Fig 2: Construction and verification of genetically modified GNGT1fl/+ mice. (A) Pattern plot of conditional overexpression of GNGT1 in lung tissue. (B) Flowchart for obtaining GNGT1fl/+ mice. (C) Expression level of GNGT1 mRNA in multiple organs (lung, liver, kidney, and colon) of GNGT1fl/+ and wild-type mice. (D) Morphologic structure and GNGT1 expression of different organs in GNGT1fl/+ and wild-type mice. (E-G) Expression of cell proliferation markers (E) Ki-67, (F) PCNA, (G) and apoptosis marker caspase-3 in the lungs of GNGT1fl/+ and wild-type mice. ***, P<0.001. ATG, translation initiation codon ATG; Cre, cyclization recombination enzyme; mRNA, messenger RNA; WT, wild type; H&E, hematoxylin and eosin; IHC, immunohistochemistry; PCNA, proliferating cell nuclear antigen.

Fig 3: Immune infiltration analysis in LUAD and the association with GNGT1 expression. (A) The correlation between GNGT1 gene alteration and the infiltration of different immune cells according to TIMER. (B-D) The correlation between GNGT1 expression and the infiltration of different immune cells as calculated by R software. (E) Immunohistochemical detection of common immune cell markers in LUAD with different GNGT1 expression levels, T-lymphocyte markers CD8 and CD4, neutrophil marker MPO, and B-lymphocyte marker CD20 (red arrow: immune cells; blue arrow: MPO staining of neutrophils was positive). *, 0.01lung adenocarcinoma; aDC, activated dendritic cell; DC, dendritic cells; iDC, immature dendritic cells; NK, natural killer; pDC, plasmacytoid dendritic cells; TPM, transcripts per kilobase million; H&E, hematoxylin and eosin; MPO, myeloperoxidase; TIMER, Tumor Immune Estimation Resource.

Fig 4: The function analysis of GNGT1 in LUAD. (A) Volcano map of transcriptome analysis of DEGs between the GNGT1 high and low group. (B) Analysis of the top 5 genes associated with GNGT1. (C,D) Expression of the top 5 genes associated with GNGT1 in (C) LUAD and (D) LUSC according to GNGT1 expression. (E,F) GO and KEGG enrichment analysis of GNGT1 associated with (E) upregulation and (F) downregulation in biological pathways. (G) GSEA of genes associated with GNGT1 high expression versus those associated genes with low expression. (H) Relevance of GNGT1 across 14 functional states in difference cancers of cancer in the CancerSEA database. (I,J) The correlation between GNGT1 and functional states (metastasis, inflammation, and quiescence) in LUAD. *, 0.01lung adenocarcinoma; DEGs, differentially expressed genes; LUSC, lung squamous cell carcinoma; GO, Gene Ontology; GSEA, gene set enrichment analysis; BRCA, breast cancer; GBM, gioblastoma; OV, ovarian cancer; RB, retinoblastoma; UM, uveal melanoma; EMT, epithelial-mesenchymal transition.

Fig 5: High expression of GNGT1 promoted stemness gene expression in the lung. (A) The correlation analysis between GNGT1 and the stemness genes of LUAD in TCGA. (B) RT-qPCR and (C) immunofluorescence analysis results of stemness gene expression in lung tissues of wild-type and GNGT1fl/+ mice (×400 magnification). **, 0.001lung adenocarcinoma; TCGA, The Cancer Genome Atlas; RT-qPCR, real-time quantitative polymerase chain reaction.