Fig 1.
The optimal cut-off value of the IRGPs risk-score obtained by the time-dependent ROC curve analysis.
Abbreviations: IRGPs, immune-related gene pairs; ROC, receiver operating characteristic; AUC, area under curve.
Fig 2.
Survival curves for different risk groups.
According to the optimal cut-off value, patients from different cohorts were stratified into the high- or low- risk group. Kaplan-Meier curves were used for survival analyses between different risk groups in different datasets: (A) TCGA-SKCM training dataset. (B) The GEO external validation cohort (GSE65904). (C) The TCGA-UVM external validation cohort.
Fig 3.
Forest plots of univariate and multivariate Cox regression analyses in different cohorts.
(A) TCGA-SKCM training cohort (n = 378). (B)The GEO validation cohort (n = 186). (C) The TCGA-UVM external validation cohort (n = 75). HR, hazard ratio.
Fig 4.
Survival analyses after grouping according to gene mutation status in the TCGA-SKCM dataset.
(A) BRAF-mutated patients. (B) BRAF-wild-type patients. (C) NRAS-mutated patients. (D) NRAS-wild-type patients. All groupings, according to the genotypes, had no effect on the predictive validity of the markers.
Table 1.
Prognostic IRGPs signature.
Table 2.
Summary of the results of univariate and multivariate analyses of the risk factors for the OS of patients with melanoma in the TCGA-SKCM cohort, the TCGA-UVM cohort, and the GEO cohort.
Fig 5.
The relative fraction of infiltrated immune cells in different risk groups in the TCGA dataset.
(A) Radar plot of the difference in the abundance of 22 immune cells in tumor tissue in the two risk groups. (B) Violin plot of differences in various immune cell abundances between the high- and low-risk groups. (*FDR adjusted P-value<0.05, **FDR adjusted P-value <0.01, ***FDR adjusted P-value<0.001).
Fig 6.
The KEGG pathway enrichment analysis of 52 immune-related genes.
Significantly, there are seven genes enriched in the pathway of cytokine-cytokine receptor interactions. KEGG, Kyoto Encyclopedia of Genes and Genomes.
Fig 7.
GSEA enrichment analysis of the TCGA cohort with hallmark gene sets.
According to the GSEA results, there were four significant gene sets enrichments in the high-risk group (P < 0.05, FDR < 0.25). GSEA, Gene set enrichment analysis.