Artesunate targets STAT3 to alleviate Hodgkin's lymphoma via JAK-STAT/PD-L1 axis

Relapsed or refractory Hodgkin lymphoma (HL) is resistant to existing chemotherapy and PD-1 inhibitors, creating an urgent need for safe and effective drugs with novel mechanisms of action. Artesunate (ART), a classic antimalarial agent, has recently demonstrated broad-spectrum antitumor activity. However, its direct targets and core molecular mechanisms in HL remain unclear. In this study, we combined HuProt™ 20 K human proteome microarray, network pharmacology, molecular docking, and in vitro functional assays to identify the key targets and signaling pathways of ART against HL. Critical functional residues were validated through site-directed mutagenesis. Proteome microarray and protein-protein interaction network analysis identified STAT3 as the core target of ART in HL. Molecular docking revealed a binding energy of -7.2 kcal/mol between ART and STAT3, with Glu638 identified as a critical interacting residue. Functional experiments confirmed that ART significantly inhibited STAT3 phosphorylation, reduced the levels of soluble PD-L1, BCL-XL, and IL-6 in the supernatant, and suppressed HL cell proliferation and migration. Notably, both the STAT3^E638A mutation and STAT3-siRNA completely abolished the antitumor effects of ART. Collectively, ART blocks the JAK-STAT/PD-L1 signaling axis by targeting Glu638 of STAT3, achieving dual effects of inhibiting tumor survival and reversing immune evasion. This work identifies STAT3 as a direct binding target of ART in HL and establishes Glu638 as a critical functional site, providing a robust theoretical and experimental foundation for repurposing ART in the treatment of relapsed or refractory HL.