Immune responses of six-transmembrane epithelial antigen of the prostate 4 functions as a novel biomarker in gastric cancer

Figure 1 Representative images of six-transmembrane epithelial antigen of the prostate 4 expression in patients with gastric cancer. A: Low expression of six-transmembrane epithelial antigen of the prostate 4 (STEAP4); B: High expression of STEAP4.

Figure 2 Relationship between six-transmembrane epithelial antigen of the prostate 4 level and clinical stage of gastric cancer patients. STAD: Stomach adenocarcinoma; STEAP4: Six-transmembrane epithelial antigen of the prostate 4.

Figure 3 Correlation of six-transmembrane epithelial antigen of the prostate 4 expression with immune infiltration level in gastric cancer. STAD: Stomach adenocarcinoma.

Figure 4 Stromal and immune scores in relation to six-transmembrane epithelial antigen of the prostate 4 in gastric cancer. A: Tumor purity; B: Stromal score; C: Immune score; D: ESTIMATE score; E: Tumor purity was higher in the six-transmembrane epithelial antigen of the prostate 4 (STEAP4) low expression group; F-H: Stromal score, immune score and ESTIMATE score were higher in the STEAP4 high expression group. STEAP4: Six-transmembrane epithelial antigen of the prostate 4.

Figure 5 Six-transmembrane epithelial antigen of the prostate 4 expression correlates with macrophage infiltration in stomach adenocarcinoma (n = 415). A-D: Scatter plots of associations between six-transmembrane epithelial antigen of the prostate 4 and gene markers, including CD86, CSF1R of monocytes (A); CCL2, CD68, and IL10 of TAMs (B); IRF5, PTGS2 of M1 macrophages (C); and CD163, VSIG4, and MS4A4A of M2 macrophages (D). STAD: Stomach adenocarcinoma; TAM: Tumor-associated macrophage; STEAP4: Six-transmembrane epithelial antigen of the prostate 4.

Figure 6 The close relationship between six-transmembrane epithelial antigen of the prostate 4 and dendritic cell and Treg cell infiltration. Scatter plots of associations between six-transmembrane epithelial antigen of the prostate 4 and markers, including HLA-DPB1, CD1C, NRP1, and ITGAX of dendritic cells (A); and STAT5B, TGFB1 of Tregs (B). DC: Dendritic cell; Treg: Regulatory T cell; STEAP4: Six-transmembrane epithelial antigen of the prostate 4.

Figure 7 High expression of six-transmembrane epithelial antigen of the prostate 4 tends to be associated with poor prognosis in the patients of gastric cancer. A and B: Survival curves of overall survival (OS) and disease-free survival in the Gene Expression Profiling Interactive Analysis database (n = 384); C: Survival curves of OS in the tissue chip (n = 96); D-F: Survival curves of OS (D), post-progression survival (E), and first progression (F) in the Kaplan-Meier Plotter database (n = 875, n = 498, and n = 640). OS: Overall survival; DFS: Disease-free survival; PPS: Post-progression survival; FP: First progression.