Lidocaine potentiates thermal ablation in cholangiocarcinoma by modulating TRPV6-Driven Ca2+/PI3K/AKT/HSF-1 signaling pathway.

Sublethal heat stress during thermal ablation induces thermotolerance and tumor recurrence, limiting its efficacy in cholangiocarcinoma (CCA). Here, we reported that lidocaine, a commonly used local anesthetic, acts as a thermosensitizer by directly targeting TRPV6, an ion channel overexpressed in CCA and correlated with poor prognosis. In CCA models, lidocaine enhanced heat-induced apoptosis and suppressed proliferation. Mechanistically, it selectively inhibited TRPV6-mediated store-operated calcium entry (SOCE), disrupting the Ca2+/PI3K/AKT/HSF-1 signaling axis, suppressing HSF-1 nuclear translocation, and downregulating cytoprotective HSP70. Direct binding between lidocaine and TRPV6 was confirmed by surface plasmon resonance (SPR), cellular thermal shift assay (CETSA), and drug affinity responsive target stability (DARTS). Molecular dynamics simulations and mutagenesis identified TRP583 as the critical binding residue; its mutation abolished lidocaine-induced calcium inhibition and thermal sensitization. In vivo, lidocaine combined with ablation significantly reduced tumor growth and recurrence. Our results establish TRPV6 as a functional target of lidocaine and provide a mechanistic basis for repurposing this anesthetic as an ablation sensitizer in CCA. This strategy offers a clinically applicable approach to overcome tumor thermotolerance and enhance the efficacy of thermal ablation in cholangiocarcinoma.