Analyses of the Coexpression of Lactate Metabolism- and Ferroptosis-Related Genes in Hepatocellular Carcinoma

Introduction: Lactate has been shown to protect cells against oxidative stress both in vitro and in vivo. Ferroptosis is a form of regulated cell death driven by oxidative stress, characterized by glutathione depletion and elevated lipid peroxidation. It is hypothesized that lactate may modulate the ferroptotic process in hepatocellular carcinoma (HCC) cells. Methods: In this study, the Molecular Signatures Database was leveraged to identify key differentially expressed HCC-related lactate metabolism-related genes (LMRGs) and ferroptosis-related genes (FRGs). The functions and interactions of these genes were analyzed through Cytoscape network analyses, biological process annotation, and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment. A prognostic risk model based on these genes was constructed utilizing Weighted Gene Co-expression Network Analysis (WGCNA) and Least Absolute Shrinkage and Selection Operator (LASSO) regression. The ESTIMATE and CIBERSORT algorithms were used to assess immune infiltration in individual samples. Results: Comprehensive analysis revealed that LMRGs and FRGs are co-involved in processes such as the regulation of reactive oxygen species (ROS) and antioxidant detoxification. Based on the expression profiles of these genes, HCC patients were stratified into four distinct subgroups. These subgroups exhibited significant heterogeneity in gene expression profiles, immunological characteristics, metabolic activity patterns, mutational landscapes, immune microenvironment features, and drug sensitivity levels. tRNA mitochondrial 2-thiouridylase (TRMU) was identified as a highly expressed LMRG in HCC. Knockdown of TRMU inhibited HCC cell proliferation and migration, accompanied by elevated malondialdehyde (MDA) levels and depleted glutathione (GSH) levels, indicating that TRMU silencing induces oxidative stress and facilitates ferroptosis. Conclusion: An interplay exists between lactate metabolism and ferroptosis pathways in HCC, and the constructed risk model demonstrates predictive value for patient prognosis. As a critical gene, TRMU promotes HCC progression and suppresses ferroptosis through its high expression, suggesting it serves as a potential therapeutic target for HCC treatment. Plain Language Summary: The present results highlight the crosstalk between lactate metabolism and ferroptosis pathways in HCC cells.Further studies of the regulatory interplay between these two important pathways may ultimately lead to the design of novel treatments for HCC.Moreover, the LMRG tRNA mitochondrial 2-thiouridylase (TRMU) was found to be upregulated in HCC tissue samples and cell lines. Knocking down this gene was sufficient to suppress the proliferative and migratory activity of these HCC cells while driving oxidative stress induction and ferroptotic death therein. Keywords: hepatocellular carcinoma, lactate metabolism, ferroptosis