[To explore the immune landscape of lung adenocarcinoma patients with draining lymph nodes based on single cell sequencing].

Objective To explore the immune landscape of patients with lung adenocarcinoma with drainage lymph nodes by single-cell sequencing technology. Methods The lung cancer single cell dataset (GSE277742) was obtained from the Gene Expression Omnibus (GEO) database of the National Center for Biotechnology Information (NCBI). The dataset included intrathoracic DLN from 18 patients with pathologically confirmed lymph node metastasis and 4 control patients without evidence of metastasis. R language was used for data quality control, dimensionality reduction clustering, cell subgroup annotation and cell communication analysis to identify key cell subsets and screen differentially expressed genes. Kaplan-Meier survival analysis was performed using the TCGA database. Results Single cell sequencing analysis showed that the proportion of CD8+ T cells in patients with draining lymph nodes was significantly higher, among which cyclin-dependent kinase 6(CDK6), cyclin D3(CCND3), CCNH, cyclin-dependent kinase inhibitor 2A/B/D(CDKN2A/B/D) and retinoblastoma transcriptional corepressor 1(RB1) were highly expressed. TCGA database analysis showed that the expression of genes related to the BIOCARTA_CELLCYCLE_PATHWAY pathway was significantly different between tumor and normal samples, and was related to survival. Conclusion Several key genes differentially expressed in the draining lymph nodes of patients with lung adenocarcinoma are screened by bioinformatics methods, which provides a new perspective for further analysis of the regulatory mechanism of the immune microenvironment of lung adenocarcinoma with draining lymph nodes.