ADH1B acts as a tumor suppressor in hepatocellular carcinoma: evidence from multi-omics integration and experimental validation

Hepatocellular Carcinoma (HCC) remains a major global health challenge associated with high mortality rates, underscoring the urgent need for deeper molecular insights and more effective therapeutic strategies. Although alcohol dehydrogenase 1B (ADH1B) is primarily recognized for its role in ethanol metabolism, its expression is frequently dysregulated across various types of cancer. However, the specific role of ADH1B in the pathogenesis of HCC has not yet been fully elucidated. We integrated multi-source datasets to evaluate ADH1B expression and its clinical significance in HCC and further extended the investigation through pan-cancer analyses. Single-cell RNA sequencing (scRNA-seq) and spatial transcriptomics were performed to characterize the distribution and expression patterns of ADH1B across different cell populations within HCC tissues. The functional effects of ADH1B on HCC cells were subsequently assessed through in vitro experiments, while zebrafish xenograft models were utilized to determine its influence on tumor growth in vivo. In addition, the molecular mechanisms and signaling pathways associated with ADH1B were systematically explored. ADH1B was consistently downregulated in HCC at both the mRNA and protein levels, and decreased ADH1B expression was significantly associated with disease progression. Single-cell and spatial transcriptomic analyses further demonstrated that ADH1B expression was specifically reduced in HCC cells. Functional assays showed that ADH1B suppressed HCC cell proliferation, migration, and invasion in vitro, while also inhibiting tumor growth in vivo. In addition, ADH1B-associated genes were primarily enriched in pathways related to metabolism and cell cycle regulation. The downregulation of ADH1B in HCC may be mediated by ATF3, hsa-miR-34b-3p, and promoter hypermethylation. The novelty of the present study lies in identifying ADH1B as a potential biomarker with important functional relevance in HCC. Moreover, the tumor-suppressive effects of ADH1B in HCC appear to be closely associated with the regulation of cellular metabolism and cell cycle progression.