Fig. 5
Potential ligand and receptor interactions A. Bubble heatmap showing ligands and receptors of cell‒cell interactions in different disease states. The GDF signaling pathway consists of GDF15-TGFBR2 (ligand receptor). B. Bubble heatmap showing GDF15 expression of MACRO-SPP1 (SPP1 + TAMs) in different disease states. GDF15 expression in MACRO-SPP1 (SPP1 + TAMs) is increased in metastasis. C. UMAP diagram showing the expression of GDF15 in different metastasis samples. GDF15 is mainly expressed in liver metastasis samples (L2). D. The correlation between GDF15 + SPP1 + TAM infiltration and CD8 + T exhausted cell infiltration was analyzed in the gastric cancer BULK datasets. The dotted-line plot shows a positive correlation between the GDF15 + SPP1 + TAM ssGSEA score and the CD8T-C4 (exhausted CD8 + T state) ssGSEA score. E. Comparison of CD8T-C4 (exhausted CD8 + T state) ssGSEA score between high- and low-expressed groups defined by the median expression level of GDF15 + SPP1 + TAM ssGSEA score in the TCGA-STAD cohort. F. Violin plot showing exhaustion gene expression of CD8T-C4 (exhausted CD8 + T state) in different disease states. PDCD1 and CXCL13 expression in CD8T-C4 cells (exhausted CD8 + T cells) is increased in metastasis. G. Dot-line plot showing a positive correlation between GDF15 + SPP1 + TAM ssGSEA score and exhaustion gene expression of CD8T-C4 (exhausted CD8 + T state) in the Gastric Cancer BULK Datasets. Wilcoxon test: *P < 0.05; **P < 0.01; ***P < 0.001; ****P < 0.0001