LINC02362/hsa-miR-18a-5p/FDX1 axis suppresses proliferation and drives cuproptosis and oxaliplatin sensitivity of hepatocellular carcinoma.

Cuproptosis is a novel cell death mechanism caused by copper overload, with FDX1 serving as the key regulator. LncRNAs are known to play a significant role in the aberrant regulation of gene expression in hepatocellular carcinoma (HCC). In this study, we investigated the biological role of the LINC02362/hsa-miR-18a-5p/FDX1 axis in HCC. We first explored the expression pattern, prognostic value, biological functions, drug sensitivity, and immune effect of FDX1. Using bioinformatics techniques, we then predicted several potential target lncRNAs and miRNAs. We identified a lncRNA-miRNA-FDX1 axis based on the ceRNA mechanism. In vitro experiments were conducted to validate the relationship between the lncRNA-miRNA-FDX1 axis and its biological effects in HCC. Finally, we investigated the relationship between the LINC02362/hsa-miR-18a-5p/FDX1 axis and oxaliplatin-induced cuproptosis in HCC. Our findings indicated that FDX1 expression was downregulated in HCC tissues; however, elevated FDX1 expression correlates with improved prognosis and heightened sensitivity to oxaliplatin. We confirmed that LINC02362 binds to and directly regulates the expression of miR-18a-5p, with FDX1 a target of miR-18a-5p. Experimental results suggested that upregulating LINC02362/hsa-miR-18a-5p/FDX1 axis suppressed the proliferation of HCC cells. Furthermore, LINC02362 knockdown led to a reduction in copper concentration and resistance to elesclomol-Cu. We also discovered that augmenting the LINC02362/hsa-miR-18a-5p/FDX1 axis could bolster the sensitivity of HCC to oxaliplatin through cuproptosis. This work presents the LINC02362/hsa-miR-18a-5p/FDX1 axis as a novel pathway that triggers cuproptosis and enhances the sensitivity of HCC to oxaliplatin, presenting a promising therapeutic avenue to combat oxaliplatin resistance in HCC.