2D-ultrathin MXene/DOXjade platform for iron chelation chemo-photothermal therapy

An increased demand for iron is a hallmark of cancer cells and is thought necessary to promote high cell proliferation, tumor progression and metastasis. This makes iron metabolism an attractive therapeutic target. Unfortunately, current iron-based therapeutic strategies often lack effectiveness and can elicit off-target toxicities. We report here a dual-therapeutic prodrug, DOXjade, that allows for iron chelation chemo-photothermal cancer therapy. This prodrug takes advantage of the clinically approved iron chelator deferasirox (ExJade®) and the topoisomerase 2 inhibitor, doxorubicin (DOX). Loading DOXjade onto ultrathin 2D Ti3C2 MXene nanosheets produces a construct, Ti3C2-PVP@DOXjade, that allows the iron chelation and chemotherapeutic functions of DOXjade to be photo-activated at the tumor sites, while potentiating a robust photothermal effect with photothermal conversion efficiencies of up to 40%. Antitumor mechanistic investigations reveal that upon activation, Ti3C2-PVP@DOXjade serves to promote apoptotic cell death and downregulate the iron depletion-induced iron transferrin receptor (TfR). A tumor pH-responsive iron chelation/photothermal/chemotherapy antitumor effect was achieved both in vitro and in vivo. The results of this study highlight what may constitute a promising iron chelation-based phototherapeutic approach to cancer therapy.