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It is highly desirable to turn “cold” tumors into “hot” ones to improve the efficacy of antitumor immunotherapy. Herein, we develop the peptide-based small interfering RNA (siRNA) micelleplexes (PA7R@siPD-L1) for normalizing vascular-immune crosstalk to establish a positive feedback loop in potentiating antitumor immunotherapy. These micelleplexes are equipped with tumor-microenvironment-responsive property for precise drug delivery and release. The prepared PA7R@siPD-L1-mediated photodynamic therapy could eliminate solid tumors and trigger immunogenic cell death to generate systematic immune responses. Meanwhile, the antiangiogenic peptide A7R normalizes the tumor vasculature by converting chaotic vascular systems into matured and organized ones, thus alleviating tumor hypoxia and promoting intratumoral infiltration by immune cells. Antitumor immunogenicity would be further strengthened with the aid of siPD-L1 by muting the resistance of tumor cells against immune effector cells. This study provides a unique therapeutic strategy in turning “cold” tumors into “hot” tumors enabled by siRNA nanomaterial.

Let Cbe an abelian monoidal category. It is proved that the nilpotent category Nil(C)of Cadmits almost monoidal structure except the unit axiom. As an application, it is proved that Hom and Tensor functors exist over Nil(C)and tensor–hom adjunction remains true over the nilpotent category of the category of finite-dimensional vector spaces, which develops some recent results on this topic.

With the growing scale of networks, network attack strategies with high attack efficiency and computational efficiency are becoming more and more important. Various attack strategies with various sorting methods have been proposed. However most of them neglected the computational efficiency. Inspired by the high computational efficiency of PageRank and HITS algorithms that used in web pages network, this paper introduces those two algorithms to the network attack separately and explores the feasibility of those two new strategies. The initial experiments choose degree and BC attack as the contrast group, and compare the attack efficiency in six virtual networks. The results indicate that considering the computational efficiency and attack efficiency simultaneously, PageRank strategy has a better attack performance than other compared strategies. Initial discussions about the results are also given.

Efficient gene delivery in an integrated drug delivery system is urgent for multimodal antitumor therapy. Herein, we describe a protocol for constructing a peptide-based siRNA delivery system to achieve tumor vascular normalization and gene silencing in 4T1 cells. We highlighted four major steps, including (1) synthesis of the chimeric peptide, (2) preparation and characterization of PA7R@siRNA micelleplexes, (3) in vitrotube formation assay and transwell cell migration assay, and (4) siRNA transfection in 4T1 cells. This delivery system is expected to be used to silence gene expression, normalize tumor vasculature, and perform other treatments based on the different peptide segments.

Exosome, which is a kind of extracellular vesicles with size around 40-160 nm, plays an important role in cell-to-cell communication in multiple diseases. Especially in tumor microenvironment, exosomes are the important pathway to transit proteins, nucleic acids and small molecules between different kinds of cells. Based on these characteristics, exosomes are served as both therapeutic agents and drug delivery systems in cancer therapy. In this review, the applications of exosomes as drug delivery systems in cancer therapy were summarized and classified according to the cell source of the exosomes, including normal cells, immune cells and tumor cells. Different modifications of exosomes and drug loading methods were presented. Finally, some challenges that hindered the clinical translation of exosomes were also discussed.

Excessive ultraviolet (UV) radiation can lead to a series of skin problems. Although commercial sunscreens can protect skin from UV-induced damage to an extent, the side effects caused by such products are still worrisome. Here, inspired by the natural photoprotection effect of human hair, we extracted the multifunctional particles from human hair as sunscreens for UV protection. Both in vitroand in vivoresults indicate that hair-derived particles (HDPs) could effectively protect skin from UV radiation. Besides, HDPs retain the antioxidant capability of melanin in hair, which avoids UV-induced oxidative damage. In addition, the unique shape of HDPs can prevent them from penetrating into the skin, thus avoiding potential toxicity. Moreover, owing to their mesoporous structure, the particles can also be used as drug carriers. With the loading of octocrylene, the particles are more effective in blocking UV radiation. This study provides an ingenious tactic for the design and development of sunscreens from a natural substance.