HMGB1 orchestrates tumor-osteoclast crosstalk to drive bone metastasis in hepatocellular carcinoma.

Bone metastasis in hepatocellular carcinoma (HCC) poses a significant clinical challenge, characterized by poor prognosis and severe skeletal complications. This study identifies the HMGB1/LCN2/JAK1/STAT3 axis as the central mechanism driving HCC bone metastasis through tumor-osteoclast crosstalk. High-mobility group box 1 (HMGB1) induces osteoclast activation and differentiation, promoting lipocalin-2 (LCN2) secretion by osteoclasts, which activates the JAK1/STAT3 pathway in HCC cells, forming a feedback loop that enhances osteolytic bone resorption and tumor dissemination. Integrated single-cell and bulk RNA sequencing reveal enriched osteoclast-related and pro-metastatic pathways in the tumor-bone microenvironment, while functional assays involving knockdown and overexpression demonstrate that modulating the HMGB1/LCN2/JAK1/STAT3 axis regulates osteoclast activity, tumor growth, and bone destruction in vitro and in vivo. These results suggest the HMGB1/LCN2/JAK1/STAT3 axis as a potential therapeutic target, offering a strategy to reduce skeletal damage and systemic tumor progression, thereby contributing to improved management of advanced HCC.