Integrative bulk and single-cell transcriptomic analysis identifies a ferro-aging-related four-gene signature associated with immune remodeling in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is characterized by a profoundly immunosuppressive tumor microenvironment, which contributes to poor clinical outcomes and limited therapeutic benefit. Ferro-aging has recently emerged as a concept linking iron dysregulation and sustained lipid peroxidation with cellular senescence, but its biological boundaries and relevance to HCC remain unclear. We integrated bulk and single-cell transcriptomic data to characterize ferro-aging-related features in HCC. A four-gene ferro-aging-related prognostic signature consisting of SLC1A5, CTSB, TFRC, and GMFB was developed using the TCGA-LIHC cohort and quantified as the RiskScore. Cross-cohort expression support was assessed in GSE14520 and GSE76427. The RiskScore was exploratorily contextualized against an unsupervised conventional ferroptosis score. Immune-cell composition and inferred cell-cell communication were analyzed, and iLINCS was used for exploratory compound screening based on the SLC1A5-high malignant-cell signature. The four-gene ferro-aging-related RiskScore stratified patients into high- and low-risk groups with moderate prognostic performance. Cross-cohort analysis provided broadly consistent expression support for the selected genes. Exploratory analysis showed different prognostic and immune-association patterns between the supervised RiskScore and the unsupervised ferroptosis score, although these scores are not directly comparable. After FDR correction, high-risk tumors showed increased inhibitory immune-checkpoint expression, higher M0 macrophage proportions, and lower activated NK-cell proportions. Single-cell analysis localized SLC1A5 expression primarily to malignant cells, while CellChat inferred MIF- and SPP1-related communication between malignant and immune populations. iLINCS analysis prioritized hypothesis-generating compounds, including AKT Inhibitor IV, whose reference signatures showed negative connectivity with the SLC1A5-high malignant-cell signature. Ferro-aging-related transcriptional features were associated with prognosis and immune remodeling in HCC. The four-gene prognostic signature provides an exploratory framework for patient stratification, while the single-cell and drug-screening findings remain hypothesis-generating.