The efficacy of a novel vaccine approach using tumor cells that ectopically express a codon-optimized murine GM-CSF in a murine tumor model

Codon optimized influenza H1 HA sequence but not CTLA-4 targeting of HA antigen to enhance the efficacy of DNA vaccines in an animal model

Infections caused by the influenza virus lead to both epidemic and pandemic outbreaks in humans and animals. Owing to their rapid production, safety, and stability, DNA vaccines represent a promising avenue for eliciting immunity and thwarting viral infections. While DNA vaccines have demonstrated substantial efficacy in murine models, their effectiveness in larger animals remains subdued. This limitation may be addressed by augmenting the immunogenicity of DNA-based vaccines. In the investigation here, protein expression was enhanced via codon optimization and then mouse cytotoxic T-lymphocyte antigen 4 (CTLA-4) was harnessed as a modulatory adjunct to bind directly to antigen-presenting cells. Further, the study evaluated the immunogenicity of two variants of the hemagglutinin (HA) antigen, i.e. the full-length and the C-terminal deletion versions. The study findings revealed that the codon-optimized HA gene (pcHA) led to increased protein synthesis, as evidenced by elevated mRNA levels. Codon optimization also significantly bolstered both cellular and humoral immune responses. In cytokine assays, all plasmid constructs, particularly pCTLA4-cHA, induced robust interferon (IFN)-γ production, while interleukin (IL)-4 levels remained uniformly non-significant. Mice immunized with pcHA displayed an augmented presence of IFNγ+ T-cells, underscoring the enhanced potency of the codon-optimized HA vaccine. Contrarily, CTLA-4-fused DNA vaccines did not significantly amplify the immune response.

Targeted Drug Delivery Strategies for the Treatment of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) ranks among the most prevalent malignant tumors, exhibiting a high incidence rate that presents a substantial threat to human health. The use of sorafenib and lenvatinib, commonly employed as single-agent targeted inhibitors, complicates the treatment process due to the absence of definitive targeting. Nevertheless, the advent of nanotechnology has injected new optimism into the domain of liver cancer therapy. Nanocarriers equipped with active targeting or passive targeting mechanisms have demonstrated the capability to deliver drugs to tumor cells with high efficiency. This approach not only facilitates precise delivery to the affected site but also enables targeted drug release, thereby enhancing therapeutic efficacy. As medical technology progresses, there is an increasing call for innovative treatment modalities, including novel chemotherapeutic agents, gene therapy, phototherapy, immunotherapy, and combinatorial treatments for HCC. These emerging therapies are anticipated to yield improved clinical outcomes for patients, while minimizing systemic toxicity and adverse effects. Consequently, the application of nanotechnology is poised to significantly improve HCC treatment. This review focused on targeted strategies for HCC and the application of nanotechnology in this area.

Construction of PEI-EGFR-PD-L1-siRNA dual functional nano-vaccine and therapeutic efficacy evaluation for lung cancer

BACKGROUND

PD-1/PD-L1 tumor immunotherapy shows effective anticancer in treatment of solid tumors, so PEI lipid nanoparticles (PEI-LNP)/siRNA complex (EPV-PEI-LNP-SiRNA) with the therapeutic function of PD-L1-siRNA and EGFR short peptide/PD-L1 double immune-enhancing function were constructed for the prevention and treatment of EGFR-positive lung cancer in this study.

METHOD

In this study, PEI lipid nanoparticles (PEI-LNP)/siRNA complex (EPV-PEI-LNP-siRNA) with the therapeutic function of PD-L1-siRNA and EGFR short peptide/PD-L1 double immune-enhancing function were constructed for the prevention and treatment of EGFR-positive lung cancer and functional evaluation was conducted.

RESULTS

On the basis of the construction of the composite nano-drug delivery system, the binding capacity, cytotoxicity, apoptosis and uptake capacity of siRNA and EPV-PEI-LNP were tested in vitro, and the downregulation effect of PD-L1 on A549 cancer cells and the cytokine levels of cocultured T cells were tested. Lipid nanoparticles delivered siRNA and EGFR short peptide vaccine to non-small cell lung cancer (NSCLC), increasing tumor invasion and activation of CD8 + T cells. Combination therapy is superior to single target therapy.

CONCLUSION

Our constructed lipid nanoparticles of tumor targeted therapy gene siRNA combination had the ability to target cells in vitro and downregulate the expression of PD-L1, realizing the tumor-specific expression of immune-stimulating cytokines, which is a highly efficient and safe targeted therapy nano-vaccine.

A targeted siRNA-loaded PDL1-exosome and functional evaluation against lung cancer

BACKGROUND

As an endocytic nanosicle involved in intercellular communication, an exosome can efficiently deliver drugs from one cell to another and deliver therapeutic short interfering RNA (siRNA) to target cells. This is conducive to gene therapy for cancers. In this study, an exosome was used as the siRNA-loaded substrate to prepare a targeted siRNA-loaded PD-L1 exosome and evaluate its function against lung cancer.

METHODS

The optimal preparation process and binding ratio of the targeted nanovesicle/siRNA complex was determined by detecting the particle size, potential, and other physical parameters in combination with cell binding and uptake capacity of exosome complexes. The biological cell behavior of targeted exosome nanosicles was evaluated through cytotoxicity, apoptosis, and the cell uptake capacity.

RESULTS

A targeted exosome nanovesicle capable of loading siRNA and characterized with low toxicity, high loading rate, and the ability to be used for targeted tumor cell gene therapy was constructed.

CONCLUSION

The PD-L1 targeting exosome can be used as an efficient siRNA delivery carrier, which is an efficient and safe nanocarrier for tumor targeted gene therapy.

Enhancing immunogenicity of HPV16 E7 DNA vaccine by conjugating codon-optimized GM-CSF to HPV16 E7 DNA

OBJECTIVE

To generate immunity against human papillomavirus (HPV), the use of a recombinant DNA vaccine to carry an appropriate target gene is a promising and cost-effective approach. Granulocyte-macrophage colony-stimulating factor (GM-CSF) is a potent immunomodulatory cytokine that enhances the efficacy of vaccines by promoting the development and prolongation of humoral and cellular immunity. In this study, we linked codon-optimized GM-CSF (cGM-CSF) to the HPV16 E7 sequence as fused protein and evaluated the immunogenic potential of this DNA vaccine.

MATERIALS AND METHODS

We have demonstrated that cGM-CSF enhanced immunity against tumor challenges by generating and promoting the proliferation of HPV16 E7-specific CD8+ T cells, which secrete IFN-γ in the murine model. In this study, we aimed to evaluate the immunogenic potential of DNA vaccine that constructed by linking codon-optimized GM-CSF to HPV16 E7 sequence in the animal model. We study the half-life of RNA decay and cellular location of HPV16 E7 by Q-PCR and Western blot. We also assess immune response in the animal model by flow cytometry and ELISA.

RESULTS

The cGM-CSF-E7 sequence increased and extended the expression of E7 mRNA, in comparison with the E7 sequence alone. Mice vaccinated with the cGM-CSF-E7 DNA vaccine exhibited a slower rate of tumor growth than those vaccinated with the unconjugated E7 DNA vaccine. We also found that the CD4 and CD8+ T cells from these mice showed strong secretion of IFN-γ.

CONCLUSION

Through in vivo antibody depletion experiments, we demonstrated that both CD4+ and CD8+ T cells play an important role in the suppression of tumor growth.

Nanoparticle Delivery of MnO2 and Antiangiogenic Therapy to Overcome Hypoxia-Driven Tumor Escape and Suppress Hepatocellular Carcinoma

Antiangiogenic therapy is widely administered in many cancers, and the antiangiogenic drug sorafenib offers moderate benefits in advanced hepatocellular carcinoma (HCC). However, antiangiogenic therapy can also lead to hypoxia-driven angiogenesis and immunosuppression in the tumor microenvironment (TME) and metastasis. Here, we report the synthesis and evaluation of NanoMnSor, a tumor-targeted, nanoparticle drug carrier that efficiently codelivers oxygen-generating MnO₂ and sorafenib into HCC. We found that MnO₂ not only alleviates hypoxia by catalyzing the decomposition of H₂O₂ to oxygen but also enhances pH/redox-responsive T1-weighted magnetic resonance imaging and drug-release properties upon decomposition into Mn²⁺ ions in the TME. Moreover, macrophages exposed to MnO₂ displayed increased mRNA associated with the immunostimulatory M1 phenotype. We further show that NanoMnSor treatment leads to sorafenib-induced decrease in tumor vascularization and significantly suppresses primary tumor growth and distal metastasis, resulting in improved overall survival in a mouse orthotopic HCC model. Furthermore, NanoMnSor reprograms the immunosuppressive TME by reducing the hypoxia-induced tumor infiltration of tumor-associated macrophages, promoting macrophage polarization toward the immunostimulatory M1 phenotype, and increasing the number of CD8⁺ cytotoxic T cells in tumors, thereby augmenting the efficacy of anti-PD-1 antibody and whole-cell cancer vaccine immunotherapies. Our study demonstrates the potential of oxygen-generating nanoparticles to deliver antiangiogenic agents, efficiently modulate the hypoxic TME, and overcome hypoxia-driven drug resistance, thereby providing therapeutic benefit in cancer.

Highly efficient and tumor-selective nanoparticles for dual-targeted immunogene therapy against cancer

While immunotherapy holds great promise for combating cancer, the limited efficacy due to an immunosuppressive tumor microenvironment and systemic toxicity hinder the broader application of cancer immunotherapy. Here, we report a combinatorial immunotherapy approach that uses a highly efficient and tumor-selective gene carrier to improve anticancer efficacy and circumvent the systemic toxicity. In this study, we engineered tumor-targeted lipid-dendrimer-calcium-phosphate (TT-LDCP) nanoparticles (NPs) with thymine-functionalized dendrimers that exhibit not only enhanced gene delivery capacity but also immune adjuvant properties by activating the stimulator of interferon genes (STING)-cGAS pathway. TT-LDCP NPs delivered siRNA against immune checkpoint ligand PD-L1 and immunostimulatory IL-2-encoding plasmid DNA to hepatocellular carcinoma (HCC), increased tumoral infiltration and activation of CD8+ T cells, augmented the efficacy of cancer vaccine immunotherapy, and suppressed HCC progression. Our work presents nanotechnology-enabled dual delivery of siRNA and plasmid DNA that selectively targets and reprograms the immunosuppressive tumor microenvironment to improve cancer immunotherapy.

Delivery of nitric oxide with a nanocarrier promotes tumour vessel normalization and potentiates anti-cancer therapies

Abnormal tumour vasculature has a significant impact on tumour progression and response to therapy. Nitric oxide (NO) regulates angiogenesis and maintains vascular homeostasis and, thus, can be delivered to normalize tumour vasculature. However, a NO-delivery system with a prolonged half-life and a sustained release mechanism is currently lacking. Here we report the development of NanoNO, a nanoscale carrier that enables sustained NO release to efficiently deliver NO into hepatocellular carcinoma. Low-dose NanoNO normalizes tumour vessels and improves the delivery and effectiveness of chemotherapeutics and tumour necrosis factor-related, apoptosis-inducing, ligand-based therapy in both primary tumours and metastases. Furthermore, low-dose NanoNO reprogrammes the immunosuppressive tumour microenvironment toward an immunostimulatory phenotype, thereby improving the efficacy of cancer vaccine immunotherapy. Our findings demonstrate the ability of nanoscale NO delivery to efficiently reprogramme tumour vasculature and immune microenvironments to overcome resistance to cancer therapy, resulting in a therapeutic benefit.

Effect of Multiple Vaccinations with Tumor Cell-Based Vaccine with Codon-Modified GM-CSF on Tumor Growth in a Mouse Model

Ectopic expression of codon-modified granulocyte-macrophage colony-stimulating factor (cGM-CSF) in TC-1 cells (TC-1/cGM-CSF), a model cell line for human papillomavirus (HPV)-infected cervical cancer cells, increased the expression level of GM-CSF and improved the efficacy of tumor cell-based vaccines in a cervical cancer mouse model. The number of vaccine doses required to induce a long-term immune response in a cervical cancer mouse model is poorly understood. Here, we investigated one, three, and five doses of the irradiated TC-1/cGM-CSF vaccine to determine which dose was effective in inducing a greater immune response and the suppression of tumors. Our findings showed that three doses of irradiated TC-1/cGM-CSF vaccine elicited slower tumor growth rates and enhanced survival rates compared with one dose or five doses of irradiated TC-1/cGM-CSF vaccine. Consistently, mice vaccinated with three doses of irradiated TC-1/cGM-CSF vaccine exhibited stronger interferon gamma (IFN-γ) production in HPV E7-specific CD8⁺ T cells and CD4⁺ T cells. A higher percentage of natural killer cells and interferon-producing killer dendritic cells (IKDCs) appeared in the splenocytes of the mice vaccinated with three doses of irradiated TC-1/cGM-CSF vaccine compared with those of the mice vaccinated with one dose or five doses of irradiated TC-1/cGM-CSF vaccine. Our findings demonstrate that single or multiple vaccinations, such as five doses, with irradiated TC-1/cGM-CSF vaccine suppressed the immune response, whereas three doses of irradiated TC-1/cGM-CSF vaccine elicited a greater immune response and subsequent tumor suppression.

Biodegradable andrographolide-eluting nanofibrous membranes for the treatment of cervical cancer

BACKGROUND

In this study, we developed biodegradable andrographolide (AG)-eluting nanofibrous mats and evaluated their efficacy in treating cervical cancer.

MATERIALS AND METHODS

Membranes of two different poly[(d,l)-lactide-co-glycolide] (PLGA)-to-AG ratios (6:1 and 3:1) were prepared via electrospinning technology. The liberation behavior of AG was evaluated. A cervical cancer model with C57BL/6J mice was created and employed for an in vivo efficacy assessment of the drug-eluting nanofibers. Twelve mice with cervical cancer were stochastically divided into three different groups (four animals per group): group A received no treatment as the control, group B was treated with pure PLGA mats, and group C was treated with AG-loaded nanofibrous membranes. The changes in tumor sizes were recorded.

RESULTS

All membranes eluted high concentrations of AG at the target area for three weeks, while the systemic drug concentration in the blood remained low. Histological analysis showed no obvious tissue inflammation. Compared with the mice in groups A and B, the tumor size of the mice in group C decreased with time until day 25, when the daily drug concentration reduced to 3 µg/mL.

CONCLUSION

Biodegradable nanofibers with a sustainable release of AG exhibit adequate efficacy and durability for the treatment of mice with cervical cancer.

Development and application of a bioluminescent imaging mouse model for Chikungunya virus based on pseudovirus system

Chikungunya virus (CHIKV) is an arthropod-borne virus that is transmitted to humans primarily via the bite of an infected mosquito. Infection of humans by CHIKV can cause chikungunya fever which is an acute febrile illness associated with severe, often debilitating polyarthralgias. Since a re-emergence of CHIKV in 2004, the virus has spread into novel locations in nearly 40 countries including non-endemic regions and has led to millions of cases of disease throughout countries. Handling of CHIKV is restricted to the high-containment Biosafety Level 3 (BSL-3) facilities, which greatly impede the research progress of this virus. In this study, an envelope-pseudotyped virus expressing the firefly luciferase reporter protein (pHIV-CHIKV-Fluc) was generated. An in vitro sensitive neutralizing assay and an in vivo bioluminescent-imaging-based mouse infection model had been developed based on the CHIKV pseudovirus. Utilizing the platform, protection effect of DNA vaccine was evaluated. Therefore, this study provides a safe, sensitive and visualizing model for evaluating vaccines and antiviral therapies against CHIKV in low containment BSL-2 laboratories.

Novel GM-CSF-based vaccines: One small step in GM-CSF gene optimization, one giant leap for human vaccines

Granulocyte macrophage-colony stimulating factor (GM-CSF) is a potent immunomodulatory cytokine that is known to facilitate vaccine efficacy by promoting the development and prolongation of both humoral and cellular immunity. In the past years we have generated a novel codon-optimized GM-CSF gene as an adjuvant. The codon-optimized GM-CSF gene significantly increased protein expression levels in all cells tested and helped in generating a strong immune responses against HIV-1 Gag and HPV-associated cancer. Here, we review the literature dealing with the adjuvant activity of GM-CSF both in animal models and clinical trials. We anticipate that the codon-optimized GM-CSF gene offers a practical molecular strategy for potentiating immune responses to tumor cell-based vaccinations as well as other immunotherapeutic strategies.