Intratumoral pro-oxidants promote cancer immunotherapy by recruiting and reprogramming neutrophils to eliminate tumors

Nanoparticles in tumor microenvironment remodeling and cancer immunotherapy

Cancer immunotherapy and vaccine development have significantly improved the fight against cancers. Despite these advancements, challenges remain, particularly in the clinical delivery of immunomodulatory compounds. The tumor microenvironment (TME), comprising macrophages, fibroblasts, and immune cells, plays a crucial role in immune response modulation. Nanoparticles, engineered to reshape the TME, have shown promising results in enhancing immunotherapy by facilitating targeted delivery and immune modulation. These nanoparticles can suppress fibroblast activation, promote M1 macrophage polarization, aid dendritic cell maturation, and encourage T cell infiltration. Biomimetic nanoparticles further enhance immunotherapy by increasing the internalization of immunomodulatory agents in immune cells such as dendritic cells. Moreover, exosomes, whether naturally secreted by cells in the body or bioengineered, have been explored to regulate the TME and immune-related cells to affect cancer immunotherapy. Stimuli-responsive nanocarriers, activated by pH, redox, and light conditions, exhibit the potential to accelerate immunotherapy. The co-application of nanoparticles with immune checkpoint inhibitors is an emerging strategy to boost anti-tumor immunity. With their ability to induce long-term immunity, nanoarchitectures are promising structures in vaccine development. This review underscores the critical role of nanoparticles in overcoming current challenges and driving the advancement of cancer immunotherapy and TME modification.

The Multifaceted Roles of NRF2 in Cancer: Friend or Foe?

Physiological concentrations of reactive oxygen species (ROS) play vital roles in various normal cellular processes, whereas excessive ROS generation is central to disease pathogenesis. The nuclear factor erythroid 2-related factor 2 (NRF2) is a critical transcription factor that regulates the cellular antioxidant systems in response to oxidative stress by governing the expression of genes encoding antioxidant enzymes that shield cells from diverse oxidative alterations. NRF2 and its negative regulator Kelch-like ECH-associated protein 1 (KEAP1) have been the focus of numerous investigations in elucidating whether NRF2 suppresses tumor promotion or conversely exerts pro-oncogenic effects. NRF2 has been found to participate in various pathological processes, including dysregulated cell proliferation, metabolic remodeling, and resistance to apoptosis. Herein, this review article will examine the intriguing role of phase separation in activating the NRF2 transcriptional activity and explore the NRF2 dual impacts on tumor immunology, cancer stem cells, metastasis, and long non-coding RNAs (LncRNAs). Taken together, this review aims to discuss the NRF2 multifaceted roles in both cancer prevention and promotion while also addressing the advantages, disadvantages, and limitations associated with modulating NRF2 therapeutically in cancer treatment.

Overcoming anti-PD-1/PD-L1 immune checkpoint blockade resistance: the role of macrophage, neutrophils and mast cells in the tumor microenvironment

In recent years, the anti-PD-1/PD-L1 blockade has become a game changer in cancer treatment following the unprecedented response rate. Regardless of the substantial therapy efficacy across various cancer types, some patients do not still respond to these therapies, indicating that a deeper understanding of the mechanisms of anti-PD-1/PD-L1 resistance is highly important. To overcome such resistance, the tumor-induced immunosuppressive mechanisms have been focused and several suppressor cell populations in the tumor microenvironment have been identified. Among these cells, macrophages, neutrophils, and mast cells are known to play key roles in anti-PD-1/PD-L1 resistance. Hence, gaining control over these innate immune cells can open opportunities for breaking tumor resistance to immune checkpoint inhibitors. Herein, a summary of the role of macrophages, neutrophils, and mast cells in anti-PD-1/PD-L1 resistance has been described. Also, strategies to overcome their therapeutic resistance to anti-PD-1/PD-L1 have been discussed.

Transcriptomics of Canine Inflammatory Mammary Cancer Treated with Empty Cowpea Mosaic Virus Implicates Neutrophils in Anti-Tumor Immunity

Canine inflammatory mammary cancer (IMC) is a highly aggressive and lethal cancer in dogs serving as a valuable animal model for its human counterpart, inflammatory breast cancer (IBC), both lacking effective therapies. Intratumoral immunotherapy (IT-IT) with empty cowpea mosaic virus (eCPMV) nanoparticles has shown promising results, demonstrating a reduction in tumor size, longer survival rates, and improved quality of life. This study compares the transcriptomic profiles of tumor samples from female dogs with IMC receiving eCPMV IT-IT and medical therapy (MT) versus MT alone. Transcriptomic analyses, gene expression profiles, signaling pathways, and cell type profiling of immune cell populations in samples from four eCPMV-treated dogs with IMC and four dogs with IMC treated with MT were evaluated using NanoString Technologies using a canine immune-oncology panel. Comparative analyses revealed 34 differentially expressed genes between treated and untreated samples. Five genes (CXCL8, S100A9, CCL20, IL6, and PTGS2) involved in neutrophil recruitment and activation were upregulated in the treated samples, linked to the IL17-signaling pathway. Cell type profiling showed a significant increase in neutrophil populations in the tumor microenvironment after eCPMV treatment. These findings highlight the role of neutrophils in the anti-tumor response mediated by eCPMV IT-IT and suggest eCPMV as a novel therapeutic approach for IBC/IMC.