Parthenolide inhibits the progression of intrahepatic cholangiocarcinoma by promoting ferroptosis through inhibiting UBD.

OBJECTIVE

This study aimed to investigate the antitumor activity and molecular mechanism of Parthenolide (Par) against intrahepatic cholangiocarcinoma (ICC), a highly malignant liver tumor with poor prognosis, to explore potential new treatment strategies.

METHODS

Par was identified through screening an FDA compound library. In vitro assays were performed to assess its effects on ICC cell proliferation, colony formation, invasion, migration, cell cycle, and apoptosis. An in vivo nude mouse tumor model was used to evaluate tumor growth inhibition. Transcriptomic analysis, molecular docking, and cellular thermal shift assays were employed to identify key targets and pathways. Changes in ferroptosis-related markers, including iron ion levels, lipid peroxides, SOD activity, and GPX4 expression, were measured. Rescue experiments with the ferroptosis inhibitor ferrostatin-1 were conducted to validate the role of ferroptosis.

RESULTS

Par significantly inhibited ICC cell proliferation, colony formation, invasion, and migration, induced G2/M phase arrest, and promoted apoptosis in vitro; and suppressed tumor growth in vivo. Transcriptomic analysis showed upregulation of HMOX-1 and downregulation of Ubiquitin D (UBD) after Par treatment. Par was confirmed to bind to the UBD protein. Enrichment analysis indicated ferroptosis as a key pathway, with Par treatment leading to increased iron ions, lipid peroxide accumulation, reduced SOD activity, and downregulated GPX4. Ferrostatin-1 partially reversed Par-induced inhibitory effects.

CONCLUSION

This study demonstrates for the first time that Par exerts anti-ICC effects related to inhibition of UBD, thereby activating the ferroptosis pathway. These findings provide a novel potential strategy and therapeutic target for ICC treatment.