Dehydrocostus Lactone Suppresses Hepatocellular Carcinoma by Inhibiting Protein Tyrosine Kinase-7 Mediated β-Catenin Signaling.

Dehydrocostus lactone (DHL), a sesquiterpene lactone isolated from Aucklandia lappa (Radix Aucklandiae), is a bioactive compound widely used in traditional medicine for its anti-inflammatory and antitumor properties. However, its precise molecular target and pharmacological mechanisms in hepatocellular carcinoma (HCC) remain largely undefined. This study aimed to elucidate the role of protein tyrosine kinase 7 (PTK7) in HCC and to investigate the antitumor efficacy and mechanism of DHL as a PTK7-targeting compound that inhibits the β-catenin signaling pathway. The single-cell transcriptomic data and spatial transcriptomic data, together with publicly available TCGA-LIHC and GEO datasets, were integrated to determine PTK7 expression patterns and pathway associations in HCC. Cell proliferation, apoptosis, mitochondrial membrane potential, and invasion assays were performed to evaluate DHL activity. Molecular docking, cellular thermal shift assay (CETSA), drug affinity responsive target stability (DARTS) assays, and co-immunoprecipitation assays were conducted to confirm that DHL directly inhibited interaction of PTK7 and β-catenin. The in vivo antitumor efficacy of DHL was assessed in Hep3B and Huh7 xenograft models. PTK7 was highly expressed in malignant HCC cells and positively correlated with β-catenin pathway activation. DHL treatment disrupted the PTK7-β-catenin interaction, inhibited proliferation, induced mitochondrial-dependent apoptosis, and reduced invasion by downregulating matrix metalloproteinase (MMP)-2 and MMP-9. DHL also decreased phosphorylation of protein kinase B (AKT), extracellular signal-regulated kinase (ERK), and β-catenin in a dose-dependent manner. CETSA and DARTS assays confirmed the direct inhibition of PTK7 by DHL. In vivo, DHL markedly suppressed tumor growth, achieving inhibition rates of ~34%-54% in Hep3B and 28%-58% in Huh7 xenograft models. DHL exerts significant antitumor effects in HCC by directly targeting PTK7 and inhibiting β-catenin signaling. These findings identify PTK7 as a potential therapeutic target and support the development of DHL as a promising natural agent for PTK7-directed HCC therapy.