide new perspectives for the development of emerging diagnostic or prognostic biomarkers and potential therapeutic targets for NSCLC.