Decoding hepatocellular carcinoma prognosis: a machine learning-derived methylation signature integrating transcriptomic and tumor microenvironment insights.

[BACKGROUND] Hepatocellular carcinoma (HCC) remains one of the leading causes of cancer-related mortality worldwide, largely due to its insidious onset, aggressive progression, and limited therapeutic options, resulting in poor patient prognosis. The lack of reliable prognostic biomarkers has significantly impeded precise patient stratification and personalized treatment.

[METHODS] Presently, we integrated transcriptomic, methylomic, and clinical data from The Cancer Genome Atlas and applied a systematic combination of hundreds of machine learning algorithms to develop and validate a multidimensional prognostic signature.

[RESULTS] A robust 10-gene panel of methylation-related differentially expressed genes (mrDEGs) containing DCXR, LBP, POU2AF1, SLC16A4, CALML3, MAD2L1, PPP1R14D, S100A10, SGCB, and TMEM45A was identified. This signature significantly outperformed conventional clinicopathological parameters in predicting overall survival and demonstrated consistent robustness across multiple independent validation cohorts. Further, the differential expression of these key mrDEGs was confirmed in an independent cohort of 10 paired HCC tumor and adjacent non-tumor tissues using quantitative real-time Polymerase Chain Reaction (PCR) and western blotting, corroborating the reliability and clinical relevance of our findings. Additionally, single-cell RNA sequencing and spatial transcriptomics analyses revealed that these mrDEGs are closely associated with immune cell populations, cancer-associated fibroblasts, and metabolic pathways, contributing to the regulation of the tumor microenvironment. High-risk patients exhibited an immunosuppressive microenvironment and elevated Tumor Immune Dysfunction and Exclusion scores, indicative of enhanced tumor stemness and immune evasion potential.

[CONCLUSION] This integrative multi-omics prognostic tool, combining genetic, epigenetic, and microenvironmental information, provides a more precise model for risk stratification and prognosis prediction, offering a valuable framework for individualized therapeutic decision-making and the development of novel targeted interventions, ultimately aiming to improve clinical outcomes for HCC patients.