Targeting LIF With Cyclovirobuxine D to Suppress Tumor Progression via LIF/p38MAPK/p62-Modulated Mitophagy in Hepatocellular Carcinoma.

Leukemia inhibitory factor (LIF) exerts an oncogenic function in several types of cancer, including hepatocellular carcinoma (HCC). However, small-molecule inhibitors of LIF haven't been established. Here, we identified that LIF was remarkably overexpressed in HCC by multi-omics approaches, indicating that inhibition of LIF would be a promising therapeutic strategy. Inhibiting LIF could suppress proliferation and metastasis by activating p38MAPK/p62-modulated mitophagy. Interestingly, we found that the natural small-molecule Cyclovirobuxine-D (CVB-D), was a new inhibitor of cytoplasmic LIF in HCC. We further validated LIF as a potential target of CVB-D through biotin-modified CVB-D-Probe utilizing mass spectrometry. Mechanistically, we showed that CVB-D could bind to LIF at Val145, thereby inducing mitophagy, accompanied by cell cycle arrest and inhibition of invasion and migration. Moreover, we demonstrated that CVB-D had a therapeutic potential by targeting LIF-modulated mitophagy in patient-derived xenograft (PDX) models, which would elucidate LIF as a druggable target and regulatory mechanisms and exploit CVB-D as the novel small-molecule inhibitor of LIF for future HCC drug discovery.