Fig. 4

Validation of the ProstaTrend and ProstaTrend-ffpe signature in 9 publicly available PCa cohorts. A For the ProstaTrend-ffpe signature, Kaplan–Meier curves for patients with TRS > 0 (increased risk) compared to patients with TRS ≤ 0 (reduced risk) are shown. The numbers under the cohort IDs indicate the number of patients and cases with BCR. Color shades depict the 95% CI for Kaplan–Meier curves. The curves were truncated if the number of patients at risk dropped below 10 in both groups. The colored numbers above the x-axis indicate the number of patients at risk. Log-rank tests were performed to evaluate probabilities of BCR-free survival between the two groups. The numbers in the plot (above the log-rank p-values) indicate how many ProstaTrend-ffpe genes are available in the datasets. B Forest plot of the overall logHRs and corresponding 95% confidence intervals (95% CI) estimated by Cox-regression on a standardized continuous scale. Significant logHRs with a p-value < 0.05 are highlighted in green. C We generated 1000 random gene sets each for ProstaTrend and the ProstaTrend-ffpe signature, followed by Cox-regression analysis for each cohort (see “Methods”). The estimated −log10(p-value) for the random gene sets are shown as boxplots. The p-values for ProstaTrend(-ffpe) gene sets are shown as colored dots (same p-values as in B). D The x-axis depicts the combined effect size of logHRs for genes from a univariate random-effects meta-analysis approach of the ProstaTrend training cohorts. The same meta-analysis approach was performed for the 9 validation cohorts (y-axis). Genes whose logHRs from the meta-analysis of the training cohort showed no significance (FDR ≥ 0.05) are colored in gray. The logHRs of the ProstaTrend(-ffpe) genes are colored accordingly. E The dots depict the -log10(p-values) estimated from a Cox-regression model with a two-sided Wald test. Prognostic signatures that were among the top 5 (sorted by p-value) in more than 3 cohorts were highlighted by a label. The white numbers represent the rank by p-value. The dashed vertical line indicates a p-value of 0.05. F The average rank of each prognostic gene set across all cohorts from the log-rank and Cox-regression analysis