Fig 2: Correlation analysis of glucose-6-phosphate isomerase (GPI) expression and immune infiltration in lung adenocarcinoma (LUAD). (A, B) Differential distribution of immune cells in patients with high GPI expression and low GPI expression. (C–N) Correlation between the expression level of GPI and immune infiltration in lung adenocarcinoma (LUAD): (C) Th2 cells, (D) regulatory T cells, (E) gamma delta T cells, (F) NK CD56bright cells, (G) dendritic cells (DC), (H) immature DC, (I) Mast cells, (J) central memory T cells, (K) Macrophages, (L) Eosinophils, (M) effective memory T cell, (N) CD8+ T cells. *p < 0.05, **p < 0.01, ***p < 0.001, ns, no significance.

Fig 3: The expression level of glucose-6-phosphate isomerase (GPI) in different human cancers. (A) Increased or decreased GPI expression in datasets of different cancers compared with normal tissues in the Oncomine database. (B) TIMER was used to detect the expression levels of GPI in different tumors in The Cancer Genome Atlas (TCGA) database. (C) The cBioPortal OncoPrint map shows the distribution of GPI genome changes in lung adenocarcinoma (LUAD) patients. (D–J) Expression level of GPI in normal tissues and paired adjacent tissues [unmatched tissues (D) and matched tissues (E)] and the tumor tissues from patients with different clinical characteristics in TCGA [clinical stage (F), N stage (G), primary therapy outcome (H), smoking pack-years (I), and OS event (J)]. **p < 0.01, ***p < 0.001.

Fig 4: Glucose-6-phosphate isomerase (GPI) functional clustering and interaction network analysis of GPI-related genes. (A) Heatmap showing the top 50 genes in lung adenocarcinoma (LUAD) that were positively and negatively related to GPI. Red represents positively related genes and blue represents negatively related genes. (B) Gene Ontology (GO) term and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses of GPI-related genes in LUAD. (C) Venn diagram of the GPI-related genes and the survival-related and upregulated genes in LUAD. (D) GO term and KEGG pathway analyses of the GPI-related genes and LUAD survival-related genes in LUAD.

Fig 5: Correlation analysis between glucose-6-phosphate isomerase (GPI) expression and immunoinhibitors and immunostimulators. (A) Correlation between GPI and immunoinhibitors in tumors by heatmap analysis. (B) Correlation between GPI and immunostimulators in tumors by heatmap analysis. (C–E) GPI expression is negatively correlated with the immunostimulators CD40L, IL6R, and TMEM173 in lung adenocarcinoma (LUAD).