D-mannose facilitates immunotherapy and radiotherapy of triple-negative breast cancer via degradation of PD-L1

Overcoming radiation-induced PD-L1 and COX-2 upregulation by nitric oxide gas nanogenerator to sensitize radiotherapy of lung cancer

Currently, certain lung cancer patients exhibit resistance to radiotherapy due to reduced DNA damage under hypoxic conditions and the cytoprotective and immune-resistance effect caused by increased programmed death ligand-1 (PD-L1) and Cyclooxygenase 2 (COX-2) expression after radiotherapy. At present, existing nanoparticles or drugs could hardly effectively, and easily address these obstacles faced by highly effective radiotherapy simultaneously, especially the simultaneous depression of PD-L1 and COX-2. In this study, it is newly proved that some typical nitric oxide (NO) gas donors could co-inhibit PD-L1 and COX-2 expression, revealing the possible not fully proven role of NO in reversing tumor immunotherapy resistance. Then, to realize selective NO generation in tumors, a simple tumor glutathione (GSH) responsive NO gas nanogenerator named SAB-NO nanoparticles was designed and prepared, which was composed of the NO donor Isoamyl Nitrite conjugated with serum albumin (SAB). By doing this, SAB-NO nanoparticles more effectively sensitized radiotherapy through breaking the cytoprotective effects faced by radiotherapy in vitro by generating more DNA damage through reversing tumor hypoxia and impairing the DNA damage repair process through decreasing PD-L1 expression. Then, the combination therapy of SAB-NO nanoparticles and radiotherapy effectively transformed cold tumors into hot ones through avoiding some potential immune-resistance effects induced by radiotherapy treatment alone through PD-L1 and COX-2 co-inhibition. In conclusion, the combined treatment of radiotherapy and SAB-NO nanoparticles finally almost completely suppressed the growth of lung tumors, revealing the novel role of NO donors in sensitizing tumor immunotherapy by avoiding the potential cytoprotective and immune-resistance effects.

Targeting "don't eat me" signal: breast cancer immunotherapy

PURPOSE

Breast cancer ranks as the most prevalent cancer type impacting women globally, both in terms of incidence and mortality rates, making it a major health concern for females. There's an urgent requirement to delve into new cancer treatment methods to improve patient survival rates.

METHODS

Immunotherapy has gained recognition as a promising area of research in the treatment of breast cancer, with targeted immune checkpoint therapies demonstrating the potential to yield sustained clinical responses and improve overall survival rates. Presently, the predominant immune checkpoints identified on breast cancer cells include CD47, CD24, PD-L1, MHC-I, and STC-1, among others. Nevertheless, the specific roles of these various immune checkpoints in breast carcinogenesis, metastasis, and immune evasion have yet to be comprehensively elucidated. We conducted a comprehensive review of the existing literature pertaining to breast cancer and immune checkpoint inhibitors, providing a summary of findings and an outlook on future research directions.

RESULTS

This article reviews the advancements in research concerning each immune checkpoint in breast cancer and their contributions to immune evasion, while also synthesizing immunotherapy strategies informed by these mechanisms. Furthermore, it anticipates future research priorities, thereby providing a theoretical foundation to guide immunotherapy as a potential interventional approach for breast cancer treatment.

CONCLUSION

Knowledge of immune checkpoints will drive the creation of novel cancer therapies, and future breast cancer research will increasingly emphasize personalized treatments tailored to patients' specific tumor characteristics.

A DNA-Mediated Lysosomal Degradation Strategy for Targeted Degradation of PD-L1 Protein

The expression of programmed cell death ligand 1 (PD-L1) enables tumor cells to evade immune surveillance by T-cells. The level of PD-L1 on the cell surface plays a crucial role in the effectiveness of PD-L1-targeted immune checkpoint blockade therapy. Therefore, we utilized the unique trafficking capabilities of scavenger receptors (SRs) to direct PD-L1 to lysosomes for degradation. By employing click chemistry to conjugate the PD-L1 inhibitor BMS-202 with dendritic DNA scaffolds, we created a bifunctional compound, PBL1, which is capable of simultaneously targeting both SRs and PD-L1. PBL1 effectively induces PD-L1 degradation both in vitro and in vivo, significantly reducing the off-target toxicity commonly associated with traditional PD-L1 inhibitors. The efficacy and specificity of PBL1 have been validated in A549 cells and zebrafish models. The development of this SRs-mediated lysosomal degradation strategy offers a promising new approach for cancer immunotherapy, providing a safer and more targeted alternative to existing PD-L1 inhibitors.

SGlycosylation Gene Signatures as Prognostic Biomarkers in Glioblastoma

OBJECTIVE

Glioblastoma (GBM) is an aggressive brain tumor characterized by significant heterogeneity. This study investigates the role of glycosylation-related genes in GBM subtyping, prognosis, and response to therapy.

METHODS

We analyzed mRNA expression data and clinical information from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. Glycosylation-related genes were selected for differential expression analysis, sample clustering, and survival analysis. Immune cell infiltration and drug sensitivity were evaluated using CIBERSORT and oncoPredict, respectively. A prognostic model was constructed with Lasso regression.

RESULTS

GBM samples were stratified into two glycosylation-related subtypes, showing distinct survival outcomes, with higher glycosylation expression correlating with poorer prognosis. Immune microenvironment analysis revealed differences in T-cell infiltration and immune checkpoint expression between subtypes, indicating variable immunotherapy responses. The prognostic model based on glycosylation genes demonstrated significant predictive value for patient survival.

CONCLUSION

Glycosylation-related gene expression contributes to GBM heterogeneity and is a valuable biomarker for prognosis and treatment stratification. This study provides insights into personalized treatment approaches for GBM based on glycosylation-related molecular subtypes.

Curcumin exerts anti-tumor activity in colorectal cancer via gut microbiota-mediated CD8+ T Cell tumor infiltration and ferroptosis

Colorectal cancer (CRC), as a high-incidence malignancy, continues to present significant challenges in prevention, screening, and treatment. Curcumin (Cur) exhibits notable anti-inflammatory and anticancer properties. Despite its poor solubility in water and low bioavailability, high concentrations of Cur are detected in the gastrointestinal tract after oral administration, suggesting that it may directly interact with the gut microbiota and exert regulatory effects. This study aims to explore the mechanisms by which Cur improves CRC by modulating gut microbiota. Firstly, we evaluated the effect of Cur on CRC cell viability in vitro using the MTT assay, and the results showed a significant inhibitory effect on CRC cell growth. The IC50 values for Cur in CT26 and RKO cells were 23.52 μM, 16.11 μM, and 13.62 μM at 24, 48, and 72 hours, respectively, and 26.3 μM, 16.52 μM, and 14.22 μM at 24, 48, and 72 hours, respectively. Cur induced apoptosis and caused G2 phase cell cycle arrest in tumor cells. Subsequently, we established a CRC mouse model. Oral administration of Cur at 15 mg kg-1 and 30 mg kg-1 inhibited CRC progression, as evidenced by reduced tumor volume, histological analysis, immunohistochemistry, and an increased number of CD8+ T cells infiltrating the tumors. Ferroptosis in tumor cells was also observed. Cur partially restored the gut microbiota of CRC mice, altering the abundance and diversity of the gut microbiota and affecting serum metabolite distribution, with significant increases in the abundance of SCFA-producing microbes such as Lactobacillus and Kineothrix. To verify causality, we designed a fecal microbiota transplantation (FMT) experiment. Compared with CRC mice, the fecal microbiota from Cur-treated mice significantly alleviated CRC symptoms, including slowed tumor growth, enhanced CD8+ T cell tumor infiltration, and induced ferroptosis in tumor cells. Additionally, when gut microbiota was depleted with antibiotics, Cur's antitumor effects disappeared, suggesting that Cur mitigates CRC in a gut microbiota-dependent manner. These findings provide new insights into the mechanisms underlying CRC and propose novel therapeutic interventions, emphasizing the interaction between gut microbiota and immune responses within the tumor immune microenvironment (TIME).

Enhancing radiotherapy techniques for Triple-Negative breast cancer treatment

Breast cancer is the most prevalent cancer among women worldwide, with various subtypes that require distinct treatment approaches. Among these, Triple-Negative Breast Bancer (TNBC) is recognized as the most aggressive form, often associated with poor prognosis due to its lack of targeted therapeutic options. This review specifically focuses on Radiotherapy (RT) as a treatment modality for TNBC, evaluating recent advancements and ongoing challenges, particularly the issue of radioresistance. RT remains an essential part in the management of breast cancer, including TNBC. Over the years, multiple improvements have been made to enhance RT effectiveness and minimize resistance. The introduction of advanced techniques such as Stereotactic Body Radiation Therapy (SBRT) and Stereotactic Radiosurgery (SRS) has significantly improved precision and reduced toxicity. More recently, proton radiation therapy, a novel RT modality, has been introduced, offering enhanced dose distribution and reducing damage to surrounding healthy tissues. Despite these technological advancements, a subset of TNBC patients continues to exhibit resistance to RT, leading to recurrence and poor treatment outcomes. To overcome radioresistance, there is an increasing interest in combining RT with targeted therapeutic agents that sensitize cancer cells to radiation. Radiosensitizing drugs have been explored to enhance the efficacy of RT by making cancer cells more susceptible to radiation-induced damage. Potential candidates include DNA damage repair inhibitors, immune checkpoint inhibitors, and small-molecule targeted therapies that interfere with key survival pathways in TNBC cells. In conclusion, while RT remains a crucial modality for TNBC treatment, radioresistance remains a significant challenge. Future research should focus on optimizing RT techniques while integrating radiosensitizing agents to improve treatment efficacy. By combining RT with targeted drug therapy, a more effective and personalized treatment approach can be developed, ultimately improving patient outcomes and reducing recurrence rates in TNBC.

Mannose inhibits PKM2 lactylation to induce pyroptosis in bladder cancer and activate antitumor immune responses

Bladder cancer therapy remains challenging due to poor efficacy and frequent recurrence. Mannose, a naturally occurring monosaccharide, has demonstrated antitumor effects in various cancers, yet its mechanism of action in bladder cancer is unclear. This study explored the inhibitory effects of mannose on bladder cancer. We found mannose significantly inhibited the growth of bladder cancer cells, xenografts, and organoids. Mannose directly binds to PKM2, inhibiting its enzymatic activity and reducing lactate production. This reduction in lactate led to decreased PKM2 lactylation and increased acetylation, causing PKM2 to translocate to the nucleus. Nuclear PKM2 activated the NF-κB pathway, inducing NLRP1/Caspase-1/GSDMD/IL-1β-dependent pyroptosis. Additionally, mannose promoted antitumor immune responses by inducing pyroptosis and enhancing the efficacy of immune checkpoint inhibitors. These findings highlight the use of mannose as a potent antitumor agent and a promising therapeutic strategy for bladder cancer.

D-mannose suppresses the angiogenesis and progression of colorectal cancer

Angiogenesis is an important factor influencing the development of solid tumors, and vascular endothelial growth factor receptor-2 (VEGFR2) is a central regulator of angiogenesis. Antibodies and inhibitors against VEGFR2 have been widely used in various malignancies. However, the regulatory mechanism of VEGFR2 has not been fully clarified. Here, we show that D-mannose can significantly inhibit angiogenesis and tumor growth by degrading VEGFR2. Specifically, D-mannose inactivates GSK3β by promoting the phosphorylation of GSK3β at Ser9, enhances the nuclear translocation of TFE3, and promotes lysosomal biogenesis, thereby increasing the lysosome-mediated degradation of VEGFR2. Thus, D-mannose significantly inhibits the proliferation, migration, and capillary formation of human umbilical vein endothelial cells (HUVECs) in vitro. Oral administration of D-mannose dramatically inhibits angiogenesis and tumor growth in mice. Our findings reveal a previously unrecognized anti-tumor mechanism of D-mannose by destabilizing VEGFR2 and provide a new strategy for the clinical treatment of colorectal cancer (CRC).

Mannose and PMI depletion overcomes radiation resistance in HPV-negative head and neck cancer

Radiotherapy is critical component of multidisciplinary cancer care, used as a primary and adjuvant treatment for patients with head and neck squamous cell carcinoma. This study investigates how mannose, a naturally occurring monosaccharide, combined with phosphomannose isomerase (PMI) depletion, enhances the sensitivity of HPV-negative head and neck tumour models to radiation. Isogenic PMI knockout models were generated by CRISPR/Cas9 gene editing, yielding a 20-fold increase in sensitivity to mannose in vitro, and causing significant tumour growth delay in vivo. This effect is driven by metabolic reprogramming, resulting in potent glycolytic suppression coupled with consistent depletion of ATP and glycolytic intermediates in PMI-depleted models. Functionally, these changes impede DNA damage repair following radiation, resulting in a significant increase in radiation sensitivity. Mannose and PMI ablation supressed both oxygen consumption rate and extracellular acidification, pushing cells towards a state of metabolic quiescence, effects contributing to increased radiation sensitivity under both normoxic and hypoxic conditions. In 3D-tumoursphere models, metabolic suppression by mannose and PMI depletion was shown to elevate intra-tumoursphere oxygen levels, contributing to significant in vitro oxygen-mediated radiosensitisation. These findings position PMI as a promising anti-tumour target, highlighting the potential of mannose as a metabolic radiosensitiser enhancing cancer treatment efficacy.

Reprogramming of Glucose Metabolism by Nanocarriers to Improve Cancer Immunotherapy: Recent Advances and Applications

Although immunotherapy has made significant progress in cancer treatment, its limited responsiveness has greatly hindered widespread clinical application. The Warburg effect in tumor cells creates a tumor microenvironment (TME) characterized by hypoxia, low glucose levels, and high lactate levels, which severely inhibits the antitumor immune response. Consequently, targeting glucose metabolism to reprogram the TME is considered an effective strategy for reversing immunosuppression and immune evasion. Numerous studies have been conducted on enhancing cancer immunotherapy efficacy through the delivery of glucose metabolism modulators via nanocarriers. This review provides a comprehensive overview of the glucose metabolic characteristics of tumors and their impacts on the immune system, as well as nanodelivery strategies targeting glucose metabolism to enhance immunotherapy. These strategies include inhibiting key glycolytic enzymes, blocking glucose and lactate transporters, and utilizing glucose oxidase and lactate oxidase. Furthermore, this article reviews recent advancements in synergistic antitumor therapy involving glucose metabolism-targeted therapy combined with other treatments, such as chemotherapy, radiotherapy (RT), phototherapy, and immunotherapy. Finally, we discuss the limitations and future prospects of nanotechnology targeting glucose metabolism therapy, hoping to provide new directions and ideas to improve cancer immunotherapy.

Manipulating mannose metabolism as a potential anticancer strategy

Cancer cells acquire metabolic advantages over their normal counterparts regarding the use of nutrients for sustained cell proliferation and cell survival in the tumor microenvironment. Notable among the metabolic traits in cancer cells is the Warburg effect, which is a reprogrammed form of glycolysis that favors the rapid generation of ATP from glucose and the production of biological macromolecules by diverting glucose into various metabolic intermediates. Meanwhile, mannose, which is the C-2 epimer of glucose, has the ability to dampen the Warburg effect, resulting in slow-cycling cancer cells that are highly susceptible to chemotherapy. This anticancer effect of mannose appears when its catabolism is compromised in cancer cells. Moreover, de novo synthesis of mannose within cancer cells has also been identified as a potential target for enhancing chemosensitivity through targeting glycosylation pathways. The underlying mechanisms by which alterations in mannose metabolism induce cancer cell vulnerability are just beginning to emerge. This review summarizes the current state of our knowledge of mannose metabolism and provides insights into its manipulation as a potential anticancer strategy.

Mannose reduces fructose metabolism and reverses MASH in human liver slices and murine models in vivo

BACKGROUND

Fibrosis drives liver-related mortality in metabolic dysfunction-associated steatohepatitis (MASH), yet we have limited medical therapies to target MASH-fibrosis progression. Here we report that mannose, a simple sugar, attenuates MASH steatosis and fibrosis in 2 robust murine models and human liver slices.

METHODS

The well-validated fat-and-tumor MASH murine model for liver steatosis and fibrosis was employed. Mannose was supplied in the drinking water at the start ("Prevention" group) or at week 6 of the 12-week MASH regimen ("Therapy" group). The in vivo antifibrotic effects of mannose supplementation were tested in a second model of carbon tetrachloride (CCl4)-induced liver fibrosis. A quantitative and automated digital pathology approach was used to comprehensively assess steatosis and fibrosis phenotypes. Mannose was also tested in vitro in human and primary mouse hepatocytes conditioned with free fatty acids alone or with fructose, and human precision-cut liver slices from patients with end-stage MASH cirrhosis.

RESULTS

Oral mannose supplementation improved liver fibrosis in vivo in both fat-and-tumor MASH and CCl4 mouse models, as well as in human precision-cut liver slice MASH samples. Mannose also reduced liver steatosis in fat-and-tumor MASH mice, and in human and mouse hepatocytes in vitro. Ketohexokinase, the main enzyme in fructolysis, was decreased with mannose in whole mouse liver, cultured hepatocytes, and human precision-cut liver slices. Removal of fructose or overexpression of ketohexokinase each abrogated the antisteatotic effects of mannose.

CONCLUSIONS

This study identifies mannose as a novel therapeutic candidate for MASH that mitigates steatosis by dampening hepatocyte ketohexokinase expression and exerts independent antifibrotic effects in 2 mouse models and human liver tissue slices.

Metabolic Reprogramming of Anti-cancer T Cells: Targeting AMPK and PPAR to Optimize Cancer Immunotherapy

Cancer treatment era has been revolutionized by the novel therapeutic methods such as immunotherapy in recent years. Immunotherapy-based approaches are considered effective and reliable methods that has brought hope to eradicate certain cancers. Nonetheless, there are some issues, considered as critical obstacles in successful cancer immunotherapy. Such issues are attributed to the ability of the tumor cells in providing a tolerant microenvironment that impairs the immune responses, and help the cancer cells evade the immunogenic cell death. It has been suggested that the re-activation and maintenance of effector immune cells may become possible by metabolic reprogramming. Several signaling pathways have been noticed with the possibility of metabolic reprogramming of tumor-specific T cells, to overcome the metabolic restrictions in the tumor microenvironment; and among them, AMP-activated protein kinase (AMPK) and peroxisome proliferator-activated receptors (PPAR) have been investigated the most as the main energy sensors and regulators of mitochondrial biogenesis. The synergic effects of AMPK activators and/or PPAR agonists in cancer immunotherapy have been reported. In this review, we compare the roles of AMPK activators and PPAR agonists, and the efficacy of their combination in metabolic reprogramming of cytotoxic T cells in favoring cancer immunotherapy.

On-demand reprogramming of immunosuppressive microenvironment in tumor tissue via multi-regulation of carcinogenic microRNAs and RNAs dependent photothermal-immunotherapy using engineered gold nanoparticles for malignant tumor treatment

The frequent immune escape of tumor cells and fluctuating therapeutic efficiency vary with each individual are two critical issues for immunotherapy against malignant tumor. Herein, we fabricated an intelligent core-shell nanoparticle (SNAs@CCMR) to significantly inhibit the PD-1/PD-L1 mediated immune escape by on-demand regulation of various oncogenic microRNAs and perform RNAs dependent photothermal-immunotherapy to achieve precise and efficient treatment meeting the individual requirements of specific patients by in situ generation of customized tumor-associated antigens. The SNAs@CCMR consisted of antisense oligonucleotides grafted gold nanoparticles (SNAs) as core and TLR7 agonist imiquimod (R837) functionalized cancer cell membrane (CCM) as shell, in which the acid-labile Schiff base bond was used to connect the R837 and CCM. During therapy, the acid environment of tumor tissue cleaved the Schiff base to generate free R837 and SNAs@CCM. The SNAs@CCM further entered tumor cells via CCM mediated internalization, and then specifically hybridized with over-expressed miR-130a and miR-21, resulting in effective inhibition of the migration and PD-L1 expression of tumor cells to avoid their immune escape. Meanwhile, the RNAs capture also caused significant aggregation of SNAs, which immediately generated photothermal agents within tumor cells to perform highly selective photothermal therapy under NIR irradiation. These chain processes not only damaged the primary tumor, but also produced plenty of tumor-associated antigens, which matured the surrounding dendritic cells (DCs) and activated anti-tumor T cells along with the released R837, resulting in the enhanced immunotherapy with suppressive immune escape. Both in vivo and in vitro experiments demonstrated that our nanoparticles were able to inhibit primary tumor and its metastasis via multi-regulation of carcinogenic microRNAs and RNAs dependent photothermal-immune activations, which provided a promising strategy to reprogram the immunosuppressive microenvironment in tumor tissue for better malignant tumor therapy.

A PD-L1 siRNA-Loaded Boron Nanoparticle for Targeted Cancer Radiotherapy and Immunotherapy

Although the combination of radiotherapy and immunotherapy is regarded as a promising clinical treatment strategy, numerous clinical trials have failed to demonstrate synergistic effects. One of the key reasons is that conventional radiotherapies inevitably damage intratumoral effector immune cells. Boron Neutron Capture Therapy (BNCT) is a precise radiotherapy that selectively kills tumor cells while sparing adjacent normal cells, by utilizing 10B agents and neutron irradiation. Therefore, combinational BNCT-immunotherapy holds promise for achieving more effective synergistic effects. Here it develops a 10B-containing polymer that self-assembled with PD-L1 siRNA to form 10B/siPD-L1 nanoparticles for combinational BNCT-immunotherapy. Unlike antibodies, PD-L1 siRNA can inhibit intracellular PD-L1 upregulated by BNCT, activating T-cell immunity while also suppressing DNA repair. This can enhance BNCT-induced DNA damage, promoting immunogenic cell death (ICD) and further amplifying the antitumor immune effect. The results demonstrated that BNCT using 10B/siPD-L1 nanoparticles precisely killed tumor cells while sparing adjacent T cells and induced a potent antitumor immune response, inhibiting distal and metastatic tumors.

NAD+ Metabolism Reprogramming Drives SIRT1-Dependent Deacetylation Inducing PD-L1 Nuclear Localization in Cervical Cancer

Cervical cancer (CC) is a major health threat to women, with immunotherapies targeting the programmed death receptor 1/programmed death ligand 1(PD-1/PD-L1) axis showing promise but encountering resistance in a significant patient population. This resistance has driven a critical quest to uncover the underlying mechanisms. This study uncovers a novel metabolic axis involving the nicotinamide adenine dinucleotide (NAD+) salvage pathway enzyme nicotinamide phosphoribosyltransferase (NAMPT) and the deacetylase Sirtuin 1 (SIRT1), which regulates PD-L1 expression and nuclear localization in CC. This axis may be a key factor contributing to the resistance observed in immunotherapy. This study reveals that PD-L1 overexpression in cancers is regulated by both transcriptional and post-transcriptional processes. Acetyl-proteomic analysis pinpoints SIRT1 as a central regulator in the deacetylation of histone H3 at lysines 27, which may influence PD-L1 subcellular distribution. This finding reveals the epigenetic control of immune checkpoint proteins by metabolic pathways, offering a new perspective on the regulation of PD-L1. The identification of the NAMPT/SIRT1 metabolic axis as a critical factor suggests that targeting this axis may enhance therapeutic responses.

Post-translational modifications of immune checkpoints: unlocking new potentials in cancer immunotherapy

Immunotherapy targeting immune checkpoints has gained traction across various cancer types in clinical settings due to its notable advantages. Despite this, the overall response rates among patients remain modest, alongside issues of drug resistance and adverse effects. Hence, there is a pressing need to enhance immune checkpoint blockade (ICB) therapies. Post-translational modifications (PTMs) are crucial for protein functionality. Recent research emphasizes their pivotal role in immune checkpoint regulation, directly impacting the expression and function of these key proteins. This review delves into the influence of significant PTMs-ubiquitination, phosphorylation, and glycosylation-on immune checkpoint signaling. By targeting these modifications, novel immunotherapeutic strategies have emerged, paving the way for advancements in optimizing immune checkpoint blockade therapies in the future.

Targeted nanoparticle delivery system for tumor-associated macrophage reprogramming to enhance TNBC therapy

Triple-negative breast cancer (TNBC) poses as a daunting and intricate manifestation of breast cancer, highlighted by few treatment options and a poor outlook. The crucial element in fostering tumor growth and immune resistance is the polarization of tumor-associated macrophages (TAMs) into the M2 state within the tumor microenvironment (TME). To address this, we developed M2 targeting peptide-chitosan-curcumin nanoparticles (M2pep-Cs-Cur NPs), a targeted delivery system utilizing chitosan (Cs) as a carrier, curcumin (Cur) as a therapeutic agent, and targeting peptides for specificity. These NPs effectively inhibited TNBC cell proliferation (~ 70%) and invasion (~ 70%), while increasing the responsiveness of tumors to anti-PD-L1 treatment (~ 50% survival enhancement) in vitro and in vivo. Bioinformatics analysis suggested that Cur modulates TAM polarization by influencing key genes such as COX-2, offering insights into its underlying mechanisms. This study highlights the potential of M2pep-Cs-Cur NPs to reverse M2 polarization in TAMs, providing a promising targeted therapeutic strategy to overcome immunotherapy resistance and improve TNBC outcomes.

Sweet regulation - The emerging immunoregulatory roles of hexoses

BACKGROUND

It is widely acknowledged that dietary habits have profound impacts on human health and diseases. As the most important sweeteners and energy sources in human diets, hexoses take part in a broad range of physiopathological processes. In recent years, emerging evidence has uncovered the crucial roles of hexoses, such as glucose, fructose, mannose, and galactose, in controlling the differentiation or function of immune cells.

AIM OF REVIEW

Herein, we reviewed the latest research progresses in the hexose-mediated modulation of immune responses, provided in-depth analyses of the underlying mechanisms, and discussed the unresolved issues in this field.

KEY SCIENTIFIC CONCEPTS OF REVIEW

Owing to their immunoregulatory effects, hexoses affect the onset and progression of various types of immune disorders, including inflammatory diseases, autoimmune diseases, and tumor immune evasion. Thus, targeting hexose metabolism is becoming a promising strategy for reversing immune abnormalities in diseases.

Bibliometric analysis of targeted immunotherapy for osteosarcoma-current knowledge, hotspots and future perspectives

Objective

The objective of this study is to conduct a bibliometric analysis on examining the current condition, areas of interest, and rising trends of immunotherapy for osteosarcoma (ITFOS), as well as its importance in associated research domains.

Methods

An extensive collection of academic papers on the use of ITFOS was obtained from the Web of Science between January 1, 2000 and October 20, 2023. Then, using a variety of tools like HisCite, VOSviewer, CiteSpace, and the bibliometrix package, a bibliometric study was carried out. This study included the collection of information on country, institution, author, journal, and keywords.

Results

A comprehensive analysis was undertaken on a total of 616 publications obtained from 247 journals, encompassing the contributions of 3725 authors affiliated with 831 institutes spanning across 43 countries/regions. Notably, China exhibited the highest quantity of published 277 (44.99%) articles on ITFOS. The most productive institution was Zhejiang University, with 26 (4.22%) publications. The author with the highest publication output was Tsukahara, Tomohide from Japan with 15 (2.44%) publications. The article with the most citation was "DOI: 10.1200/JCO.2014.58.0225". Frontiers in Immunology demonstrated the highest level of productivity, having published a total of 31 (5.03%) articles. The most frequently used were "osteosarcoma," "immunotherapy," and "cancer,". Meanwhile, "sequencing", "prognostic signature" and "immune microenvironment" have been identified as the research frontiers for the forthcoming years.

Conclusion

This paper provides a thorough evaluation of current research trends and advancements in ITFOS. It includes relevant research findings and emphasizes collaborative efforts among authors, institutions, and countries.

Dimethyl fumarate promotes the degradation of HNF1B and suppresses the progression of clear cell renal cell carcinoma

Clear cell renal cell carcinoma (ccRCC) is the most lethal subtype of renal cancer, and its treatment options remain limited. Therefore, there is an urgent need to discover therapeutic agents for ccRCC treatment. Here, we demonstrate that dimethyl fumarate (DMF), an approved medication for multiple sclerosis [1] and psoriasis, can inhibit the proliferation of ccRCC cells. Mechanistically, hepatocyte nuclear factor 1β (HNF1B), a transcription factor highly expressed in ccRCC, is succinated by DMF at cysteine residues, leading to its proteasomal degradation. Furthermore, HNF1B interacts with and stabilizes Yes-associated protein (YAP), thus DMF-mediated HNF1B degradation decreases YAP protein level and the expression of its target genes, resulting in the suppression of ccRCC cell proliferation. Importantly, oral administration of DMF sensitizes ccRCC to sunitinib treatment and enhances its efficacy in mice. In summary, we provide evidences supporting DMF as a potential drug for clinical treatment of ccRCC by targeting HNF1B and reveal a previously unrecognized role of HNF1B in regulating YAP in ccRCC.

Lactylation: The metabolic accomplice shaping cancer's response to radiotherapy and immunotherapy

Protein lactylation, an emerging post-translational modification, is providing new insights into tumor biology and challenging our current understanding of cancer mechanisms. Our review illuminates the intricate roles of lactylation in carcinogenesis, tumor progression, and therapeutic responses, positioning it as a critical linchpin connecting metabolic reprogramming, epigenetic modulation, and treatment outcomes. We provide an in-depth analysis of lactylation's molecular mechanisms and its far-reaching impact on cell cycle regulation, immune evasion strategies, and therapeutic resistance within the complex tumor microenvironment. Notably, this review dissects the paradoxical nature of lactylation in cancer immunotherapy and radiotherapy. While heightened lactylation can foster immune suppression and radioresistance, strategically targeting lactylation cascades opens innovative avenues for amplifying the efficacy of current treatment paradigms. We critically evaluate lactylation's potential as a robust diagnostic and prognostic biomarker and explore frontier therapeutic approaches targeting lactylation. The synergistic integration of multi-omics data and artificial intelligence in lactylation research is catalyzing significant strides towards personalized cancer management. This review not only consolidates current knowledge but also charts a course for future investigations. Key research imperatives include deciphering tumor-specific lactylation signatures, optimizing synergistic strategies combining lactylation modulation with immune checkpoint inhibitors and radiotherapy, and comprehensively assessing the long-term physiological implications of lactylation intervention. As our understanding of lactylation's pivotal role in tumor biology continues to evolve, this burgeoning field promises to usher in transformative advancements in cancer diagnosis, treatment modalitie.

Glycoscience in Advancing PD-1/PD-L1-Axis-Targeted Tumor Immunotherapy

Immune checkpoint blockade therapy, represented by anti-PD-1/PD-L1 monoclonal antibodies, has significantly changed the immunotherapy landscape. However, the treatment is still limited by unsatisfactory response rates, immune-related adverse effects, and drug resistance. Current studies have established that glycosylation, a common post-translational modification, is crucial in promoting cancer progression and immune invasion. Targeting aberrant glycosylation in cancers presents precision medicine regimens for monitoring cancer progression and developing personalized medicine. Notably, the immune checkpoints PD-1 and PD-L1 are highly glycosylated, which affects PD-1/PD-L1 interaction and the binding of anti-PD-1/PD-L1 monoclonal antibodies. Recent achievements in glycoscience to enhance patient outcomes, referred to as glycotherapy, have underscored their high potency in advancing PD-1/PD-L1 blockade therapies, i.e., glycoengineered antibodies with improved binding toward PD-1/PD-L1, pharmaceutic inhibitors for core fucosylation and sialylation, and synergistic treatment with the antibody-sialidase conjugate. This review briefly introduces the PD-1/PD-L1 axis and glycosylation and highlights the fundamental and applied advances in glycoscience that improve PD-1/PD-L1 immunoblockade therapies.

Mannose Inhibits NSCLC Growth and Inflammatory Microenvironment by Regulating Gut Microbiota and Targeting OGT/hnRNP R/JUN/IL-8 Axis

Recent studies have reported direct antitumor effects of mannose, a natural six-carbon monosaccharide, in the treatment of cancer. Herein, we utilized cancer cell lines, animal models, organoids and experimental techniques such as multi-omics and cellular experiments to investigate the regulatory effects of mannose on NSCLC growth and the inflammatory microenvironment. We demonstrated that mannose can inhibit cancer cell growth, inflammatory cell infiltration and inflammatory cytokine expression in NSCLC tissue, and enhance the antitumor efficacy of immune checkpoint inhibitor both in vitro and in vivo. Orally administered mannose increased the proportion of probiotics in the gut microbiota, the abundance of anti-inflammatory and antitumor metabolites in the blood and feces of NSCLC-bearing mice. In NSCLC cells, mannose reduced JUN mRNA stability and subsequent IL-8 transcription of NSCLC cells by directly targeting OGT to suppress the O-GlcNAc glycosylation of hnRNP R, which bound and stabilized JUN mRNA in an O-GlcNAc glycosylation dependent manner. Taken together, our study demonstrated that mannose can suppress NSCLC by inhibiting tumor growth and the inflammatory microenvironment, and serve as a promising adjunct medication.

D-mannose promotes diabetic wound healing through inhibiting advanced glycation end products formation in keratinocytes

BACKGROUND

Diabetic chronic foot ulcers pose a significant therapeutic challenge around the world, resulting in adverse effects and complications in patients. D-mannose is enriched in cirtus peel and exerts beneficial effects among various diseases, especially against inflammation-related disorders.

METHODS

Here, we examined the potential effect of D-mannose during wound healing process in streptozotocin (STZ)-induced diabetes mice in vivo and by culturing keratinocytes under high glucose condition in vitro. The skin lesion healing was recorded in photos and evaluated by histochemical staining. What's more, the advanced glycation end products (AGEs) concentration in blood and mice skin was quantified. Apoptotic cells were assessed by flow cytometry and Western blotting. Inflammatory cytokines and cellular differential gene expression levels were measured by real-time PCR. The expression of the AMPK/Nrf2/HO-1 signaling-related molecules was determined by Western blotting.

RESULTS

We first found that topical supplementation of D-mannose remarkably improved skin wound healing in diabetes mice. Furthermore, both in vivo and in vitro experiments demonstrated that D-mannose reduced the AGEs generation. Mechanistically, D-mannose inhibited AGEs, then upregulated AMPK/Nrf2/HO-1 signaling in the context of high glucose to maintain keratinocyte normal functions, which positively influenced macrophage and fibroblast to accelerate diabetic wound healing. Noteworthily, these protective effects of D-mannose were abolished by the pretreatment with inhibitors of AGEs or AMPK.

CONCLUSION

As far as we know, this is the first study exploring the protective role of D-mannose on diabetic wound healing via topical supplementation. We find that D-mannose protects keratinocytes from high glucose stimulation via inhibition of AGEs formation as well as orchestrates inflammatory microenvironment in diabetic wounded skin, suggesting its supplementation as a potential therapy to promote refractory wound healing in diabetic patients.

Progress in understanding the regulatory mechanisms of immune checkpoint proteins PD-1 and PD-L1 expression

Programmed Death Protein-1 (PD-1) is a cell surface receptor that serves as a checkpoint for T cells, playing a pivotal role in regulating T-cell apoptosis. The binding of PD-1 to its ligand, Programmed Death Ligand 1 (PD-L1), inhibits anti-tumor immunity by suppressing T-cell activation signals. Indeed, the PD-1/PD-L1 pathway governs the induction and maintenance of immune tolerance within the tumor microenvironment. Consequently, the regulation of PD-1/PD-L1 immune checkpoint expression is of paramount importance. This review summarizes the mechanisms governing PD1/PD-L1 expression at various stages, including transcription, post-transcription (mRNA processing), and post-translation (protein modifications), as well as immunotherapy targeting PD1/PD-L1, aiming to further explore novel strategies for tumor immunotherapy.

Network Medicine-Based Strategy Identifies Maprotiline as a Repurposable Drug by Inhibiting PD-L1 Expression via Targeting SPOP in Cancer

Immune checkpoint inhibitors (ICIs) are drugs that inhibit immune checkpoint (ICP) molecules to restore the antitumor activity of immune cells and eliminate tumor cells. Due to the limitations and certain side effects of current ICIs, such as programmed death protein-1, programmed cell death-ligand 1, and cytotoxic T lymphocyte-associated antigen 4 (CTLA4) antibodies, there is an urgent need to find new drugs with ICP inhibitory effects. In this study, a network-based computational framework called multi-network algorithm-driven drug repositioning targeting ICP (Mnet-DRI) is developed to accurately repurpose novel ICIs from ≈3000 Food and Drug Administration-approved or investigational drugs. By applying Mnet-DRI to PD-L1, maprotiline (MAP), an antidepressant drug is repurposed, as a potential PD-L1 modifier for colorectal and lung cancers. Experimental validation revealed that MAP reduced PD-L1 expression by targeting E3 ubiquitin ligase speckle-type zinc finger structural protein (SPOP), and the combination of MAP and anti-CTLA4 in vivo significantly enhanced the antitumor effect, providing a new alternative for the clinical treatment of colorectal and lung cancer.

Sequentially Activated Smart DNA Nanospheres for Photoimmunotherapy and Immune Checkpoint Blockade

Due to the inherent immunosuppression and immune evasion of cancer cells, combining photoimmunotherapy with immune checkpoint blockade leverages phototherapy and immune enhancement, overcoming mutual limitations and demonstrating significant anticancer potential. The main challenges include nonspecific accumulation of agents, uncontrolled activation, and drug carrier safety. Smart DNA nanospheres (NS) is developed with targeted delivery and controllable release of photosensitizers and immune agents to achieve effective synergistic therapy and minimize side effects. The multifunctional NS incorporate a targeting module for programming aptamers, a response module for programming i-motif and DNA/RNA hybrid sequences, and a therapeutic module for packaging photosensitizers and PD-L1 siRNA. NS navigate to the tumor site and are sequentially activated by intracellular acid and enzymes to release photosensitizers and programmed death ligand 1 (PD-L1) small interfering RNA (siRNA)a. Besides tumor killing and immune promotion, activated NS downregulate PD-L1 expression, alleviating immune tolerance and evasion, thus enhancing the immune response. These results indicate that NS significantly enhance antitumor immune responses, synergistically improve antitumor efficacy, and reduce systemic toxicity. This study broadens the application of DNA nanomaterials in precision drug delivery and tumor therapy.

Disrupting EDEM3-induced M2-like macrophage trafficking by glucose restriction overcomes resistance to PD-1/PD-L1 blockade

BACKGROUND

Immunotherapy is beneficial for some colorectal cancer (CRC) patients, but immunosuppressive networks limit its effectiveness. Cancer-associatedfibroblasts (CAFs) are significant in immune escape and resistance toimmunotherapy, emphasizing the urgent need for new treatment strategies.

METHODS

Flow cytometric, Western blotting, proteomics analysis, analysis of public database data, genetically modified cell line models, T cell coculture, crystal violetstaining, ELISA, metabonomic and clinical tumour samples were conducted to assess the role of EDEM3 in immune escape and itsmolecular mechanisms. We evaluated theeffects of FMD plus 2-DG on antitumour immunity using multipleximmunofluorescence, flow cytometry, cytokine profiling, TUNEL assays, xenografttumours, and in vivo studies.

RESULTS

We show thatCAFs upregulate PD-L1 glycosylation and contribute to immune evasion byglycosyltransferase EDEM3. Additionally, EDEM3 plays a role in tumour immunityduring tumour progression. However, the EDEM3-mediated upregulation of PD-L1 expression underpins PD-1/PD-L1 blockade resistance in vivo. This finding contradictsthe previous trend that positive PD-L1 expression indicates a strong responseto PD-1/PD-L1 blockade. Mechanistically, high-EDEM3 expression facilitates M2-like This finding contradictsthe previous trend that positive PD-L1 expression indicates a strong responseto PD-1/PD-L1 blockade.Mechanistically, polarizationand chemotactic migration of macrophages, which are enriched in theperipheral region of tumours compared to thecore region, precluding access of CD8+ T cells to tumourfoci. Furthermore, we EDEM3 predominantly activates the recruited M2-like macrophagesvia a glucose metabolism-dependent mechanism. Manipulationof glucose utilization by a fasting-mimicking diet(FMD) plus 2-DG treatmentsynergistically with PD-1 antibody elicits potent antitumour activity byeffectively decreasing tumour glycosylated PD-L1 expression, augmenting the CD8+effector T cell infiltration and activation while concurrently reducing the infiltration.TheCAFs-EDEM3-M2-like macrophage axis plays a critical role in promotingimmunotherapy resistance. infiltration.TheCAFs-EDEM3-M2-like macrophage axis plays a critical role in promotingimmunotherapy resistance.

CONCLUSIONS

Our study suggests that blocking EDEM3-induced M2-like macro phage trafficking by FMD plus 2-DG is a promising and effective strategy to overcomeresistance to checkpoint blockade therapy offeringhope for improved treatment outcomes.

KEY POINTS

Cancer-associated fibroblasts (CAFs) can enhance PD-L1 glycosylation through the glycosyltransferase EDEM3, contributing to immune evasion during tumour progression. EDEM3 predominantly activates the recruit M2-like macrophages via a glucose metabolism-dependent mechanism. Blocking glucose utilization antagonizes recruiting and polarizing M2-like macrophages synergistically with PD-1 antibody to improve anticancer immunity.

Metabolizable alloy clusters assemble nanoinhibitor for enhanced radiotherapy of tumor by hypoxia alleviation and intracellular PD-L1 restraint

BACKGROUND

Cancer radiotherapy (RT) still has limited clinical success because of the obstacles including radioresistance of hypoxic tumors, high-dose X-ray-induced damage to adjacent healthy tissue, and DNA-damage repair by intracellular PD-L1 in tumor.

RESULTS

Therefore, to overcome these obstacles multifunctional core-shell BMS@Pt2Au4 nanoparticles (NPs) are prepared using nanoprecipitation followed by electrostatic assembly. Pt2Au4 clusters are released from BMS@Pt2Au4 NPs to alleviate tumor hypoxia by catalyzing the decomposition of endogenous H2O2 to generate O2 as well as by enhancing X-ray deposition at the tumor site, which thereby reduce the required X-ray dose. The released BMS-202 molecules simultaneously blockade PD-L1 on and in tumor cells, causing the activation of effector T cells and the inhibition of DNA-damage repair. Consequently, radiotherapy based on BMS@Pt2Au4 NPs enhance the expression of calreticulin on cancer cells, transposition of HMGB1 from the nucleus to the cytoplasm, generation of reactive oxygen species (ROS), DNA breakage and apoptosis of cancer cells in vitro. The tumor inhibition rate reached 92.5% under three cycles of 1-Gy X-ray irradiation in vivo.

CONCLUSION

In conclusion, the therapeutic outcome supports the high-efficiency of radiotherapy based on BMS@Pt2Au4 NPs in hypoxic tumors expressing PD-L1.

Adipose stem cell exosomes, stimulated by pro-inflammatory factors, enhance immune evasion in triple-negative breast cancer by modulating the HDAC6/STAT3/PD-L1 pathway through the transporter UCHL1

BACKGROUND

Triple-negative breast cancer (TNBC) is characterized by high invasiveness and metastasis potential. Ubiquitin carboxy-terminal hydrolase L1 (UCHL1) is strongly associated with breast cancer progression, although the underlying mechanisms are largely unknown.

METHODS

The gene expression profiles of TNBC samples were downloaded from the TCGA database, and ubiquitination enzymes related to immune regulation were screened. UCHL1 expression in the TNBC tissues and in adipose-derived mesenchymal stem cells (ADSCs) stimulated in vitro with pro-inflammatory cytokines were analyzed. Exosomes were isolated from these stimulated ADSCs and transfected with scrambled (si-NC) or UCHL1-specific (si-UCHL1) siRNA constructs. TNBC cells were treated with the ADSCs-derived exosomes (ADSCs-Exos) and then co-cultured with macrophages or T cells. Finally, the tumorigenic potential of the ADSCs-Exos was evaluated by injecting the exosomes into mice bearing TNBC xenografts.

RESULTS

UCHL1 was highly expressed in TNBC tissues and the stimulated ADSCs. The exosomes derived from stimulated ADSCs increased the viability and migration capacity of TNBC cells in vitro, and significantly increased Ki-67 expression through UCHL1. Furthermore, ADSCs-Exos induced M2 polarization of THP-1 monocytes by upregulating CD206 and Arg-1, and downregulating TNF-α and iNOS, and also decreased the proportion of CD3+CD8+ T cells. Mechanistically, UCHL1 regulated the STAT3 and PD-L1 signaling pathways through HDAC6. Exosomes derived from the control and cytokine-stimulated ADSCs also promoted tumor growth in vivo, and increased the expression of UCHL1, CD206, HDAC6, STAT3, and PD-L1. However, UCHL1 knockdown reversed the pro-tumorigenic effects of the ADSCs-derived exosomes in vivo and in vitro.

CONCLUSION

Pro-inflammatory factors (IFN-γ + TNF-α) stimulating ADSCs-Exos enhance immune evasion in triple-negative breast cancer by regulating the HDAC6/STAT3/PD-L1 pathway via UCHL1 transporter. Thus, UCHL1 inhibition may enhance the response of TNBC to immunotherapy.

In situ editing of tumour cell membranes induces aggregation and capture of PD-L1 membrane proteins for enhanced cancer immunotherapy

Immune checkpoint blockade (ICB) therapy has emerged as a new therapeutic paradigm for a variety of advanced cancers, but wide clinical application is hindered by low response rate. Here we use a peptide-based, biomimetic, self-assembly strategy to generate a nanoparticle, TPM1, for binding PD-L1 on tumour cell surface. Upon binding with PD-L1, TPM1 transforms into fibrillar networks in situ to facilitate the aggregation of both bound and unbound PD-L1, thereby resulting in the blockade of the PD-1/PD-L1 pathway. Characterizations of TPM1 manifest a prolonged retention in tumour ( > 7 days) and anti-cancer effects associated with reinvigorating CD8+ T cells in multiple mice tumour models. Our results thus hint TPM1 as a potential strategy for enhancing the ICB efficacy.

Photo-Thermally Controllable Tumor Metabolic Modulation to Assist T Cell Activation for Boosting Immunotherapy

Background

Glycolysis is crucial for tumor cell proliferation, supporting their energy needs and influencing the tumor microenvironment (TME). On one hand, increased lactate levels produced by glycolysis acidifies the TME, inhibiting T cell activity. On the other hand, glycolysis promotes the expression of PD-L1 through various mechanisms, facilitating immune evasion. Therefore, controlled modulation of glycolysis in tumor cells to subsequently improve the immune tumor microenvironment holds significant implications for clinical cancer treatment and immune regulation.

Methods

To reverse the immunosuppressive microenvironment caused by tumor glycolysis and reduce tumor immune escape, we developed a photo-thermal-controlled precision drug delivery platform to regulate tumor metabolism and aid in the activation of T cells, thereby enhancing immunotherapy. First, hollow mesoporous Prussian blue (HPB) was prepared, and the glycolysis inhibitor 3-bromopyruvate (3-BrPA) was encapsulated within HPB using the phase-change material 1-tetradecanol, resulting in B/T-H. This product was then modified with tumor cell membranes to obtain a photo-thermal controllable regulator (B/T-H@Membrane, B/T-HM).

Results

Due to the excellent drug loading and photo-thermal properties of HPB, upon reaching the tumor, B/T-HM can rapidly heat under 808 nm irradiation, causing the 1-tetradecanol to transition to a liquid phase and release 3-BrPA, which effectively inhibits tumor glycolysis through the HK2 pathway, thereby reducing tumor cell proliferation, decreasing lactate production, and downregulating tumor PD-L1 expression. In synergy with photo-thermal and αPD-1, this photo-thermally controllable metabolic-immune therapy effectively activates T cells to eliminate tumor.

Conclusion

In response to the changes in immune microenvironment caused by tumor metabolism, a photo-thermal precision-controlled drug delivery platform was successfully developed. This platform reshapes the tumor immunosuppressive microenvironment, providing a new approach for T cell-based tumor immunotherapy. It also opens new avenues for photo-thermal controllable metabolic-immune therapy.

Biomimetic copper-containing nanogels for imaging-guided tumor chemo-chemodynamic-immunotherapy

Developing multifunctional nanoplatforms to comprehensively modulate the tumor microenvironment and enhance diagnostic and therapeutic outcomes still remains a great challenge. Here, we report the facile construction of a multivariate nanoplatform based on cancer cell membrane (CM)-encapsulated redox-responsive poly(N-vinylcaprolactam) (PVCL) nanogels (NGs) co-loaded with Cu(II) and chemotherapeutic drug toyocamycin (Toy) for magnetic resonance (MR) imaging-guided combination tumor chemodynamic therapy/chemoimmunotherapy. We show that redox-responsive PVCL NGs formed through precipitation polymerization can be aminated, conjugated with 3,4-dihydroxyhydrocinnamic acid for Cu(II) complexation, physically loaded with Toy, and finally camouflaged with CMs. The created ADCT@CM NGs with an average size of 113.0 nm are stable under physiological conditions and can efficiently release Cu(II) and Toy under tumor microenvironment with a high level of glutathione. Meanwhile, the developed NGs are able to enhance cancer cell oxidative stress and endoplasmic reticulum stress by synergizing the effects of chemodynamic therapy mediated by Cu-based Fenton-like reaction and Toy-mediated chemotherapy, thereby triggering significant immunogenic cell death (ICD). In a melanoma mouse model, the NGs show potent immune activation effects to reinforce tumor therapeutic efficacy through ICD induction and immune modulation including high levels of immune cytokine secretion, increased tumor infiltration of CD8+ cytotoxic T cells, and reduced tumor infiltration of regulatory T cells. With the CM coating and Cu(II) loading, the developed NG platform demonstrates homologous tumor targeting and T1-weighted MR imaging, hence providing a general biomimetic NG platform for ICD-facilitated tumor theranostic nanoplatform. STATEMENT OF SIGNIFICANCE: Developing multifunctional nanoplatforms to comprehensively modulate the tumor microenvironment (TME) and enhance theranostic outcomes remains a challenge. Here, a cancer cell membrane (CM)-camouflaged nanoplatform based on aminated poly(N-vinylcaprolactam) nanogels (NGs) co-loaded with Cu(II) and toyocamycin (Toy) was prepared for magnetic resonance (MR) imaging-guided combination tumor chemodynamic therapy/chemoimmunotherapy. The tumor targeting specificity and efficient TME-triggered release of Cu(II) and Toy could enhance tumor cell oxidative stress and endoplasmic reticulum stress by synergizing the effects of chemodynamic therapy mediated by Cu-based Fenton-like reaction and Toy-mediated chemotherapy, respectively, thereby leading to significant immunogenic cell death (ICD) and immune response. With the CM coating and Cu(II) loading, the developed NG platform also demonstrates good T1-weighted tumor MR imaging performance. Hence, this study provides a general biomimetic NG platform for ICD-facilitated tumor theranostics.

D-mannose alleviates chronic periodontitis in rats by regulating the functions of neutrophils

BACKGROUND

Periodontitis is a chronic inflammatory disease characterized by the destruction of the components of the periodontium. It significantly impacts oral health and has been linked to systemic conditions like cardiovascular disease and diabetes. The critical role of neutrophils in the occurrence and development of chronic periodontitis has been paid increasing attention. The study aimed to explore the protective effects of D-mannose on chronic periodontitis and determine whether its underlying mechanisms is related to neutrophils.

METHODS

To explore the protective effects of D-mannose on chronic periodontitis, the eight-week-old Sprague Dawley rat model of lipopolysaccharide (LPS)-induced periodontitis was established, followed by D-mannose treatment by oral gavage. To evaluate the protective effects of D-mannose against periodontal bone loss, methylene blue staining, hematoxylin and eosin (H&E) staining, and micro-CT scanning were utilized. Then, immunofluorescence (IF), Western Blot, and RT-PCR were applied to assess the expression levels of pro-inflammatory cytokines (IL-1β, IL-6, and IL-17), anti-inflammatory cytokine (IL-10), tumor necrosis factor-alpha (TNF-α), granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage colony-stimulating factor (GM-CSF), ten-eleven translocation 2 (TET2), and key glycolytic enzymes (HK1, HK2, PFKFB3), and to examine D-mannose's impact on the recruitment and activation of neutrophils in the gingiva. Additionally, neutrophils isolated from the peripheral blood of healthy rats were treated with LPS and D-mannose, and changes in the expression levels of myeloperoxidase (MPO), IL-1β, IL-6, IL-17, IL-10, and TET2 were observed via IF.

RESULTS

In vivo, D-mannose inhibited LPS-induced alveolar bone resorption in rats. After D-mannose treatment, the expression levels of IL-17 (p<0.01) and TET2 (p<0.01) were suppressed by IF, and the expression levels of IL-1β (p<0.05), IL-17 (p<0.05) and TET2 (p<0.01) were downregulated by WB. The results of qPCR showed that D-mannose reduced the expression levels of IL-1β (p<0.05), IL-6 (p<0.01), IL-17 (p<0.01), TNF-α (p<0.01), G-CSF (p<0.01), GM-CSF (p<0.01), TET2 (p<0.01), HK1 (p<0.01), HK2 (p<0.01), and PFKFB3 (p<0.01). D-mannose also inhibited the recruitment and activation of neutrophils in LPS-treated rat gingival tissues. In vitro, the results of IF showed that D-mannose inhibited the activation of neutrophils stimulated by LPS, downregulated the expression of IL-1β (p < 0.05), IL-6, IL-17 (p < 0.01), and TET2 (p < 0.01), and upregulated the expression of IL-10 (p < 0.01).

CONCLUSIONS

D-mannose can alleviate chronic periodontitis in rats by regulating the functions of neutrophils, potentially associated with the expression of TET2 and glycolysis, providing new insights into the potential application of D-mannose to chronic periodontitis.

Epigenetic modification in radiotherapy and immunotherapy for cancers

Radiotherapy (RT) is one of the primary treatment modalities in managing cancer patients. Recently, combined RT and immunotherapy (IT) (i.e., radio-IT [RIT]) have been aggressively investigated in managing cancer patients. However, several issues in conducting RIT are challenging, such as incorporating advanced irradiation techniques, predictive/prognostic biomarkers, and other treatment modalities. Several clinical efforts and novel biomarkers have been introduced and developed to solve these challenges. For example, stereotactic radiosurgery/stereotactic radiotherapy, stereotactic body radiotherapy/stereotactic ablative body radiotherapy, and FLASH-RT have been applied for delivering precise irradiation to lung and liver tumors in conjunction with IT. Besides, several novel IT agents and incorporations of other therapies, such as targeted and thermal therapies, have been further investigated. The present study reviewed the emerging challenges of RIT in modern oncology. We also evaluated clinical practice, bench research, and multimodality treatments. In addition to several clinically applicable biomarkers, we emphasize the roles of advanced irradiation techniques and epigenetic modification as predictive/prognostic biomarkers and potential therapeutic targets. For example, 6(m) A-based epigenetic agents demonstrate the potential to enhance the treatment effects of RIT. However, further prospective randomized trials should be conducted to confirm their roles.

A metal-organic nanoframework for efficient colorectal cancer immunotherapy by the cGAS-STING pathway activation and immune checkpoint blockade

Immunotherapy has shown marked progress in promoting systemic anti-colorectal cancer (CRC) clinical effects. For further effectively sensitizing CRC to immunotherapy, we have engineered a pH-sensitive zeolitic imidazolate framework-8 (CS/NPs), capable of efficient cGAS-STING pathway activation and immune checkpoint blockade, by encapsulating the chemotherapeutic mitoxantrone (MTX) and immunomodulator thymus pentapeptide (TP5) and tailoring with tumor-targeting chondroitin sulfate (CS). In this nanoframework, CS endows CS/NPs with specific tumor-targeting activity and reduced systemic toxicity. Of note, the coordinated Zn2+ disrupts glycolytic processes and downregulates the expression of glucose transporter type 1 (GLUT1), thus depriving the cancer cells of their energy. Zn2+ further initiates the adenosine 5'-monophosphate activated protein kinase (AMPK) pathway, which leads to PD-L1 protein degradation and sensitizes CRC cells to immunotherapy. Moreover, the damaged double-stranded DNA during MTX treatment activates the cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) pathway, which works together with TP5 induced the proliferation and differentiation of T lymphocytes and dendritic cells to further enhance the anti-CRC immune response. Therefore, CS/NPs efficiently sensitize cells to chemotherapy and stimulate systemic antitumor immune responses both in vitro and in vivo, representing a promising strategy to increase the feasibility of CRC immunotherapy.

Cervical cancer biomarker screening based on Raman spectroscopy and multivariate statistical analysis

Cervical cancer (CC) stands as one of the most prevalent malignancies among females, and the examination of serum tumor markers(TMs) assumes paramount significance in both its diagnosis and treatment. This research delves into the potential of combining Surface-Enhanced Raman Spectroscopy (SERS) with Multivariate Statistical Analysis (MSA) to diagnose cervical cancer, coupled with the identification of prospective serum biomarkers. Serum samples were collected from 95 CC patients and 81 healthy subjects, with subsequent MSA employed to analyze the spectral data. The outcomes underscore the superior efficacy of Partial Least Squares Discriminant Analysis (PLS-DA) within the MSA framework, achieving predictive accuracy of 97.73 %, and exhibiting sensitivities and specificities of 100 % and 95.83 % respectively. Additionally, the PLS-DA model yields a Variable Importance in Projection (VIP) list, which, when coupled with the biochemical information of characteristic peaks, can be utilized for the screening of biomarkers. Here, the Random Forest (RF) model is introduced to aid in biomarker screening. The two findings demonstrate that the principal contributing features distinguishing cervical cancer Raman spectra from those of healthy individuals are located at 482, 623, 722, 956, 1093, and 1656 cm-1, primarily linked to serum components such as DNA, tyrosine, adenine, valine, D-mannose, and amide I. Predictive models are constructed for individual biomolecules, generating ROC curves. Remarkably, D-mannose of V (C-N) exhibited the highest performance, boasting an AUC value of 0.979. This suggests its potential as a serum biomarker for distinguishing cervical cancer from healthy subjects.

Radiolabelling and preclinical characterisation of [89Zr]Zr-Df-ATG-101 bispecific to PD-L1/4-1BB

PURPOSE

ATG-101, a bispecific antibody that simultaneously targets the immune checkpoint PD-L1 and the costimulatory receptor 4-1BB, activates exhausted T cells upon PD-L1 crosslinking. Previous studies demonstrated promising anti-tumour efficacy of ATG-101 in preclinical models. Here, we labelled ATG-101 with 89Zr to confirm its tumour targeting effect and tissue biodistribution in a preclinical model. We also evaluated the use of immuno-PET to study tumour uptake of ATG-101 in vivo.

METHODS

ATG-101, anti-PD-L1, and an isotype control were conjugated with p-SCN-Deferoxamine (Df). The Df-conjugated antibodies were radiolabelled with 89Zr, and their radiochemical purity, immunoreactivity, and serum stability were assessed. We conducted PET/MRI and biodistribution studies on [89Zr]Zr-Df-ATG-101 in BALB/c nude mice bearing PD-L1-expressing MDA-MB-231 breast cancer xenografts for up to 10 days after intravenous administration of [89Zr]Zr-labelled antibodies. The specificity of [89Zr]Zr-Df-ATG-101 was evaluated through a competition study with unlabelled ATG-101 and anti-PD-L1 antibodies.

RESULTS

The Df-conjugation and [89Zr]Zr -radiolabelling did not affect the target binding of ATG-101. Biodistribution and imaging studies demonstrated biological similarity of [89Zr]Zr-Df-ATG-101 and [89Zr]Zr-Df-anti-PD-L1. Tumour uptake of [89Zr]Zr-Df-ATG-101 was clearly visualised using small-animal PET imaging up to 7 days post-injection. Competition studies confirmed the specificity of PD-L1 targeting in vivo.

CONCLUSION

[89Zr]Zr-Df-ATG-101 in vivo distribution is dependent on PD-L1 expression in the MDA-MB-231 xenograft model. Immuno-PET with [89Zr]Zr-Df-ATG-101 provides real-time information about ATG-101 distribution and tumour uptake in vivo. Our data support the use of [89Zr]Zr-Df-ATG-101 to assess tumour and tissue uptake of ATG-101.

Mitochondrial metabolism blockade nanoadjuvant reversed immune-resistance microenvironment to sensitize albumin-bound paclitaxel-based chemo-immunotherapy

Currently, the efficacy of albumin-bound paclitaxel (PTX@Alb) is still limited due to the impaired PTX@Alb accumulation in tumors partly mediated by the dense collagen distribution. Meanwhile, acquired immune resistance always occurs due to the enhanced programmed cell death-ligand 1 (PD-L1) expression after PTX@Alb treatment, which then leads to immune tolerance. To fill these gaps, we newly revealed that tamoxifen (TAM), a clinically widely used adjuvant therapy for breast cancer with mitochondrial metabolism blockade capacity, could also be used as a novel effective PD-L1 and TGF-β dual-inhibitor via inducing the phosphorylation of adenosine 5'-monophosphate-activated protein kinase (AMPK) protein. Following this, to obtain a more significant effect, TPP-TAM was prepared by conjugating mitochondria-targeted triphenylphosphine (TPP) with TAM, which then further self-assembled with albumin (Alb) to form TPP-TAM@Alb nanoparticles. By doing this, TPP-TAM@Alb nanoparticles effectively decreased the expression of collagen in vitro, which then led to the enhanced accumulation of PTX@Alb in 4T1 tumors. Besides, TPP-TAM@Alb also effectively decreased the expression of PD-L1 and TGF-β in tumors to better sensitize PTX@Alb-mediated chemo-immunotherapy by enhancing T cell infiltration. All in all, we newly put forward a novel mitochondrial metabolism blockade strategy to inhibit PTX@Alb-resistant tumors, further supporting its better clinical application.

GFPT1 accelerates immune escape in breast cancer by modifying PD-L1 via O-glycosylation

BACKGROUND

Immune escape is one of the causes of poor prognosis in breast cancer (BC). Glutamine-fructose-6-phosphate transaminase 1 (GFPT1) is the first speed-limiting enzyme of the hexosamine biosynthesis pathway (HBP) and is essential for the progression of BC. Nevertheless, the mechanism of the influence of GFPT1 in BC immune escape is not clear.

METHODS

First, the level of GFPT1 in BC was analyzed by starbase, and GFPT1 expression in BC tissues was measured by qRT-PCR, western blot and IHC. Then, the O-GlcNAc levels were detected by western blot. Thereafter, Co-IP was applied to examine the relationship between GFPT1 and PD-L1. At last, a mouse model was constructed for validation in vivo.

RESULTS

Firstly, we discovered that GFPT1 was obviously strengthened in BC. Knockdown or introduction of GFPT1 correspondingly degraded and elevated O-GlcNAc levels in cells. Further researches revealed that there was a reciprocal relationship between GFPT1 and PD-L1. Mechanistically, we disclosed that GFPT1 enhanced PD-L1 protein stability through O-glycosylation. More interestingly, GFPT1 accelerated BC cell immune escape via upregulation of O-glycosylation-modified PD-L1. In vivo, silencing of GFPT1 attenuated immune escape of BC cells by reducing PD-L1 levels.

CONCLUSION

GFPT1 promoted BC progression and immune escape via O-glycosylation-modified PD-L1. GFPT1 may be a potential target for BC therapy.

PD-L1 deglycosylation promotes its nuclear translocation and accelerates DNA double-strand-break repair in cancer

Resistance to radiotherapy is a major barrier during cancer treatment. Here using genome-scale CRISPR/Cas9 screening, we identify CD274 gene, which encodes PD-L1, to confer lung cancer cell resistance to ionizing radiation (IR). Depletion of endogenous PD-L1 delays the repair of IR-induced DNA double-strand breaks (DSBs) and PD-L1 loss downregulates non-homologous end joining (NHEJ) while overexpression of PD-L1 upregulates NHEJ. IR induces translocation of PD-L1 from the membrane into nucleus dependent on deglycosylation of PD-L1 at N219 and CMTM6 and leads to PD-L1 recruitment to DSBs foci. PD-L1 interacts with Ku in the nucleus and enhances Ku binding to DSB DNA. The interaction between the IgC domain of PD-L1 and the core domain of Ku is required for PD-L1 to accelerate NHEJ-mediated DSB repair and produce radioresistance. Thus, PD-L1, in addition to its immune inhibitory activity, acts as mechanistic driver for NHEJ-mediated DSB repair in cancer.

Regulation of post-translational modification of PD-L1 and associated opportunities for novel small-molecule therapeutics

PD-L1 is overexpressed on the surface of tumor cells and binds to PD-1, resulting in tumor immune escape. Therapeutic strategies to target the PD-1/PD-L1 pathway involve blocking the binding. Immune checkpoint inhibitors have limited efficacy against tumors because PD-L1 is also present in the cytoplasm. PD-L1 of post-translational modifications (PTMs) have uncovered numerous mechanisms contributing to carcinogenesis and have identified potential therapeutic targets. Therefore, small molecule inhibitors can block crucial carcinogenic signaling pathways, making them a potential therapeutic option. To better develop small molecule inhibitors, we have summarized the PTMs of PD-L1. This review discusses the regulatory mechanisms of small molecule inhibitors in carcinogenesis and explore their potential applications, proposing a novel approach for tumor immunotherapy based on PD-L1 PTM.

N-linked glycosylation of PD-L1/PD-1: an emerging target for cancer diagnosis and treatment

During tumorigenesis and progression, the immune checkpoint programmed death-1 (PD-1) and its ligand programmed death ligand-1 (PD-L1) play critical roles in suppressing T cell-mediated anticancer immune responses, leading to T-cell exhaustion and subsequent tumor evasion. Therefore, anti-PD-L1/PD-1 therapy has been an attractive strategy for treating cancer over the past decade. However, the overall efficacy of this approach remains suboptimal, revealing an urgent need for novel insights. Interestingly, increasing evidence indicates that both PD-L1 on tumor cells and PD-1 on tumor-specific T cells undergo extensive N-linked glycosylation, which is essential for the stability and interaction of these proteins, and this modification promotes tumor evasion. In various preclinical models, targeting the N-linked glycosylation of PD-L1/PD-1 was shown to significantly increase the efficacy of PD-L1/PD-1 blockade therapy. Furthermore, deglycosylation of PD-L1 strengthens the signal intensity in PD-L1 immunohistochemistry (IHC) assays, improving the diagnostic and therapeutic relevance of this protein. In this review, we provide an overview of the regulatory mechanisms underlying the N-linked glycosylation of PD-L1/PD-1 as well as the crucial role of N-linked glycosylation in PD-L1/PD-1-mediated immune evasion. In addition, we highlight the promising implications of targeting the N-linked glycosylation of PD-L1/PD-1 in the clinical diagnosis and treatment of cancer. Our review identifies knowledge gaps and sheds new light on the cancer research field.

Causality of metabolites and metabolic pathways on cholestatic liver diseases: a Mendelian randomization study

Background and Aims

Blood metabolite abnormalities have revealed an association with cholestatic liver diseases (CLDs), while the underlying metabolic mechanisms have remained sluggish yet. Accordingly, the present evaluation aims to investigate the causal relationship between blood metabolites and the risk of two major CLDs, including primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC).

Methods

Univariable and multivariable Mendelian randomization (MR) approaches were employed to uncover potential causal associations between blood metabolites and 2 CLDs, including PBS and PSC, through extracting instrumental variables (IVs) for metabolites from genome-wide association studies (GWAS) conducted on European individuals. The GWAS summary data of PBC or PSC were sourced from two distinct datasets. The initial analysis employed inverse variance weighted (IVW) and an array of sensitivity analyses, followed by replication and meta-analysis utilizing FinnGen consortium data. Finally, a multivariable MR analysis was carried out to ascertain the independent effects of each metabolite. Furthermore, the web-based tool MetaboAnalyst 5.0 was used to perform metabolic pathway examination.

Results

A genetic causality between 15 metabolites and CLDs was recognized after preliminary analysis and false discovery rate (FDR) correction. Subsequently, 9 metabolites consistently represented an association through replication and meta-analysis. Additionally, the independent causal effects of 7 metabolites were corroborated by multivariable MR analysis. Specifically, the metabolites isovalerylcarnitine (odds ratio [OR] = 3.146, 95% confidence intervals [CI]: 1.471-6.726, p = 0.003), valine (OR = 192.44, 95%CI: 4.949-7483.27, p = 0.005), and mannose (OR = 0.184, 95%CI: 0.068-0.499, p < 0.001) were found to have a causal relationship with the occurrence of PBC. Furthermore, erythrose (OR = 5.504, 95%CI: 1.801-16.821, p = 0.003), 1-stearoylglycerophosphocholine (OR = 6.753, 95%CI: 2.621-17.399, p = 7.64 × 10-5), X-11847 (OR = 0.478, 95%CI: 0.352-0.650, p = 2.28 × 10-6), and X-12405 (OR = 3.765, 95%CI: 1.771-8.005, p = 5.71 × 10-4) were independently associated with the occurrence of PSC. Furthermore, the analysis of metabolic pathways identified seven significant pathways in two CLDs.

Conclusion

The findings of the present study have unveiled robust causal relationships between 7 metabolites and 2 CLDs, thereby providing novel insights into the metabolic mechanisms and therapeutic strategies for these disorders.

Mitochondria-Targeted Nanoadjuvants Induced Multi-Functional Immune-Microenvironment Remodeling to Sensitize Tumor Radio-Immunotherapy

It is newly revealed that collagen works as a physical barrier to tumor immune infiltration, oxygen perfusion, and immune depressor in solid tumors. Meanwhile, after radiotherapy (RT), the programmed death ligand-1 (PD-L1) overexpression and transforming growth factor-β (TGF-β) excessive secretion would accelerate DNA damage repair and trigger T cell exclusion to limit RT efficacy. However, existing drugs or nanoparticles can hardly address these obstacles of highly effective RT simultaneously, effectively, and easily. In this study, it is revealed that inducing mitochondria dysfunction by using oxidative phosphorylation inhibitors like Lonidamine (LND) can serve as a highly effective multi-immune pathway regulation strategy through PD-L1, collagen, and TGF-β co-depression. Then, IR-LND is prepared by combining the mitochondria-targeted molecule IR-68 with LND, which then is loaded with liposomes (Lip) to create IR-LND@Lip nanoadjuvants. By doing this, IR-LND@Lip more effectively sensitizes RT by generating more DNA damage and transforming cold tumors into hot ones through immune activation by PD-L1, collagen, and TGF-β co-inhibition. In conclusion, the combined treatment of RT and IR-LND@Lip ultimately almost completely suppressed the growth of bladder tumors and breast tumors.

Mitochondria Energy Metabolism Depression as Novel Adjuvant to Sensitize Radiotherapy and Inhibit Radiation Induced-Pulmonary Fibrosis

Currently, the typical combination therapy of programmed death ligand-1 (PD-L1) antibodies with radiotherapy (RT) still exhibits impaired immunogenic antitumor response in clinical due to lessened DNA damage and acquired immune tolerance via the upregulation of some other immune checkpoint inhibitors. Apart from this, such combination therapy may raise the occurrence rate of radiation-induced lung fibrosis (RIPF) due to enhanced systemic inflammation, leading to the ultimate death of cancer patients (average survival time of about 3 years). Therefore, it is newly revealed that mitochondria energy metabolism regulation can be used as a novel effective PD-L1 and transforming growth factor-β (TGF-β) dual-downregulation method. Following this, IR-TAM is prepared by conjugating mitochondria-targeted heptamethine cyanine dye IR-68 with oxidative phosphorylation (OXPHOS) inhibitor Tamoxifen (TAM), which then self-assembled with albumin (Alb) to form IR-TAM@Alb nanoparticles. By doing this, tumor-targeting IR-TAM@Alb nanoparticle effectively reversed tumor hypoxia and depressed PD-L1 and TGF-β expression to sensitize RT. Meanwhile, due to the capacity of heptamethine cyanine dye in targeting RIPF and the function of TAM in depressing TGF-β, IR-TAM@Alb also ameliorated fibrosis development induced by RT.

Serum sickness-like reaction to D-supplement: a case report

BACKGROUND

Serum Sickness-Like Reaction (SSLR) is an immune response characterized by rash, polyarthralgias, inflammation, and fever. Serum sickness-like reaction is commonly attributed to antibiotics, anticonvulsants, and anti-inflammatory agents.

CASE PRESENTATION

A 16-year-old female with a history of overactive bladder and anemia presented with a diffuse urticarial rash, headaches, joint pain, and swelling for three days. Her medications included oral contraceptive pills, iron, mirabegron, UQora, and a probiotic. Physical examination revealed a diffuse urticarial rash, and her musculoskeletal exam revealed swelling and tenderness in her wrists. She was evaluated by her pediatrician and started on a 7-day course of prednisone, as well as antihistamines. Her CBC, basic metabolic panel, liver function panel, Lyme titers, and urinalysis were all within normal limits. With concern for hypersensitivity reaction to medication, all medications were discontinued. Nine days after symptom onset, the patient was evaluated by an allergist, who confirmed her presentation was consistent with serum sickness-like reaction. Her symptoms resolved, and her medications were re-introduced sequentially over several months. Restarting UQora, however, triggered a recurrence of her symptoms, and it was identified as the culprit medication. Consequently, UQora was permanently discontinued, and the patient has remained symptom-free.

CONCLUSIONS

This case report describes the first documented case of serum sickness-like reaction caused by UQora (active ingredient D-mannose). D-mannose is a monosaccharide, and it is frequently promoted to prevent urinary tract infections. While the clinical features and timeline in this case were typical of serum sickness-like reaction, UQora as the trigger was highly unusual. Clinicians should be aware of the diverse triggers of serum sickness-like reaction and the importance of prompt identification and management to enhance patient safety. Further research is necessary to better understand the potential therapeutic applications of D-mannose, as well as the potential risks and interactions.

Protein O-fucosyltransferase 1 promotes PD-L1 stability to drive immune evasion and directs liver cancer to immunotherapy

BACKGROUND AND AIMS

The immunosuppressive tumor microenvironment (TME) plays an essential role in cancer progression and immunotherapy response. Despite the considerable advancements in cancer immunotherapy, the limited response to immune checkpoint blockade (ICB) therapies in patients with hepatocellular carcinoma (HCC) remains a major challenge for its clinical implications. Here, we investigated the molecular basis of the protein O-fucosyltransferase 1 (POFUT1) that drives HCC immune evasion and explored a potential therapeutic strategy for enhancing ICB efficacy.

METHODS

De novo MYC/Trp53-/- liver tumor and the xenograft tumor models were used to evaluate the function of POFUT1 in immune evasion. Biochemical assays were performed to elucidate the underlying mechanism of POFUT1-mediated immune evasion.

RESULTS

We identified POFUT1 as a crucial promoter of immune evasion in liver cancer. Notably, POFUT1 promoted HCC progression and inhibited T-cell infiltration in the xenograft tumor and de novo MYC/Trp53-/- mouse liver tumor models. Mechanistically, we demonstrated that POFUT1 stabilized programmed death ligand 1 (PD-L1) protein by preventing tripartite motif containing 21-mediated PD-L1 ubiquitination and degradation independently of its protein-O-fucosyltransferase activity. In addition, we further demonstrated that PD-L1 was required for the tumor-promoting and immune evasion effects of POFUT1 in HCC. Importantly, inhibition of POFUT1 could synergize with anti-programmed death receptor 1 therapy by remodeling TME in the xenograft tumor mouse model. Clinically, POFUT1 high expression displayed a lower response rate and worse clinical outcome to ICB therapies.

CONCLUSIONS

Our findings demonstrate that POFUT1 functions as a novel regulator of tumor immune evasion and inhibition of POFUT1 may be a potential therapeutic strategy to enhance the efficacy of immune therapy in HCC.

Palm Kernel Cake Extracts Obtained from the Combination of Bacterial Fermentation and Enzymic Hydrolysis Promote Swine Small Intestine IPEC-J2 Cell Proliferation and Alleviate LPS-Induced Inflammation In Vitro

Co-fermentation with bacteria and enzymes can reduce sugar content in palm kernel cake (PKC); however, the chemical changes and their effects on cell functionality are unclear. This study investigated the active components in pre-treated PKC extracts and their effects on pig small intestine IPEC-J2 cell proliferation and LPS-induced inflammation. The extracts contained 60.75% sugar, 36.80% mannose, 1.75% polyphenols and 0.59% flavone, as determined by chemical analyses, suggesting that the extracts were palm kernel cake oligosaccharides (PKCOS). Then, we found that 1000 µg/mL PKCOS counteracted the decrease in cell viability (CCK8 kit) caused by LPS induction by 5 µg/mL LPS (p < 0.05). Mechanistic studies conducted by RNA-seq and qPCR analyses suggested PKCOS promoted cell proliferation through the upregulation of TNF-α, PI3KAP1, MAP3K5 and Fos in the PI3K/MAPK signalling pathway; alleviated inflammation caused by LPS via the downregulation of the target genes Casp3 and TNF-α in association with apoptosis; and regulated the expression of the antioxidant genes SOD1, SOD2 and GPX4 to exert positive antioxidant effects (p < 0.05). Furthermore, PKCOS upregulated SLC5A1 (encoding SLGT1), HK and MPI in the glycolytic pathway (p < 0.05), suggesting cell survival. In summary, PKCOS has positive effects on promoting swine intestine cell proliferation against inflammation.