Objective <p>Liver fibrosis and hepatocellular carcinoma (HCC) are interrelated diseases with high global mortality rates and limited therapeutic options. This study aimed to develop a dual-targeting therapeutic agent against both fibrogenesis and hepatocarcinogenesis by targeting nucleophosmin (NPM1), a multifunctional nucleolar protein overexpressed in activated hepatic stellate cells (HSCs) and HCC.</p> Methods <p>A high-affinity peptide aptamer, sP10, was identified via bimolecular fluorescence complementation (BiFC) screening for its potent binding to NPM1. In vitro assays evaluated sP10’s effects on nucleocytoplasmic shuttling of NPM1 protein, TGF-β1/Smad signaling and fibrosis biomarkers (α-SMA/collagen-I synthesis) in HSCs, M2 macrophage polarization, and HCC cell functions, including NPM1 autophagic degradation, apoptosis, proliferation, migration, and invasion. The in vivo efficacy was tested in carbon tetrachloride (CCl₄)-induced liver fibrosis mouse models and HCC xenograft models. Transcriptomic analysis identified dysregulated pathways (autophagy, ferroptosis, and ubiquitin proteolysis). Liposomal nanoparticles (sP10-LNP) have been engineered to enhance their bioavailability.</p> Results <p>sP10 potently bound NPM1 (KD = 9.216 nM), disrupted its nucleocytoplasmic shuttling, and suppressed TGF-β1/Smad signaling in HSCs, thereby reducing α-SMA/Collagen-I expression and M2 macrophage polarization.In HCC cells, sP10 induces autophagic NPM1 degradation and apoptosis and inhibits proliferation, migration and invasion. In vivo, sP10 attenuated CCl₄-induced liver fibrosis and reduced tumor growth and metastasis in xenograft models. Transcriptomics revealed sP10-mediated modulation of autophagy, ferroptosis, and ubiquitin-proteolytic pathways. The results of the preliminary toxicity test indicated that sP10 did not cause significant pathological damage to the mice. sP10-LNP reduced IC₅₀ by 50% in HCC cells, enhancing their bioavailability. These findings establish sP10 as a first-in-class dual-action inhibitor of liver fibrosis and HCC, operating via an “interface blockade–autophagic degradation” mechanism of NPM1, with high translational potential.</p> Conclusions <p>sP10 demonstrated robust efficacy in preclinical models of liver fibrosis and HCC by targeting NPM1, with sP10-LNP further improving bioavailability. This study provides a novel therapeutic strategy for these interconnected diseases, warranting further clinical translation.</p>