Fe(II) and Tannic Acid-Cloaked MOF as Carrier of Artemisinin for Supply of Ferrous Ions to Enhance Treatment of Triple-Negative Breast Cancer.

Suppression of tumor development by inducing ferroptosis may provide a potential remedy for triple-negative breast cancer, which is sensitive to intracellular oxidative imbalance. Recently, artemisinin (ART) and its derivatives have been investigated as potential anticancer agents for the treatment of highly aggressive cancers via the induction of ferroptosis by iron-mediated cleavage of the endoperoxide bridge. Owing to its poor water solubility and limited intracellular iron content, it is challenging for further application in antitumor therapy. Herein, we developed ferrous-supply nano-carrier for ART based on tannic acid (TA) and ferrous ion (Fe(II)) coated on the zeolitic imidazolate framework-8 (ZIF) with ART encapsulated (TA-Fe/ART@ZIF) via coordination-driven self-assembly. Drug release experiments showed that ART was not nearly released in pH 7.4, while 59% ART was released in pH 5.0 after 10 h, demonstrating the excellent pH-triggered release. Meanwhile, a high level of intracellular ROS and MDA, accompanied with decreasing GSH and GPX4, displayed a newly developed nano-drug system displayed markedly enhanced ferroptosis. Compared with monotherapy, in vitro and vivo tumor inhibition experiments demonstrated higher efficiency of tumor suppression of TA-Fe/ART@ZIF. This work provides a novel approach to enhance the potency of ferroptotic nano-medicine and new directions for TBNC therapy.