Role of long-chain acyl-CoA synthetases in MASH-driven hepatocellular carcinoma and ferroptosis.

Metabolic dysfunction-associated steatohepatitis-driven hepatocellular carcinoma (MASH-HCC) incidence is rapidly rising worldwide. Lipid metabolic reprogramming is a hallmark of solid tumors to satisfy cancer's high metabolic demand. However, it may confer sensitivity to ferroptosis, a cell death mode driven by iron-dependent lipid peroxidation. In this report, we describe the lipid metabolic landscape in MASH-HCC and characterize long-chain acyl-CoA synthetases (ACSLs), a family of enzymes involved in the synthesis of cellular lipids. Bulk RNA sequencing, single-cell RNA sequencing, spatial transcriptomics, and immunohistochemistry analyses of human MASH-HCC were integrated to identify differentially expressed lipid metabolism genes. Ferroptosis in vitro was assessed in human HCC cell lines. The characterization of ACSLs was also conducted at the single-cell level in a diet-induced experimental murine model of MASH-HCC. Our analysis revealed that in human MASH-HCC, ACSLs exhibit a heterogeneous expression, with ACSL4 notably enriched in tumor tissues, contrasting with ACSL5 upregulation in noncancerous MASH. We identified a unique lipid metabolic gene signature of MASH-HCC, which included genes associated with ferroptosis vulnerability. In vitro, high ACSL4 expression was associated with increased ferroptosis sensitivity in human HCC cell lines. Finally, single-cell RNA sequencing revealed elevated