Preparation of Surface Dispersed WO3/BiVO4 Heterojunction Arrays and Their Photoelectrochemical Performance for Water Splitting.

In this work, a surface dispersed heterojunction of BiVO4-nanoparticle@WO3-nanoflake was successfully prepared by hydrothermal combined with solvothermal method. We optimized the morphology of the WO3 nanoflakes and BiVO4 nanoparticles by controlling the synthesis conditions to get the uniform BiVO4 loaded on the surface of WO3 arrays. The phase composition and morphology evolution with different reaction precursors were investigated in detail. When used as photoanodes, the WO3/BiVO4 composite exhibits superior activity with photocurrent at 3.53 mA cm-2 for photoelectrochemical (PEC) water oxidation, which is twice that of pure WO3 photoanode. The superior surface dispersion structure of the BiVO4-nanoparticle@WO3-nanoflake heterojunction ensures a large effective heterojunction area and relieves the interfacial hole accumulation at the same time, which contributes to the improved photocurrents together with the stability of the WO3/BiVO4 photoanodes.

Sequentially sustained release of anticarcinogens for postsurgical chemoimmunotherapy.

Postsurgical treatment is of great importance to combat tumor recurrence and metastasis. Anti-CD47 antibodies (aCD47) can block the CD47-signal regulatory protein-alpha (CD47-SIRPα) pathway to restore immunity. Here, an in-situ gel implantation was engineered by crosslinking chitosan (CS) and pullulan (Pul) for postsurgical treatment. A highly selected chemotherapeutic, cyclopamine (Cyc), encapsulated in liposomes (Cyc-Lip) was co-loaded with aCD47 in gels for chemoimmunotherapy. Importantly, a sequential drug release kinetics can be achieved. Nanotherapeutics were confirmed to be released prior to aCD47 in a burst-release manner, which was benefit for immediately killing residual tumor cells followed by releasing tumor antigens. Meanwhile, aCD47 was released in a sustained-release manner to restore macrophage functions and exert anti-tumor immune responses. Afterwards, the efficacy of in-situ chemoimmunotherapy was confirmed on 4T1 mouse breast cancer models, which could not only efficiently augment anti-tumor effect to inhibit tumor recurrence but also establish a long-term immune memory to combat tumor metastasis.

A bio-responsive, cargo-catchable gel for postsurgical tumor treatment via ICD-based immunotherapy.

Tumor recurrence and metastasis after surgery remain challenges for tumor treatment. Strategy that can promote the immunogenicity, activate adaptative immune response and eliminate post-operative immunosuppression would be a promising way to achieve a desired clinical benefit. In this study, immunogenic cell death (ICD) priming anti-tumor adaptive immune response was executed to potentiate immune checkpoint blockade (ICB) therapy through the PD1/PDL1 pathway for postsurgical treatment. Here, we present a bio-responsive and cargo-catchable gel depot composed of pullulan and chitosan cross-linking through matrix metalloproteinase (MMP) sensitive peptide for co-delivery of anti-programmed death-ligand 1 antibody (aPDL1) and doxorubicin -encapsulated liposomes (DOX-Lip). This drug carrier showed expected ability to respond to the highly expressed MMP in postsurgical tumor microenvironment (TME). In vivo studies on 4T1 breast tumor mouse model demonstrated that the gel depot could efficiently prolong the mouse survival after tumor resection by preventing tumor recurrence and metastasis. The results suggested that ICD combining with PD1/PDL1 blockade based on the bio-responsive and cargo-catchable gel depot could facilitate the maturation of DCs and reverse the immunosuppressive environment in tumor resection area, thus amplifying the systemic anti-tumor immune response.

pH-dependent reversibly activatable cell-penetrating peptides improve the antitumor effect of artemisinin-loaded liposomes.

Artemisinin (ART) is well known as an antimalarial drug, and it can also be used to treat inflammation as well as cancer. Although many researchers have reported the antitumor activity of ART, most of these studies were investigated in vitro. In addition, ART is sparingly soluble in water, limiting its clinical relevance in drug development. Based on the data from our preliminary study, ART is not cytotoxic at low micromolar concentrations. Thus, we hypothesized that smart nanocarriers are beneficial for not only increasing the solubility of ART but also elevating the concentration of the drug at the target, thereby inducing the ideal antitumor effect. In this article, a reversibly activatable cell-penetrating peptide ((HE)10-G5-R6 or HE-R6) was introduced to modify artemisinin (ART)-loaded liposomes (ART-Lip-HE-R6) against tumors, and in vitro and in vivo performance were investigated. ART-Lip-HE-R6 exhibited sustained release under different pH conditions. The internalization and cytotoxicity of liposomes were enhanced at low pH, i.e., 6.5, after modification with HE-R6 versus nonmodified liposomes. Moreover, a longer retention time in tumors could be observed in the ART-Lip-HE-R6 group, followed by higher efficiency of tumor suppression. In conclusion, Lip-HE-R6 might be a promising delivery system for ART in cancer therapy.