Antitumor and immunomodulatory effects of recombinant fusion protein rMBP-NAP through TLR-2 dependent mechanism in tumor bearing mice

Unveiling the gastric microbiota: implications for gastric carcinogenesis, immune responses, and clinical prospects

High-throughput sequencing has ushered in a paradigm shift in gastric microbiota, breaking the stereotype that the stomach is hostile to microorganisms beyond H. pylori. Recent attention directed toward the composition and functionality of this 'community' has shed light on its potential relevance in cancer. The microbial composition in the stomach of health displays host specificity which changes throughout a person's lifespan and is subject to both external and internal factors. Distinctive alterations in gastric microbiome signature are discernible at different stages of gastric precancerous lesions and malignancy. The robust microbes that dominate in gastric malignant tissue are intricately implicated in gastric cancer susceptibility, carcinogenesis, and the modulation of immunosurveillance and immune escape. These revelations offer fresh avenues for utilizing gastric microbiota as predictive biomarkers in clinical settings. Furthermore, inter-individual microbiota variations partially account for differential responses to cancer immunotherapy. In this review, we summarize current literature on the influence of the gastric microbiota on gastric carcinogenesis, anti-tumor immunity and immunotherapy, providing insights into potential clinical applications.

Role of Helicobacter pylori virulence factors and alteration of the Tumor Immune Microenvironment: challenges and opportunities for Cancer Immunotherapy

Various forms of malignancies have been linked to Helicobacter pylori. Despite advancements in chemotherapeutic and surgical approaches, the management of cancer, particularly at advanced stages, increasingly relies on the integration of immunotherapy. As a novel, safe therapeutic modality, immunotherapy harnesses the immune system of the patient to treat cancer, thereby broadening treatment options. However, there is evidence that H. pylori infection may influence the effectiveness of immunotherapy in various types of cancer. This association is related to H. pylori virulence factors and the tumor microenvironment. This review discusses the influence of H. pylori infection on immunotherapy in non-gastrointestinal and gastrointestinal tumors, the mechanisms underlying this relationship, and directions for the development of improved immunotherapy strategies.

Unleashing nature's potential and limitations: Exploring molecular targeted pathways and safe alternatives for the treatment of multiple sclerosis (Review)

Driven by the limitations and obstacles of the available approaches and medications for multiple sclerosis (MS) that still cannot treat the disease, but only aid in accelerating the recovery from its attacks, the use of naturally occurring molecules as a potentially safe and effective treatment for MS is being explored in model organisms. MS is a devastating disease involving the brain and spinal cord, and its symptoms vary widely. Multiple molecular pathways are involved in the pathogenesis of the disease. The present review showcases the recent advancements in harnessing nature's resources to combat MS. By deciphering the molecular pathways involved in the pathogenesis of the disease, a wealth of potential therapeutic agents is uncovered that may revolutionize the treatment of MS. Thus, a new hope can be envisioned in the future, aiming at paving the way toward identifying novel safe alternatives to improve the lives of patients with MS.

The Role of Helicobacter pylori Neutrophil-Activating Protein in the Pathogenesis of H. pylori and Beyond: From a Virulence Factor to Therapeutic Targets and Therapeutic Agents

Helicobacter pylori neutrophil-activating protein (HP-NAP), a major virulence factor of H. pylori, plays a role in bacterial protection and host inflammation. HP-NAP activates a variety of innate immune cells, including neutrophils, monocytes, and mast cells, to induce their pro-oxidant and pro-inflammatory activities. This protein also induces T-helper type 1 (Th1) immune response and cytotoxic T lymphocyte (CTL) activity, supporting that HP-NAP is able to promote gastric inflammation by activation of adaptive immune responses. Thus, HP-NAP is a potential therapeutic target for the treatment of H. pylori-induced gastric inflammation. The inflammatory responses triggered by HP-NAP are mediated by a PTX-sensitive G protein-coupled receptor and Toll-like receptor 2. Drugs designed to block the interactions between HP-NAP and its receptors could alleviate the inflammation in gastric mucosa caused by H. pylori infection. In addition, HP-NAP acts as a promising therapeutic agent for vaccine development, allergy treatment, and cancer immunotherapy. The high antigenicity of HP-NAP makes this protein a component of vaccines against H. pylori infection. Due to its immunomodulatory activity to stimulate the Th1-inducing ability of dendritic cells, enhance Th1 immune response and CTL activity, and suppress Th2-mediated allergic responses, HP-NAP could also act as an adjuvant in vaccines, a drug candidate against allergic diseases, and an immunotherapeutic agent for cancer. This review highlights the role of HP-NAP in the pathogenesis of H. pylori and the potential for this protein to be a therapeutic target in the treatment of H. pylori infection and therapeutic agents against H. pylori-associated diseases, allergies, and cancer.

Preparation of Water-Soluble Acetylaminoglucan with Low Molecular Weight and Its Anti-Tumor Activity on H22 Tumor-Bearing Mice

In this study, a novel low molecular weight of acetylaminoglucan (AGA) was obtained and its antitumor activity on H22 tumor-bearing mice was investigated. The results of UV, HPLC and FT-IR showed that AGA present high purity with low molecular weight of 2.76 × 103 Da. Animal experiments showed that AGA could inhibit the proliferation of tumor cells in H22 tumor-bearing mice by protecting the immune organs, enhancing the phagocytosis ability of macrophages, killing activity of NK cells and proliferation capacity of lymphocytes, improving the levels of cytokines in vivo and regulating the distribution of lymphocyte subsets, and the tumor inhibition rate reached to 52.74% (50 mg/kg). Cell cycle determination further indicated that AGA could induce apoptosis of tumor cells and arrests it in S phase. These results will provide a data basis for the potential application of AGA in pharmaceutical industry.

Effect of Helicobacter pylori on immunotherapy is gaining more attention

BACKGROUND

Immunotherapy, especially immune checkpoint inhibitors, has been widely used in tumor therapy and have shown ideal clinical efficacy. However, some cancers still do not respond to PD-1/PD-L1 blockade therapy effectively. Helicobacter pylori infection might affect the curative effect of immunotherapy while it is rarely reported. We aimed to visualize the research hotspots and trends of H. pylori and immunotherapy using a bibliometric analysis to help understand the future development of basic and clinical research.

METHODS

The relevant publications on H. pylori and immunotherapy were searched on April 20, 2022, in the Web of Science Core Collection Database (WOSCC). The document types were limited to articles and reviews. The VOSviewer 1.6.16 software was used to assess the co-authorship, co-occurrence, citation of countries, institutions, authors, journals, and hotspot keywords. The research status and trend change of H. pylori and immunotherapy were analyzed by bibliometric analysis.

RESULTS

A total of 95 studies authored by 561 researchers were eventually included in this study. The majority of the retrieved studies were 55 (58%) original research articles. China conducted the greatest number of studies, followed by USA and Italy. The related topics included the following three aspects: the relationship between microorganisms and cancer, the relationship between gastric cancer and immunity, and the relationship between H. pylori and immunotherapy, including purified/cloned components of H. pylori acting as efficient adjuvant to boost tumor responses and H. pylori infection which modulate host immune responses and impact on the efficacy of antitumor immunity initiated by immune checkpoint inhibitors. The timing diagram revealed that the current research hotspots focused on effects of microorganisms on immunotherapy.

CONCLUSION

The effect of H. pylori on cancer immunotherapy is getting more and more attention in these years. It still remains uncertain, and more studies are needed in the future.

Effects of helicobacter pylori on tumor microenvironment and immunotherapy responses

Helicobacter pylori is closely associated with gastric cancer. During persistent infection, Helicobacter pylori can form a microenvironment in gastric mucosa which facilitates the survival and colony formation of Helicobacter pylori. Tumor stromal cells are involved in this process, including tumor-associated macrophages, mesenchymal stem cells, cancer-associated fibroblasts, and myeloid-derived suppressor cells, and so on. The immune checkpoints are also regulated by Helicobacter pylori infection. Helicobacter pylori virulence factors can also act as immunogens or adjuvants to elicit or enhance immune responses, indicating their potential applications in vaccine development and tumor immunotherapy. This review highlights the effects of Helicobacter pylori on the immune microenvironment and its potential roles in tumor immunotherapy responses.

TLR agonist rMBP-NAP inhibits B16 melanoma tumor growth via induction of DCs maturation and T-cells cytotoxic response

Melanoma is the most aggressive skin cancer with increasing incidence and poor prognosis all over the world. Recent research has found that immunological abnormalities played a key role in the pathogenesis of melanoma. Increased understanding of tumor immune mechanisms has led to attract more attention for the potential of TLR agonists on treatment of melanoma. The present study aimed to determine the potential and efficacy of a novel TLR agonist rMBP-NAP for antitumor treatment in murine model of B16 melanoma. Subcutaneous administration of mice with rMBP-NAP remarkably inhibited tumor growth and tumor inhibitory rate was 77.72%. Additionally, rMBP‑NAP significantly upregulated the number of mature DCs (P < 0.05). Furthermore, the number and activation of CD4⁺ and CD8⁺ T cells were prominently enhanced following rMBP-NAP stimulation (P < 0.05). Overall, these results demonstrated that rMBP-NAP possessed the potential to be a novel immunomodulatory candidate drug for treating melanoma.

HP-NAP of Helicobacter pylori: The Power of the Immunomodulation

The miniferritin HP-NAP of Helicobacter pylori was originally described as a neutrophil-activating protein because of the capacity to activate neutrophils to generate oxygen radicals and adhere to endothelia. Currently, the main feature for which HP-NAP is known is the ability to promote Th1 responses and revert the immune suppressive profile of macrophages. In this review, we discuss the immune modulating properties of the protein regarding the H. pylori infection and the evidence that support the potential clinical application of HP-NAP in allergy and cancer immunotherapy.

Inflammatory Role of TLR-MyD88 Signaling in Multiple Sclerosis

Multiple sclerosis (MS) is a neuro-autoimmune and neurodegenerative disorder leading to chronic inflammation, demyelination, axonal, and neuronal loss in the central nervous system (CNS). Despite intense research efforts, the pathogenesis of MS still remains unclear. Toll-like receptors (TLRs) are a family of type I transmembrane receptors that play a crucial role in the innate immune response. Myeloid differentiation factor 88 (MyD88) is the adaptor of major TLRs. It has been widely considered that the TLR-MyD88 signaling pathway plays an important role in the occurrence and development of autoimmune disease. Data have revealed that the TLR-MyD88 signaling may be involved in the pathogenesis of MS and experimental autoimmune encephalomyelitis (EAE), an animal model for MS, by regulating the antigen presentation of dendritic cells, the integrity of blood-brain barrier (BBB), and the activation of T cells and B cells. Here, we summarize the role of TLRs and MyD88 in MS and discuss the possible therapies that are based on these molecules.

Toll-like receptor agonist rMBP-NAP enhances antitumor cytokines production and CTL activity of peripheral blood mononuclear cells from patients with lung cancer

Toll-like receptor (TLR) agonists are known for their ability to inhibit tumor progression via enhancing antitumor cytokines production and cytotoxic T lymphocyte (CTL) activity. Recombinant Helicobacter pylori neutrophil-activating protein fused with maltose-binding protein (rMBP-NAP) has been reported as a novel TLR agonist for antitumor treatment in murine models. The present study aimed to determine the potential and efficacy of the rMBP-NAP for antitumor treatment prior to further clinical trials. The rMBP-NAP was expressed and purified for subsequent experiments. Peripheral blood mononuclear cells (PBMCs) from health donors and patients with lung cancer (LC) were incubated with PBS and 0.2 mg/ml rMBP-NAP. Antitumor cytokines production was assayed using ELISA and reverse transcription-quantitative polymerase chain reaction analysis. The cytolytic activity of PBMCs and the number of Interferon-γ (IFN-γ)-secreting cells were assayed using lactate dehydrogenase and Enzyme-linked ImmunoSpot assays, respectively. The results from the present study revealed that the expression of IFN-γ, interleukin (IL)-2, tumor necrosis factor-α and IL-12 of PBMCs from patients with LC and healthy donors were significantly increased following treatment with rMBP-NAP (P<0.05). Additionally, rMBP-NAP significantly upregulated the number of IFN-γ-secreting cells in PBMCs and prominently increased the cytotoxic activity of PBMCs (P<0.05). Furthermore, the expression of TLR2 was significantly enhanced following rMBP-NAP stimulation (P<0.05), which indicated that rMBP-NAP may serve an antitumor role via TLR2 signaling pathways. Overall, these results demonstrated that rMBP-NAP possesses the potential to be a novel immunomodulatory candidate drug and requires further evaluation in clinical trials.

Production and delivery of Helicobacter pylori NapA in Lactococcus lactis and its protective efficacy and immune modulatory activity

Helicobacter pylori neutrophil-activating protein A subunit (NapA) has been identified as a virulence factor, a protective antigen and a potent immunomodulator. NapA shows unique application potentials for anti-H. pylori vaccines and treatment strategies of certain allergic diseases and carcinomas. However, appropriate production and utilization modes of NapA still remain uncertain to date. This work has established a novel efficient production and utilization mode of NapA by using L. lactis as an expression host and delivery vector, and demonstrated immune protective efficacy and immune modulatory activity of the engineered L. lactis by oral vaccination of mice. It was observed for the first time that H. pylori NapA promotes both polarized Th17 and Th1 responses, which may greatly affect the clinical application of NapA. This report offers a promising anti-H. pylori oral vaccine candidate and a potent mucosal immune modulatory agent. Meanwhile, it uncovers a way to produce and deliver the oral vaccine and immunomodulator by fermentation of food like milk, which might have striking effects on control of H. pylori infection, gastrointestinal cancers, and Th2 bias allergic diseases, including many food allergies.

Recombinant protein rMBP-NAP restricts tumor progression by triggering antitumor immunity in mouse metastatic lung cancer

Recombinant Helicobacter pylori neutrophil-activating protein fused with maltose-binding protein (rMBP-NAP), a potential TLR2 ligand, was reported to possess immunomodulatory effects on in situ tumors in our previous study. In the present work, we attempt to elucidate the effect of rMBP-NAP at the local immune modulation in B16-F10-induced metastatic lung cancer. Our results demonstrated that growth of B16-F10 melanoma metastases in the lung was significantly arrested after rMBP-NAP treatment, along with marked reduction in metastatic lung nodules and significant increase in survival. The treatment induced both local and systemic immune responses, which were associated with higher influx of CD4⁺/CD8⁺ T cells and drove toward Th1-like and cytotoxic immune environment. Moreover, rMBP-NAP also showed significant anti-angiogenic activity by reducing vascularization in lung tumor sections. rMBP-NAP could induce antitumor immunity through activating Th1 cells and producing pro-inflammatory cytokines, which are responsible for the effective cytotoxic immune response against cancer progression. Our findings indicate that rMBP-NAP might be a novel antitumor therapeutic strategy.