Self-Immolated Nanoadjuvant for In Situ Vaccination Immunotherapy of Colorectal Cancer

Thermosensitive Resiquimod-Loaded Lipid Nanoparticles Promote the Polarization of Tumor-Associated Macrophages to Enhance Bladder Cancer Immunotherapy

Bladder cancer is a common malignant tumor of the urinary system and is associated with high morbidity, recurrence, and mortality rates. Immunotherapy with immune checkpoint inhibitors has shown great therapeutic outcomes and safety in bladder cancer. Immune checkpoint inhibitors have also been approved as first- and second-line drugs for the treatment of locally advanced or metastatic bladder cancer. However, immunotherapy has a low response and drug assistance for cancer immunotherapy, which can be ascribed to insufficient antigen presentation, tumor immunosuppressive cell accumulation, and T lymphocyte exhaustion in the tumor microenvironment. To overcome the disadvantages of immunotherapy, we prepared a resiquimod (R848)/photothermal agent (DTPA)-loaded lipid nanoparticle (R848/DTPA@DSPE-PEG NP), which has shown good photothermal conversion efficiency, biosafety, and biocompatibility. R848/DTPA@DSPE-PEG NPs with laser irradiation (635 nm) can damage MB49 cells and induce immunogenic cell death in vitro, which could trigger an immune response. Meanwhile, R848/DTPA@DSPE-PEG NPs can also promote M1-like macrophage polarization and dendritic cell maturation in vitro. Moreover, R848/DTPA@DSPE-PEG NPs with 635 nm laser irradiation can suppress subcutaneous and orthotopic bladder tumor growth and activate the immune response, which can promote dendritic cell maturation and M1-like macrophage polarization, enhance CD8+ T lymphocyte infiltration, and reduce M2-like macrophage polarization in tumors. Bioinformatics analysis found that R848/DTPA@DSPE-PEG NPs can also induce immune-related gene overexpression of immune signaling pathways. Combined R848/DTPA@DSPE-PEG NPs with PD-1 antibody can significantly enhance antitumor therapeutic effects, reprogram tumor immunosuppressive microenvironment, and prolong the survival time.

Porphyrins and Their Derivatives in Cancer Therapy: Current Advances, Mechanistic Insights, and Prospective Directions

Porphyrin and its derivatives are widely used in cancer therapy due to their strong photon absorption capabilities and moderate light stability. Due to their hydrophobic nature, porphyrins with tetrapyrrolic macrocycles ease self-aggregation in physiological conditions. Instead, exploiting the C4 symmetry structure for self-assembly is beneficial to improve the bioavailability of porphyrin and its derivatives. Herein, this Review outlines porphyrin-based nanoformulations for therapeutic applications in cancer treatment. The typical pharmaceutical application of the integrated porphyrinic structure is systematically summarized, focusing on the typical synthetic methodologies and structure-functionality relationship. Additionally, therapeutic modalities (e.g., photothermal, photodynamic, and sonodynamic) and their synergy mechanism in regulated cell death are overviewed. Special attention is given to emerging technologies in nanocatalytic therapy, therapeutic vaccines, and proteolysis-targeting chimeras, which align with the trend toward personalization and minimal invasiveness in healthcare. Finally, we discuss the challenges and limitations of porphyrinic nanoformulations and explore their future directions in the healthcare sector, aiming to bridge the gap between research and practical clinical application.

A bibliometric insight into nanomaterials in vaccine: trends, collaborations, and future avenues

Background

The emergence of nanotechnology has injected new vigor into vaccine research. Nanovaccine research has witnessed exponential growth in recent years; yet, a comprehensive analysis of related publications has been notably absent.

Objective

This study utilizes bibliometric methodologies to reveal the evolution of themes and the distribution of nanovaccine research.

Methods

Using tools such as VOSviewer, CiteSpace, Scimago Graphica, Pajek, R-bibliometrix, and R packages for the bibliometric analysis and visualization of literature retrieved from the Web of Science database.

Results

Nanovaccine research commenced in 1981. The publication volume exponentially increased, notably in 2021. Leading contributors include the United States, the Chinese Academy of Sciences, the "Vaccine", and researcher Zhao Kai. Other significant contributors comprise China, the University of California, San Diego, Veronique Preat, the Journal of Controlled Release, and the National Natural Science Foundation of China. The USA functions as a central hub for international cooperation. Financial support plays a pivotal role in driving research advancements. Key themes in highly cited articles include vaccine carrier design, cancer vaccines, nanomaterial properties, and COVID-19 vaccines. Among 7402 keywords, the principal nanocarriers include Chitosan, virus-like particles, gold nanoparticles, PLGA, and lipid nanoparticles. Nanovaccine is primarily intended to address diseases including SARS-CoV-2, cancer, influenza, and HIV. Clustering analysis of co-citation networks identifies 9 primary clusters, vividly illustrating the evolution of research themes over different periods. Co-citation bursts indicate that cancer vaccines, COVID-19 vaccines, and mRNA vaccines are pivotal areas of focus for current and future research in nanovaccines. "candidate vaccines," "protein nanoparticle," "cationic lipids," "ionizable lipids," "machine learning," "long-term storage," "personalized cancer vaccines," "neoantigens," "outer membrane vesicles," "in situ nanovaccine," and "biomimetic nanotechnologies" stand out as research interest.

Conclusions

This analysis emphasizes the increasing scholarly interest in nanovaccine research and highlights pivotal recent research themes such as cancer and COVID-19 vaccines, with lipid nanoparticle-mRNA vaccines leading novel research directions.

The future of cancer vaccines against colorectal cancer

INTRODUCTION

Colorectal cancer (CRC) is the second most lethal malignancy worldwide. Immune checkpoint inhibitors (ICIs) benefit only 15% of patients with mismatch repair-deficient/microsatellite instability (dMMR/MSI) CRC. The majority of patients are not suitable due to insufficient immune infiltration. Cancer vaccines are a potential approach for inducing tumor-specific immunity within the solid tumor microenvironment.

AREA COVERED

In this review, we have provided an overview of the current progress in CRC vaccines over the past three years and briefly depict promising directions for further exploration.

EXPERT OPINION

Cancer vaccines are certainly a promising field for the antitumor treatment against CRC. Compared to monotherapy, cancer vaccines are more appropriate as adjuvants to standard treatment, especially in combination with ICI blockade, for microsatellite stable patients. Improved vaccine construction requires neoantigens with sufficient immunogenicity, satisfactory HLA-binding affinity, and an ideal delivery platform with perfect lymph node retention and minimal off-target effects. Prophylactic vaccines that potentially prevent CRC carcinogenesis are also worth investigating. The exploration of appropriate biomarkers for cancer vaccines may benefit prognostic prediction analysis and therapeutic response prediction in patients with CRC. Although many challenges remain, CRC vaccines represent an exciting area of research that may become an effective addition to current guidelines.