Exosomal miRNA-profiling of pleural effusion in lung adenocarcinoma and tuberculosis

Abstract

BackgroundPleural effusion (PE) caused by lung cancer is prevalent, and it is difficult to differentiate it from PE caused by tuberculosis. Exosome-based liquid biopsy offers a non-invasive technique to diagnose benign and malignant PE. Exosomal miRNAs are potential diagnostic markers and play an essential role in signal transduction and biological processes in tumor development. We hypothesized that exosomal miRNA expression profiles in PE would contribute to identifying its diagnostic markers and elucidating the molecular basis of PE formation in lung cancer.MethodsThe exosomes from PE caused by lung adenocarcinoma (LUAD) and pulmonary tuberculosis were isolated and verified by transmission electron microscopy. The exosomal miRNA profiles were identified using deep sequencing and validated with quantitative real-time PCR (qRT-PCR). We performed bioinformatic analysis for differentially expressed miRNAs to explore how exosomal miRNAs regulate pleural effusion.ResultsWe identified 99 upregulated and 91 downregulated miRNAs in malignant pleural effusion (MPE) compared to tuberculous pleural effusion (TPE). Seven differentially expressed miRNAs (DEmiRNAs) were validated by qRT-PCR, out of which 5 (71.4%) were confirmed through sequencing. Gene Ontology (GO) analysis revealed that most exosomal miRNAs target genes were involved in regulating cellular processes and nitrogen compound metabolism. According to the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis, the exosomal miRNAs target genes were mainly involved in Fc gamma R-mediated phagocytosis, Rap1 signaling pathway, and breast cancer. The hub genes, including ITGAM, FOXO1, MAPK14, YWHAB, GRIN1, and PRF1, were screened through plug-in cytoHubba. The PFR1 was identified as a critical gene in MPE formation using single-cell sequencing analysis. Additionally, we hypothesized that tumor cells affected natural killer cells and promoted the generation of PE in LUAD via the exosomal hsa-miR-3120-5p-PRF1 axis.ConclusionsWe identified exosomal miRNA profiles in LUAD-MPE and TPE, which may help in the differential diagnosis of MPE and TPE. Bioinformatic analysis revealed that these miRNAs might affect PE generation through tumor immune response in LUAD. Our results provided a new theoretical basis for understanding the function of exosomal miRNAs in LUAD-MPE.

Beyond blood: Advancing the frontiers of liquid biopsy in oncology and personalized medicine

“…The ability to differentiate between malignant and benign pleural effusions is paramount in cancer diagnostics and patient management, especially in the context of lung diseases. 79,80 Pleural effusions can be a direct consequence of malignancy or other diseases such as tuberculosis. Zhang et al's research points to exosomal miRNAs in pleural effusions as reliable biomarkers for distinguishing lung adenocarcinoma from other conditions, offering a noninvasive diagnostic approach that can significantly impact clinical decisions.…”

“…Zhang et al's research points to exosomal miRNAs in pleural effusions as reliable biomarkers for distinguishing lung adenocarcinoma from other conditions, offering a noninvasive diagnostic approach that can significantly impact clinical decisions. 79 Furthermore, studies like those conducted by Vukovic et al have shown that pleural effusions can be a more sensitive medium than blood plasma for detecting mutations like EGFR T790M, known for its association with treatment resistance in NSCLC. This enhanced sensitivity could lead to better treatment strategies and monitoring of resistance, particularly crucial in settings where advanced diagnostic facilities could be limited.…”

“…The diagnostic landscape of oncology is being reshaped by the advancements in pleural effusion analysis through liquid biopsy techniques. The ability to differentiate between malignant and benign pleural effusions is paramount in cancer diagnostics and patient management, especially in the context of lung diseases 79,80 …”

“…Zhang et al. 's research points to exosomal miRNAs in pleural effusions as reliable biomarkers for distinguishing lung adenocarcinoma from other conditions, offering a noninvasive diagnostic approach that can significantly impact clinical decisions 79 …”

“…The ability to differentiate between malignant and benign pleural effusions is paramount in cancer diagnostics and patient management, especially in the context of lung diseases. 79 , 80 …”