Engineered Apoptosis-Bioinspired Nanoparticles Initiate Immune Cascade for Cancer Immunotherapy of Malignant Ascites

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.

"Targeted plus controlled" - Composite nano delivery system opens the tumor vascular and microenvironment normalization window for anti-tumor therapy

The bottleneck of traditional anti-tumor therapy is mainly limited by the abnormal microenvironment of tumors. Leaky vessels are difficult for drugs or immune cells to penetrate deep into tumors, but tumor cells can easily escape through which and metastasize to other organs. Reprogramming the tumor microenvironment is one of the main directions for anti-cancer research, among which, tumor vascular normalization has received increasing attention. However, how to control the dose and time of anti-angiogenic drugs for stable vascular normalizing effect limits it for further research. We developed a composite nano delivery system, P-V@MG, with double delivery function of pH-responsibility and sustained drug release. The PHMEMA shell improves amphiphilicity of nano delivery system and prolongs in vivo retention, and releases V@MG in the weakly acidic tumor microenvironment, which slowly release anti-angiogenic drugs, Vandetanib. We found that P-V@MG not only prolonged the normalization window of tumor vascular but also reprogram tumor microenvironment with increased perfusion, immune cells infiltration and relieved hypoxia, which further opened the pathway for other anti-cancer therapeutics. This synergy was proved by the improving anti-tumor efficiency by combination of P-V@MG with the doxorubicin hydrochloride in 4 T1 breast cancer model suggesting the desirable value of pro-vascular normalization nano delivery systems in the field of anti-tumor combination therapy.

Immunotherapy for Peritoneal Carcinomatosis: Challenges and Prospective Outcomes

Peritoneal metastasis, also known as peritoneal carcinomatosis (PC), is a refractory cancer that is typically resistant to conventional therapies. The typical treatment for PC is a combination of cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC). Recently, research in this area has seen significant advances, particularly in immunotherapy as an alternative therapy for PC, which is very encouraging. Catumaxomab is a trifunctional antibody intraperitoneal (IP) immunotherapy authorized in Europe that can be used to diminish malignant ascites by targeting EpCAM. Intraperitoneal (IP) immunotherapy breaks immunological tolerance to treat peritoneal illness. Increasing T-cell responses and vaccination against tumor-associated antigens are two methods of treatment. CAR-T cells, vaccine-based therapeutics, dendritic cells (DCs) in combination with pro-inflammatory cytokines and NKs, adoptive cell transfer, and immune checkpoint inhibitors are promising treatments for PC. Carcinoembryonic antigen-expressing tumors are suppressed by IP administration of CAR-T cells. This reaction was strengthened by anti-PD-L1 or anti-Gr1. When paired with CD137 co-stimulatory signaling, CAR-T cells for folate receptor cancers made it easier for T-cell tumors to find their way to and stay alive in the body.