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Immune cell therapy based on chimeric antigen receptor (CAR) technology platform has been greatly developed. The types of CAR immune cell therapy have expanded from T cells to innate immune cells such as NK cells and macrophages, and the diseases treated have expanded from hematological malignancies to non-tumor fields such as infectious diseases and autoimmune diseases. Among them, CAR-T and CAR-NK therapy have observed examples of rapid remission in approved clinical trials, but the efficacy is unstable and plagued by tumor resistance. Trogocytosis is a special phenomenon of intercellular molecular transfer that is common in the immune system and is achieved by recipient cells through acquisition and internalization of donor cell-derived molecules and mediates immune effects. Recently, a novel short-term drug resistance mechanism based on trogocytosis has been proposed, and the bidirectional molecular exchange between CAR immune cells and tumor cells triggered by trogocytosis partially explains the long-term relapse phenomenon after treatment with CAR immune cells. In this review, we summarize the research progress of trogocytosis in CAR immunotherapy, discuss the influencing factors of trogocytosis and its direct and indirect interference with CAR immune cells and emphasize that the interference of trogocytosis can further release the potential of CAR immune cell therapy. [ABSTRACT FROM AUTHOR]

Adaptive anti-tumor immunity is currently dependent on the natural immune system of the body. The emergence of tumor immunotherapy has improved prognosis and prolonged the survival cycle of patients. Current mainstream immunotherapies, including immune checkpoint blockade, chimeric antigen receptor T-cell immunotherapy, and monoclonal antibody therapy, are linked to natural immunity. The cGAS-STING pathway is an important natural immunity signaling pathway that plays an important role in fighting against the invasion of foreign pathogens and maintaining the homeostasis of the organism. Increasing evidence suggests that the cGAS-STING pathway plays a key role in tumor immunity, and the combination of STING-related agonists can significantly enhance the efficacy of immunotherapy and reduce the emergence of immunotherapeutic resistance. However, the cGAS-STING pathway is a doubleedged sword, and its activation can enhance anti-tumor immunity and immunosuppression. Immunosuppressive cells, including M2 macrophages, MDSC, and regulatory T cells, in the tumor microenvironment play a crucial role in tumor escape, thereby affecting the immunotherapy effect. The cGAS-STING signaling pathway can bi-directionally regulate this group of immunosuppressive cells, and targeting this pathway can affect the function of immunosuppressive cells, providing new ideas for immunotherapy. In this study, we summarize the activation pathway of the cGAS-STING pathway and its immunological function and elaborate on the key role of this pathway in immune escape mediated by the tumor immunosuppressive microenvironment. Finally, we summarize the mainstream immunotherapeutic approaches related to this pathway and explore ways to improve them, thereby providing guidelines for further clinical services. [ABSTRACT FROM AUTHOR]

Gallbladder cancer (GBC) is the most common malignant tumor of the biliary system, with poor response to current treatments. Abnormal alternative splicing has been associated with the development of a variety of tumors. Combining the GEO database and GBC mRNA‐seq analysis, it is found high expression of the splicing factor polypyrimidine region‐ binding protein 3 (PTBP3) in GBC. Multi‐omics analysis revealed that PTBP3 promoted exon skipping of interleukin‐18 (IL‐18), resulting in the expression of ΔIL‐18, an isoform specifically expressed in tumors. That ΔIL‐18 promotes GBC immune escape by down‐regulating FBXO38 transcription levels in CD8+T cells to reduce PD‐1 ubiquitin‐mediated degradation is revealed. Using a HuPBMC mouse model, the role of PTBP3 and ΔIL‐18 in promoting GBC growth is confirmed, and showed that an antisense oligonucleotide that blocked ΔIL‐18 production displayed anti‐tumor activity. Furthermore, that the H3K36me3 promotes exon skipping of IL‐18 by recruiting PTBP3 via MRG15 is demonstrated, thereby coupling the processes of IL‐18 transcription and alternative splicing. Interestingly, it is also found that the H3K36 methyltransferase SETD2 binds to hnRNPL, thereby interfering with PTBP3 binding to IL‐18 pre‐mRNA. Overall, this study provides new insights into how aberrant alternative splicing mechanisms affect immune escape, and provides potential new perspectives for improving GBC immunotherapy. [ABSTRACT FROM AUTHOR]

Pseudorabies virus (PRV) can establish lifelong latent infection in peripheral nervous ganglion, and persistent infections in peripheral blood lymphocytes. Establishing an infection in the lymphocytes does not only enable the PRV to escape host immune surveillance but pass through the placental barrier, leading to fetal death and abortion. Due to the pathogenicity of the PRV, it poses a huge challenge in its prevention and control. The PRV escapes host immunity through downregulation of swine leukocyte antigen class I (SLA I) molecules on infected cells. However, data on the molecular mechanisms of the SLA I suppression remains scant. Here, in order to verify the effect of candidate proteins PRV pUL44 and pUS6 on PRV immune escape related molecules SLA I and peptide loading complex (PLC), we detected the expression of SLA I and PLC components after expressing PRV pUL44 and pUS6. The effects of pUS6 and pUL44 on SLA I and PLC were analyzed by qRT-PCR and Western blot at mRNA and protein level, respectively. Cells expressing pUS6 or pUL44 genes showed a significantly suppressed expression of surface and total SLA I molecules. In addition, unlike UL44, the US6 gene was shown to downregulate the transporter associated with antigen processing 1 (TAP1), TAP2 and Tapasin molecules. The results show that PRV pUS6 may participate in virus immune escape by directly regulating the SLA I, TAP dimer and Tapasin molecules, thus blocking the transportation of TAP-bound peptides to the ER to bind SLA I molecules. We provide a theoretical basis on the mechanism of TAP mediated immune escape by the PRV. [ABSTRACT FROM AUTHOR]

Recent studies have identified that metabolic reprogramming in lung adenocarcinoma cells, particularly lactate metabolism disorders, plays a crucial role in tumor development and immune therapy response. The accumulation of lactic acid not only provides energy support for the proliferation of tumor cells but also affects the function of immune cells by changing the tumor microenvironment, thereby promoting immune escape. Immunotherapy, especially the application of immune checkpoint inhibitors, has become an important strategy for treating lung adenocarcinoma. However, lactate metabolism disorders might affect the efficacy of immunotherapy, leading to resistance in some patients. Therefore, a thorough understanding of the mechanisms of lactic acid metabolism in lung adenocarcinoma and its impact on the response to immunotherapy is essential for developing new therapeutic strategies and improving the efficacy of immunotherapy. This review summarizes the role of lactate metabolism disorders in the development and immunotherapy of lung adenocarcinoma, discusses the potential role of lactic acid metabolism-related genes and pathways in lung adenocarcinoma, and explores the progress in therapeutic strategies targeting lactic acid metabolism regulation. This work aims to provide new insights for the treatment of lung adenocarcinoma. [ABSTRACT FROM AUTHOR]

Immune escape and metabolic reprogramming are two essential hallmarks of cancer. Mucin-16 (MUC16) has been linked to glycolysis and immune response in different cancers. However, its involvement in nasopharyngeal carcinoma (NPC) has not been well described. We seek to dissect the functions and detailed mechanisms of MUC16 in NPC. Bioinformatics prediction was performed to identify NPC-related molecules. MUC16 was significantly enhanced in NPC tissues, which was correlated with the advanced tumor stage of patients. Lentiviral plasmids-mediated MUC16 deletion inhibited the malignant behavior of NPC cells, and glycolysis inhibition by MUC16 deletion blocked immune escape in NPC cells. E74-like factor 3 (ELF3) bound to the MUC16 promoter promotes the transcription of MUC16. MUC16 overexpression reversed the repressive effect of ELF3 silencing on glycolysis and immune escape in NPC and accelerated tumor growth in vivo. Overexpression of ELF3 in NPC was associated with reduced DNA methylation in its promoter. Our findings revealed the role of the ELF3/MUC16 axis in the immune escape and metabolic reprogramming of NPC, providing potential therapeutic targets for NPC. [ABSTRACT FROM AUTHOR]

Background: Epstein–Barr virus (EBV) is a double‐stranded DNA herpesvirus and establishes life‐long infection in 95% of the world's populations. Main body: EBV is critically involved in multiple diseases. Aberrant signaling pathways, immune escape, and metabolic reprogramming play essential roles in EBV‐mediated pathogenesis. However, the underlying mechanisms have not yet been fully elucidated. Here we reviewed recent advances on the epigenetic regulation of EBV pathogenesis, which may translate to potential therapeutic strategies in EBV‐associated diseases. Conclusion: Growing evidence has suggested that viral infections reconstruct epigenome to modulate gene expression both in the host and the virus levels. [ABSTRACT FROM AUTHOR]

Significance: Preclinical and clinical research in the past two decades has redefined the mechanism of action of some chemotherapeutics that are able to activate the immune system against cancer when cell death is perceived by the immune cells. This immunogenic cell death (ICD) activates antigen-presenting cells (APCs) and T cells to induce immune-mediated tumor clearance. One of the key requirements to achieve this effect is the externalization of the damage-associated molecular patterns (DAMPs), molecules released or exposed by cancer cells during ICD that increase the visibility of the cancer cells by the immune system. Recent Advances: In this review, we focus on the role of calreticulin (CRT) and other endoplasmic reticulum (ER) chaperones, such as the heat-shock proteins (HSPs) and the protein disulfide isomerases (PDIs), as surface-exposed DAMPs. Once exposed on the cell membrane, these proteins shift their role from that of ER chaperone and regulator of Ca2+ and protein homeostasis to act as an immunogenic signal for APCs, driving dendritic cell (DC)-mediated phagocytosis and T-mediated antitumor response. Critical Issues: However, cancer cells exploit several mechanisms of resistance to immune attack, including subverting the exposure of ER chaperones on their surface to avoid immune recognition. Future Directions: Overcoming these mechanisms of resistance represents a potential therapeutic opportunity to improve cancer treatment effectiveness and patient outcomes. [ABSTRACT FROM AUTHOR]

Summary: Recently, an antibody which inhibits the glycoprotein A repetitions predominant (GARP)‐mediated release of active transforming growth factor beta (TGFβ) from the TGFβ propeptide latency‐associated peptide (LAP) showed preclinical activity in a murine model of the chronic myeloproliferative neoplasms (MPN). Consequently, we investigated the expression of the immunosuppressive molecules LAP and GARP on peripheral blood lymphocytes from 56 MPN patients and 11 healthy donors (HD). We found that lymphocytes from patients with MPN express higher levels of LAP and GARP with no strong differences found between the different MPN diagnoses. The impact of clinical parameters on the expression of LAP and GARP by lymphocytes showed that patients with calreticulin (CALR)mut MPN have increased expression compared with HD and patients with the Januskinase2 (JAK2) mutation. The fraction of lymphocytes bound to activated platelets (aPLT) strongly correlate to LAP and GARP expression suggesting that it is not the lymphocytes themselves but aPLT, which confer the increased expression of GARP and LAP on MPN patient lymphocytes. Notably, no differences in neither platelet counts nor anti‐thrombotic therapy was identified between patients with JAK2‐ and CALRmut patients. Analysis of platelet gene expression failed to identify differences in expression of relevant genes between JAK2‐ and CALRmut patients. [ABSTRACT FROM AUTHOR]

Purpose: Increased expression of leukocyte immunoglobulin-like receptor subfamily B member 2 (LILRB2) is associated with immune evasion in breast cancer (BC). The aim of this study to elucidate the role of LILRB2 in BC progression. Methods: LILRB2 expression in tumor tissues was detected by immunohistochemical staining. Human leukocyte antigen A (HLA-A) expression in BC cells was detected by Western blotting, and HLA-A ubiquitination was detected by immunoprecipitation and histidine pulldown assay. An in-situ tumor model was established in nude BALB/c mice to verify the role of LILRB2 in immune escape. Finally, the functions and potential mechanisms of LILRB2 in BC progression were explored using in silico data. Results: LILRB2 was upregulated in BC tissues and cells, and correlated positively with poor prognosis. LILRB2 promoted BC progression by downregulating HLA-A expression. Mechanistically, LILRB2 facilitates the ubiquitination and subsequent degradation of HLA-A by promoting the interaction between the ubiquitin ligase membrane-associated ring finger protein 9 (MARCH9) and HLA-A. In syngeneic graft mouse models, LILRB2-expressing BC cells evaded CD8 + T cells and inhibited the secretion of cytokines by the cytotoxic CD8 + T cells. Conclusion: LILRB2 downregulates HLA-A to promote immune evasion in BC cells and is a promising new target for BC treatment. [ABSTRACT FROM AUTHOR]

N6-methyladenosine (m6A) functions as an important regulator in various human cancers, including gastric cancer. The immunotherapy targeting PD-1/PD-L1 has brought hope for advanced gastric cancer therapeutic. Here, present research aims to investigate the roles of m6A reader IGF2BP1 on gastric cancer tumor development and immune escape. Results indicated that IGF2BP1 up-regulated in the gastric cancer tissue and correlated with poor prognosis of gastric cancer patients. IGF2BP1 overexpression augmented the proliferation of co-cultured gastric cancer cells, and mitigated the CD8+ T cells mediated anti-tumor response, including IFN-γ secretion, surface PD-L1 level, and cytotoxicity of CD8+ T cells. Meanwhile, IGF2BP1 silencing exerted the opposite effects. In silico analysis revealed that there was a remarkable m6A modified site on PD-L1 mRNA. Moreover, the IGF2BP1 overexpression enhanced the stability of PD-L1 mRNA, thereby deteriorating the immune escape of gastric cancer cells. Collectively, these results describe a novel regulatory mechanism of IGF2BP1 by regulating PD-L1 through m6A epigenetic modification, which might provide insights for gastric cancer immunotherapies. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC) is the primary malignancy of hepatocytes and the second most common cause of cancer-related mortality across the globe. Despite significant advancements in screening, diagnosis, and treatment modalities for HCC, the mortality-to-incidence ratio remain unacceptably high. A recent study indicates that a minor population of HCCs are AFP negative or express the normal range of AFP levels. Although it is a gold standard and a more reliable biomarker in the advanced stage of HCC and poorly differentiated tumors, it does not serve as a suitable means for screening HCC. AFP plays a significant role in the development and progression of HCC and understanding its role is crucial. By examining the molecular mechanisms involved in AFP-mediated tumorigenesis, we can better understand HCC pathogenesis and identify potential therapeutic targets. This article details the role of alpha-fetoprotein (AFP) in the carcinogenic transformation of hepatocytes. The article also focuses on information about the structure, biosynthesis, and regulation of AFP at the gene level. Additionally, it discusses the immune evasion, metastasis, and control of gene expression that AFP mediates during HCC. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC) is a common and lethal tumor worldwide. Atractylenolide II (AT-II) is a natural sesquiterpenoid monomer, with anti-tumor effect. To address the effect and mechanisms of AT-II on HCC. The role and mechanisms of AT-II were assessed through cell counting kit-8, flow cytometry, enzyme-linked immunosorbent assay, immunofluorescence, and western blot experiments in Hep3B and Huh7 cells. In vivo experiments were conducted in BALB/c nude mice using immunohistochemistry and western blot assays. AT-II decreased the cell viability of Hep3B and Huh7 cells with a IC50 of 96.43 µM and 118.38 µM, respectively. AT-II increased relative Fe2+ level, which was further promoted with the incubation of erastin and declined with the ferrostatin-1 in Hep3B and Huh7 cells. AT-II enhanced the level of ROS and MDA, but reduced the GSH level, and the expression of xCT and GPX4. AT-II elevated the percent of CD8+ T cells and the IFN-γ contents, and declined the IL-10 concentrations and the expression of PD-L1 in Hep3B and Huh7 cells. AT-II downregulated the relative protein level of TRAF6, p-p65/p-65, and p-IkBα/IkBα, which was rescued with overexpression of TRAF6. Upregulation of TRAF6 also reversed the effect of AT-II on proliferation, ferroptosis, and immune escape in Hep3B cells. In vivo, AT-II reduced tumor volume and weight, the level of GPX4, xCT, and PD-L1, and the expression of TRAF6, p-p65/p-65, and p-IkBα/IkBα, with the increased expression of CD8. AT-II modulated the proliferation, ferroptosis, and immune escape of HCC cells by downregulating the TRAF6/NF-κB pathway. [ABSTRACT FROM AUTHOR]

Ferroptosis is a newly identified form of programmed cell death that is connected to iron-dependent lipid peroxidization. It involves a variety of physiological processes involving iron metabolism, lipid metabolism, oxidative stress, and biosynthesis of nicotinamide adenine dinucleotide phosphate, glutathione, and coenzyme Q10. So far, it has been discovered to contribute to the pathological process of many diseases, such as myocardial infarction, acute kidney injury, atherosclerosis, and so on. Macrophages are innate immune system cells that regulate metabolism, phagocytize pathogens and dead cells, mediate inflammatory reactions, promote tissue repair, etc. Emerging evidence shows strong associations between macrophages and ferroptosis, which can provide us with a deeper comprehension of the pathological process of diseases and new targets for the treatments. In this review, we summarized the crosstalk between macrophages and ferroptosis and anatomized the application of this association in disease treatments, both non-neoplastic and neoplastic diseases. In addition, we have also addressed problems that remain to be investigated, in the hope of inspiring novel therapeutic strategies for diseases. [ABSTRACT FROM AUTHOR]

Anoikis-Related Genes (ARGs) lead to the organism manifesting resistance to anoikis and are associated with unfavorable prognostic outcomes across various malignancies.Therefore, it is crucial to identify the pivotal target genes related to anoikis in HCC.We found that ARGs were significantly correlated with prognosis and immune responses in HCC. The core gene, SPP1, notably promoted anoikis resistance and metastasis in HCC through both in vivo and in vitro studies. The PI3K-Akt-mTOR pathway played a critical role in anoikis suppression within HCC contexts. Our research unveiled SPP1's role in enhancing PKCα phosphorylation, which in turn activated the PI3K-Akt-mTOR cascade. Additionally, SPP1 was identified as a key regulator of MDSCs and Tregs migration, directly affecting their immunosuppressive capabilities.These findings indicate that in HCC, SPP1 promoted anoikis resistance and facilitated immune evasion by modulating MDSCs and Tregs. [ABSTRACT FROM AUTHOR]

Severe fever with thrombocytopenia syndrome virus (SFTSV) nonstructural protein (NSs) is an important viral virulence factor that sequesters multiple antiviral proteins into inclusion bodies to escape the antiviral innate immune response. However, the mechanism of the NSs restricting host innate immunity remains largely elusive. Here, we found that the NSs induced complete macroautophagy/autophagy by interacting with the CCD domain of BECN1, thereby promoting the formation of a BECN1-dependent autophagy initiation complex. Importantly, our data showed that the NSs sequestered antiviral proteins such as TBK1 into autophagic vesicles, and therefore promoted the degradation of TBK1 and other antiviral proteins. In addition, the 8A mutant of NSs reduced the induction of BECN1-dependent autophagy flux and degradation of antiviral immune proteins. In conclusion, our results indicated that SFTSV NSs sequesters antiviral proteins into autophagic vesicles for degradation and to escape antiviral immune responses. [ABSTRACT FROM AUTHOR]

AbstractThis study explores the prognostic value of immune escape-related genes in acute myeloid leukemia (AML) patients. Using TARGET_AML and GSE37642 datasets, we identified CEP55, DNAJC13, and EMC2 as significant prognostic indicators, with high transcript abundance correlating with poor outcomes. Consensus clustering divided patients into two groups, with Cluster 1 showing worse prognosis. A prognostic signature based on these genes stratified patients into high- and low-risk groups, with the high-risk group experiencing worse outcomes. The risk score was an independent prognostic factor. Functional analysis revealed that high-risk genes could promote cell cycle progression. The selected genes were strongly associated with immune cells, particularly mast cells and CD8+ T cells. This study enriches the prognostic evaluation system for AML and suggests a new therapeutic direction. [ABSTRACT FROM AUTHOR]

Triple‐negative breast cancer (TNBC) is the most malignant subtype of breast cancer. TP53, which has a mutation rate of ≈70%–80% in TNBC patients, plays oncogenic roles when mutated. However, whether circRNAs can exert their effects on TNBC through regulating mutant TP53 has not been well evaluated. In this study, circCFL1, which is highly expressed in TNBC cells and tissues and has prognostic potential is identified. Functionally, circCFL1 promoted the proliferation, metastasis and stemness of TNBC cells. Mechanistically, circCFL1 acted as a scaffold to enhance the interaction between HDAC1 and c‐Myc, further promoting the stability of c‐Myc via deacetylation‐mediated inhibition of K48‐linked ubiquitylation. Stably expressed c‐Myc further enhanced the expression of mutp53 in TNBC cells with TP53 mutations by directly binding to the promoter of TP53, which promoted the stemness of TNBC cells via activation of the p‐AKT/WIP/YAP/TAZ pathway. Moreover, circCFL1 can facilitate the immune escape of TNBC cells by promoting the expression of PD‐L1 and suppressing the antitumor immunity of CD8+ T cells. In conclusion, the results revealed that circCFL1 plays an oncogenic role by promoting the HDAC1/c‐Myc/mutp53 axis, which can serve as a potential diagnostic biomarker and therapeutic target for TNBC patients with TP53 mutations. [ABSTRACT FROM AUTHOR]

Hematological malignancies (HM) are common malignant tumors with high morbidity and mortality rates, and are malignant diseases that seriously affect human health, with chemotherapy prone to recurrence and toxic side effects. Therefore, the development of precise, effective, and safe targeted therapeutic agents has become a hotspot in the current research of antitumor technology. More and more studies have shown that the interaction of C–C chemokine ligand 17 (CCL17) and C–C chemokine ligand 22 (CCL22) with the receptor C–C chemokine receptor type 4 (CCR4) promotes the immune escape of tumors and is closely related to the occurrence, development, and prognosis of hematological tumors. In this regard, we present a review on the expression and role of the CCL17/CCL22-CCR4 axis in HM, including lymphoma, leukemia, and multiple myeloma, with the aim of providing latest ideas and directions for the diagnosis and treatment of HM. In addition, we discuss the role and related mechanisms of HM therapeutic agents targeting the CCL17/CCL22-CCR4 axis and the potential of humanized anti-CCR4 antibodies for the treatment of HM. [ABSTRACT FROM AUTHOR]

Programmed death‐ligand 1 (PD‐L1) is overexpressed in multiple cancers and critical for their immune escape. It has previously shown that the nuclear coactivator SRC‐1 promoted colorectal cancer (CRC) progression by enhancing CRC cell viability, yet its role in CRC immune escape is unclear. Here, we demonstrate that SRC‐1 is positively correlated with PD‐L1 in human CRC specimens. SRC‐1 deficiency significantly inhibits PD‐L1 expression in CRC cells and retards murine CRC growth in subcutaneous grafts by enhancing CRC immune escape via increasing tumor infiltration of CD8+ T cells. Genetic ablation of SRC‐1 in mice also decreases PD‐L1 expression in AOM/DSS‐induced murine CRC. These results suggest that tumor‐derived SRC‐1 promotes CRC immune escape by enhancing PD‐L1 expression. Mechanistically, SRC‐1 activated JAK‐STAT signaling by inhibiting SOCS1 expression and coactivated STAT3 and IRF1 to enhance PD‐L1 transcription as well as stabilized PD‐L1 protein by inhibiting proteasome‐dependent degradation mediated by speckle type POZ protein (SPOP). Pharmacological inhibition of SRC‐1 improved the antitumor effect of PD‐L1 antibody in both subcutaneous graft and AOM/DSS‐induced murine CRC models. Taken together, these findings highlight a crucial role of SRC‐1 in regulating PD‐L1 expression and targeting SRC‐1 in combination with PD‐L1 antibody immunotherapy may be an attractive strategy for CRC treatment. [ABSTRACT FROM AUTHOR]

Prostate cancer (PCa) is one of the most common male genitourinary system malignancies. Despite the significant benefits of anti-PD-L1 immune checkpoint inhibitor therapy in other cancers, the reasons for its poor therapeutic efficacy in prostate cancer (PCa) remain unclear.NDR1 plays an important role in innate immunity, but its role in tumor immunity and immunotherapy has not been investigated. The role of NDR1 in the immune microenvironment of PCa and the related mechanisms are unknown. Here, we found a positive correlation between NDR1 and PD-L1 expression in PCa. NDR1 significantly inhibits CD8 + T cell infiltration and function, thereby promoting immune escape in prostate cancer.More importantly, NDR1 inhibition significantly enhanced CD8 + T cell activation, which enhanced the therapeutic effect of anti-PD-L1. Mechanistic studies revealed that NDR1 inhibits ubiquitination-mediated PD-L1 degradation via the deubiquitinase USP10, upregulates PD-L1, and promotes PCa immune escape. Thus, our study suggests a unique PD-L1 regulatory mechanism underlying PCa immunotherapy failure. The significance of NDR1 in PCa immune escape and its mechanism of action were clarified, and combined NDR1/PD-L1 inhibition was suggested as an approach to boost PCa immunotherapy effectiveness. [ABSTRACT FROM AUTHOR]

The endoplasmic reticulum (ER) is a unique organelle responsible for protein synthesis and processing, lipid synthesis in eukaryotic cells, and the replication of many animal viruses is closely related to ER. A considerable number of viral proteins are synthesised during viral infection, resulting in the accumulation of unfolded and misfolded proteins in ER, which in turn induces endoplasmic reticulum stress (ERS). ERS further drives three signalling pathways (PERK, IRE1, and ATF6) of the cellular unfolded protein response (UPR) to respond to the ERS. In numerous studies, ERS has been shown to mediate autophagy, a highly conserved cellular degradation mechanism to maintain cellular homeostasis in eukaryotic cells, through the UPR to restore ER homeostasis. ERS-mediated autophagy is closely linked to the occurrence and development of numerous viral diseases in animals. Host cells can inhibit viral replication by regulating ERS-mediated autophagy, restoring the ER's normal physiological process. Conversely, many viruses have evolved strategies to exploit ERS-mediated autophagy to achieve immune escape. These strategies include the regulation of PERK-eIF2α-Beclin1, PERK-eIF2α-ATF4-ATG12, IRE1α-JNK-Beclin1, and other signalling pathways, which provide favourable conditions for the replication of animal viruses in host cells. The ERS-mediated autophagy pathway has become a hot topic in animal virological research. This article reviews the most recent research regarding the regulatory functions of ERS-mediated autophagy pathways in animal viral infections, emphasising the underlying mechanisms in the context of different viral infections. Furthermore, it considers the future direction and challenges in the development of ERS-mediated autophagy targeting strategies for combating animal viral diseases, which will contribute to unveiling their pathogenic mechanism from a new perspective and provide a scientific reference for the discovery and development of new antiviral drugs and preventive strategies. [ABSTRACT FROM AUTHOR]

Background: Cluster of differentiation 24 (CD24) is a highly glycosylated glycosylphosphatidylinositol (GPI)-anchored surface protein, expressed in various tumor cells, as a "don't eat me" signaling molecule in tumor immune. This study aimed to investigate the potential features of CD24 in pan-cancer. Methods: The correlations between 22 immune cells and CD24 expression were using TIMER analysis. R package "ESTIMATE" was used to predict the proportion of immune and stromal cells in pan-cancer. Spearman's correlation analysis was performed to evaluate the relationships between CD24 expression and immune checkpoints, chemokines, mismatch repair, tumor mutation burden and microsatellite instability, and qPCR and western blot were conducted to assess CD24 expression levels in liver hepatocellular carcinoma (LIHC). In addition, loss of function was performed for the biological evaluation of CD24 in LIHC. Results: CD24 expression was positively correlated with myeloid cells, including neutrophils and myeloid-derived suppressor cells, in various tumors, such as BLCA, HNSC-HPV, HNSC, KICH, KIRC, KIRP, TGCT, THCA, THYM, and UCEC. In contrast, anti-tumor NK cells and NKT cells showed a negative association with CD24 expression in BRCA-Her2, ESCA, HNSC-HPV, KIRC, THCA, and THYM. The top three tumors with the highest correlation between CD24 and ImmuneScore were TGCT, THCA, and SKCM. Functional enrichment analysis revealed CD24 expression was negatively associated with various immune-related pathways. Immune checkpoints and chemokines also exhibited inverse correlations with CD24 in CESC, CHOL, COAD, ESCA, READ, TGCT, and THCA. Additionally, CD24 was overexpressed in most tumors, with high CD24 expression in BRCA, LIHC, and CESC correlating with poor prognosis. The TIDE database indicated tumors with high CD24 expression, particularly melanoma, were less responsive to PD1/PD-L1 immunotherapy. Finally, CD24 knockdown resulted in impaired proliferation and cell cycle progression in LIHC. Conclusion: CD24 participates in regulation of immune infiltration, influences patient prognosis and serves as a potential tumor marker. [ABSTRACT FROM AUTHOR]

Cancer stem cells (CSCs) are a small group of cells found in tumors that have same self-renewing properties as nor‑ mal stem cells. In recent years, with continuous development of science and technology in various aspects, people's research on tumor diseases has been deepened. CSCs has been defined as a key factor in promoting tumor development, especially participating in pro‑ moting tumor recurrence, metastasis, chemotherapy resistance, etc. Currently, CD133 has become one of popular CSCs markers, and can be highly expressed in a variety of CSCs. CD133 is closely related to diagnosis of cancer diseases, and plays an important role in dignosis and drug targeting for gastric cancer, lung cancer, brain tumor, liver cancer, ovarian cancer and colorectal cancer. This article reviews structure, function, immune mechanism escape of CD133, signal pathway of CD133 in tumorigenesis, and correlation of CD133 with various tumors as well. [ABSTRACT FROM AUTHOR]

Objective：To investigate the effect and mechanism of miR-217 targeted regulation of extracellular signal-regulated kinase 2 (ERK2) expression on activity and immune escape of non-small cell lung cancer cells (NSCLC) . Methods：qRT-PCR was used to detect expression levels of miR-217 and ERK2 mRNA in NSCLC tissues, adjacent tissues, and HLF-1, A549 and HCC827 cell lines. Analyzed prognosis and survival status of NSCLC patients with different miR-217 expression level. Bioinformatics and dual luciferase gene reporting experiments were used to analyze the targeting relationship between miR-217 and ERK2. Cultivated NSCLC A549 cells and divided them into NC group, miR-217 inhibitor group, miR-217 mimic group, miR-217 mimic+ERK2 NC group and miR-217 mimic+ERK2 group. Except for the NC group without any treatment, all other groups were transfected with corresponding plasmids to analyze the proliferation activity and immune escape status of A549 cells in each group, and clarified the mechanism of action. Results：Compared with adjacent tissues, expression of miR-217 in NSCLC tissue was decreased, while expression of ERK2 mRNA was increased (P<0.05) . Compared with human normal lung fibroblast HLF-1 cell lines, expression of miR-217 in NSCLC cell lines A549 and HCC827 were decreased, while expression of ERK2 mRNA was increased (P<0.05) . Analysis of the relationship between miR-217 and prognosis of NSCLC patients based on Kaplan-Meier Plotter database showed that low expression of miR-217 was associated with poor prognosis of patients (HR=0.90, P=0.033) . Dual fluorescein reporter genes showed matching sequences between the 3'UTR regions of miR-217 and ERK2. miR-217 mimic fragment could inhibit ERK2-WT signal, but had no effect on ERK2-MUT. Compared with NC group, cell proliferation activity, PD-L1 and PD-L2 mRNA expression levels of miR-217 inhibitor group were inreased, while CD8+T cell activity was decreased, and cell proliferation activity, PD-L1 and PD-L2 mRNA expression levels of miR- 217 mimic group were decreased, while CD8+T cell activity was increased (P<0.05) . Compared with miR-217 mimic group, cell proliferation activity, CD8+T cell activity, PD-L1 and PD-L2 mRNA expression levels of miR-217 mimic+ERK2 NC group had no significant changes (P>0.05), cell proliferation activity, PD-L1 and PD-L2 mRNA expression levels of miR-217 mimic+ERK2 group were increased, while CD8+T cell activity was decreased (P<0.05) . Conclusion：Overexpression of miR-217 can reduce the activity of NSCLC cell A549, inhibit the expression of PD-L1, activate CD8+T cells in tumor microenvironment, and then inhibit immune escape, which may play a role by targeting ERK2. [ABSTRACT FROM AUTHOR]

Objective: To explore the mechanism of hepatitis B virus (HBV) inhibiting M1 macrophages to promote immune escape, and to provide targets and strategies for antiviral therapy. Methods: The human monocyte cell line THP-1 was induced into M1 macrophages with PMA+LPS+IFN-γ. Cell morphological changes and the expressions of CD68, CD86, HLA-DR and functional molecules IL-1β, IL-6, TNF-α in M1 macrophages were detected by flow cytometry and RT-qPCR to identify M1 macrophages. HBV stable replication cell line HepG2.2.15 were co-cultured with M1 macrophages, and the expression of HBV-DNA was detected by qPCR. The expression of CD68, CD86 and HLA-DR were detected by flow cytometry. The expressions of functional molecules TLR4, NLRP3, Caspase-1, pro-caspase-1, caspase-1 p20, IL-1β and IL-18 in M1 macrophages were determined by RT-qPCR and Western blot. Apoptosis rate was detected by flow cytometry, and the expression of apoptosis related protein cleaved-caspase-3 was determined by Western blot. Results: THP-1 was successfully induced to differentiate into M1 macrophages. M1 macrophages inhibited HBV replication (P<0.05). HBV inhibited the expressions of CD68, CD86 and HLA-DR in M1 macrophages（P<0.01). HBV inhibited the expressions of TLR4, NLRP3, Caspase-1, caspase-1 p20, IL-1β and IL-18 in M1 macrophages (P<0.01). HBV induced M1 macrophage apoptosis (P<0.05). Conclusion: HBV inhibits M1 macrophages and their functional molecules TLR4, NLRP3 and downstream factors, reduces the synthesis and secretion of inflammatory factors, induces apoptosis, and then promotes immune escape, resulting in the persistence and replication of HBV in the body. [ABSTRACT FROM AUTHOR]

The large T antigen (LT) of the Merkel cell polyomavirus (MCPyV) is crucial for Merkel cell carcinoma (MCC), a rare but very aggressive form of neuroendocrine skin cancer. The clonal integration of MCPyV DNA into the host genome is a signature event of this malignancy. The resulting expression of oncogenes, including the small T (sT) antigen and a truncated form of the LT (truncLT), directly contribute to carcinogenesis. The truncation of the C-terminus of LT prevents the virus from replicating due to the loss of the origin binding domain (OBD) and the helicase domain. This precludes cytopathic effects that would lead to DNA damage and ultimately cell death. At the same time, the LxCxE motif in the N-terminus is retained, allowing truncLT to bind the retinoblastoma protein (pRb), a cellular tumor suppressor. The continuously inactivated pRb promotes cell proliferation and tumor development. truncLT exerts several classical functions of an oncogene: altering the host cell cycle, suppressing innate immune responses to viral DNA, causing immune escape, and shifting metabolism in favor of cancer cells. Given its central role in MCC, the LT is a major target for therapeutic interventions with novel approaches, such as immune checkpoint inhibition, T cell-based immunotherapy, and cancer vaccines. [ABSTRACT FROM AUTHOR]

The most recent wave of SARS-CoV-2 Omicron variants descending from BA.2 and BA.2.86 exhibited improved viral growth and fitness due to convergent evolution of functional hotspots. These hotspots operate in tandem to optimize both receptor binding for effective infection and immune evasion efficiency, thereby maintaining overall viral fitness. The lack of molecular details on structure, dynamics and binding energetics of the latest FLiRT and FLuQE variants with the ACE2 receptor and antibodies provides a considerable challenge that is explored in this study. We combined AlphaFold2-based atomistic predictions of structures and conformational ensembles of the SARS-CoV-2 spike complexes with the host receptor ACE2 for the most dominant Omicron variants JN.1, KP.1, KP.2 and KP.3 to examine the mechanisms underlying the role of convergent evolution hotspots in balancing ACE2 binding and antibody evasion. Using the ensemble-based mutational scanning of the spike protein residues and computations of binding affinities, we identified binding energy hotspots and characterized the molecular basis underlying epistatic couplings between convergent mutational hotspots. The results suggested the existence of epistatic interactions between convergent mutational sites at L455, F456, Q493 positions that protect and restore ACE2-binding affinity while conferring beneficial immune escape. To examine immune escape mechanisms, we performed structure-based mutational profiling of the spike protein binding with several classes of antibodies that displayed impaired neutralization against BA.2.86, JN.1, KP.2 and KP.3. The results confirmed the experimental data that JN.1, KP.2 and KP.3 harboring the L455S and F456L mutations can significantly impair the neutralizing activity of class 1 monoclonal antibodies, while the epistatic effects mediated by F456L can facilitate the subsequent convergence of Q493E changes to rescue ACE2 binding. Structural and energetic analysis provided a rationale to the experimental results showing that BD55-5840 and BD55-5514 antibodies that bind to different binding epitopes can retain neutralizing efficacy against all examined variants BA.2.86, JN.1, KP.2 and KP.3. The results support the notion that evolution of Omicron variants may favor emergence of lineages with beneficial combinations of mutations involving mediators of epistatic couplings that control balance of high ACE2 affinity and immune evasion. [ABSTRACT FROM AUTHOR]

Bladder cancer is a highly prevalent malignancy. Asiaticoside (AC), a triterpenoid derivative, exhibits antitumor effect on different tumors. This study aimed to explore the role and mechanism of AC on bladder cancer. J82 and T24 cells were treated with AC and/or propofol, and nude mice were subcutaneously administrated with T24 cells. The effect and mechanism of AC and/or propofol were explored by cell counting kit‐8, transwell, flow cytometry, enzyme‐linked immunosorbent assay, immunohistochemistry and western blot assays both in vitro and in vivo. Cell viability of J82 and T24 cells was inhibited by AC with a IC50 value of 2.43 μM and 2.16 μM, and by propofol with a IC50 value of 42.51 μM and 48.37 μM, respectively. AC or propofol alone decreased cell proliferation, invasion, and immune escape with the increased ferroptosis, as well as downregulating the level of the PI3K/AKT pathway in both animal and cell experiments. The effect of propofol on the above‐mentioned indicators was further enhanced with the co‐treatment of AC in vitro and in vivo. Taken together, AC promoted the ameliorative effect of propofol on bladder cancer involved in PI3K/AKT pathway. [ABSTRACT FROM AUTHOR]

Introduction: The occurrence and progression of lung adenocarcinoma (LUAD) impair T-cell immune responses, causing immune escape and subsequently affecting the efficacy of immunotherapy in patients. Aurora kinase A (AURKA) is upregulated in varying cancers, but its role in LUAD immune escape is elusive. This work attempted to explore molecular mechanisms of AURKA regulation in LUAD immune escape. Methods: Through bioinformatics analysis, AURKA level in LUAD was evaluated, and potential upstream transcription factors of AURKA were predicted using hTFtarget. ETS variant transcription factor 4 (ETV4) expression in LUAD was analyzed through The Cancer Genome Atlas. Pearson's correlation analysis was then utilized to test the correlation between AURKA and ETV4. Interaction and binding between AURKA and ETV4 were validated through dual-luciferase assay and chromatin immunoprecipitation. Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) tested relative mRNA expression of AURKA and ETV4 in LUAD cells, cell counting kit-8 assayed cell viability, and Western blot analysis was conducted to determine the protein level of programmed death-ligand 1 (PD-L1). Coculture of LUAD cells with activated CD8+ T cells was carried out, and an LDH assay was used to assess the cytotoxicity of CD8+ T cells against LUAD cells. Interferon-γ (IFN-γ), interleukin-2 (IL-2), and tumor necrosis factor-α (TNF-α) levels in the coculture system were assessed by enzyme-linked immunosorbent assay (ELISA). Western blot assessed protein levels of JAK2, p-JAK2, STAT3, and p-STAT3. Results: Compared to normal tissues, AURKA and ETV4 were upregulated in tumor tissues, and AURKA presented a negative association with CD8+ T-cell immune infiltration but a positive association with PD-L1. qRT-PCR unveiled significantly upregulated mRNA of AURKA and ETV4 in LUAD cells compared to normal lung epithelial cells. Knockdown of AURKA significantly decreased cell viability and PD-L1 protein level in LUAD cells, enhanced cytotoxicity of CD8+ T cells against LUAD cells and IFN-γ, IL-2, and TNF-α expression, while overexpression of AURKA yielded opposite results. Furthermore, the knockdown of ETV4 could reverse the oncogenic characteristics of cells caused by AURKA overexpression. Conclusion: Our study illustrated that ETV4/AURKA axis promoted PD-L1 expression, suppressed CD8+ T-cell activity, and mediated immune escape in LUAD by regulating the JAK2/STAT3 signaling pathway. [ABSTRACT FROM AUTHOR]

It is urgent to explore factors affecting immunotherapy efficacy to benefit non‐small cell lung cancer (NSCLC) patient survival. Bioinformatics predicted genes associated with programmed cell death ligand 1 (PD‐L1) expression and analysed phospholipase A2 group IID (PLA2G2D) expression in NSCLC. BODIPY 493/503 dye staining and kits detected lipids, triglycerides, and phospholipids in H1299 cells, respectively. Extracellular vesicles (EVs) were extracted for morphology and size assessment using electron microscopy. Western blot assayed CD9, CD63, HSP90, EVs‐PD‐L1, PD‐L1, and PLA2G2D expression. CCK‐8, LDH, and ELISA tested proliferation and toxicity of CD8+ T cells, interleukin‐2, and interferon‐gamma secretion, respectively. PLA2G2D, PD‐L1, and Ki67 expression was detected by immunohistochemistry. Immunofluorescence assayed PLA2G2D localisation and CD8+ T cell content. Flow cytometry assessed PD‐L1 and CD8 expression. In NSCLC, upregulated EVs‐PD‐L1 and clinical characteristics showed a strong correlation. H1299 cells with overexpression PD‐L1 significantly reduced proliferation, toxicity of CD8+ T cells, and interleukin‐2 and interferon‐gamma levels. Bioinformatics revealed positive correlations between PLA2G2D and overexpressed PD‐L1. PLA2G2D was expressed in macrophages and dendritic cells in NSCLC tissue. Overexpression PLA2G2D (oe‐PLA2G2D) increased lipids, triglycerides, and phospholipids contents in H1299 cells. oe‐PLA2G2D significantly reduced proliferation, toxicity of CD8+ T cells, and interleukin‐2 and interferon‐gamma levels. si‐PD‐L1 restored inhibition of oe‐PLA2G2D on CD8+ T cells. oe‐PLA2G2D significantly increased mice tumour volume and weight, upregulated expression of blood EVs‐PD‐L1 and tissue PD‐L1, PLA2G2D, Ki67, and decreased CD8+ T cell content. PLA2G2D facilitated immune escape in NSCLC by regulating CD8+ T cell immune function by upregulating EVs‐PD‐L1. [ABSTRACT FROM AUTHOR]

In the field of cancer therapy, inhibiting autophagy has emerged as a promising strategy. However, pharmacological disruption of autophagy can lead to the upregulation of programmed death-ligand 1 (PD-L1), enabling tumor immune evasion. To address this issue, we developed innovative ROS-responsive cationic poly(ethylene imine) (PEI) nanogels using selenol chemistry-mediated multicomponent reaction (MCR) technology. This procedure involved simple mixing of low-molecular-weight PEI (LMW PEI), γ-selenobutylacetone (γ-SBL), and poly(ethylene glycol) methacrylate (PEGMA). Through high-throughput screening, we constructed a library of AxSeyOz nanogels and identified the optimized A1.8Se3O0.5/siPD-L1 nanogels, which exhibited a size of approximately 200 nm, excellent colloidal stability, and the most effective PD-L1 silencing efficacy. These nanogels demonstrated enhanced uptake by tumor cells, excellent oxidative degradation ability, and inhibited autophagy by alkalinizing lysosomes. The A1.8Se3O0.5/siPD-L1 nanogels significantly downregulated PD-L1 expression and increased the expression of major histocompatibility complex class I (MHC-I), resulting in robust proliferation of specific CD8+ T cells and a decrease in MC38 tumor growth. As a result, the A1.8Se3O0.5/siPD-L1 nanogels inhibited tumor growth through self-inhibition of autophagy, upregulation of MHC-I, and downregulation of PD-L1. Designed with dynamic diselenide bonds, the A1.8Se3O0.5/siPD-L1 nanogels showed synergistic antitumor efficacy through self-inhibition of autophagy and prevention of immune escape.

Abstract Immune cell therapy based on chimeric antigen receptor (CAR) technology platform has been greatly developed. The types of CAR immune cell therapy have expanded from T cells to innate immune cells such as NK cells and macrophages, and the diseases treated have expanded from hematological malignancies to non-tumor fields such as infectious diseases and autoimmune diseases. Among them, CAR-T and CAR-NK therapy have observed examples of rapid remission in approved clinical trials, but the efficacy is unstable and plagued by tumor resistance. Trogocytosis is a special phenomenon of intercellular molecular transfer that is common in the immune system and is achieved by recipient cells through acquisition and internalization of donor cell-derived molecules and mediates immune effects. Recently, a novel short-term drug resistance mechanism based on trogocytosis has been proposed, and the bidirectional molecular exchange between CAR immune cells and tumor cells triggered by trogocytosis partially explains the long-term relapse phenomenon after treatment with CAR immune cells. In this review, we summarize the research progress of trogocytosis in CAR immunotherapy, discuss the influencing factors of trogocytosis and its direct and indirect interference with CAR immune cells and emphasize that the interference of trogocytosis can further release the potential of CAR immune cell therapy.

Recent studies have identified that metabolic reprogramming in lung adenocarcinoma cells, particularly lactate metabolism disorders, plays a crucial role in tumor development and immune therapy response. The accumulation of lactic acid not only provides energy support for the proliferation of tumor cells but also affects the function of immune cells by changing the tumor microenvironment, thereby promoting immune escape. Immunotherapy, especially the application of immune checkpoint inhibitors, has become an important strategy for treating lung adenocarcinoma. However, lactate metabolism disorders might affect the efficacy of immunotherapy, leading to resistance in some patients. Therefore, a thorough understanding of the mechanisms of lactic acid metabolism in lung adenocarcinoma and its impact on the response to immunotherapy is essential for developing new therapeutic strategies and improving the efficacy of immunotherapy. This review summarizes the role of lactate metabolism disorders in the development and immunotherapy of lung adenocarcinoma, discusses the potential role of lactic acid metabolism-related genes and pathways in lung adenocarcinoma, and explores the progress in therapeutic strategies targeting lactic acid metabolism regulation. This work aims to provide new insights for the treatment of lung adenocarcinoma.

Abstract Pseudorabies virus (PRV) can establish lifelong latent infection in peripheral nervous ganglion, and persistent infections in peripheral blood lymphocytes. Establishing an infection in the lymphocytes does not only enable the PRV to escape host immune surveillance but pass through the placental barrier, leading to fetal death and abortion. Due to the pathogenicity of the PRV, it poses a huge challenge in its prevention and control. The PRV escapes host immunity through downregulation of swine leukocyte antigen class I (SLA I) molecules on infected cells. However, data on the molecular mechanisms of the SLA I suppression remains scant. Here, in order to verify the effect of candidate proteins PRV pUL44 and pUS6 on PRV immune escape related molecules SLA I and peptide loading complex (PLC), we detected the expression of SLA I and PLC components after expressing PRV pUL44 and pUS6. The effects of pUS6 and pUL44 on SLA I and PLC were analyzed by qRT-PCR and Western blot at mRNA and protein level, respectively. Cells expressing pUS6 or pUL44 genes showed a significantly suppressed expression of surface and total SLA I molecules. In addition, unlike UL44, the US6 gene was shown to downregulate the transporter associated with antigen processing 1 (TAP1), TAP2 and Tapasin molecules. The results show that PRV pUS6 may participate in virus immune escape by directly regulating the SLA I, TAP dimer and Tapasin molecules, thus blocking the transportation of TAP-bound peptides to the ER to bind SLA I molecules. We provide a theoretical basis on the mechanism of TAP mediated immune escape by the PRV.

Abstract Background Cluster of differentiation 24 (CD24) is a highly glycosylated glycosylphosphatidylinositol (GPI)-anchored surface protein, expressed in various tumor cells, as a "don't eat me" signaling molecule in tumor immune. This study aimed to investigate the potential features of CD24 in pan-cancer. Methods The correlations between 22 immune cells and CD24 expression were using TIMER analysis. R package “ESTIMATE” was used to predict the proportion of immune and stromal cells in pan-cancer. Spearman's correlation analysis was performed to evaluate the relationships between CD24 expression and immune checkpoints, chemokines, mismatch repair, tumor mutation burden and microsatellite instability, and qPCR and western blot were conducted to assess CD24 expression levels in liver hepatocellular carcinoma (LIHC). In addition, loss of function was performed for the biological evaluation of CD24 in LIHC. Results CD24 expression was positively correlated with myeloid cells, including neutrophils and myeloid-derived suppressor cells, in various tumors, such as BLCA, HNSC-HPV, HNSC, KICH, KIRC, KIRP, TGCT, THCA, THYM, and UCEC. In contrast, anti-tumor NK cells and NKT cells showed a negative association with CD24 expression in BRCA-Her2, ESCA, HNSC-HPV, KIRC, THCA, and THYM. The top three tumors with the highest correlation between CD24 and ImmuneScore were TGCT, THCA, and SKCM. Functional enrichment analysis revealed CD24 expression was negatively associated with various immune-related pathways. Immune checkpoints and chemokines also exhibited inverse correlations with CD24 in CESC, CHOL, COAD, ESCA, READ, TGCT, and THCA. Additionally, CD24 was overexpressed in most tumors, with high CD24 expression in BRCA, LIHC, and CESC correlating with poor prognosis. The TIDE database indicated tumors with high CD24 expression, particularly melanoma, were less responsive to PD1/PD-L1 immunotherapy. Finally, CD24 knockdown resulted in impaired proliferation and cell cycle progression in LIHC. Conclusion CD24 participates in regulation of immune infiltration, influences patient prognosis and serves as a potential tumor marker.

Abstract Hematological malignancies (HM) are common malignant tumors with high morbidity and mortality rates, and are malignant diseases that seriously affect human health, with chemotherapy prone to recurrence and toxic side effects. Therefore, the development of precise, effective, and safe targeted therapeutic agents has become a hotspot in the current research of antitumor technology. More and more studies have shown that the interaction of C–C chemokine ligand 17 (CCL17) and C–C chemokine ligand 22 (CCL22) with the receptor C–C chemokine receptor type 4 (CCR4) promotes the immune escape of tumors and is closely related to the occurrence, development, and prognosis of hematological tumors. In this regard, we present a review on the expression and role of the CCL17/CCL22-CCR4 axis in HM, including lymphoma, leukemia, and multiple myeloma, with the aim of providing latest ideas and directions for the diagnosis and treatment of HM. In addition, we discuss the role and related mechanisms of HM therapeutic agents targeting the CCL17/CCL22-CCR4 axis and the potential of humanized anti-CCR4 antibodies for the treatment of HM.

Abstract Prostate cancer (PCa) is one of the most common male genitourinary system malignancies. Despite the significant benefits of anti-PD-L1 immune checkpoint inhibitor therapy in other cancers, the reasons for its poor therapeutic efficacy in prostate cancer (PCa) remain unclear.NDR1 plays an important role in innate immunity, but its role in tumor immunity and immunotherapy has not been investigated. The role of NDR1 in the immune microenvironment of PCa and the related mechanisms are unknown. Here, we found a positive correlation between NDR1 and PD-L1 expression in PCa. NDR1 significantly inhibits CD8 + T cell infiltration and function, thereby promoting immune escape in prostate cancer.More importantly, NDR1 inhibition significantly enhanced CD8 + T cell activation, which enhanced the therapeutic effect of anti-PD-L1. Mechanistic studies revealed that NDR1 inhibits ubiquitination-mediated PD-L1 degradation via the deubiquitinase USP10, upregulates PD-L1, and promotes PCa immune escape. Thus, our study suggests a unique PD-L1 regulatory mechanism underlying PCa immunotherapy failure. The significance of NDR1 in PCa immune escape and its mechanism of action were clarified, and combined NDR1/PD-L1 inhibition was suggested as an approach to boost PCa immunotherapy effectiveness. Graphical Abstract

Abstract The endoplasmic reticulum (ER) is a unique organelle responsible for protein synthesis and processing, lipid synthesis in eukaryotic cells, and the replication of many animal viruses is closely related to ER. A considerable number of viral proteins are synthesised during viral infection, resulting in the accumulation of unfolded and misfolded proteins in ER, which in turn induces endoplasmic reticulum stress (ERS). ERS further drives three signalling pathways (PERK, IRE1, and ATF6) of the cellular unfolded protein response (UPR) to respond to the ERS. In numerous studies, ERS has been shown to mediate autophagy, a highly conserved cellular degradation mechanism to maintain cellular homeostasis in eukaryotic cells, through the UPR to restore ER homeostasis. ERS-mediated autophagy is closely linked to the occurrence and development of numerous viral diseases in animals. Host cells can inhibit viral replication by regulating ERS-mediated autophagy, restoring the ER's normal physiological process. Conversely, many viruses have evolved strategies to exploit ERS-mediated autophagy to achieve immune escape. These strategies include the regulation of PERK-eIF2α-Beclin1, PERK-eIF2α-ATF4-ATG12, IRE1α-JNK-Beclin1, and other signalling pathways, which provide favourable conditions for the replication of animal viruses in host cells. The ERS-mediated autophagy pathway has become a hot topic in animal virological research. This article reviews the most recent research regarding the regulatory functions of ERS-mediated autophagy pathways in animal viral infections, emphasising the underlying mechanisms in the context of different viral infections. Furthermore, it considers the future direction and challenges in the development of ERS-mediated autophagy targeting strategies for combating animal viral diseases, which will contribute to unveiling their pathogenic mechanism from a new perspective and provide a scientific reference for the discovery and development of new antiviral drugs and preventive strategies.

Cancer immunotherapies have greatly changed the prospects for the therapy of many malignancies, including colon cancer. Macrophages as the effectors of cancer immunotherapy provide considerable promise for cancer treatment. Prolyl 4-hydroxylase subunit alpha 3 (P4HA3) plays a cancer-promoting role in a variety of cancers, including colon cancer. In the present work, we provided evidence for the first time that P4HA3 promoted colon cancer cell escape from macrophage phagocytosis, and preliminarily explored its possible molecular mechanism. Immunohistochemistry was used to detect the expression of P4HA3 in tissues. Bioinformatics methods were used to analyze the tumor public databases (including TCGA database and GEO database). Macrophage phagocytosis assay and flow cytometric analysis were used to detect the phagocytic capacity of macrophages. Western blot and qRT-PCR were used to detect the expression of related markers (such as P4HA3, CD47, CD24, IL-34, and M-CSF). First, we found that P4HA3 was significantly and highly expressed in both colon cancer tissues and cells, and that P4HA3 had a positive correlation with lymph node metastasis, Dukes stage and also strongly correlated with poorer survival. Subsequently, we found that P4HA3 was strongly associated with the macrophage infiltration level in colon cancer. Immediately we also found that decreasing P4HA3 expression promoted macrophage phagocytosis in colon cancer cells, whereas P4HA3 overexpression produced the opposite effect. Finally, we demonstrated that P4HA3 promoted the expression of cluster of differentiation 47 (CD47) in colon cancer cells. Moreover, P4HA3 caused colon cancer cells to secrete Interleukin 34 (IL34) and Macrophage colony stimulating factor (M-CSF), which further induced macrophages to differentiate to M2 type and thereby contributed to the progression of colon cancer. We have demonstrated that P4HA3-driven CD47 overexpression may act as an escape mechanism, causing colon cancer cells to evade phagocytosis from macrophages. [ABSTRACT FROM AUTHOR]

Immunotherapy has become the cornerstone of current malignant tumor treatment. However, the response of different patients to immunotherapy is highly heterogeneous, and not all patients can benefit from it. There is an urgent need to find biomarkers that can effectively predict the efficacy of immunotherapy. C-C chemokine ligand 4 (CCL4) is a cytokine, belonging to the inflammatory CCL subfamily. It is mainly secreted by immune cells and tumor cells and shows low or no expression in normal tissues but abnormally high expression in various malignant tumor tissues. After binding to CCL4 and its receptor C-C chemokine receptor type 5 (CCR5), it can recruit and mediate immune cell migration, destroy the stability of the tumor microenvironment (TME), participate in carcinogenesis and promote the development of tumors. In the tumor immune microenvironment, CCL4 can mediate and recruit the directed migration of key immune cells such as monocytes, macrophages, natural killer (NK) cells, and T cells, which makes it a potentially important element affecting the efficacy of immunotherapy and has specific value. This paper reviews the research progresses of CCL4's effects on immune escape in TME, in order to provide clues and references for basic research and clinical diagnosis and treatment.

Abstract SHC1 plays a crucial regulatory role in various tumors, but its significance in predicting prognosis and immune response in clear cell renal cell carcinoma (ccRCC) is yet to be determined. In this study, we conducted a bioinformatics analysis of SHC1 expression, prognosis, and immunological functions in ccRCC using multiple databases. The association between SHC1 and immune infiltration, immune escape, and immunotherapy in ccRCC was systematically established. In addition, we validated our results by western blot of tumor and adjacent-tumor samples from nine ccRCC patients, as well as three renal carcinoma cell lines compared to a normal renal cell line. Our analysis revealed that the mRNA expression level of SHC1 in ccRCC tissues is significantly higher than that in normal tissues. Consistently, western blot experiment showed ccRCC tissues and cell lines exhibit higher protein levels that normal tissues and cell lines. Importantly, patients with low expression of SHC1 demonstrated a higher survival rate, indicating that SHC1 could serve as an independent prognostic factor for predicting survival in ccRCC. Additionally, high expression of SHC1 was associated with increased severe immune cell infiltration, enhanced immune escape, and higher immunotherapy scores. Hence, SHC1 emerges as a novel and easily detectable biomarker for predicting clinical outcomes, immune escape, and immunotherapy response in patients with ccRCC.

Abstract 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.

Abstract Nasopharyngeal carcinoma (NPC) is a malignant tumor of epithelial origin in head and neck with high incidence rate in South China, Southeast Asia and North Africa. The intervention of tumor-associated macrophages (Mφs) (TAMs)-mediated immunosuppression is a potential therapeutic strategy against tumor metastasis, but the exact mechanisms of TAM-mediated immunosuppression in nasopharyngeal carcinoma are unclear. Furthermore, how TAM affects the occurrence and development of nasopharyngeal carcinoma through metabolism is rarely involved. In this work, we revealed that NPC cells promoted M2-type Mφ polarization and elevated itaconic acid (ITA) release. Also, TAMs facilitated NPC cell proliferation, migration, and invasion through immune response gene 1 (IRG1)-catalyzed ITA production. Then, IRG1-mediated ITA production in TAMs repressed the killing of CD8+ T cells, induced M2-type polarization of TAMs, and reduced the phagocytosis of TAMs. Moreover, we demonstrated ITA played a tumor immunosuppressive role by binding and dampening ten-eleven translocation-2 (TET2) expression. Finally, we proved that ITA promotes NPC growth by facilitating immune escape in CD34+ hematopoietic stem cell humanized mice. In Conclusion, TAM-derived ITA facilitated NPC progression by enhancing immune escape through targeting TET2, highlighting that interfering with the metabolic pathway of ITA may be a potential strategy for NPC treatment.

Abstract Background Reticuloendotheliosis virus (REV), a member of the family Retroviridae, is a hot area of research, and a previous study showed that exosomes purified from REV-positive semen were not blocked by REV-specific neutralizing antibodies and established productive infections. Methods To further verify the infectivity of exosomes from REV-infected cells, we isolated and purified exosomes from REV-infected DF-1 cells and identified them using Western blot and a transmission electron microscope. We then inoculated 7-day-old embryonated eggs, 1-day-old chicks and 23-week-old hens with and without antibody treatment. REV was administered simultaneously as a control. Results In the absence of antibodies, the results indicated that REV-exosomes and REV could infect chicks, resulting in viremia and viral shedding, compared with the infection caused by REV, REV-exosomes reduced the hatching rate and increased mortality after hatching, causing severe growth inhibition and immune organ damage in 1-day-old chicks; both REV and REV-exosomes also could infect hens, however, lead to transient infection. In the presence of antibodies, REV-exosomes were not blocked by REV-specific neutralizing antibodies and infected 7-day-old embryonated eggs. However, REV could not infect 1-day-old chicks and 23-week-old hens. Conclusion In this study, we compared the infectious ability of REV-exosomes and REV, REV-exosomes could escape from REV-specific neutralizing antibodies in embryonated eggs, providing new insights into the immune escape mechanism of REV.

Abstract Background Melanoma progression is based on a close interaction between cancer cells and immune cells in the tumor microenvironment (TME). Thus, a better understanding of the mechanisms controlling TME dynamics and composition will help improve the management of this dismal disease. Work from our and other groups has reported the requirement of an active Hedgehog-GLI (HH-GLI) signaling for melanoma growth and stemness. However, the role of the downstream GLI1 transcription factor in melanoma TME remains largely unexplored. Methods The immune-modulatory activity of GLI1 was evaluated in a syngeneic B16F10 melanoma mouse model assessing immune populations by flow cytometry. Murine polymorphonuclear myeloid-derived suppressor cells (PMN-MDSCs) were differentiated from bone marrow cells and their immunosuppressive ability was assessed by inhibition of T cells. Conditioned media (CM) from GLI1-overexpressing mouse melanoma cells was used to culture PMN-MDSCs, and the effects of CM were evaluated by Transwell invasion assay and T cell inhibition. Cytokine array analysis, qPCR and chromatin immunoprecipitation were performed to explore the regulation of CX3CL1 expression by GLI1. Human monocyte-derived dendritic cells (moDCs) were cultured in CM from GLI1-silenced patient-derived melanoma cells to assess their activation and recruitment. Blocking antibodies anti-CX3CL1, anti-CCL7 and anti-CXCL8 were used for in vitro functional assays. Results Melanoma cell-intrinsic activation of GLI1 promotes changes in the infiltration of immune cells, leading to accumulation of immunosuppressive PMN-MDSCs and regulatory T cells, and to decreased infiltration of dendric cells (DCs), CD8 + and CD4 + T cells in the TME. In addition, we show that ectopic expression of GLI1 in melanoma cells enables PMN-MDSC expansion and recruitment, and increases their ability to inhibit T cells. The chemokine CX3CL1, a direct transcriptional target of GLI1, contributes to PMN-MDSC expansion and recruitment. Finally, silencing of GLI1 in patient-derived melanoma cells promotes the activation of human monocyte-derived dendritic cells (moDCs), increasing cytoskeleton remodeling and invasion ability. This phenotype is partially prevented by blocking the chemokine CCL7, but not CXCL8. Conclusion Our findings highlight the relevance of tumor-derived GLI1 in promoting an immune-suppressive TME, which allows melanoma cells to evade the immune system, and pave the way for the design of new combination treatments targeting GLI1.

Abstract Background Radioresistance and immune escape are crucial reasons for unsatisfactory therapeutic effects of glioblastoma (GBM). Although triggering receptor expressed on myeloid cells-2 (TREM2) involved in forming immunosuppressive microenvironment, but the underlying mechanism and its roles in mediating cancer radioresistance remain unclear, moreover, the efficient delivery of drugs targeting TREM2 to GBM encounters serious challenges. Hence, this study aimed to elucidate the effect and mechanisms of targeted TREM2 silencing on reversing the radioresistance and immune escape of GBM aided by a glutathione-responsive biomimetic nanoparticle (NP) platform. Methods Radioresistant GBM cell lines and TREM2 stable knockdown GBM cell lines were firstly established. RNA sequencing, colony formation assay, western blot, enzyme-linked immunosorbent assay and co-immunoprecipitation assay were used to detect the molecular mechanisms of TREM2 in regulating the radioresistance and immune escape of GBM. The glutathione-responsive biomimetic NP, angiopep-2 (A2)- cell membrane (CM)-NP/siTREM2/spam1, was then constructed to triply and targeted inhibit TREM2 for in vivo study. Orthotopic GBM-bearing mouse models were established to evaluate the anti-GBM effect of TREM2 inhibition, multiplex immunofluorescence assay was conducted to detect the infiltration of immune cells. Results TREM2 was a regulator in accelerating the radioresistance and immune escape of GBM through participating in DNA damage repair and forming a positive feedback loop with high mobility group box 1 (HMGB1) to cascade the activation of Toll-like receptor 4 (TLR4)/protein kinase B (Akt) signaling. A2-CM-NP/siTREM2/spam1 was successfully synthesized with excellent passive targeting, active targeting and homologous targeting, and the in vivo results exhibited its remarkable anti-GBM therapeutic effect through promoting the infiltration of type 1 helper T cells and CD8+T cells, reducing the infiltration of type 2 helper T cells and regulatory T cells, repolarizing macrophages to M1-type, and decreasing the secretion of pro-tumor and immunosuppressive cytokines. Conclusions Targeting TREM2 therapy is a promising avenue for optimizing radiotherapy and immunotherapy to improve the prognosis of GBM patients.

Abstract Background Circular RNAs (circRNAs) have been implicated in the development and progression of gastric cancer (GC). However, it remains unclear whether dysregulated circRNA affects immune escape and the efficacy of immunotherapy in GC. Our aim is to investigate the molecular mechanism of circRNA affecting GC immunotherapy and identify effective molecular therapeutic targets. Methods The differential expression profile of circRNAs was established through circRNA sequencing, comparing three paired GC tissues with their adjacent non-cancerous gastric tissues. The expression level of circRHBDD1 in GC tissues was then assessed using quantitative reverse transcription polymerase chain reaction (qRT-PCR). The biological characteristics of circRHBDD1 were verified through a series of experiments, including agarose gel electrophoresis assays, RNase R treatment, and actinomycin D experiments. The prognostic value of circRHBDD1 in GC was evaluated by conducting both univariate and multivariate survival analyses. Furthermore, loss- and gain-of-function approaches were utilized to investigate the impact of circRHBDD1 on GC immune escape. RNA-sequencing, immunoprecipitation, flow cytometry, and methylated RNA immunoprecipitation (meRIP) analysis were performed to elucidate the underlying molecular mechanisms. Results We discovered that circRHBDD1 exhibited remarkably high expression levels in GC tissues and cell lines. Notably, the high expression of circRHBDD1 was significantly correlated with poor overall survival and disease-free survival among GC patients. Both in vitro and in vivo experiments revealed that circRHBDD1 upregulated the expression of PD-L1 and impeded the infiltration of CD8+ T cells. Further, we found that circRHBDD1 binds to IGF2BP2, disrupting the interaction between E3 ligase TRIM25 and IGF2BP2, and ultimately inhibiting IGF2BP2 ubiquitination and degradation. Intriguingly, IGF2BP2 enhances PD-L1 mRNA stability through m6A modification. Additionally, we developed Poly (lactide-co-glycolic acid) (PLGA)-Polyethylene glycol (PEG)-based nanoparticles loaded with circRHBDD1 siRNA. In vivo experiments validated that the combination of PLGA-PEG(si-circRHBDD1) and anti-PD-1 offers a safe and efficacious nano-drug regimen for cancer immunotherapy. Conclusion Our results demonstrated that circRHBDD1 promoted GC immune escape by upregulating the expression of PD-L1 and reprogramming T cell-mediated immune response. Inhibition of circRHBDD1 expression could potentially enhance the response of GC patients to immunotherapy, thus improving treatment outcomes. Additionally, the development of a nanodrug delivery system provides a feasible approach for future clinical applications.

Abstract Background Patients with lung adenocarcinoma (LUAD) have a low response rate to immune checkpoint blockade. It is highly important to explore the tumor immune escape mechanism of LUAD patients and expand the population of patients who may benefit from immunotherapy. Methods Based on 954 bulk RNA-seq data of LUAD patients and 15 single-cell RNA-seq data, the relationships between tumor immune dysfunction and exclusion (TIDE) scores and survival prognosis in each patient were calculated and evaluated, and the immune escape mechanism affecting the independent prognosis of LUAD patients was identified. Functional enrichment analysis explored the antitumour immune response and biological behavior of tumor cells among different LUAD groups. Single-cell annotation and pseudotemporal analysis were used to explore the target molecules and immune escape mechanisms of LUAD. Results Myeloid-derived suppressor cells (MDSCs) and IRF8 were identified as risk and protective factors for the independent prognosis of LUAD patients, respectively. In the tumor microenvironment of patients with high infiltration of MDSCs, the antitumor immune response is significantly suppressed, while tumor cell division, proliferation, and distant metastasis are significantly enhanced. Single-cell RNA-seq analysis revealed that IRF8 is an important regulator of MDSC differentiation in LUAD myeloid cells. In addition, IRF8 may regulate the differentiation of MDSCs through the IL6-JAK-STAT3 signalling pathway. Conclusions IRF8 deficiency impairs the normal development of LUAD myeloid cells and induces their differentiation into MDSCs, thereby accelerating the immune escape of LUAD cells. IRF8-targeted activation to inhibit the formation of MDSCs may be a new target for immunotherapy in LUAD.

Xiaorong Qin, Hongyan Li, Jianqiu Wu, Weiyan Tang, Wenjuan Li, Kejin Li Department of Internal Medicine, Jiangsu Cancer Hospital, Jiangsu Institute of Cancer Research, The Affiliated Cancer Hospital of Nanjing Medical University, Nanjing, Jiangsu, 210009, People’s Republic of ChinaCorrespondence: Hongyan Li, Department of Internal Medicine, Jiangsu Cancer Hospital, Jiangsu Institute of Cancer Research, The Affiliated Cancer Hospital of Nanjing Medical University, 42, Baiziting, Xuanwu District, Nanjing, Jiangsu, 210009, People’s Republic of China, Tel/Fax +86-025-83284611, Email drlihongyan12@163.comPurpose: Diffuse large B-cell lymphoma (DLBCL) is a prevalent malignant condition with a dismal prognosis. LncRNA PGM5 antisense RNA 1 (PGM5‐AS1) appears to be intricately involved in the progression of DLBCL, yet the modulatory mechanism remains unclear. The purpose of this study was to explore the expression of lncRNA PGM5-AS1 in DLBCL and its effect on the disease progression of DLBCL, as well as to explore its mechanisms.Patients and Methods: A total of 35 patients were included in the study. The expression levels of PGM5-AS1 and miR-503-5p in DLBCL tumor tissues and cell lines were detected by RT-qPCR. Cell proliferation was assessed using CCK8. Apoptosis rate was determined by flow cytometry. Cell invasion was examined by transwell assays. The specific interaction between PGM5-AS1 and miR-503-5p was verified through dual luciferase reporter gene assays. The immune related factors were detected by ELASA kits. The CD8+ T cells cytotoxicity was evaluated by LDH cytotoxicity kit.Results: In DLBCL tumor tissues and cells, upregulated PGM5-AS1 expression, downregulated miR-503-5p expression, and elevated PD-L1 expression were observed. PGM5-AS1 functioned as a regulator in controlling DLBCL cell proliferation, apoptosis, and invasion by downregulating miR-503-5p expression. When CD8+ T cells were co-cultured with cells transfected with si-PGM5-AS1, the secretion of immunoregulatory factors increased, and the cytotoxicity of CD8+ T cells increased. These effects were mitigated by miR-503-5p inhibitors.Conclusion: PGM5-AS1 accelerated DLBCL development and facilitated tumor immune escape through the miR-503-5p. Our discoveries offered an insight into lncRNA PGM5-AS1 serving as a prospective therapeutic target for DLBCL.Keywords: PGM5-AS1, miR-503-5p, DLBCL, immune escape