Hepatic stellate cells drive hypoxia-inducible factor (HIF)-dependent metabolic rewiring and proliferation in hepatocellular carcinoma cells

Hepatocellular carcinoma (HCC) is the most prevalent primary liver cancer in adults and represents the third most common cause of cancer-related deaths worldwide. With limited treatment options, HCC remains a major global health problem. The majority of HCC develops in a cirrhotic liver, where the tumor microenvironment (TME) is enriched in fibroblasts derived from activated hepatic stellate cells (HSCs). Cell-cell interactions in TME play an important role in metabolic reprogramming, which is increasingly recognized as a crucial driver in HCC proliferation. The tumor-promoting and metabolic effects of HSCs on HCC cells however remain incompletely characterized. Understanding how HSC-HCC interaction regulates HCC proliferation can lead to identification of novel therapeutic targets. Here, we established a Transwell co-culture model of HSCs and HCC cells to investigate how HSC-HCC interactions regulate HCC metabolism and proliferation. Using isotope tracing metabolomics, we show that co-culture with HSCs increases proliferation of HCC cells by rewiring glucose metabolism to increase glycolysis and de novo synthesis of nucleotides. Transcriptomic and immunofluorescence staining analyses revealed that HSCs upregulate hypoxia-inducible factor (HIF) signaling in HCC cells, which contributes to metabolic rewiring and HCC proliferation. We further identified H 2 O 2 as a candidate crosstalk signal that could mediate HSC-dependent activation of HIF signaling in HCC cells. Together, these findings reveal a previously overlooked modulatory role of HSC-HCC interaction in metabolism-driven HCC progression. Targeting these pathways may represent a promising strategy to improve HCC treatment.