Spatiotemporally controlled Pseudomonas exotoxin transgene system combined with multifunctional nanoparticles for breast cancer antimetastatic therapy

Promotion of triple negative breast cancer immunotherapy by combining bioactive radicals with immune checkpoint blockade

Although immunotherapy has revolutionized clinical cancer treatment, the efficacy is limited due to the lack of tumor-associated antigens (TAAs) and the presence of compensatory immune checkpoints. To overcome the deficiency, a nano-system loaded with ozone and CD47 inhibitor RRx-001 is designed and synthesized. Upon irradiation, reactive oxygen species (ROS) generated from ozone reacts with nitric oxide (NO) metabolized from RRx-001 to form reactive nitrogen species (RNS), which presents a much stronger cell-killing ability than ROS. Molecular mechanism studies further reveal that RNS induce extensive immunogenic cell death (ICD). The released TAAs promote infiltration of cytotoxic T lymphocytes, which provides the basis for immune checkpoint blockade (ICB) therapy. Meanwhile, RRx-001 carried by the nanoparticles and the produced radicals repolarize M2-type tumor-associated macrophages (TAMs) into the anti-tumor M1-type, consequently reversing the immunosuppressive tumor microenvironment (TME). In a xenograft triple-negative breast cancer (TNBC) animal model, O3-001@lipo (liposome enwrapping O3 and RRx-001) plus irradiation shows a significant anti-tumor efficacy by improving cytotoxic lymphocyte infiltration and regulating immunosuppressive TME. In summary, the O3-001@lipo nano-system triggered by irradiation potently improves the efficacy of immunotherapy by introducing strong cytotoxic RNS, which not only enriches the toolbox of ICD inducer but also provides a strategy of treatment for immune deficient tumor. STATEMENT OF SIGNIFICANCE: This study introduces a nano-system that leverages ozone and RRx-001 in the presence of X-ray irradiation to generate reactive nitrogen species, enhancing immunogenic cell death and promoting T-lymphocyte infiltration in triple-negative breast cancer, addressing a significant unmet need in the field. The scientific contribution is the development of a clinically translatable nano-system that not only induces ICD but also reshapes the tumor microenvironment, which is expected to have a profound impact on the readership in pharmaceutics, material science, and nano-bio interaction, particularly for those interested in advanced immune therapy approaches.

Drug Delivery System Targeting Cancer-Associated Fibroblast for Improving Immunotherapy

Cancer-associated fibroblasts (CAFs) are a heterogeneous population of non-malignant cells that play a crucial role in the tumor microenvironment, increasingly recognized as key contributors to cancer progression, metastasis, and treatment resistance. So, targeting CAFs has always been considered an important part of cancer immunotherapy. However, targeting CAFs to improve the efficacy of tumor therapy is currently a major challenge. Nanomaterials show their unique advantages in the whole process. At present, nanomaterials have achieved significant accomplishments in medical applications, particularly in the field of cancer-targeted therapy, showing enormous potential. It has been confirmed that nanomaterials can not only directly target CAFs, but also interact with the tumor microenvironment (TME) and immune cells to affect tumorigenesis. As for the cancer treatment, nanomaterials could enhance the therapeutic effect in many ways. Therefore, in this review, we first summarized the current understanding of the complex interactions between CAFs and TME, immune cells, and tumor cells. Next, we discussed common nanomaterials in modern medicine and their respective impacts on the TME, CAFs, and interactions with tumors. Finally, we focus on the application of nano drug delivery system targeting CAFs in cancer therapy.

An Oral H2S Responsive Cu5.4O Nanozyme Platform with Strong ROS/H2S Scavenging Capacity for the Treatment of Colitis

Inflammatory bowel disease involves excess reactive oxygen species (ROS) and hydrogen sulfide (H2S) at inflammatory sites. Nanozyme-mediated ROS and H2S scavenging therapy is promising for colitis treatment. Here, we synthesized a multiple ROS scavenging Cu5.4O nanoparticle and first explored its H2S scavenging capacity. Chitosan oligosaccharide modified with alpha-lipoic acid was coated on the nanoparticles to further enhance the H2S scavenging capacity. Furthermore, calcium alginate was coated on the surface to develop an oral nanoplatform (Cu5.4O@SAG) possessing dual-pH/H2S-responsive release characteristics. Importantly, Cu5.4O@SAG exhibited enrichment at the colonic inflammation site and relieved the inflammatory index, containing the recovery of colon length, spleen index, liver index, and body weight, as well as inflammatory cell infiltration. In vivo and in vitro experiments revealed the dual ROS and H2S scavenging capacities of the nanoplatform. Additionally, Cu5.4O@SAG regulated tight junctions, mucus layers, and gut microbiota, which was accompanied by the downregulation of inflammatory cytokines. Notably, Cu5.4O@SAG also had excellent biocompatibility. In conclusion, this oral multiple-scavenging nanozyme platform provides a new and safe paradigm for the development of nanozymes for colitis treatment.

Tofacitinib Citrate Coordination-Based Dual-Responsive/Scavenge Nanoplatform Toward Regulate Colonic Inflammatory Microenvironment for Relieving Colitis

Ulcerative colitis is an inflammation of the colon characterized by immune dysregulation and intestinal inflammation. Developing safe oral nanomedicines that suppress intestinal inflammation, while modulating colonic inflammatory microenvironment by scavenging reactive oxygen species (ROS) and hydrogen sulfide (H2S) is crucial for the effective treatment of colitis. Here, the tofacitinib citrate and copper coordination-based nanoparticle (TF-Cu nanoparticle, T-C) to dual-scavenge ROS and H2S by coordination competition is synthesized. Moreover, the coordination of T-C using computer simulation is explored. To enhance the acid stability and inflammatory targeting of T-C, it is encapsulated with hyaluronic acid-modified chitosan, along with a calcium pectinate coating (T-C@HP). Owing to the dual pH/pectinase-responsive characteristics of T-C@HP, the nanoplatform can target inflamed colonic lesions, inhibiting phosphorylated Janus kinase 1. Furthermore, T-C@HP scavenges ROS and H2S, as well as increases NADPH levels, which is investigated by combining biosensor (HyPer7 and iNap1/c) and chemical probes. T-C@HP also alleviates colitis by regulating the colonic inflammatory microenvironment through multiple processes, including the modulation of apoptosis, macrophage polarization, tight junction, mucus layer, and intestinal flora. Complemented by satisfactory anti-inflammatory and biosafety results, this nanoplatform represents a promising, effective, and safe treatment option for colitis patients.

Breast Cancer Treatment Strategies Targeting the Tumor Microenvironment: How to Convert "Cold" Tumors to "Hot" Tumors

Breast cancer characterized as "cold tumors" exhibit low levels of immune cell infiltration, which limits the efficacy of conventional immunotherapy. Recent studies have focused on strategies using nanotechnology combined with tumor microenvironment modulation to transform "cold tumors" into "hot tumors". This approach involves the use of functionalized nanoparticles that target and modify the tumor microenvironment to promote the infiltration and activation of antitumor immune cells. By delivering immune activators or blocking immunosuppressive signals, these nanoparticles activate otherwise dormant immune responses, enhancing tumor immunogenicity and the therapeutic response. These strategies not only promise to increase the response rate of breast cancer patients to existing immunotherapies but also may pave new therapeutic avenues, providing a new direction for the immunotherapy of breast cancer.

Integrin αvβ3-targeted self-assembled polypeptide nanomicelles for efficacious sonodynamic therapy against breast cancer

Sonodynamic therapy (SDT) is an advanced non-invasive cancer treatment strategy with moderate tissue penetration, less invasiveness and a reliable curative effect. However, due to the low stability, potential bio-toxicity and lack of tumor targeting capability of most sonosensitizers, the vast clinical application of SDT has been challenging and limited. Therefore, it is desirable to develop a novel approach to implement sonosensitizers to SDT for cancer treatments. In this study, an amphiphilic polypeptide was designed to effectively encapsulate rose bengal (RB) as a model sonosensitizer to form peptido-nanomicelles (REPNs). The as-fabricated REPNs demonstrated satisfactory tumor targeting and fluorescence performances, which made them superb imaging tracers in vivo. In the meantime, they generated considerable amounts of reactive oxygen species (ROS) to promote tumor cell apoptosis under ultrasound irradiation and showed excellent anti-tumor performance without obvious side effects. These engineered nanomicelles in combination with medical ultrasound may be used to achieve integrin αvβ3-targeted sonodynamic therapy against breast cancer, and it is also a promising non-invasive cancer treatment strategy for clinical translations.

The Application of Nanoparticles Targeting Cancer-Associated Fibroblasts

Cancer-associated fibroblasts (CAF) are the most abundant stromal cells in the tumor microenvironment (TME), especially in solid tumors. It has been confirmed that it can not only interact with tumor cells to promote cancer progression and metastasis, but also affect the infiltration and function of immune cells to induce chemotherapy and immunotherapy resistance. So, targeting CAF has been considered an important method in cancer treatment. The rapid development of nanotechnology provides a good perspective to improve the efficiency of targeting CAF. At present, more and more researches have focused on the application of nanoparticles (NPs) in targeting CAF. These studies explored the effects of different types of NPs on CAF and the multifunctional nanomedicines that can eliminate CAF are able to enhance the EPR effect which facilitate the anti-tumor effect of themselves. There also exist amounts of studies focusing on using NPs to inhibit the activation and function of CAF to improve the therapeutic efficacy. The application of NPs targeting CAF needs to be based on an understanding of CAF biology. Therefore, in this review, we first summarized the latest progress of CAF biology, then discussed the types of CAF-targeting NPs and the main strategies in the current. The aim is to elucidate the application of NPs in targeting CAF and provide new insights for engineering nanomedicine to enhance immune response in cancer treatment.