Microbiota modulate lung squamous cell carcinoma lymph node metastasis through microbiota-geneset correlation network

The tumor-resident microbiota in lung squamous cell carcinoma (LUSC) has been reported to be associated with the initiation and progression of cancer. And the gut microbiome can modulate the efficacy of immunotherapies. However, it remains to be understood whether the tumor-resident microbiome promotes lymph node (LN) metastasis, which is important for clinical decision-making and prediction of a patient's prognosis. To investigate the potential role of tumor-resident microbiota in LN metastasis, we worked on the microbiota-geneset interaction profiles to characterize the molecular pathogenesis.

RNA sequencing data and their matched clinical and genomic information were obtained from The Cancer Genome Atlas database. The matched microorganism quantification data were accessed via the cBioPortal database. The mutational signature analysis, transcriptome analysis, gene set enrichment analysis, immune infiltration, and microbiota-geneset network analysis were performed.

In this paper, we identified the tumor microbiota composition and microbial biomarkers in patients with and without LN metastases. In addition, significantly upregulated gene sets characterize the transcript profiles of patients with LN metastases, for example, Myc Targets, E2F Targets, G2M Checkpoint, Mitotic Spindle, DNA Repair, and Oxidative Phosphorylation. Finally, we found that Proteus and Bacteroides were strongly correlated with gene sets related to tumor development and energy metabolism in the networks of patients with LN metastases.

We found the associations between intratumor microbiota and transcripts. Our results shed light on the correlation network of Proteus and Bacteroides, which may serve as a novel strategy for modulating LN metastasis.