TNFR2: A Novel Target for Cancer Immunotherapy

Secondary metabolites of Alternaria alternate appraisal of their SARS-CoV-2 inhibitory and anti-inflammatory potentials

This study identifies the secondary metabolites from Alternaria alternate and evaluates their ACE-2: Spike RBD (SARS-CoV-2) inhibitory activity confirmed via immunoblotting in human lung microvascular endothelial cells. In addition, their in vitro anti-inflammatory potential was assessed using a cell-based assay in LPS-treated RAW 264.7 macrophage cells. Two novel compounds, altenuline (1), phthalic acid bis (7'/7'' pentyloxy) isohexyl ester (2), along with 1-deoxyrubralactone (3) alternariol-5-O-methyl ether (4) and alternariol (5) were identified. Molecular docking and in vitro studies showed that compounds 2 and 4 were promising to counteract SARS-CoV-2 attachment to human ACE-2. Thus, they are considered promising natural anti-viral agents. SwissADME in silico analysis was conducted to predict the drug-like potential. Immunoblotting analysis confirmed that the tested compounds (1-4) demonstrated downregulation of ACE-2 expression in the endothelial cells from the lungs with variable degrees. Furthermore, the tested compounds (1-4) showed promising anti-inflammatory activities through TNF-α: TNFR2 inhibitory activity and their inhibitory effect on the proinflammatory cytokines (TNF-α and IL-6) in LPS-stimulated monocytes. In conclusion, our study, for the first time, provides beneficial experimental confirmation for the efficiency of the A. alternate secondary metabolites for the treatment of COVID-19 as they hinder SARS-CoV-2 infection and lower inflammatory responses initiated by SARS-CoV-2. A. alternate and its metabolites are considered in developing preventative and therapeutic tactics for COVID-19.

Soluble B7 and TNF family in colorectal cancer: Serum level, prognostic and treatment value

Soluble immune checkpoints (sIC) are crucial factors in the immune system. They regulate immune responses by transforming intercellular signals via binding to their membrane-bound receptor or ligand. Moreover, soluble ICs are vital in immune regulation, cancer development, and prognosis. They can be identified and measured in various tumor microenvironments. Recently, sICs have become increasingly important in clinically assessing malignancies like colorectal cancer (CRC) patients. This review explores the evolving role of the soluble B7 family and soluble tumor necrosis factor (TNF) superfamily members in predicting disease progression, treatment response, and overall patient outcomes in CRC. We comprehensively analyze the diagnostic and prognostic potential of soluble immune checkpoints in CRC. Understanding the role of these soluble immune checkpoints in CRC management and their potential as targets for precision medicine approaches can be critical for improving outcomes for patients with colorectal cancer.

The implications of the TNFα-TNFR2 immune checkpoint signaling pathway in cancer treatment: From immunoregulation to angiogenesis

Despite the tremendous advances that have been made in biomedical research, cancer remains one of the leading causes of death worldwide. Several therapeutic approaches have been suggested and applied to treat cancer with impressive results. Immunotherapy based on targeting immune checkpoint signaling pathways proved to be one of the most efficient. In this review article, we will focus on the recently discovered TNFα-TNFR2 signaling pathway, which controls the immunological and pro-angiogenic properties of many immunoregulatory and pro-angiogenic cells such as endothelial progenitor cells (EPCs), mesenchymal stem cells (MSCs), and regulatory T cells (Tregs). Due to their biological properties, these cells can play a major role in cancer progression and metastasis. Therefore, we will discuss the advantages and disadvantages of an anti-TNFR2 treatment that could carry two faces under one hood. It interrupts the immunosuppressive and pro-angiogenic behaviors of the above-mentioned cells and interferes with tumor growth and survival.

Lactylation-driven TNFR2 expression in regulatory T cells promotes the progression of malignant pleural effusion

BACKGROUND

Although tumor necrosis factor receptor 2 (TNFR2) has been recognized as an attractive next-generation candidate target for cancer immunotherapy, the factors that regulate the gene expression and their mechanistic effects on tumor-infiltrating regulatory T cells (Treg cells) remain poorly understood.

METHODS

Single-cell RNA sequencing analysis was employed to analyze the phenotypic and functional differences between TNFR2+ Treg cells and TNFR2- Treg cells. Malignant pleural effusion (MPE) from humans and mouse was used to investigate the potential mechanisms by which lactate regulates TNFR2 expression.

RESULTS

Treg cells with high TNFR2 expression exhibited elevated levels of immune checkpoint molecules. Additionally, the high expression of TNFR2 on Treg cells was positively correlated with a poor prognosis in MPE patients. Moreover, we revealed that lactate upregulated TNFR2 expression on Treg cells, thereby enhancing their immunosuppressive function in MPE. Mechanistically, lactate modulated the gene transcription of transcription factor nuclear factor-κB p65 (NF-κB p65) through histone H3K18 lactylation (H3K18la), subsequently upregulating the gene expression of TNFR2 and expediting the progression of MPE. Notably, lactate metabolism blockade combined with immune checkpoint blockade (ICB) therapy effectively enhanced the efficacy of ICB therapy, prolonged the survival time of MPE mice, and improved immunosuppression in the microenvironment of MPE.

CONCLUSIONS

The study explains the mechanism that regulates TNFR2 expression on Treg cells and its function in MPE progression, providing novel insights into the epigenetic regulation of tumor development and metabolic strategies for MPE treatment by targeting lactate metabolism in Treg cells.

In situ blockade of TNF-TNFR2 axis via oncolytic adenovirus improves antitumor efficacy in solid tumors

Tumor necrosis factor (TNF) has been recognized as an immune activation factor in tumor immunotherapy. Our study demonstrated that TNF blockade markedly enhanced the antitumor efficacy of oncolytic adenovirus (AdV) therapy. To minimize systemic side effects, we engineered a recombinant oncolytic AdV encoding a TNF inhibitor (AdV-TNFi) to confine TNF blockade within the tumor microenvironment (TME). AdV-TNFi significantly improved therapeutic outcomes across various solid tumor models, including four murine and two golden hamster cancers. Immune cell profiling identified CD8+ T cells as the primary mediators of AdV-TNFi-induced antitumor effects, rather than CD4+ T or NK cells. Additionally, AdV-TNFi significantly decreased the infiltration of suppressive myeloid-derived immune cells within the TME and promoted long-term antitumor immune surveillance. Further investigation indicated that TNFR2, more than TNFR1, is pertinent to the immunosuppressive TME, with a recombinant AdV-encoding anti-TNFR2 demonstrating comparable antitumor efficacy to AdV-TNFi. Moreover, AdV-TNFi enhanced the antitumor efficacy of gemcitabine and immune checkpoint blockades (ICBs), such as anti-PD-L1 and anti-TIGIT antibodies, in pancreatic carcinoma and the anti-EGFR antibody in colon carcinoma. In conclusion, intratumoral blockade of the TNF/TNFR2 axis using AdV augments cancer immunotherapy efficacy while mitigating the risks associated with systemic TNF or TNFR2 suppression, warranting further clinical investigation.

Anti-TNFR2 Antibody-Conjugated PLGA Nanoparticles for Targeted Delivery of Adriamycin in Mouse Colon Cancer

High levels of tumor necrosis factor receptor type II (TNFR2) are preferentially expressed by immunosuppressive CD4+Foxp3+ regulatory T cells (Tregs), especially those present in the tumor microenvironment, as initially reported by us. There is compelling evidence that targeting TNFR2 markedly enhances antitumor immune responses. Furthermore, a broad spectrum of human cancers also expresses TNFR2, while its expression by normal tissue is very limited. We thus hypothesized that TNFR2 may be harnessed for tumor-targeted delivery of chemotherapeutic agents. In this study, we performed a proof-of-concept study by constructing a TNFR2-targeted PEGylated poly(dl-lactic-co-glycolic acid) (PLGA-PEG) nanodrug delivery system [designated as TNFR2-PLGA-ADR (Adriamycin)]. The results of in vitro study showed that this TNFR2-targeted delivery system had the properties in cellular binding and cytotoxicity toward mouse colon cancer cells. Further, upon intravenous injection, TNFR2-PLGA-ADR could efficiently accumulate in MC38 and CT26 mouse colon tumor tissues and preferentially bind with tumor-infiltrating Tregs. Compared with ADR and ISO-PLGA-ADR, the in vivo antitumor effect of TNFR2-PLGA-ADR was markedly enhanced, which was associated with a decrease of TNFR2+ Tregs and an increase of IFNγ+CD8+ cytotoxic T lymphocytes in the tumor tissue. Therefore, our results clearly show that targeting TNFR2 is a promising strategy for designing tumor-specific chemoimmunotherapeutic agent delivery system.

Targeting TNFR2 for cancer immunotherapy: recent advances and future directions

Cancer is the leading cause of death worldwide, accounting for nearly 10 million deaths every year. Immune checkpoint blockade approaches have changed the therapeutic landscape for many tumor types. However, current immune checkpoint inhibitors PD-1 or CTLA-4 are far from satisfactory, due to high immune-related adverse event incident (up to 60%) and the inefficiency in cases of "cold" tumor microenvironment. TNFR2, a novel hopeful tumor immune target, was initially proposed in 2017. It not only promotes tumor cell proliferation, but also correlates with the suppressive function of Treg cells, implicating in the development of an immunosuppressive tumor microenvironment. In preclinical studies, TNFR2 antibody therapy has demonstrated efficacy alone or a potential synergistic effect when combined with classical PD-1/ CTLA-4 antibodies. The focus of this review is on the characteristics, functions, and recent advancements in TNFR2 therapy, providing a new direction for the next generation of anti-tumor alternative therapy.

Immune-inflammatory modulation by natural products derived from edible and medicinal herbs used in Chinese classical prescriptions

BACKGROUND

Edible and medicinal herbs1 (EMHs) refer to a class of substances with dual attribution of food and medicine. These substances are traditionally used as food and also listed in many international pharmacopoeias, including the European Pharmacopoeia, the United States Pharmacopoeia, and the Chinese Pharmacopoeia. Some classical formulas that are widely used in traditional Chinese medicine include a series of EMHs, which have been shown to be effective with obvious characteristics and advantages. Notably, these EMHs and Chinese classical prescriptions2 (CCPs) have also attracted attention in international herbal medicine research because of their low toxicity and high efficiency as well as the rich body of experience for their long-term clinical use.

PURPOSE

Our purpose is to explore the potential therapeutic effect of EMHs with immune-inflammatory modulation for the study of modern cancer drugs.

STUDY DESIGN

In the present study, we present a detailed account of some EMHs used in CCPs that have shown considerable research potential in studies exploring modern drugs with immune-inflammatory modulation.

METHODS

Approximately 500 publications in the past 30 years were collected from PubMed, Web of Science and ScienceDirect using the keywords, such as natural products, edible and medicinal herbs, Chinese medicine, classical prescription, immune-inflammatory, tumor microenvironment and some related synonyms. The active ingredients instead of herbal extracts or botanical mixtures were focused on and the research conducted over the past decade were discussed emphatically and analyzed comprehensively.

RESULTS

More than ten natural products derived from EMHs used in CCPs are discussed and their immune-inflammatory modulation activities, including enhancing antitumor immunity, regulating inflammatory signaling pathways, lowering the proportion of immunosuppressive cells, inhibiting the secretion of proinflammatory cytokines, immunosuppressive factors, and inflammatory mediators, are summarized.

CONCLUSION

Our findings demonstrate the immune-inflammatory modulating role of those EMHs used in CCPs and provide new ideas for cancer treatment in clinical settings.

Tumor Necrosis Factor Receptor-2 Signals Clear-Cell Renal Carcinoma Proliferation via Phosphorylated 4E Binding Protein-1 and Mitochondrial Gene Translation

Clear-cell renal cell carcinoma (ccRCC), a tubular epithelial malignancy, secretes tumor necrosis factor (TNF), which signals ccRCC cells in an autocrine manner via two cell surface receptors, TNFR1 and TNFR2, to activate shared and distinct signaling pathways. Selective ligation of TNFR2 drives cell cycle entry of malignant cells via a signaling pathway involving epithelial tyrosine kinase, vascular endothelial cell growth factor receptor type 2, phosphatidylinositol-3-kinase, Akt, pSer727-Stat3, and mammalian target of rapamycin. In this study, phosphorylated 4E binding protein-1 (4EBP1) serine 65 (pSer65-4EBP1) was identified as a downstream target of this TNFR2 signaling pathway. pSer65-4EBP1 expression was significantly elevated relative to total 4EBP1 in ccRCC tissue compared with that in normal kidneys, with signal intensity increasing with malignant grade. Selective ligation of TNFR2 with the TNFR2-specific mutein increased pSer65-4EBP1 expression in organ cultures that co-localized with internalized TNFR2 in mitochondria and increased expression of mitochondrially encoded COX (cytochrome c oxidase subunit) Cox1, as well as nuclear-encoded Cox4/5b subunits. Pharmacologic inhibition of mammalian target of rapamycin reduced both TNFR2-specific mutein-mediated phosphorylation of 4EBP1 and cell cycle activation in tumor cells while increasing cell death. These results signify the importance of pSer65-4EBP1 in mediating TNFR2-driven cell-cycle entry in tumor cells in ccRCC and implicate a novel relationship between the TNFR2/pSer65-4EBP1/COX axis and mitochondrial function.

Tumor microenvironment as niche constructed by cancer stem cells: Breaking the ecosystem to combat cancer

BACKGROUND

Cancer stem cells (CSCs) are a distinct subpopulation of cancer cells with the capacity to constantly self-renew and differentiate, and they are the main driver in the progression of cancer resistance and relapse. The tumor microenvironment (TME) constructed by CSCs is the "soil" adapted to tumor growth, helping CSCs evade immune killing, enhance their chemical resistance, and promote cancer progression.

AIM OF REVIEW

We aim to elaborate the tight connection between CSCs and immunosuppressive components of the TME. We attempt to summarize and provide a therapeutic strategy to eradicate CSCs based on the destruction of the tumor ecological niche.

KEY SCIENTIFIC CONCEPTS OF REVIEW

This review is focused on three main key concepts. First, we highlight that CSCs recruit and transform normal cells to construct the TME, which further provides ecological niche support for CSCs. Second, we describe the main characteristics of the immunosuppressive components of the TME, targeting strategies and summarize the progress of corresponding drugs in clinical trials. Third, we explore the multilevel insights of the TME to serve as an ecological niche for CSCs.

Regulating Tumor-Associated Macrophage Polarization by Cyclodextrin-Modified PLGA Nanoparticles Loaded with R848 for Treating Colon Cancer

Purpose

This study aimed to develop a novel and feasible modification strategy to improve the solubility and antitumor activity of resiquimod (R848) by utilizing the supramolecular effect of 2-hydroxypropyl-beta-cyclodextrin (2-HP-β-CD).

Methods

R848-loaded PLGA nanoparticles modified with 2-HP-β-CD (CD@R848@NPs) were synthesized using an enhanced emulsification solvent-evaporation technique. The nanoparticles were then characterized in vitro by several methods, such as scanning electron microscopy (SEM), differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) spectroscopy, particle size analysis, and zeta potential analysis. Then, the nanoparticles were loaded with IR-780 dye and imaged using an in vivo imaging device to evaluate their biodistribution. Additionally, the antitumor efficacy and underlying mechanism of CD@R848@NPs in combination with an anti-TNFR2 antibody were investigated using an MC-38 colon adenocarcinoma model in vivo.

Results

The average size of the CD@R848@NPs was 376 ± 30 nm, and the surface charge was 21 ± 1 mV. Through this design, the targeting ability of 2-HP-β-CD can be leveraged and R848 is delivered to tumor-supporting M2-like macrophages in an efficient and specific manner. Moreover, we used an anti-TNFR2 antibody to reduce the proportion of Tregs. Compared with plain PLGA nanoparticles or R848, CD@R848@NPs increased penetration in tumor tissues, dramatically reprogrammed M1-like macrophages, removed tumors and prolonged patient survival.

Conclusion

The new nanocapsule system is a promising strategy for targeting tumor, reprogramming tumor -associated macrophages, and enhancement immunotherapy.

TNF receptor 2 knockout mouse had reduced lung cancer growth and schizophrenia-like behavior through a decrease in TrkB-dependent BDNF level

The relationship between schizophrenia (SCZ) and cancer development remains controversial. Based on the disease-gene association platform, it has been revealed that tumor necrosis factor receptor (TNFR) could be an important mediatory factor in both cancer and SCZ development. TNF-α also increases the expression of brain-derived neurotrophic factor (BDNF) and tropomyosin receptor kinase B (TrkB) in the development of SCZ and tumor, but the role of TNFR in mediating the association between the two diseases remains unclear. We studied the vital roles of TNFR2 in the progression of tumor and SCZ-like behavior using A549 lung cancer cell xenografted TNFR2 knockout mice. TNFR2 knockout mice showed significantly decreased tumor size and weight as well as schizophrenia-like behaviors compared to wild-type mice. Consistent with the reduced tumor growth and SCZ-like behaviors, the levels of TrkB and BDNF expression were significantly decreased in the lung tumor tissues and pre-frontal cortex of TNFR2 knockout mice. However, intravenous injection of BDNF (160 μg/kg) to TNFR2 knockout mice for 4 weeks increased tumor growth and SCZ-like behaviors as well as TrkB expression. In in vitro study, significantly decreased cell growth and expression of TrkB and BDNF by siTNFR2 transfection were found in A549 lung cancer cells. However, the addition of BDNF (100 ng/ml) into TNFR2 siRNA transfected A549 lung cancer cells recovered cell growth and the expression of TrkB. These results suggest that TNFR2 could be an important factor in mediating the comorbidity between lung tumor growth and SCZ development through increased TrkB-dependent BDNF levels.

Cellular heterogeneity in TNF/TNFR1 signalling: live cell imaging of cell fate decisions in single cells

Cellular responses to TNF are inherently heterogeneous within an isogenic cell population and across different cell types. TNF promotes cell survival by activating pro-inflammatory NF-κB and MAPK signalling pathways but may also trigger apoptosis and necroptosis. Following TNF stimulation, the fate of individual cells is governed by the balance of pro-survival and pro-apoptotic signalling pathways. To elucidate the molecular mechanisms driving heterogenous responses to TNF, quantifying TNF/TNFR1 signalling at the single-cell level is crucial. Fluorescence live-cell imaging techniques offer real-time, dynamic insights into molecular processes in single cells, allowing for detection of rapid and transient changes, as well as identification of subpopulations, that are likely to be missed with traditional endpoint assays. Whilst fluorescence live-cell imaging has been employed extensively to investigate TNF-induced inflammation and TNF-induced cell death, it has been underutilised in studying the role of TNF/TNFR1 signalling pathway crosstalk in guiding cell-fate decisions in single cells. Here, we outline the various opportunities for pathway crosstalk during TNF/TNFR1 signalling and how these interactions may govern heterogenous responses to TNF. We also advocate for the use of live-cell imaging techniques to elucidate the molecular processes driving cell-to-cell variability in single cells. Understanding and overcoming cellular heterogeneity in response to TNF and modulators of the TNF/TNFR1 signalling pathway could lead to the development of targeted therapies for various diseases associated with aberrant TNF/TNFR1 signalling, such as rheumatoid arthritis, metabolic syndrome, and cancer.

TNFRSF1B Gene Variants in Clinicopathological Aspects and Prognosis of Patients with Cutaneous Melanoma

Regulatory T lymphocytes play a critical role in immune regulation and are involved in the aberrant cell elimination by facilitating tumor necrosis factor connection to the TNFR2 receptor, encoded by the TNFRSF1B polymorphic gene. We aimed to examine the effects of single nucleotide variants TNFRSF1B c.587T>G, c.*188A>G, c.*215C>T, and c.*922C>T on the clinicopathological characteristics and survival of cutaneous melanoma (CM) patients. Patients were genotyped using RT-PCR. TNFRSF1B levels were measured using qPCR. Luciferase reporter assay evaluated the interaction of miR-96 and miR-1271 with the 3'-UTR of TNFRSF1B. The c.587TT genotype was more common in patients younger than 54 years old than in older patients. Patients with c.*922CT or TT, c.587TG or GG + c.*922CT or TT genotypes, as well as those with the haplotype TATT, presented a higher risk of tumor progression and death due to the disease effects. Individuals with the c.*922TT genotype had a higher TNFRSF1B expression than those with the CC genotype. miR-1271 had less efficient binding with the 3'-UTR of the T allele when compared with the C allele of the SNV c.*922C>T. Our findings, for the first time, demonstrate that TNFRSF1B c.587T>G and c.*922C>T variants can serve as independent prognostic factors in CM patients.

Ansofaxine hydrochloride inhibits tumor growth and enhances Anti-TNFR2 in murine colon cancer model

Introduction: As psychoneuroimmunology flourishes, there is compelling evidence that depression suppresses the anti-tumor immune response, promotes the progression of cancer, and inhibits the effectiveness of cancer immunotherapy. Recent studies have reported that antidepressants can not only alleviate the depressant condition of cancer patients, but also strengthen the anti-tumor immunity, thus suppressing tumors. Tumor necrosis factor receptor 2 (TNFR2) antagonistic antibodies (Anti-TNFR2) targeting tumor-infiltrating regulatory T cells (Tregs) has achieved great results in preclinical studies, and with a favorable toxicity profile than existing immunotherapies, and is expected to become a new generation of more effective treatment strategies. Understanding the effects of combination therapy with antidepressants and Anti-TNFR2 may help design new strategies for cancer immunotherapy. Methods: We treated CT26, HCT116, MCA38 and SW620 colon cancer cells with fluoxetine (0-50 µM), ansofaxine hydrochloride (0-50 µM) and amitifadine hydrochloride (0-150 µM) to examine their effects on cell proliferation and apoptosis. We explored the antitumor effects of ansofaxine hydrochloride in combination with or without Anti-TNFR in subcutaneously transplanted CT26 cells in tumor-bearing mouse model. Antitumor effects were evaluated by tumor volume. NK cell, M1 macrophage cell, CD4+ T cell, CD8+ T cell, exhausted CD8+ T and regulatory T cell (Tregs) subtypes were measured by flow cytometry. 5-hydroxytryptamine, dopamine and norepinephrine levels were measured by ELISA. Results: Oral antidepression, ansofaxine hydrochloride, enhanced peripheral dopamine levels, promoted CD8+T cell proliferation, promoted intratumoral infiltration of M1 and NK cells, decreased the proportion of tumor-infiltrating exhausted CD8+T cells, and strengthened anti-tumor immunity, thereby inhibiting colon cancer growth. In combination therapy, oral administration of ansofaxine hydrochloride enhanced the efficacy of Anti-TNFR2, and produced long-term tumor control in with syngeneic colorectal tumor-bearing mice, which was attributable to the reduction in tumor-infiltrating Treg quantity and the recovery of CD8+ T cells function. Discussion: In summary, our data reveal the role of ansofaxine hydrochloride in modulating the anti-tumor immunity. Our results support that exhausted CD8+T is an important potential mechanism by which ansofaxine hydrochloride activates anti-tumor immunity and enhances anti-tumor effects of anti-TNFR2.

Identification of immune-related candidate biomarkers in plasma of patients with sporadic vestibular schwannoma

Vestibular schwannoma (VS) is an intracranial tumor arising from neoplastic Schwann cells and typically presenting with hearing loss. The traditional belief that hearing deficit is caused by physical expansion of the VS, compressing the auditory nerve, does not explain the common clinical finding that patients with small tumors can have profound hearing loss, suggesting that tumor-secreted factors could influence hearing ability in VS patients. We conducted profiling of patients' plasma for 66 immune-related factors in patients with sporadic VS (N > 170) and identified and validated candidate biomarkers associated with tumor size (S100B) and hearing (MCP-3). We further identified a nine-biomarker panel (TNR-R2, MIF, CD30, MCP-3, IL-2R, BLC, TWEAK, eotaxin, and S100B) with outstanding discriminatory ability for VS. These findings revealed possible therapeutic targets for VS, providing a unique diagnostic tool that may predict hearing change and tumor growth in VS patients, and may inform the timing of tumor resection to preserve hearing.

Tumor Necrosis Factor-Alpha and Adiponectin in Nonalcoholic Fatty Liver Disease-Associated Hepatocellular Carcinoma

Nonalcoholic fatty liver disease (NAFLD) is emerging as an important risk factor for hepatocellular carcinoma (HCC), whose prevalence is rising. Although the mechanisms of progression from NAFLD to HCC are not fully elucidated, tumor necrosis factor-α (TNF-α) and adiponectin, as well as their interplay, which seems to be antagonistic, may contribute to the pathophysiology of NAFLD-associated HCC. TNF-α initially aims to protect against hepatocarcinogenesis, but during the progression of NAFLD, TNF-α is increased, thus probably inducing hepatocarcinogenesis in the long-term, when NAFLD is not resolved. On the other hand, adiponectin, which is expected to exert anti-tumorigenic effects, is decreased during the progression of the disease, a trend that may favor hepatocarcinogenesis, but is paradoxically increased at end stage disease, i.e., cirrhosis and HCC. These observations render TNF-α and adiponectin as potentially diagnostic biomarkers and appealing therapeutic targets in the setting of NAFLD-associated HCC, possibly in combination with systematic therapy. In this regard, combination strategy, including immune checkpoint inhibitors (ICIs) with anti-TNF biologics and/or adiponectin analogs or medications that increase endogenous adiponectin, may warrant investigation against NAFLD-associated HCC. This review aims to summarize evidence on the association between TNF-α and adiponectin with NAFLD-associated HCC, based on experimental and clinical studies, and to discuss relevant potential therapeutic considerations.

Scutellarin suppresses the metastasis of triple-negative breast cancer via targeting TNFα/TNFR2-RUNX1-triggered G-CSF expression in endothelial cells

Triple-negative breast cancer (TNBC) is heterogeneous and aggressive, with high vascularity and frequent metastasis. We have already found natural flavonoid scutellarin (SC) suppressed spontaneous TNBC metastasis via normalizing tumor vasculature in vivo. In this study, supernatant from tumor necrosis factorα (TNFα)-treated human mammary microvascular endothelial cell (HMMEC) promoted cell migration and pseudopod formation in TNBC cells, but these phenomena were disappeared in SC-co-treated HMMEC. TNFα enhanced the expression of granulocyte colony-stimulating factor (G-CSF) and granulocyte-macrophage colony-stimulating factor (GM-CSF) in both HMMEC and human umbilical vein endothelial cell (HUVEC). G-CSF promoted TNBC migration and invasion in vitro, while G-CSF neutralization antibody and SC both inhibited TNBC metastasis in Balb/c mice. SC had no inhibition on the G-CSF-induced TNBC cell migration, but reduced G-CSF content in TNBC tumor tissues and TNFα-stimulated endothelial cells (ECs). SC restricted the nuclear translocation of runt-related transcription factor 1 (RUNX1) in TNBC tumor vessels and TNFα-treated ECs. RUNX1 was found to directly bind to the promoter of G-CSF in TNBC tumor vessels and regulated G-CSF expression. TNF receptor 2 (TNFR2) was crucial for regulating the TNFα-induced RUNX1 activation and G-CSF expression. Notably, SC hindered the interaction between TNFα and TNFR2 via binding to TNFR2. This work demonstrated that SC reduced TNBC metastasis by targeting TNFα/TNFR2-initiated RUNX1 activation and subsequent G-CSF production in TNBC-associated ECs.

Aberrant frequency of TNFR2-expressing CD4+ FoxP3+ regulatory T cells in nasopharyngeal carcinoma patients

TNFR2 is a surface marker of highly suppressive subset of CD4+ FoxP3+ regulatory T cells (Tregs) in humans and mice. This study examined the TNFR2 expression by Tregs of nasopharyngeal carcinoma (NPC) patients and healthy controls. The proliferation, migration, survival of TNFR2+ Tregs, and association with clinicopathological characteristics were assessed. The expression levels of selected cytokines were also determined. The results demonstrated that in both peripheral blood (PB) (10.45 ± 5.71%) and tumour microenvironment (TME) (54.38 ± 16.15%) of NPC patients, Tregs expressed TNFR2 at noticeably greater levels than conventional T cells (Tconvs) (3.91 ± 2.62%, p < 0.0001), akin to healthy controls. Expression of TNFR2 (1.06 ± 0.99%) was correlated better than CD25+ (0.40 ± 0.46%) and CD127-/low (1.00 ± 0.83% ) with FoxP3 expression in NPC PB (p = 0.0005). Though there was no significant association between TNFR2 expression with the functional capacity (proliferation, migration and survival) of Tregs (p > 0.05), the proportions of PB and TME TNFR2+ Tregs in NPC patients showed more proliferative, higher migration capacity, and better survival ability, as compared to those in healthy controls. Furthermore, TNFR2+ Tregs from NPC patients expressed significantly higher amounts of IL-6 (p = 0.0077), IL-10 (p = 0.0001), IFN-γ (p = 0.0105) and TNF-α (p < 0.0001) than those from healthy controls. Most significantly, TNFR2 expression in maximally suppressive Tregs population were linked to WHO Type III histological type, distant metastasis, progressive disease status, and poor prognosis for NPC patients. Hence, our research implies that TNFR2 expression by PB and TME Tregs may be a useful predictive indicator in NPC patients.

Role of cytokine in malignant T-cell metabolism and subsequent alternation in T-cell tumor microenvironment

T cells are an important component of adaptive immunity and T-cell-derived lymphomas are very complex due to many functional sub-types and functional elasticity of T-cells. As with other tumors, tissues specific factors are crucial in the development of T-cell lymphomas. In addition to neoplastic cells, T- cell lymphomas consist of a tumor micro-environment composed of normal cells and stroma. Numerous studies established the qualitative and quantitative differences between the tumor microenvironment and normal cell surroundings. Interaction between the various component of the tumor microenvironment is crucial since tumor cells can change the microenvironment and vice versa. In normal T-cell development, T-cells must respond to various stimulants deferentially and during these courses of adaptation. T-cells undergo various metabolic alterations. From the stage of quiescence to attention of fully active form T-cells undergoes various stage in terms of metabolic activity. Predominantly quiescent T-cells have ATP-generating metabolism while during the proliferative stage, their metabolism tilted towards the growth-promoting pathways. In addition to this, a functionally different subset of T-cells requires to activate the different metabolic pathways, and consequently, this regulation of the metabolic pathway control activation and function of T-cells. So, it is obvious that dynamic, and well-regulated metabolic pathways are important for the normal functioning of T-cells and their interaction with the microenvironment. There are various cell signaling mechanisms of metabolism are involved in this regulation and more and more studies have suggested the involvement of additional signaling in the development of the overall metabolic phenotype of T cells. These important signaling mediators include cytokines and hormones. The impact and role of these mediators especially the cytokines on the interplay between T-cell metabolism and the interaction of T-cells with their micro-environments in the context of T-cells lymphomas are discussed in this review article.

Exploring the crosstalk between endothelial cells, immune cells, and immune checkpoints in the tumor microenvironment: new insights and therapeutic implications

The tumor microenvironment (TME) is a highly intricate milieu, comprising a multitude of components, including immune cells and stromal cells, that exert a profound influence on tumor initiation and progression. Within the TME, angiogenesis is predominantly orchestrated by endothelial cells (ECs), which foster the proliferation and metastasis of malignant cells. The interplay between tumor and immune cells with ECs is complex and can either bolster or hinder the immune system. Thus, a comprehensive understanding of the intricate crosstalk between ECs and immune cells is essential to advance the development of immunotherapeutic interventions. Despite recent progress, the underlying molecular mechanisms that govern the interplay between ECs and immune cells remain elusive. Nevertheless, the immunomodulatory function of ECs has emerged as a pivotal determinant of the immune response. In light of this, the study of the relationship between ECs and immune checkpoints has garnered considerable attention in the field of immunotherapy. By targeting specific molecular pathways and signaling molecules associated with ECs in the TME, novel immunotherapeutic strategies may be devised to enhance the efficacy of current treatments. In this vein, we sought to elucidate the relationship between ECs, immune cells, and immune checkpoints in the TME, with the ultimate goal of identifying novel therapeutic targets and charting new avenues for immunotherapy.

Single-cell transcriptomics identify TNFRSF1B as a novel T-cell exhaustion marker for ovarian cancer

BACKGROUND

Ovarian cancer (OC) patients routinely show poor immunotherapeutic response due to the complex tumour microenvironment (TME). It is urgent to explore new immunotherapeutic markers.

METHODS

Through the single-cell RNA sequencing (scRNA-seq) analyses on high-grade serous OC (HGSOC), moderate severity borderline tumour and matched normal ovary, we identified a novel exhausted T cells subpopulation that related to poor prognosis in OC. Histological staining, multiple immunofluorescences, and flow cytometry were applied to validate some results from scRNA-seq. Furthermore, a tumour-bearing mice model was constructed to investigate the effects of TNFRSF1B treatment on tumour growth in vivo.

RESULTS

Highly immunosuppressive TME in HGSOC is displayed compared to moderate severity borderline tumour and matched normal ovary. Subsequently, a novel exhausted subpopulation of CD8+ TNFRSF1B+ T cells is identified, which is associated with poor survival. In vitro experiments demonstrate that TNFRSF1B is specifically upregulated on activated CD8+ T cells and suppressed interferon-γ secretion. The expression of TNFRSF1B on CD8+ T cells is closely related to OC clinical malignancy and is a marker of poor prognosis through 140 OC patients' verification. In addition, the blockade of TNFRSF1B inhibits tumour growth via profoundly remodeling the immune microenvironment in the OC mouse model.

CONCLUSIONS

Our transcriptomic results analyzed by scRNA-seq delineate a high-resolution snapshot of the entire tumour ecosystem of OC TME. The major applications of our findings were an exhausted subpopulation of CD8+ TNFRSF1B+ T cells for predicting OC patient prognosis and the potential therapeutic value of TNFRSF1B. These findings demonstrated the clinical value of TNFRSF1B as a potential immunotherapy target and extended our understanding of factors contributing to immunotherapy failure in OC.

TNFR2 promotes pancreatic cancer proliferation, migration, and invasion via the NF-κB signaling pathway

PURPOSE

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive malignant disease with low overall survival; chemotherapy and immunotherapy have limited efficacy. Tumor necrosis factor receptor 2 (TNFR2), a type II transmembrane protein, contributes to the development and progression of several tumors. In this study, we elucidated the effect and molecular mechanisms of TNFR2.

METHOD

We used The Cancer Genome Atlas and the Genotype-Tissue Expression database to compare the expression of the TNFR2 gene between normal and malignant pancreatic tissue. Using immunohistochemical staining, we divided the patients into high and low-expression groups, then investigated clinicopathologic data and survival curves of pancreatic cancer patients. We measured TNFR2 protein expression in PANC-1 and ASPC-1 pancreatic cancer cells subjected to TNFR2 small interfering RNA or negative control treatment. We performed proliferation, invasion, and migration assays to study the biological effects of TNFR2 in PDAC. The molecular mechanisms were validated using western blotting.

RESULTS

TNFR2 was more highly expressed in PDAC cells and tissues than controls. Abundant expression of TNFR2 was associated with aggressive clinicopathologic characteristics and poor outcomes. Overexpression of TNFR2 promoted PDAC cell proliferation, migration, and invasion in vitro. Mechanistically, TNFR2 binds to TNF-α and activates the NF-κB signaling pathway.

CONCLUSION

TNFR2 is a prognostic marker that facilitates the proliferation, migration, and invasion of PDAC via the NF-κB signaling pathway. TNFR2 may become a therapeutic target.

The copper chelator ammonium tetrathiomolybdate inhibits the progression of experimental endometriosis in TNFR1-deficient mice

The TNF-α/TNFR system is involved in endometriosis (EDT), a gynecologic estrogen-dependent disease. Elevated copper concentrations have also been associated with EDT, even in TNFR1-deficient mice where disease worsening occurs. We aimed to evaluate whether treatment with ammonium tetrathiomolybdate (TM, copper chelator) is beneficial in TNFR1-deficient mice presenting with worsened EDT status. Female C57BL/6 mice were divided into three groups: KO Sham, KO EDT, and KO EDT+TM. TM was administered from the 15th postoperative day, and samples were collected one month after inducing pathology. In peritoneal fluid, copper and estradiol levels were determined by electrothermal atomic absorption spectrometry and electrochemiluminescence, respectively. Lesions were processed for the analysis of cell proliferation (PCNA immunohistochemistry), expression of angiogenic markers (RT-qPCR), and oxidative stress (spectrophotometric methods). We found that EDT increased copper and estradiol levels compared to the KO Sham group, while the TM administration restored the levels of both factors. TM also reduced the volume and weight of the lesions and cell proliferation rate. Besides, TM treatment decreased the number of blood vessels and the Vegfa, Fgf2, and Pdgfb expression. Furthermore, superoxide dismutase and catalase activity decreased, and lipid peroxidation increased. TM administration inhibits EDT progression in TNFR1-deficient mice where the pathology is exacerbated.

Sequential treatment with a TNFR2 agonist and a TNFR1 antagonist improves outcomes in a humanized mouse model for MS

TNF signaling is an essential regulator of cellular homeostasis. Through its two receptors TNFR1 and TNFR2, soluble versus membrane-bound TNF enable cell death or survival in a variety of cell types. TNF-TNFRs signaling orchestrates important biological functions such as inflammation, neuronal activity as well as tissue de- and regeneration. TNF-TNFRs signaling is a therapeutic target for neurodegenerative diseases such as multiple sclerosis (MS) and Alzheimer's disease (AD), but animal and clinical studies yielded conflicting findings. Here, we ask whether a sequential modulation of TNFR1 and TNFR2 signaling is beneficial in experimental autoimmune encephalomyelitis (EAE), an experimental mouse model that recapitulates inflammatory and demyelinating aspects of MS. To this end, human TNFR1 antagonist and TNFR2 agonist were administered peripherally at different stages of disease development in TNFR-humanized mice. We found that stimulating TNFR2 before onset of symptoms leads to improved response to anti-TNFR1 therapeutic treatment. This sequential treatment was more effective in decreasing paralysis symptoms and demyelination, when compared to single treatments. Interestingly, the frequency of the different immune cell subsets is unaffected by TNFR modulation. Nevertheless, treatment with only a TNFR1 antagonist increases T-cell infiltration in the central nervous system (CNS) and B-cell cuffing at the perivascular sites, whereas a TNFR2 agonist promotes Treg CNS accumulation. Our findings highlight the complicated nature of TNF signaling which requires a timely balance of selective activation and inhibition of TNFRs in order to exert therapeutic effects in the context of CNS autoimmunity.

Anti-TNFR2 enhanced the antitumor activity of a new HMGN1/3M-052 stimulated dendritic cell vaccine in a mouse model of colon cancer

Immunotherapy is the new approach for cancer treatment that can be achieved through several strategies, one of which is dendritic cells (DCs) vaccine therapy. However, traditional DC vaccination lacks accurate targeting, so DC vaccine preparation needs to be optimized. Immunosuppressive CD4⁺Foxp3⁺ regulatory T cells (Tregs) in the tumor microenvironment can promote tumor immune escape. Therefore, targeting Tregs has become a strategy for tumor immunotherapy. In this study, we found that HMGN1 (N1, a dendritic cell-activating TLR4 agonist) and 3M-052 (a newly synthesized TLR7/8 agonist) synergistically stimulate DCs maturation and increase the production of proinflammatory cytokines TNFα and IL-12. In a colon cancer mice model, vaccination with N1 and 3M-052 stimulated and tumor antigen-loaded DCs combined with anti-TNFR2 inhibited tumor growth in mice, and the antitumor effect was mainly achieved through stimulation of cytotoxic CD8 T cell activation and depletion of Tregs. Overall, the combinating of DC activation by N1 and 3M-052 with inhibition of Tregs by antagonizing TNFR2 as a therapeutic strategy may represent a more effective strategy for cancer treatment.

Tregs dysfunction aggravates postoperative cognitive impairment in aged mice

OBJECTIVES

Enhanced neuroinflammation is an important mechanism underlying perioperative neurocognitive disorders. Regulatory T cells (Tregs) play a crucial role in regulating systemic immune responses. The present study was aimed to investigate the participation of Tregs in the development of postoperative cognitive dysfunction (POCD).

METHODS

Surgery-associated neurocognitive disorder was induced in 18-month-old mice subjected to internal fixation of tibial fracture. Morris water maze was used to examine mice cognitive function. Splenic Tregs were collected for RNA sequencing and flow cytometry. Levels of inflammatory factors in the circulation and hippocampus were measured by enzyme-linked immunosorbent assay. Protein presences of tight junction proteins were detected by immunofluorescence.

RESULTS

Surgery of internal fixation of tibial fracture induced cognitive impairment in aged mice, accompanied by elevated plasma levels of inflammatory factors and increased circulating Tregs. Transfusion of Tregs from young mice partially restored the structure of the blood-brain barrier and alleviated POCD in aged mice. Compared with young Tregs, differentially expressed genes in aged Tregs were enriched in tumor necrosis factor (TNF) signaling pathway and cytokine-cytokine receptor interaction. Flow cytometry revealed that aged Tregs had blunted functions under basal and stimulated conditions. Blockade of the CD25 epitope protected the blood-brain barrier structure, reduced TNF-α levels in the hippocampus, and improved surgery-associated cognition in aged mice.

CONCLUSIONS

Blocking peripheral regulatory T cells improves surgery-induced cognitive function in aged mice. Therefore, aged Tregs play an essential role in the occurrence of POCD.

Association of DNA Promoter Methylation and BRAF Mutation in Thyroid Cancer

The BRAF V600E mutation and DNA promoter methylation play important roles in the pathogenesis of thyroid cancer (TC). However, the association of these genetic and epigenetic alterations is not clear. In this study, using paired tumor and surrounding normal tissue from the same patients, on a genome-wide scale we tried to identify (a) any association between BRAF mutation and DNA promoter methylation, and (b) if the molecular findings may provide a basis for therapeutic intervention. We included 40 patients with TC (female = 28, male = 12) without distant metastasis. BRAF mutation was present in 18 cases. We identified groups of differentially methylated loci (DML) that are found in (a) both BRAF mutant and wild type, (b) only in BRAF mutant tumors, and (c) only in BRAF wild type. BRAF mutation-specific promoter loci were more frequently hypomethylated, whereas BRAF wild-type-specific loci were more frequently hypermethylated. Common DML were enriched in cancer-related pathways, including the mismatch repair pathway and Wnt-signaling pathway. Wild-type-specific DML were enriched in RAS signaling. Methylation status of checkpoint signaling genes, as well as the T-cell inflamed genes, indicated an opportunity for the potential use of PDL1 inhibitors in BRAF mutant TC. Our study shows an association between BRAF mutation and methylation in TC that may have biological significance.

TNFR2 antagonistic antibody induces the death of tumor infiltrating CD4+Foxp3+ regulatory T cells

BACKGROUND

TNFR2 expression is a characteristic of highly potent immunosuppressive tumor infiltrating CD4⁺Foxp3⁺ regulatory T cells (Tregs). There is compelling evidence that TNF through TNFR2 preferentially stimulates the activation and expansion of Tregs. We and others, therefore, proposed that targeting TNFR2 may provide a novel strategy in cancer immunotherapy. Several studies have shown the effect of TNFR2 antagonistic antibodies in different tumor models. However, the exact action of the TNFR2 antibody on Tregs remained understood.

METHOD

TY101, an anti-murine TNFR2 antibody, was used to examine the effect of TNFR2 blockade on Treg proliferation and viability in vitro. The role of TNFR2 on Treg viability was further validated by TNFR2 knockout mice and in the TY101 antagonistic antibody-treated mouse tumor model.

RESULTS

In this study, we found that an anti-mouse TNFR2 antibody TY101 could inhibit TNF-induced proliferative expansion of Tregs, indicative of an antagonistic property. To examine the effect of TY101 antagonistic antibody on Treg viability, we treated unfractionated lymph node (L.N.) cells with Dexamethasone (Dex) which was known to induce T cell death. The result showed that TY101 antagonistic antibody treatment further promoted Treg death in the presence of Dex. This led us to find that TNFR2 expression was crucial for the survival of Tregs. In the mouse EG7 lymphoma model, treatment with TY101 antagonistic antibody potently inhibited tumor growth, resulting in complete regression of the tumor in 60% of mice. The treatment with TY101 antagonistic antibody elicited potent antitumor immune responses in this model, accompanied by enhanced death of Tregs.

CONCLUSION

This study, therefore, provides clear experimental evidence that TNFR2 antagonistic antibody, TY101, can promote the death of Tregs, and this effect may be attributable to the antitumor effect of TNFR2 antagonistic antibody.

Combining TNFR2-Expressing Tregs and IL-6 as Superior Diagnostic Biomarkers for High-Grade Serous Ovarian Cancer Masses

We hypothesised that the inclusion of immunosuppressive and inflammatory biomarkers in HGSOC patients would improve the sensitivity and specificity of the preoperative marker prediction of malignancy in patients with ovarian masses. We tested a panel of 29 soluble immune factors by multiplex bead immunoassay and 16 phenotypic T cell markers by flow cytometry in pre-treatment blood samples from 66 patients undergoing surgery for suspected ovarian cancer or ovarian cancer risk reduction. The potential diagnostic utility of all parameters was explored using Volcano plots, principal component analysis (PCA) and receiver operator characteristic (ROC) analysis. We also assessed the effect of culturing PBMCs from 20 healthy donors in the presence of malignant ascites fluid. The combination of TNFR2+ Tregs and IL-6 in the pre-treatment blood of patients with advanced HGSOC effectively discriminated patients with benign or malignant ovarian masses. In vitro culturing of the PBMCs of healthy donors in malignant ascites promoted an increase in TNFR2-expressing Tregs, which were decreased following blockade with IL-6 or STAT3 activity. Pre-treatment serum IL-6 and peripheral blood TNFR2+ Tregs may be potential clinical biomarkers that can discriminate patients with malignant compared to benign ovarian cancer masses, and the relationship between IL-6 and TNFR2+ Treg is likely to be mediated via the STAT3 signalling pathway.

Distepharinamide, a novel dimeric proaporphine alkaloid from Diploclisia glaucescens, inhibits the differentiation and proliferative expansion of CD4+Foxp3+ regulatory T cells

BACKGROUND

CD4⁺Foxp3⁺ regulatory T cells (Tregs) represent the primary cellular mechanism of tumor immune evasion. Elimination of Treg activity by the pharmacological agent may enhance anti-tumor immune responses. However, Treg-eliminating agents, especially those with small molecules, are rarely reported.

PURPOSE

To identify small molecule inhibitors of Treg cells from natural products.

METHODS

Compounds from Diploclisia glaucescens were isolated by column chromatography, and structures were identified by spectroscopic evidence and quantum calculations. The tet-On system for Foxp3-GFP expression in Jurkat T cells was generated to screen Treg inhibitors based on Foxp3 expression. The effect of the compound on TNF-induced proliferative expansion of naturally occurring Tregs (nTregs) and TGF-β-induced generation of Tregs (iTregs) from naive CD4⁺ Tcells was further examined.

RESULTS

A novel dimeric proaporphine alkaloid, designated as distepharinamide (DSA) with a symmetric structure isolated from the stems of D. glaucescens, restrained the doxycycline (Doxy)-induced Foxp3-tGFP expression, decreased the half-life of Foxp3 mRNA as well as reduced the mRNA levels of chemokine receptors (CCR4, CCR8 and CCR10) in Jurkat T cells with inducible Foxp3-tGFP expression. In lymphocytes or purified Tregs from wild-type C57BL/6 mice or from C57BL/6-Tg(Foxp3-DTR/EGFP)23.2Spar/Mmjax mice, DSA markedly inhibited TNF-induced proliferative expansion of Tregs present in the unfractionated CD4⁺ T cells, accompanied by the down-regulation of TNFR2, CD25 and CTLA4 expression on Tregs. Furthermore, DSA potently inhibited TGF-β-induced differentiation of Foxp3-expressing iTregs. Importantly, the expression of Foxp3 mRNA by both nTregs and iTregs was decreased by DSA treatment. Nevertheless, DSA at the same concentrations did not inhibit the proliferation of conventional CD4⁺ and CD8⁺ T cells stimulated by anti-CD3/CD28 antibodies.

CONCLUSION

DSA, a novel dimeric proaporphine alkaloid, potently inhibited the expansion of nTregs and generation of iTregs. Therefore, DSA or its analogs may merit further investigation as novel immunotherapeutic agents.

Elevation of circulating TNF receptor 2 in cancer: A systematic meta-analysis for its potential as a diagnostic cancer biomarker

High Tumor Necrosis Factor Receptor 2 (TNFR2) expression is characteristic of diverse malignant cells during tumorigenesis. The protein is also expressed by many immunosuppressive cells during cancer development, allowing cancer immune escape. A growing body of evidence further suggests a correlation between the circulating form of this protein and cancer development. Here we conducted a systematic meta-analysis of cancer studies published up until 1st October 2022, in which the circulating soluble TNFR2 (sTNFR2) concentrations in patients with cancers were recorded and their association with cancer risk was assessed. Of the 14,615 identified articles, 44 studies provided data on the correlation between cancer risk and the level of circulating sTNFR2. The pooled means comparison showed a consistently significant increase in the levels of sTNFR2 in diverse cancers when compared to healthy controls. These included colorectal cancer, ovarian cancer, breast cancer, non-Hodgkin's lymphoma, Hodgkin's lymphoma, lung cancer, hepatocarcinoma, and glioblastoma. In a random-effect meta-analysis, the cancer-specific odd ratios (OR) showed significant correlations between increased circulating sTNFR2 levels and the risk of colorectal cancer, non-Hodgkin's lymphoma, and hepatocarcinoma at 1.59 (95% CI:1.20-2.11), 1.98 (95% CI:1.49-2.64) and 4.32 (95% CI:2.25-8.31) respectively. The overall result showed an association between circulating levels of sTNFR2 and the risk of developing cancer at 1.76 (95% CI:1.53-2.02). This meta-analysis supports sTNFR2 as a potential diagnostic biomarker for cancer, albeit with different predictive strengths for different cancer types. This is consistent with a potential key role for TNFR2 involvement in cancer development.

Scutellarin suppresses triple-negative breast cancer metastasis by inhibiting TNFα-induced vascular endothelial barrier breakdown

Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer with high vascularity and frequent metastasis. Tumor-associated abnormal vasculature was reported to accelerate TNBC metastasis. Scutellarin (SC) is a natural flavonoid with a cardiovascular protective function. In this study, SC reduced TNBC metastasis and alleviated tumor-associated vascular endothelial barrier injury in vivo. SC rescued the tumor necrosis factor-α (TNFα)-induced diminishment of endothelial junctional proteins and dysfunction of the endothelial barrier in vitro. SC reduced the increased transendothelial migration of TNBC cells through a monolayer composed of TNFα-stimulated human mammary microvascular endothelial cells (HMMECs) or human umbilical vein endothelial cells (HUVECs). TNFα induced the nuclear translocation of enhancer of zeste homolog-2 (EZH2), and its chemical inhibitor GSK126 blocked TNFα-induced endothelial barrier disruption and subsequent TNBC transendothelial migration. TNF receptor 2 (TNFR2) is the main receptor by which TNFα regulates endothelial barrier breakdown. Extracellular signal-regulated protein kinase (ERK)1/2 was found to be downstream of TNFα/TNFR2 and upstream of EZH2. Additionally, SC abrogated the TNFR2-ERK1/2-EZH2 signaling axis both in vivo and in vitro. Our results suggest that SC reduced TNBC metastasis by suppressing TNFα-initiated vascular endothelial barrier breakdown through rescuing the reduced expression of junctional proteins by regulating the TNFR2-ERK1/2-EZH2 signaling pathway.

TNFR2 antagonist and agonist: a potential therapeutics in cancer immunotherapy

Tumour necrosis factor receptor 2 or TNFR2 is considered an appealing target protein due to its limited frequency to TREGs, which are highly immunosuppressive and present on human malignancies. Numerous studies have revealed that TNFR2 is primarily found on MDSCs (myeloid-derived suppressor cells) and CD + Foxp3 + regulatory T cells (TREGs). Therefore, it has great importance in the proliferation and functional activity of TREGs and MDSCs. TNFR2 suppression must be downregulated or upregulated as required to treat malignancies and diseases like autoimmune disorders. Therefore, at the molecular level, advances in the comprehension of TNFR2's complex structure and its binding to TNF have opened the door to structure-guided drug development. Two critical obstacles to cancer treatment are the dearth of TREG-specific inhibitors and the lack of widely applicable ways to target tumours via frequently expressed surface oncogenes directly. Many researchers have discovered potential antagonists and agonists of TNFR2, which were successful in inhibiting TREGs proliferation, reducing soluble TNFR2 secretion from normal cells, and expanding T effector cells. The data represented in the following review article elucidates the clinically administrated TNFR2 antagonist and agonist in treating cancers.

A novel necroptosis-related gene signature associated with immune landscape for predicting the prognosis of papillary thyroid cancer

Background: Necroptosis, a type of programmed cell death, has been implicated in a variety of cancer-related biological processes. However, the roles of necroptosis-related genes in thyroid cancer yet remain unknown.

Methods: A necroptosis-related gene signature was constructed using the least absolute shrinkage and selection operator (LASSO) regression analysis and Cox regression analysis. The predictive value of the prognostic signature was validated in an internal cohort. Additionally, the single-sample gene set enrichment analysis (ssGSEA) was used to examine the relationships between necroptosis and immune cells, immunological functions, and immune checkpoints. Next, the modeled genes expressions were validated in 96 pairs of clinical tumor and normal tissue samples. Finally, the effects of modeled genes on PTC cells were studied by RNA interference approaches in vitro.

Results: In this study, the risk signature of seven necroptosis-related genes was created to predict the prognosis of papillary thyroid cancer (PTC) patients, and all patients were divided into high- and low-risk groups. Patients in the high-risk group fared worse in terms of overall survival than those in the low-risk group. The area under the curve (AUC) of the receiving operating characteristic (ROC) curves proved the predictive capability of created signature. The risk score was found to be an independent risk factor for prognosis in multivariate Cox analysis. The low-risk group showed increased immune cell infiltration and immunological activity, implying that they might respond better to immune checkpoint inhibitor medication. Next, GEO database and qRT-PCR in 96 pairs of matched tumorous and non-tumorous tissues were used to validate the expression of the seven modeled genes in PTCs, and the results were compatible with TCGA database. Finally, overexpression of IPMK, KLF9, SPATA2 could significantly inhibit the proliferation, invasion and migration of PTC cells.

Conclusion: The created necroptosis associated risk signature has the potential to have prognostic capability in PTC for patient outcome. The findings of this study could pave the way for further research into the link between necroptosis and tumor immunotherapy.

IP6 reduces colorectal cancer metastasis by mediating the interaction of gut microbiota with host genes

Inositol hexaphosphate (IP6) is a phytochemical widely found in grains and legumes that plays an anti-cancer role. However, the mechanism underlying the inhibition of colorectal cancer metastasis by IP6 through host genes, gut microbiota, and their interactions remain elusive. In this study, 16S rRNA sequencing was used to study the effect of IP6 on gut microbiota in an orthotopic transplantation model of colorectal cancer mice. The transcriptome was used to study the changes of host genes in metastasis and the relationship with gut microbiota. The results showed that the gut microbiota composition of model mice was significantly different from that of normal mice. The beta diversity partly tended to return to the normal level after IP6 intervention. Especially, Lactobacillus helveticus and Lactococcus lactis were recovered after IP6-treated. Enrichment analysis showed that the enrichment score of the Cytokine-Cytokine receptor interaction signal pathway decreased after IP6 treatment compared to the model group. Further analysis of differentially expressed genes (DEGs) in this pathway showed that IP6 reduced the expression of the Tnfrsf1b gene related to the area of liver metastasis, and the Tnfrsf1b gene was negatively correlated with the relative abundance of Lactobacillus helveticus. Our results presented that host gene, microbiome and their interaction may serve as promising targets for the mechanism of IP6 intervention in colorectal cancer metastasis.

Scutellarin enhances anti-tumor immune responses by reducing TNFR2-expressing CD4+Foxp3+ regulatory T cells

One characteristic of tumor-associated CD4⁺Foxp3⁺ regulatory T cells (Tregs) is the high expression of tumor necrosis factor receptor type II (TNFR2), a receptor that mediates the decisive effect of tumor necrosis factor (TNF) in the activation and expansion of Tregs. There is increasing evidence that inhibition of TNFR2 can enhance anti-tumor immune responses. Therefore, we screened Chinese herbal extracts for their capacity to block TNF-TNFR2 interaction. The results showed that the treatment with a Chinese herb extract could inhibit TNFR2-induced biological responses in vitro, including the proliferation of TNFR2⁺ Tregs. Our subsequent study led to the identification of flavonoid compound scutellarin was responsible for the activity. Our results showed that scutellarin is able to disrupt the interaction of TNF-TNFR2 and inhibited the phosphorylation of p38 MAPK, a down-stream signaling component of TNFR2. Importantly, in vivo scutellarin treatment markedly enhanced the efficacy of tumor immunotherapy with CpG oligodeoxynucleotide in mouse CT26 colon cancer model. This effect of scutellarin was associated with the reduction of the number of tumor-infiltrating TNFR2-expressing Tregs and increased tumor infiltration of interferon-γ-producing CD8⁺ T cells. Our result also suggests that scutellarin or its analogs may be used as an adjuvant to enhance the anti-tumor effect of immunotherapeutic agent by eliminating TNFR2⁺ Treg activity.

TNFR2 Costimulation Differentially Impacts Regulatory and Conventional CD4+ T-Cell Metabolism

CD4+ conventional T cells (Tconvs) mediate adaptive immune responses, whereas regulatory T cells (Tregs) suppress those responses to safeguard the body from autoimmunity and inflammatory diseases. The opposing activities of Tconvs and Tregs depend on the stage of the immune response and their environment, with an orchestrating role for cytokine- and costimulatory receptors. Nutrient availability also impacts T-cell functionality via metabolic and biosynthetic processes that are largely unexplored. Many data argue that costimulation by Tumor Necrosis Factor Receptor 2 (TNFR2) favors support of Treg over Tconv responses and therefore TNFR2 is a key clinical target. Here, we review the pertinent literature on this topic and highlight the newly identified role of TNFR2 as a metabolic regulator for thymus-derived (t)Tregs. We present novel transcriptomic and metabolomic data that show the differential impact of TNFR2 on Tconv and tTreg gene expression and reveal distinct metabolic impact on both cell types.

The Roles of TNFR2 Signaling in Cancer Cells and the Tumor Microenvironment and the Potency of TNFR2 Targeted Therapy

The appreciation that cancer growth is promoted by a dynamic tumor microenvironment (TME) has spawned novel approaches to cancer treatment. New therapies include agents that activate quiescent T effector cells and agents that interfere with abnormal neovascularity. Although promising, many experimental therapies targeted at the TME have systemic toxicity. Another approach is to target the TME with greater specificity by taking aim at the tumor necrosis factor receptor 2 (TNFR2) signaling pathway. TNFR2 is an attractive molecular target because it is rarely expressed in normal tissues (thus, has low potential for systemic toxicity) and because it is overexpressed on many types of cancer cells as well as on associated TME components, such as T regulatory cells (Tregs), tumor-associated macrophages, and other cells that facilitate tumor progression and spread. Novel therapies that block TNFR2 signaling show promise in cell culture studies, animal models, and human studies. Novel antibodies have been developed that expressly kill only rapidly proliferating cells expressing newly synthesized TNFR2 protein. This review traces the origins of our understanding of TNFR2's multifaceted roles in the TME and discusses the therapeutic potential of agents designed to block TNFR2 as the cornerstone of a TME-specific strategy.

The Roles of TNFR2 Signaling in Cancer Cells and the Tumor Microenvironment and the Potency of TNFR2 Targeted Therapy

The appreciation that cancer growth is promoted by a dynamic tumor microenvironment (TME) has spawned novel approaches to cancer treatment. New therapies include agents that activate quiescent T effector cells and agents that interfere with abnormal neovascularity. Although promising, many experimental therapies targeted at the TME have systemic toxicity. Another approach is to target the TME with greater specificity by taking aim at the tumor necrosis factor receptor 2 (TNFR2) signaling pathway. TNFR2 is an attractive molecular target because it is rarely expressed in normal tissues (thus, has low potential for systemic toxicity) and because it is overexpressed on many types of cancer cells as well as on associated TME components, such as T regulatory cells (Tregs), tumor-associated macrophages, and other cells that facilitate tumor progression and spread. Novel therapies that block TNFR2 signaling show promise in cell culture studies, animal models, and human studies. Novel antibodies have been developed that expressly kill only rapidly proliferating cells expressing newly synthesized TNFR2 protein. This review traces the origins of our understanding of TNFR2’s multifaceted roles in the TME and discusses the therapeutic potential of agents designed to block TNFR2 as the cornerstone of a TME-specific strategy.

Different subpopulations of regulatory T cells in human autoimmune disease, transplantation, and tumor immunity

CD4⁺CD25⁺ regulatory T cells (Tregs), a subpopulation of naturally CD4⁺ T cells that characteristically express transcription factor Forkhead box P3 (FOXP3), play a pivotal role in the maintenance of immune homeostasis and the prevention of autoimmunity. With the development of biological technology, the understanding of plasticity and stability of Tregs has been further developed. Recent studies have suggested that human Tregs are functionally and phenotypically diverse. The functions and mechanisms of different phenotypes of Tregs in different disease settings, such as tumor microenvironment, autoimmune diseases, and transplantation, have gradually become hot spots of immunology research that arouse extensive attention. Among the complex functions, CD4⁺CD25⁺FOXP3⁺ Tregs possess a potent immunosuppressive capacity and can produce various cytokines, such as IL‐2, IL‐10, and TGF‐β, to regulate immune homeostasis. They can alleviate the progression of diseases by resisting inflammatory immune responses, whereas promoting the poor prognosis of diseases by helping cells evade immune surveillance or suppressing effector T cells activity. Therefore, methods for targeting Tregs to regulate their functions in the immune microenvironment, such as depleting them to strengthen tumor immunity or expanding them to treat immunological diseases, need to be developed. Here, we discuss that different subpopulations of Tregs are essential for the development of immunotherapeutic strategies involving Tregs in human diseases.

Targeting TNFR2: A Novel Breakthrough in the Treatment of Cancer

Tumor necrosis factor (TNF) receptor type II (TNFR2) is expressed in various tumor cells and some immune cells, such as regulatory T cells and myeloid-derived suppressing cells. TNFR2 contributes a lot to the tumor microenvironment. For example, it directly promotes the occurrence and growth of some tumor cells, activates immunosuppressive cells, and supports immune escape. Existing studies have proved the importance of TNFR2 in cancer treatment. Here, we reviewed the activation mechanism of TNFR2 and its role in signal transduction in the tumor microenvironment. We summarized the expression and function of TNFR2 within different immune cells and the potential opportunities and challenges of targeting TNFR2 in immunotherapy. Finally, the advantages and limitations of TNFR2 to treat tumor-related diseases are discussed, and the problems that may be encountered in the clinical development and application of targeted anti-TNFR2 agonists and inhibitors are analyzed.

Elevation of the Plasma Levels of TNF Receptor 2 in Association with Those of CD25, OX40, and IL-10 and HTLV-1 Proviral Load in Acute Adult T-Cell Leukemia

Adult T-cell leukemia/lymphoma (ATL) cells express TNF receptor type-2 (TNFR2) on their surface and shed its soluble form (sTNFR2). We previously reported that sTNFR2 levels were highly elevated in the plasma of patients with acute ATL. To investigate whether its quantitation would be helpful for the diagnosis or prediction of the onset of acute ATL, we examined the plasma levels of sTNFR2 in a large number of specimens obtained from a cohort of ATL patients and asymptomatic human T-cell leukemia virus type 1 (HTLV-1) carriers (ACs) and compared them to those of other candidate ATL biomarkers (sCD25, sOX40, and IL-10) by enzyme-linked immunosorbent assays (ELISA) and HTLV-1 proviral loads. We observed that sTNFR2 levels were significantly elevated in acute ATL patients compared to ACs and patients with other types of ATL (chronic, smoldering, and lymphoma). Importantly, sTNFR2 levels were significantly correlated with those of sCD25, sOX40, and IL-10, as well as proviral loads. Thus, the present study confirmed that an increase in plasma sTNFR2 levels is a biomarker for the diagnosis of acute ATL. Examination of plasma sTNFR2 alone or in combination with other ATL biomarkers may be helpful for the diagnosis of acute ATL.

Antagonistic Antibody Targeting TNFR2 Inhibits Regulatory T Cell Function to Promote Anti-Tumor Activity

Infiltration of regulatory T cells (Tregs) in the tumor microenvironment suppresses anti-tumor immune response, and promotes tumor progression. Tumor necrosis factor receptor-2 (TNFR2), which is highly expressed on Tregs, activates Tregs through nuclear factor kappa B (NF-κB) pathway. Moreover, TNFR2⁺ Tregs have been shown to be most suppressive among all Tregs populations in tumor. Due to the unique expression pattern and function of TNFR2 on Tregs, a TNFR2 blocking antibody is expected to compromise Tregs function, relieve Tregs-mediated immunosuppression, and hence to enhance anti-tumor immune response. AN3025 is an antagonistic anti-human TNFR2 (hTNFR2) antibody that is currently under preclinical development. This study investigates the immunomodulatory and anti-tumor activity of AN3025. AN3025 was generated through rabbit immunization with extracellular domain of human TNFR2 and subsequent humanization by complementarity-determining regions (CDRs) grafting. AN3025 binds to the extracellular domain of both human and cynomolgus with sub-nanomolar affinity and specificity, but not mouse or rat TNFR2. AN3025 inhibited tumor necrosis factor alpha (TNFα) induced cell death of hTNFR2-overexpressing Jurkat cells by competing with TNFα for binding to hTNFR2. In the Tregs/T effector co-culture assay, AN3025 increased T effector proliferation and enhanced interferon gamma (IFNγ) production. As a monotherapy, AN3025 significantly inhibited MC38 tumor growth in TNFR2 humanized mouse model. Subsequent flow cytometry (FACS) and immunohistochemistry (IHC) analysis revealed that administration of AN3025 led to decreased Tregs population, increased CD4⁺ and CD8⁺ T cell numbers in the tumor. The anti-tumor activity of AN3025 was dependent on the existence of CD4⁺ and CD8⁺ T cells, as depletion of CD4⁺ and CD8⁺ T cells abolished the anti-tumor activity of AN3025. In addition, AN3025 in combination with anti-PD-1 antibody demonstrated stronger in-vivo anti-tumor activity. The potent anti-tumor efficacy of AN3025, either as a monotherapy or in combination with anti-PD-1 antibody, supports its further clinical development for the treatment of various human tumors.

Combination cancer immunotherapy targeting TNFR2 and PD-1/PD-L1 signaling reduces immunosuppressive effects in the microenvironment of pancreatic tumors

BACKGROUNDS

In advanced pancreatic ductal adenocarcinoma (PDAC), immune therapy, including immune checkpoint inhibitors, has limited efficacy, encouraging the study of combination therapy.

METHODS

Tumor necrosis factor receptor 2 (TNFR2) was analyzed via immunohistochemistry, immunofluorescence, western blotting, and ELISAs. The in vitro mechanism that TNFR2 regulates programmed cell death 1 ligand 1 (PD-L1) was investigated using immunofluorescence, immunohistochemistry, flow cytometry, western blotting, and chromatin immunoprecipitation (ChIP). In vivo efficacy and mechanistic studies, using C57BL/6 mice and nude mice with KPC cell-derived subcutaneous and orthotopic tumors, employed antibodies against TNFR2 and PD-L1. Survival curves were constructed for the orthotopic model and a genetically engineered PDAC model (LSL-KrasG12D/+; LSL-Trp53R172H/+; Pdx1-Cre). Mass cytometry, immunohistochemistry, and flow cytometry analyzed local and systemic alterations in the immunophenotype.

RESULTS

TNFR2 showed high expression and is a prognostic factor in CD8+ T cell-enriched pancreatic cancer. TNFR2 promotes tumorigenesis and progression of pancreatic cancer via dual effect: suppressing cancer immunogenicity and partially accelerating tumor growth. TNFR2 positivity correlated with PD-L1, and in vitro and in vivo, it could regulate the expression of PDL1 at the transcription level via the p65 NF-κB pathway. Combining anti-TNFR2 and PD-L1 antibodies eradicated tumors, prolonged overall survival in pancreatic cancer, and induced strong antitumor immune memory and secondary prevention by reducing the infiltration of Tregs and tumor-associated macrophages and inducing CD8+ T cell activation in the PDAC microenvironment. Finally, the antitumor immune response derived from combination therapy is mainly dependent on CD8+ T cells, partially dependent on CD4+ T cells, and independent of natural killer cells.

CONCLUSIONS

Anti-TNFR2 and anti-PD-L1 combination therapy eradicated tumors by inhibiting their growth, relieving tumor immunosuppression, and generating robust memory recall.

Anti-Tumor Necrosis Factor Receptor 2 Antibody Combined With Anti-PD-L1 Therapy Exerts Robust Antitumor Effects in Breast Cancer

Breast cancer is a leading type of malignant tumor in women; however, the immunotherapy in breast cancer is still underappreciated. In this study, we demonstrated that tumor necrosis factor receptor 2 (TNFR2) is highly expressed in both breast tumor tissue and tumor-infiltrating immunosuppressive CD4⁺Foxp3⁺ regulatory T cells (Tregs). We found that TNFR2 antagonistic antibody reduced Foxp3 expression and the proliferation of Tregs and impaired the inhibitory effect of Tregs on CD4⁺CD25^– effector T (Teff) cells in a dose-dependent manner. The treatment of anti-TNFR2 antibody not only inhibited the proliferation of breast tumor cells in vitro but also suppressed the tumorigenesis of murine mammary carcinoma 4T1 cells in vivo. Mice recovered from tumor growth also developed 4T1-specific immunity. Furthermore, we demonstrated that anti-TNFR2 antibody in combination with anti-PD-L1 exhibited augmented antitumor effects than monotherapy. Anti-TNFR2 treatment also tended to increase the expression of proinflammatory cytokines in tumor tissues. In conclusion, our study suggests that TNFR2 antagonist could potentially offer a clinical benefit as a single agent or in combination with immune checkpoint blockade treatment for breast cancer immunotherapy.

S100A2 Is a Prognostic Biomarker Involved in Immune Infiltration and Predict Immunotherapy Response in Pancreatic Cancer

Pancreatic cancer (PC) is a highly fatal and aggressive disease with its incidence and mortality quite discouraging. It is of great significance to construct an effective prognostic signature of PC and find the novel biomarker for the optimization of the clinical decision-making. Due to the crucial role of immunity in tumor development, a prognostic model based on nine immune-related genes was constructed, which was proved to be effective in The Cancer Genome Atlas (TCGA) training set, TCGA testing set, TCGA entire set, GSE78229 set, and GSE62452 set. Furthermore, S100A2 (S100 Calcium Binding Protein A2) was identified as the gene occupying the most paramount position in risk model. Gene set enrichment analysis (GSEA), ESTIMATE and CIBERSORT algorithm revealed that S100A2 was closely associated with the immune status in PC microenvironment, mainly related to lower proportion of CD8+T cells and activated NK cells and higher proportion of M0 macrophages. Meanwhile, patients with high S100A2 expression might get more benefit from immunotherapy according to immunophenoscore algorithm. Afterwards, our independent cohort was also used to demonstrate S100A2 was an unfavorable marker of PC, as well as its remarkably positive correlation with the expression of PD-L1. In conclusion, our results demonstrate S100A2 might be responsible for the preservation of immune-suppressive status in PC microenvironment, which was identified with significant potentiality in predicting prognosis and immunotherapy response in PC patients.

Acetylation in Tumor Immune Evasion Regulation

Acetylation is considered as one of the most common types of epigenetic modifications, and aberrant histone acetylation modifications are associated with the pathological process of cancer through the regulation of oncogenes and tumor suppressors. Recent studies have shown that immune system function and tumor immunity can also be affected by acetylation modifications. A comprehensive understanding of the role of acetylation function in cancer is essential, which may help to develop new therapies to improve the prognosis of cancer patients. In this review, we mainly discussed the functions of acetylase and deacetylase in tumor, immune system and tumor immunity, and listed the information of drugs targeting these enzymes in tumor immunotherapy.