Poly(ARTEMA), a novel artesunate-based polymer induces ferroptosis in breast cancer cells

Ferroptosis, a form of non-apoptotic cell death, is emerging as a promising strategy for cancer therapy. Artesunate (ART), an extract obtained from the traditional Chinese medicine Qinghaosu, has been shown to exhibit anti-cancer activity by inducing ferroptosis in cancer cells. While previous research has focused on incorporating ART monomer into drug delivery systems for enhanced cancer targeting, this study presents 2-methacryloyloxyethyl ART polymer (poly(ARTEMA)), a novel polymer synthesized from ART for the first time. Our goal was evaluation of poly(ARTEMA) anticancer potential on breast cancer cells. First, we synthesized ARTEMA using esterification followed by its polymerization using the reversible addition-fragmentation chain transfer (RAFT) polymerization method. We evaluated its mechanism of action, focusing on two key pathways: temperature-triggered singlet oxygen generation and ferrous ions (Fe²⁺) release, both of which contribute to ferroptosis. Our results demonstrate that poly(ARTEMA) selectively generates singlet oxygen and Fe²⁺ due to the endoperoxide crosslinks, leading to cell death in breast cancer cells. We also investigated the anti-cancer potential of poly(ARTEMA) on breast cancer cells with and without a ferroptosis inhibitor. The IC₅₀ values were 125 µM for the MCF-7 cancer cell line and 300 µM for the normal MCF-10 cell line, indicating enhanced toxicity toward cancer cell lines. These findings suggested that poly(ARTEMA) induces ferroptosis in cancer cells and may serve as a promising candidate for cancer therapy with minimal cytotoxicity. To the best of our knowledge, this report may be the first that successfully synthesized poly(ARTEMA) using ART, with its anticancer potential evaluation.