Fig. 1

Study design flowchart. The TCGA-LIHC dataset was utilized as the training set, while the PLANET, GEO, and the Xiangya cohorts were employed as the validation sets. To identify prognostic genes associated with RFS, univariate Cox regression analysis was conducted on DDR pathway genes notably enriched in P53-mutated samples, identifying 106 candidate genes. Evaluation metrics, such as the AUC and C-index, were used to assess the performance of 173 algorithm and parameter combinations. The optimal algorithm combination was selected to generate DDR signatures with the highest predictive significance for RFS. Subsequently, the HCC patient cohort was stratified into high and low DDR groups for comparative analysis. Differences in survival probability, clinical characteristics, microenvironment scores, immune cell infiltration, drug sensitivity patterns, and response to immunotherapy were assessed between these two groups.