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Customizable and number‐tunable enzyme delivery nanocarriers will be useful in tumor therapy. Herein, a phage vehicle, T4‐Lox‐DNA‐Fe (TLDF), which adeptly modulates enzyme numbers using phage display technology to remodel the tumor microenvironment (TME) is presented. Regarding the demand for lactic acid in tumors, each phage is engineered to display 720 lactate oxidase (Lox), contributing to the depletion of lactic acid to restructure the tumor's energy metabolism. The phage vehicle incorporated dextran iron (Fe) with Fenton reaction capabilities. H2O2 is generated through the Lox catalytic reaction, amplifying the H2O2 supply for dextran iron‐based chemodynamic therapy (CDT). Drawing inspiration from the erythropoietin (EPO) biosynthetic process, an EPO enhancer is constructed to impart the EPO‐Keap1 plasmid (DNA) with tumor hypoxia‐activated functionality, disrupting the redox homeostasis of the TME. Lox consumes local oxygen, and positive feedback between the Lox and the plasmid promotes the expression of kelch ECH Associated Protein 1 (Keap1). Consequently, the downregulation of the antioxidant transcription factor Nrf2, in synergy with CDT, amplifies the oxidative killing effect, leading to tumor suppression of up to 78%. This study seamlessly integrates adaptable T4 phage vehicles with bio‐intelligent plasmids, presenting a promising approach for tumor therapy. [ABSTRACT FROM AUTHOR]

The construction of a novel nanocarrier that can break the redox balance in tumor cell is a promising anti‐tumor strategy. Herein, a tumor microenvironment (TME)‐responsive nanocarrier VC@Lipo is rationally designed by embedding ultrasmall VOx nanozyme and photosensitizer chlorin e6 (Ce6) into liposomes. The size of VC@Lipo nanocarrier is ≈35 nm and can be degraded in the weakly acidic environment of TME. The VOx nanozyme exhibits peroxidase‐like activity and generates highly toxic hydroxyl radical ∙OH through Fenton‐like reaction and 1O2 in the presence of H2O2 independent of light, and more 1O2 can be generated by the photodynamic effect of Ce6. In addition, the VOx nanozyme can effectively deplete intracellular overexpressed glutathione (GSH) through redox reactions. In vivo experiments demonstrate that the nanocarrier shows excellent biocompatibility, presents the largest enrichment at the tumor site after 6 h of intravenous injection into mice with the highest tumor inhibition rate of 54.18% after laser irradiation. Compared with the single treatment mode, VC@Lipo shows the best synergistic effect of chemodynamic‐photodynamic therapy. This work provides a new paradigm for nanocatalytic therapy of cancer and is expected to provide new ideas for precision medicine in cancer. [ABSTRACT FROM AUTHOR]

Multifunctional nanoprobes that can be applied for real‐time monitoring or precision treatment of tumors have received wide interest among researchers. However, most of these nanoprobes are obtained through chemical synthesis, and thereby may contain toxic residues or harmful reagents. In this article, a nano‐bismuth‐sphere‐cluster (Bi) is synthesized via a one‐step method (after an irradiation with ultra‐violet) and is then applied in dual‐mode computed tomography/photoacoustic imaging. Bismuth potassium citrate granules, which is a common gastric drug that is highly safe and has a low price (<1 China Yuan/g), is used as the only raw material. The results show that the Bi cluster has good stability with sizes of about 25–55 nm, and a photothermal conversion efficiency as high as 39.67%. After being adsorbed onto doxorubicin, the Bi cluster can be used directly in animal experiments. Due to the effect of enhanced permeability and retention, the probe can easily enter tumor cells. Drug release can be controlled by a near‐infrared laser and the acidic environment of tumor cells, which indicates that the combined chemo‐photothermal therapy is achieved. This work presents a new dual‐mode bio‐imaging and combined chemo‐photothermal therapeutic nanoprobe that can be applied in theragnostics for tumors. [ABSTRACT FROM AUTHOR]