New roles of tumor-derived exosomes in tumor microenvironment

Throughout tumorigenesis, the co-evolution of tumor cells and their surrounding microenvironment leads to the development of malignant phenotypes. Cellular communication within the tumor microenvironment(TME) plays a critical role in influencing various aspects of tumor progression, including invasion and metastasis. The release of exosomes, a type of extracellular vesicle, by most cell types in the body, is an essential mediator of intercellular communication. A growing body of research indicates that tumor-derived exosomes(TDEs) significantly expedite tumor progression through multiple mechanisms, inducing epithelial-mesenchymal transition and macrophage polarization, enhancing angiogenesis, and aiding in the immune evasion of tumor cells. Herein, we describe the formation and characteristics of the TME, and summarize the contents of TDEs and their diverse functions in modulating tumor development. Furthermore, we explore potential applications of TDEs in tumor diagnosis and treatment.

Transplantation of fibrin-thrombin encapsulated human induced neural stem cells promotes functional recovery of spinal cord injury rats through modulation of the microenvironment

Recent studies have mostly focused on engraftment of cells at the lesioned spinal cord,with the expectation that differentiated neurons facilitate recovery.Only a few studies have attempted to use transplanted cells and/or biomaterials as major modulators of the spinal cord injury microenvironment.Here,we aimed to investigate the role of microenvironment modulation by cell graft on functional recovery after spinal cord injury.Induced neural stem cells reprogrammed from human peripheral blood mononuclear cells,and/or thrombin plus fibrinogen,were transplanted into the lesion site of an immunosuppressed rat spinal cord injury model.Basso,Beattie and Bresnahan score,electrophysiological function,and immunofluorescence/histological analyses showed that transplantation facilitates motor and electrophysiological function,reduces lesion volume,and promotes axonal neurofilament expression at the lesion core.Examination of the graft and niche components revealed that although the graft only survived for a relatively short period(up to 15 days),it still had a crucial impact on the microenvironment.Altogether,induced neural stem cells and human fibrin reduced the number of infiltrated immune cells,biased microglia towards a regenerative M2 phenotype,and changed the cytokine expression profile at the lesion site.Graft-induced changes of the microenvironment during the acute and subacute stages might have disrupted the inflammatory cascade chain reactions,which may have exerted a long-term impact on the functional recovery of spinal cord injury rats.

Spatial transcriptomics reveals that metabolic characteristics define the tumor immunosuppression microenvironment via iCAF transformation in oral squamous cell carcinoma

Tumor progression is closely related to tumor tissue metabolism and reshaping of the microenvironment. Oral squamous cell carcinoma (OSCC), a representative hypoxic tumor, has a heterogeneous internal metabolic environment. To clarify the relationship between different metabolic regions and the tumor immune microenvironment (TME) in OSCC, Single cell (SC) and spatial transcriptomics (ST) sequencing of OSCC tissues were performed. The proportion of TME in the ST data was obtained through SPOTlight deconvolution using SC and GSE103322 data. The metabolic activity of each spot was calculated using scMetabolism,and k-means clustering was used to classify all spots into hyper-, normal-, or hypometabolic regions. CD4T cell infiltration and TGF-βexpression is higher in the hypermetabolic regions than in the others. Through CellPhoneDB and NicheNet cell-cell communication analysis, it was found that in the hypermetabolic region, fibroblasts can utilize the lactate produced by glycolysis of epithelial cells to transform into inflammatory cancer-associated fibroblasts (iCAFs), and the increased expression of HIF1A in iCAFs promotes the transcriptional expression of CXCL12. The secretion of CXCL12 recruits regulatory T cells (Tregs), leading to Treg infiltration and increased TGF-β secretion in the microenvironment and promotes the formation of a tumor immunosuppressive microenvironment. This study delineates the coordinate work axis of epithelial cells-iCAFs-Tregs in OSCC using SC, ST and TCGA bulk data, and highlights potential targets for therapy.

Estimation of cancer cell migration in biomimetic random/oriented collagen fiber microenvironments

Increasing data indicate that cancer cell migration is regulated by extracellular matrixes and their surrounding biochemical microenvironment,playing a crucial role in pathological processes such as tumor invasion and metastasis.However,conventional two-dimensional cell culture and animal models have limitations in studying the influence of tumor microenvironment on cancer cell migration.Fortunately,the further development of microfluidic technology has provided solutions for the study of such questions.We utilize microfluidic chip to build a random collagen fiber microenvironment(RFM)model and an oriented collagen fiber microenvironment(OFM)model that resemble early stage and late stage breast cancer microenvironments,respectively.By combining cell culture,biochemical concentration gradient construction,and microscopic imaging techniques,we investigate the impact of different collagen fiber biochemical microenvironments on the migration of breast cancer MDA-MB-231-RFP cells.The results show that MDA-MB-231-RFP cells migrate further in the OFM model compared to the RFM model,with significant differences observed.Furthermore,we establish concentration gradients of the anticancer drug paclitaxel in both the RFM and OFM models and find that paclitaxel significantly inhibits the migration of MDA-MB-231-RFP cells in the RFM model,with stronger inhibition on the high concentration side compared to the low concentration side.However,the inhibitory effect of paclitaxel on the migration of MDA-MB-231-RFP cells in the OFM model is weak.These findings suggest that the oriented collagen fiber microenvironment resembling the late-stage tumor microenvironment is more favorable for cancer cell migration and that the effectiveness of anticancer drugs is diminished.The RFM and OFM models constructed in this study not only provide a platform for studying the mechanism of cancer development,but also serve as a tool for the initial measurement of drug screening.

Prognositic value of anoikis and tumor immune microenvironment-related gene in the treatment of osteosarcoma

Objective:Osteosarcoma is a highly aggressive primary malignant bone tumor commonly seen in children and adolescents,with a poor prognosis.Anchorage-dependent cell death(anoikis)has been proven to be indispensable in tumor metastasis,regulating the migration and adhesion of tumor cells at the primary site.However,as a type of programmed cell death,anoikis is rarely studied in osteosarcoma,especially in the tumor immune microenvironment.This study aims to clarify prognostic value of anoikis and tumor immune microenvironment-related gene in the treatment of osteosarcoma.Methods:Anoikis-related genes(ANRGs)were obtained from GeneCards.Clinical information and ANRGs expression profiles of osteosarcoma patients were sourced from the therapeutically applicable research to generate effective therapies and Gene Expression Omnibus(GEO)databases.ANRGs highly associated with tumor immune microenvironment were identified by the estimate package and the weighted gene coexpression network analysis(WGCNA)algorithm.Machine learning algorithms were performed to construct long-term survival predictive strategy,each sample was divided into high-risk and low-risk subgroups,which was further verified in the GEO cohort.Finally,based on single-cell RNA-seq from the GEO database,analysis was done on the function of signature genes in the osteosarcoma tumor microenvironment.Results:A total of 51 hub ANRGs closely associated with the tumor microenvironment were identified,from which 3 genes(MERTK,BNIP3,S100A8)were selected to construct the prognostic model.Significant differences in immune cell activation and immune-related signaling pathways were observed between the high-risk and low-risk groups based on tumor microenvironment analysis(all P<0.05).Additionally,characteristic genes within the osteosarcoma microenvironment were identified in regulation of intercellular crosstalk through the GAS6-MERTK signaling pathway.Conclusion:The prognostic model based on ANRGs and tumor microenvironment demonstrate good predictive power and provide more personalized treatment options for patients with osteosarcoma.

Hypoxic tumor microenvironment:Destroyer of natural killer cell function

In recent years, immunotherapy has made remarkable progress in treating certain tumors and hematological malignancies. However, the efficacy of natural killer(NK) cells, which are an important subset of innate lymphocytes used in anticancer immunotherapy, remains limited. Hypoxia, a critical characteristic of the tumor microenvironment(TME), is involved in tumor development and resistance to radiotherapy, chemotherapy, and immunotherapy. Moreover, hypoxia contributes to the impairment of NK cell function and may be a significant factor that limits their therapeutic effects. Targeted hypoxia therapy has emerged as a promising research area for enhancing the efficacy of NK cell therapy. Therefore, understanding how the hypoxic TME influences NK cell function is crucial for improving antitumor treatment outcomes.

Microenvironmental effects on growth response of Pinus massoniana to climate at its northern boundary in the Tongbai Mountains,Central China

The Tongbai Mountains is an ecologically sensi-tive region and the northern boundary of Pinus massoniana Lamb.To analyze the effect of different microenvironments on tree growth response to climate factors,we developed standard chronologies for earlywood width(EWW),late-wood width(LWW),and total ring width(TRW)of P.massoniana at two sampling sites on slopes with different orientations,then analyzed characteristics of the chronolo-gies and their correlations with climate variables from five stations in the region and with a regional normalized differ-ence vegetation index(NDVI).Statistical results showed that the TRW/EWW/LWW chronology consistency and charac-teristics(mean sensitivity,signal to noise ratio,expressed population signal)for trees growing on the southeastern slope were much higher than for trees on the northeastern slope.Correlations indicated that temperature in current March and August has a significant positive effect on TRW/EWW/LWW formation,and the effect on the northeastern slope was weaker than on the southeastern slope.Compared to temperature,precipitation has more complicated effects on tree growth,but the effect on the northeastern slope was also generally weaker than on the southeastern slope.Step-wise linear regression analyses showed that temperature in August was the main limiting factor at the two sampling sites.Similarly,the response of tree growth on the southeast-ern slope as determined by the NDVI is better than on the northeastern slope,and the TRW/EWW/LWW chronologies for the southeastern slope explained over 50%of the total NDVI variances in June.Overall,the results indicate that the difference in the climate response of P.massoniana at two sampling sites is clearly caused by differences in the microenvironment,and such differences should be properly considered in future studies of forest dynamics and climate reconstructions.

DNA Damage-driven Inflammatory Cytokines:Reprogramming of Tumor Immune Microenvironment and Application of Oncotherapy

DNA damage occurs across tumorigenesis and tumor development.Tumor intrinsic DNA damage can not only increase the risk of mutations responsible for tumor generation but also initiate a cellular stress response to orchestrate the tumor immune microenvironment(TIME)and dominate tumor progression.Accumulating evidence documents that multiple signaling pathways,including cyclic GMP-AMP synthase-stimulator of interferon genes(cGAS-STING)and ataxia telangiectasia-mutated protein/ataxia telangiectasia and Rad3-related protein(ATM/ATR),are activated downstream of DNA damage and they are associated with the secretion of diverse cytokines.These cytokines possess multifaced functions in the anti-tumor immune response.Thus,it is necessary to deeply interpret the complex TIME reshaped by damaged DNA and tumor-derived cytokines,critical for the development of effective tumor therapies.This manuscript comprehensively reviews the relationship between the DNA damage response and related cytokines in tumors and depicts the dual immunoregulatory roles of these cytokines.We also summarize clinical trials targeting signaling pathways and cytokines associated with DNA damage and provide future perspectives on emerging technologies.

The lactylation index predicts the immune microenvironment and prognosis of pan-cancer patients

Background:Protein lactylation is a new way for the“metabolic waste”lactic acid to perform novel functions.Nevertheless,our understanding of the contribution of protein lactylation to both tumor progression and therapeutic interventions remains imited.The construction of a scoring system for lactylation to predict the prognosis of pancancer patients and to evaluate the tumor immune microenvironment(TIME)would improve our understanding of the clinical significance of lactylation.Methods:Consensus clustering analysis of lactylation-related genes was used to cluster 177 pancreatic adenocarcinoma(PAAD)patients.Subsequently,a scoring system was developed using the least absolute shrinkage and selection operator(LASSO)regression.Internal validation and external validation were both conducted to assess and confirm the predictive accuracy of the scoring system.Finally,leucine rich repeat containing 1(LRRC1),a newly discovered lactylation-related gene,was analyzed in PAAD in vitro.Results:Utilizing the profiles of 332 lactylation-related genes,a total of 177 patients with PAAD were segregated into two distinct groups.LacCluster^(high) patients had a poorer prognosis than LacCluster^(low) patients.Through the differential analysis between the LacCluster^(high) and LacCluster^(low) groups,we identified additional genes associated with lactylation.These genes were then integrated to construct the LacCluster-enhanced system,which enabled more accurate prognosis prediction for patients with PAAD.Then,a lactylation index containing three genes(LacI-3)was constructed using LASSO regression.This was done to enhance the usability of the LacCluster-enhanced system in the clinic.Compared to those in the LacI-3^(high) subgroup,patients in the LacI-3^(low) subgroup exhibited increased expression of immune checkpoint-related genes,more immune cell infiltration,lower tumor mutation burdens,and better prognoses,indicating a“hot tumor”phenotype.Moreover,knocking down the expression of LRRC1,the hub gene in the LacI-3 scoring system,inhibited PAAD cell invasion,migration,and proliferation in vitro.Ultimately,the significance of LacI-3 across cancers was confirmed.Conclusion:Our findings strongly imply that protein lactylation may represent a new approach to diagnosing and treating malignant tumors.

Causal genetic regulation of DNA replication on immune microenvironment in colorectal tumorigenesis: Evidenced by an integrated approach of trans-omics and GWAS

The interplay between DNA replication stress and immune microenvironment alterations is known to play a crucial role in colorectal tumorigenesis,but a comprehensive understanding of their association with and relevant biomarkers involved in colorectal tumorigenesis is lacking.To address this gap,we conducted a study aiming to investigate this association and identify relevant biomarkers.We analyzed transcriptomic and proteomic profiles of 904 colorectal tumor tissues and 342 normal tissues to examine pathway enrichment,biological activity,and the immune microenvironment.Additionally,we evaluated genetic effects of single variants and genes on colorectal cancer susceptibility using data from genome-wide association studies(GWASs)involving both East Asian(7062 cases and 195745 controls)and European(24476 cases and 23073 controls)populations.We employed mediation analysis to infer the causal pathway,and applied multiplex immunofluorescence to visualize colocalized biomarkers in colorectal tumors and immune cells.Our findings revealed that both DNA replication activity and the flap structure-specific endonuclease 1(FEN1)gene were significantly enriched in colorectal tumor tissues,compared with normal tissues.Moreover,a genetic variant rs4246215 G>T in FEN1 was associated with a decreased risk of colorectal cancer(odds ratio=0.94,95%confidence interval:0.90–0.97,P_(meta)=4.70×10^(-9)).Importantly,we identified basophils and eosinophils that both exhibited a significantly decreased infiltration in colorectal tumors,and were regulated by rs4246215 through causal pathways involving both FEN1 and DNA replication.In conclusion,this trans-omics incorporating GWAS data provides insights into a plausible pathway connecting DNA replication and immunity,expanding biological knowledge of colorectal tumorigenesis and therapeutic targets.

Mechanisms of tumor immunosuppressive microenvironment formation in esophageal cancer

As a highly invasive malignancy,esophageal cancer(EC)is a global health issue,and was the eighth most prevalent cancer and the sixth leading cause of cancerrelated death worldwide in 2020.Due to its highly immunogenic nature,emerging immunotherapy approaches,such as immune checkpoint blockade,have demonstrated promising efficacy in treating EC;however,certain limitations and challenges still exist.In addition,tumors may exhibit primary or acquired resistance to immunotherapy in the tumor immune microenvironment(TIME);thus,understanding the TIME is urgent and crucial,especially given the importance of an immunosuppressive microenvironment in tumor progression.The aim of this review was to better elucidate the mechanisms of the suppressive TIME,including cell infiltration,immune cell subsets,cytokines and signaling pathways in the tumor microenvironment of EC patients,as well as the downregulated expression of major histocompatibility complex molecules in tumor cells,to obtain a better understanding of the differences in EC patient responses to immunotherapeutic strategies and accurately predict the efficacy of immunotherapies.Therefore,personalized treatments could be developed to maximize the advantages of immunotherapy.

Glycogen metabolism-mediated intercellular communication in the tumor microenvironment influences liver cancer prognosis

Glycogen metabolism plays a key role in the development of hepatoellular carcinoma(HCC),but the function of glycogen metabolism genes in the tumor microenvironment(TME)is still to be elucidated.Single cell RNA-seq data were obtained from ten HCC tumor samples totaling 64,545 cells and 65 glycogen metabolism genes were analyzed bya nonnegative matrix factorization(NMF).The prognosis and immune response of new glycogen TME cell dusters were predicted by using HCC and immunotherapy cohorts from public databases.HOC single cell analysis was divided into fibroblasts,NT T cells,macrophages,endothelial clls,and B cells,which were separately divided into new cell clusters by glycogen metabolism gene annotation.Pseudo temporal trajectory analysis demonstrated the temporal differentiation trajectory of different glycogen subtype cell dusters.Cellular communication analysis revealed extensive interactions between endothelial cells with glycogen metabolizing TME cell.related subtypes and diferent glycogen subtype cell clusters.SCENIC analysis of transcription factors upstream of TME cell clusters with different glycogen metabolism.In addition,TME cell dusters of glycogen metabolism were found to be enriched in expression in CAF subtypes,CD8 depleted,M1,and M2 types.Bulk seq analysis showed the prognostic signifcance of glycogen metabolism.mediated TME cell dusters in HCC,while a significant immune response was found in the immunotherapy cohort in patients treated with immune checkpoint blockade(ICB),especially for CAFs,T cells,and macrophages In summary,our study reveals for the first time that glycogen metabolism mediates intercellular communication in the hepatocellular carcinoma microenvironment while elucidating the anti-tumor mechanisms and immune prognostic responses of different subtypes of cell dusters.

Prognostic and predictive role of immune microenvironment in colorectal cancer

Colorectal cancer(CRC)represents a molecularly heterogeneous disease and one of the most frequent causes of cancer-related death worldwide.The traditional classification of CRC is based on pathomorphological and molecular character-istics of tumor cells(mucinous,ring-cell carcinomas,etc.),analysis of mechanisms of carcinogenesis involved(chromosomal instability,microsatellite instability,CpG island methylator phenotype)and mutational statuses of commonly altered genes(KRAS,NRAS,BRAF,APC,etc.),as well as expression signatures(CMS 1-4).It is also suggested that the tumor microenvironment is a key player in tumor progression and metastasis in CRC.According to the latest data,the immune microenvironment can also be predictive of the response to immune checkpoint inhibitors.In this review,we highlight how the immune environment influences CRC prognosis and sensitivity to systemic therapy.

Action of circulating and infiltrating B cells in the immune microenvironment of colorectal cancer by single-cell sequencing analysis

BACKGROUND The complexity of the immune microenvironment has an impact on the treatment of colorectal cancer(CRC),one of the most prevalent malignancies worldwide.In this study,multi-omics and single-cell sequencing techniques were used to investigate the mechanism of action of circulating and infiltrating B cells in CRC.By revealing the heterogeneity and functional differences of B cells in cancer immunity,we aim to deepen our understanding of immune regulation and provide a scientific basis for the development of more effective cancer treatment strategies.AIM To explore the role of circulating and infiltrating B cell subsets in the immune microenvironment of CRC,explore the potential driving mechanism of B cell development,analyze the interaction between B cells and other immune cells in the immune microenvironment and the functions of communication molecules,and search for possible regulatory pathways to promote the anti-tumor effects of B cells.METHODS A total of 69 paracancer(normal),tumor and peripheral blood samples were collected from 23 patients with CRC from The Cancer Genome Atlas database(https://portal.gdc.cancer.gov/).After the immune cells were sorted by multicolor flow cytometry,the single cell transcriptome and B cell receptor group library were sequenced using the 10X Genomics platform,and the data were analyzed using bioinformatics tools such as Seurat.The differences in the number and function of B cell infiltration between tumor and normal tissue,the interaction between B cell subsets and T cells and myeloid cell subsets,and the transcription factor regulatory network of B cell subsets were explored and analyzed.RESULTS Compared with normal tissue,the infiltrating number of CD20+B cell subsets in tumor tissue increased significantly.Among them,germinal center B cells(GCB)played the most prominent role,with positive clone expansion and heavy chain mutation level increasing,and the trend of differentiation into memory B cells increased.However,the number of plasma cells in the tumor microenvironment decreased significantly,and the plasma cells secreting IgA antibodies decreased most obviously.In addition,compared with the immune microenvironment of normal tissues,GCB cells in tumor tissues became more closely connected with other immune cells such as T cells,and communication molecules that positively regulate immune function were significantly enriched.CONCLUSION The role of GCB in CRC tumor microenvironment is greatly enhanced,and its affinity to tumor antigen is enhanced by its significantly increased heavy chain mutation level.Meanwhile,GCB has enhanced its association with immune cells in the microenvironment,which plays a positive anti-tumor effect.

Multifaceted roles of lymphatic and blood endothelial cells in the tumor microenvironment of hepatocellular carcinoma:A comprehensive review

The tumor microenvironment is a complex network of cells,extracellular matrix,and signaling molecules that plays a critical role in tumor progression and metastasis.Lymphatic and blood vessels are major routes for solid tumor metastasis and essential parts of tumor drainage conduits.However,recent studies have shown that lymphatic endothelial cells(LECs)and blood endothelial cells(BECs)also play multifaceted roles in the tumor microenvironment beyond their structural functions,particularly in hepatocellular carcinoma(HCC).This comprehensive review summarizes the diverse roles played by LECs and BECs in HCC,including their involvement in angiogenesis,immune modulation,lymphangiogenesis,and metastasis.By providing a detailed account of the complex interplay between LECs,BECs,and tumor cells,this review aims to shed light on future research directions regarding the immune regulatory function of LECs and potential therapeutic targets for HCC.

Hepatocellular carcinoma immune microenvironment and check point inhibitors-current status

Hepatocellular carcinoma(HCC)is the most common primary tumor of the liver and has a high mortality rate.The Barcelona Clinic Liver Cancer staging system in addition to tumor staging also links the modality of treatment available to a particular stage.The recent description of the tumor microenvironment(TME)in HCC has provided a new concept of immunogenicity within the HCC.Virusrelated HCC has been shown to be more immunogenic with higher expression of cytotoxic T lymphocytes and decreased elements for immunosuppression such as regulatory T cells.This immunogenic milieu provides a better response to immunotherapy especially immune checkpoint inhibitors(ICIs).In addition,the recent data on combining locoregional therapies and other strategies may convert the less immunogenic state of the TME towards higher immunogenicity.Therefore,data are emerging on the use of combinations of locoregional therapy and ICIs in unresectable or advanced HCC and has shown better survival outcomes in this difficult population.

Identification of immune cell-related prognostic genes characterized by a distinct microenvironment in hepatocellular carcinoma

BACKGROUND The development and progression of hepatocellular carcinoma(HCC)have been reported to be associated with immune-related genes and the tumor microenvir-onment.Nevertheless,there are not enough prognostic biomarkers and models available for clinical use.Based on seven prognostic genes,this study calculated overall survival in patients with HCC using a prognostic survival model and revealed the immune status of the tumor microenvironment(TME).AIM To develop a novel immune cell-related prognostic model of HCC and depict the basic profile of the immune response in HCC.METHODS We obtained clinical information and gene expression data of HCC from The Cancer Genome Atlas(TCGA)and International Cancer Genome Consortium(ICGC)datasets.TCGA and ICGC datasets were used for screening prognostic genes along with developing and validating a seven-gene prognostic survival model by weighted gene coexpression network analysis and least absolute shrinkage and selection operator regression with Cox regression.The relative analysis of tumor mutation burden(TMB),TME cell infiltration,immune check-points,immune therapy,and functional pathways was also performed based on prognostic genes.RESULTS Seven prognostic genes were identified for signature construction.Survival receiver operating characteristic curve analysis showed the good performance of survival prediction.TMB could be regarded as an independent factor in HCC survival prediction.There was a significant difference in stromal score,immune score,and estimate score between the high-risk and low-risk groups stratified based on the risk score derived from the seven-gene prognostic model.Several immune checkpoints,including VTCN1 and TNFSF9,were found to be associated with the seven prognostic genes and risk score.Different combinations of checkpoint blockade targeting inhibitory CTLA4 and PD1 receptors and potential chemotherapy drugs hold great promise for specific HCC therapies.Potential pathways,such as cell cycle regulation and metabolism of some amino acids,were also identified and analyzed.CONCLUSION The novel seven-gene(CYTH3,ENG,HTRA3,PDZD4,SAMD14,PGF,and PLN)prognostic model showed high predictive efficiency.The TMB analysis based on the seven genes could depict the basic profile of the immune response in HCC,which might be worthy of clinical application.

N6-methyladenosine methylation regulates the tumor microenvironment of Epstein-Barr virus-associated gastric cancer

BACKGROUND N6-methyladenosine(m6A)methylation modification exists in Epstein-Barr virus(EBV)primary infection,latency,and lytic reactivation.It also modifies EBV latent genes and lytic genes.EBV-associated gastric cancer(EBVaGC)is a distinctive molecular subtype of GC.We hypothesized EBV and m6A methylation regulators interact with each other in EBVaGC to differentiate it from other types of GC.AIM To investigate the mechanisms of m6A methylation regulators in EBVaGC to determine the differentiating factors from other types of GC.METHODS First,The Cancer Gene Atlas and Gene Expression Omnibus databases were used to analyze the expression pattern of m6A methylation regulators between EBVaGC and EBV-negative GC(EBVnGC).Second,we identified Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)functional enrichment of m6A-related differentially expressed genes.We quantified the relative abundance of immune cells and inflammatory factors in the tumor microenvironment(TME).Finally,cell counting kit-8 cell proliferation test,transwell test,and flow cytometry were used to verify the effect of insulin-like growth factor binding protein 1(IGFBP1)in EBVaGC cell lines.RESULTS m6A methylation regulators were involved in the occurrence and development of EBVaGC.Compared with EBVnGC,the expression levels of m6A methylation regulators Wilms tumor 1-associated protein,RNA binding motif protein 15B,CBL proto-oncogene like 1,leucine rich pentatricopeptide repeat containing,heterogeneous nuclear ribonucleoprotein A2B1,IGFBP1,and insulin-like growth factor 2 binding protein 1 were significantly downregulated in EBVaGC(P<0.05).The overall survival rate of EBVaGC patients with a lower expression level of IGFBP1 was significantly higher(P=0.046).GO and KEGG functional enrichment analyses showed that the immunity pathways were significantly activated and rich in immune cell infiltration in EBVaGC.Compared with EBVnGC,the infiltration of activated CD4+T cells,activated CD8+T cells,monocytes,activated dendritic cells,and plasmacytoid dendritic cells were significantly upregulated in EBVaGC(P<0.001).In EBVaGC,the expression level of proinflammatory factors interleukin(IL)-17,IL-21,and interferon-γ and immunosuppressive factor IL-10 were significantly increased(P<0.05).In vitro experiments demonstrated that the expression level of IGFBP1 was significantly lower in an EBVaGC cell line(SNU719)than in an EBVnGC cell line(AGS)(P<0.05).IGFBP1 overexpression significantly attenuated proliferation and migration and promoted the apoptosis levels in SNU719.Interfering IGFBP1 significantly promoted proliferation and migration and attenuated the apoptosis levels in AGS.CONCLUSION m6A regulators could remodel the TME of EBVaGC,which is classified as an immune-inflamed phenotype and referred to as a“hot”tumor.Among these regulators,we demonstrated that IGFBP1 affected proliferation,migration,and apoptosis.

Immune signature of small bowel adenocarcinoma and the role of tumor microenvironment

In this editorial we comment on the article published“Clinical significance of programmed cell death-ligand expression in small bowel adenocarcinoma is determined by the tumor microenvironment”.Small bowel adenocarcinoma(SBA)is a rare gastrointestinal neoplasm and despite the small intestine's significant surface area,SBA accounts for less than 3%of such tumors.Early detection is challenging and the reason arises from its asymptomatic nature,often leading to late-stage discovery and poor prognosis.Treatment involves platinum-based chemotherapy with a 5-fluorouracil combination,but the lack of effective chemotherapy contributes to a generally poor prognosis.SBAs are linked to genetic disorders and risk factors,including chronic inflammatory conditions.The unique characteristics of the small bowel,such as rapid cell renewal and an active immune system,contributes to the rarity of these tumors as well as the high intratumoral infiltration of immune cells is associated with a favorable prognosis.Programmed cell death-ligand 1(PD-L1)expression varies across different cancers,with potential discrepancies in its prognostic value.Microsatellite instability(MSI)in SBA is associated with a high tumor mutational burden,affecting the prognosis and response to immunotherapy.The presence of PD-L1 and programmed cell death 1,along with tumor-infiltrating lymphocytes,plays a crucial role in the complex microenvironment of SBA and contributes to a more favorable prognosis,especially in the context of high MSI tumors.Stromal tumor-infiltrating lymphocytes are identified as independent prognostic indicators and the association between MSI status and a favorable prognosis,emphasizes the importance of evaluating the immune status of tumors for treatment decisions.

Nanomaterials for refining tumor microenvironment and enhancing therapy in head and neck squamous cell carcinoma: a review

Head and neck squamous cell carcinoma (HNSCC) is a prevalent and lethal solid tumor with a high mortality rate. Conventional cancertreatments, including surgery, radiotherapy, and chemotherapy, primarily target cancer cell eradication. However, uncontrolled proliferation and metabolic activities of these cells result in abnormalities in nutrient levels, hypoxia, and immunosuppression within the tumor microenvironment (TME). These factors constrain the efficacy of traditional treatments by promoting drug resistance, recurrence, and metastasis. Nanomaterials (NMs), such as nanozymes, can exhibit enzymatic activity similar to that of natural enzymes and offer a promising avenuefor the direct modification of the TME through catalytic oxidation-reduction processes. Moreover, they can serve as sensitizers or drug deliverycarriers, enhancing the efficacy of traditional treatment methods. Recently, NMs have garnered significant attention from oncologists. Thisreview begins with an overview of the composition and unique characteristics of the TME. Subsequently, we comprehensively exploredthe application of NMs in the treatment of HNSCC. Finally, we discuss the potential prospects and challenges associated with usingNMs in biomedical research.