In this paper, the alpha-beta cyclodextrin dimer is designed via "click" chemistry to connect the hydrophilic and hydrophobic segments to form self-assembled noncovalently connected micelles (NCCMs) through host-guest interactions. A peptide containing the Arg-Gly-Asp (RGD) sequence was introduced to NCCMs as a target ligand to improve the cell uptake efficacy, while PEGylated technology was employed via benzoic-imine bonds to protect the ligands in normal tissues and body fluid. In addition, two fluorescent dyes were conjugated to different segments to track the formation of the micelles as well as the assemblies. It was found that the targeting property of NCCMs was switched off before reaching the tumor sites and switched on after removing the poly(ethylene glycol) (PEG) segment in the tumor sites, which was called "tumor-triggered targeting". With deshielding of the PEG segment, the drugs loaded in NCCMs could be released rapidly due to the thermoinduced phase transition. The new concept of "tumor-triggered targeting" proposed here has great potential for cancer treatment.

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Our findings reveal previously unidentified dual roles of LRP5/6 involved in the cardiomyocyte response to ischemic injury. These findings suggest new therapeutic strategies in ischemic heart disease by fine-tuning LRP5/6 and β-catenin signaling within the Wnt/β-catenin pathway.

We have synthesized a PEGylated, phenylboronic acid modified L‐DOPA pro‐antioxidant (pPAD) that can self‐assemble into nanoparticles (pPADN) for the loading of a model glucocorticoid dexamethasone (Dex) through 1,3‐diol/phenylboronic acid chemistry and hydrophobic interactions for more effective treatment of inflammation. Upon exposure to ROS, pPADN convert into the active form of L‐DOPA, and a cascade of oxidative reactions transform it into antioxidative melanin‐like materials. Concomitantly, the structural transformation of pPADN triggers the specific release of Dex, along with the acidic pH of inflammatory tissue. In a rat model of osteoarthritis, Dex‐loaded pPADN markedly mitigate synovial inflammation, suppress joint destruction and cartilage matrix degradation, with negligible in vivo toxicity. Moreover, in situ structural transformation makes pPADN suitable for noninvasive monitoring of therapeutic effects as a photoacoustic imaging contrast agent.

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How Wnt signalling including canonical and non-canonical pathways are initiated at the cell surface is not completely understood. Here we report that Wnt receptor Frizzled (Frz) and the co-receptors LRP5 and LRP6 (LRP5/6) directly interact with each other and this interaction is regulated by the LRP6 ectodomain. Importantly, through direct binding to Frz, LRP5/6 are able to prevent Frz-regulated non-canonical pathway activation and further non-canonical pathway-mediated tumour metastasis. Knockdown of endogenous LRP5/6 promotes otherwise-nonaggressive tumour cells to migrate in vitro, whereas a soluble recombinant protein of LRP6 ectodomain suppresses migration and metastasis of otherwise-aggressive tumour cells in vitro and in vivo. Furthermore, the expression level of membrane LRP5/6 correlates inversely with metastasis in mouse and human breast cancer. Our study suggests a previously unrecognized mode of receptor interaction, revealing the mechanism of LRP5/6 in inhibition of non-canonical pathway, and a possible clinical use of the LRP6 ectodomain to impede metastasis.

With the increasing recognition of the diverse roles and significance of oxidative species in the pathogenesis of many diseases, a tremendous amount of work on the development of oxidative‐species‐responsive materials has been conducted for 1) detecting oxygen metabolites or diagnosis of oxidative‐stress‐relevant diseases, 2) reducing oxidative stress in the disease sites, and/or 3) delivering therapeutic and diagnostic agents. In this review, we first discuss the distinct features and biological functions of each oxidative species. Then the selectivity and sensitivity of chemical linkers/groups to specific oxidative species and the underlying chemistry of their particular interactions are systematically elucidated. Their potential biomedical applications are also highlighted. We expect that this comprehensive review will provide more insights for the design and development of oxidative‐species‐selective materials for more effective diagnostic and therapeutic applications.