Transarterial chemoembolization (TACE) requires the complete embolization of tumor vessels. However, after embolization, tumor hypoxia and angiogenesis increase, and copper ions (Cu2+) play a key role in the regulation of angiogenesis. Decreasing the undesirable release of Cu2+ into serum and tumor tissues is a major challenge in the use of TACE. In this study, we constructed an adhesive injectable thermosensitive hydrogel (poly(N-isopropylacrylamide-codopamine methacrylamide), PND) loaded with a small Cu chelator (SO-N) for use in synergistic tumor embolization; this agent is called PNDS. SO-N chelates Cu2+ in a highly selective manner and can effectively consume the biocopper that is involved in angiogenesis. In addition, the adhesive thermosensitive hydrogel rapidly formed a gel in situ, which further inhibited the local blood ny to the tumor and accelerated ischemic necrosis. Moreover, the ability of PNDS to efficiently chelate Cu2+ and inhibit angiogenesis was investigated in vitro. Our in vivo experiments demonstrated that PNDS can promote tumor necrosis, reduce tumor Cu2+ levels, inhibit angiogenesis and tumor metastasis, and greatly prolong rabbit survival. This study is the first to show elevated serum Cu2+ levels in liver cancer patients with TACE failure/refractoriness; PNDS provides a promising approach for improving the efficacy of TACE for liver cancer by regulating Cu homeostasis.
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