Possible mechanisms associated with immune escape and apoptosis on anti-hepatocellular carcinoma effect of Mu Ji Fang granules

BACKGROUND Hepatocellular carcinoma(HCC)is one of the most common digestive system cancers with high mortality rates worldwide.The main ingredients in Mu Ji Fang Granules(MJF)are alkaloids,flavonoids,and polysaccharides.MJF has been used in the clinical treatment of hepatitis,cirrhosis and HCC for more than 30 years.Few previous studies have focused on the mechanism of MJF on tumor immunology in the treatment of HCC.AIM To explore the mechanism of action of MJF on tumor immunology in the treatment of HCC.METHODS The absorbable ingredients of MJF were identified using Molecule Network related to High Performance Liquid Chromatography-Electron Spray Ionization-Time of Flight-Mass Spectrometry,and hub potential anti-HCC targets were screened using network pharmacology and pathway enrichment analysis.Forty male mice were randomly divided into the Blank,Model,and MJF groups(1.8,5.4,and 10.8 g/kg/d)following 7 d of oral administration.Average body weight gain,spleen and thymus indices were calculated,tumor tissues were stained with hematoxylin and eosin,and Interferon gamma(IFN-γ),Tumor necrosis factorα(TNF-α),Interleukin-2,aspartate aminotransferase,alanine aminotransferase,alpha-fetoprotein(AFP),Fas,and FasL were measured by Enzyme-linked Immunosorbent Assay.Relevant mRNA expression of Bax and Bcl2 was evaluated by Real Time Quantitative PCR(RTqPCR)and protein expression of Transforming growth factorβ1(TGF-β1)and Mothers against decapentaplegic homolog(SMAD)4 was assessed by Western blotting.The HepG2 cell line was treated with 10 mg/mL,20 mg/mL,30 mg/mL,40 mg/mL of MJF,and another 3 groups were treated with TGF-β1 inhibitor(LY364947)and different doses of MJF.Relevant mRNA expression of TNF-α,IFN-γ,Bax and Bcl2 was evaluated by RT-qPCR and protein expression of TGF-β1,SMAD2,p-SMAD2,SMAD4,and SMAD7 was assessed by Western blotting.RESULTS It was shown that MJF improved body weight gain and tumor inhibition rate in H22 tumorbearing mice,protected immune organs and liver function,reduced the HCC indicator AFP,affected immunity and apoptosis,and up-regulated the TGF-β1/SMAD signaling pathway,by increasing the relative expression of TGF-β1,SMAD2,p-SMAD2 and SMAD4 and decreasing SMAD7,reducing immune factors TNF-αand IFN-γ,decreasing apoptosis cytokines Fas,FasL and Bcl2/Bax,and inhibiting the effect of LY364947 in HepG2 cells.CONCLUSION MJF inhibits HCC by activating the TGF-β1/SMAD signaling pathway,and affecting immune and apoptotic cytokines,which may be due to MJF adjusting immune escape and apoptosis.

Initial Study on Immune Escape Mechanism of Mouse Acute Myelomonocytic Leukemic Cell Line WEHI-3

Objective： To investigate the expression of Fas, Fas ligand （FasL） and CD80 on the cell surface of mouse acute myelomonocytic leukemia cell line WEHI-3 and the function of FasL. Methods： The expression of Fas, FasL and CD80 was detected on WEHI-3 cell surface by flow cytometry. Simultaneously the function of FasL was determined by Thymidine （^3H-TdR） Incorporation. Results： The expression of CD80 and Fas on WEHI-3 cell surface was 5.06%±0.41% and 6.75%±2.31% （n=5） respectively, and the expression of FasL was up to 63.73%±5.23% （n=5）. The apoptotic rate of YAC-1 cells was 26%±4.5%, 35%±3.2% and 43%±2.7% （n=5） respectively when WEHI-3 （effector cell, E） and Fas^＋ YAC-1 cells （target cell, T） were cultured in the ratio of 3：1, 10：1 and 30：1. Conclusion： WEHI-3 cells express high FasL, low Fas and CD80, and can induce apoptosis of Fas^＋ YAC-1 cells.

Aryl hydrocarbon receptor dynamics in esophageal squamous cell carcinoma:From immune modulation to therapeutic opportunities

Esophageal squamous cell carcinoma(ESCC)is a substantial global health burden.Immune escape mechanisms are important in ESCC progression,enabling cancer cells to escape the surveillance of the host immune system.One key player in this process is the Aryl Hydrocarbon Receptor(AhR),which influences multiple cellular processes,including proliferation,differentiation,metabolism,and immune regulation.Dysregulated AhR signaling participates in ESCC development by stimulating carcinogenesis,epithelial-mesenchymal transition,and immune escape.Targeting AhR signaling is a potential therapeutic approach for ESCC,with AhR ligands showing efficacy in preclinical studies.Additionally,modification of AhR ligands and combination therapies present new opportunities for therapeutic intervention.This review aims to address the knowledge gap related to the role of AhR signaling in ESCC pathogenesis and immune escape.

Single-cell RNA-seq reveals the immune escape and drug resistance mechanisms of mantle cell lymphoma

Objective:Mantle cell lymphoma(MCL)is a rare subtype of non-Hodgkin lymphoma(NHL)with high heterogeneity and a high recurrence rate.How heterogenous cell populations contribute to relapse remains to be elucidated.Methods:We performed single cell RNA sequencing(scRNA-seq)on approximately 4,000 bone marrow cells sampled from one patient with multidrug resistant MCL.We identified 10 subpopulations comprising 4 malignant B cell subtypes,3 T cell subtypes,2 dendritic cell subtypes and 1 natural killer(NK)cell subtype.Subsequently,we identified cell markers,including a series of genes associated with immune escape and drug resistance.In addition,we explored the roles of these genes in the mechanism of immune escape and drug resistance,and we verified the expression imbalance and clinical prognostic potential by using GEO datasets including 211 MCL samples.Results:The major immune escape mechanisms of MCL included anti-perforin activity,decreased immunogenicity and direct inhibition of apoptosis and cell killing,as mediated by type I and II B cells.The drug resistance mechanisms of different cell clusters included drug metabolism,DNA damage repair,apoptosis and survival promotion.Type III B cells closely communicate with other cells.The key genes involved in the resistance mechanisms showed dysregulated expression and may have significant clinical prognostic value.Conclusion:This study investigated potential immune escape and drug resistance mechanisms in MCL.The results may guide individualized treatment and promote the development of therapeutic drugs.

Action and mechanism of Fas and Fas ligand in immune escape of gallbladder carcinoma

AIM: To study the role of Fas and Fas ligand (FasL) in biological behaviors of gallbladder carcinoma, and their correlated action and mechanism in tumor escape.METHODS: Streptavidin-biotin-peroxidase immunohistochemistry technique was used to study the expression of Fas and FasL protein in 26 gallbladder carcinoma tissues,18 gallbladder adenoma tissues, 3 gallbladder dysplasia tissues and 20 chronic cholecystitis tissues. Apoptosis of the infiltrating lymphocytes in these tissues was studied by terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick-end labeling (TUNEL) method. Expression of both proteins and apoptosis of the tumor infiltrating lymphocytes in cancer tissues of primary foci was compared with clinicopathological features of gallbladder carcinoma.RESULTS: The positive rates of Fas were not significantly different among carcinoma, adenoma, dysplasia and chronic cholecystitis. The positive rate of FasL in carcinoma was significantly higher than that in chronic cholecystitis (x2 = 4.89, P＜0.05). The apoptotic index (AI) in carcinoma was significantly higher than that in adenoma (t'= 4.19, P＜0.01) and chronic cholecystitis (t'= 8.06, P＜0.01). The AI was significantly lower in well-differentiated carcinoma and Nevin Ⅰ-Ⅲ carcinoma than that in poorly-differentiated carcinoma (t'= 2.63, P＜0.05) and Nevin Ⅳ-Ⅴ carcinoma(t'= 3.33, P＜0.01). The confidence interval (CI) ofinfiltrating lymphocytes in adenoma, chronic cholecystitis, well-differentiated carcinoma and Nevin Ⅰ-Ⅲ carcinoma wasvery significantly lower than that in carcinoma (t' = 6.99,P＜0.01), adenoma (t' = 3.66, P＜0.01), poorly-differentiated carcinoma (t' = 5.31, P＜0.01) and Nevin Ⅳ-Ⅴ carcinoma(t' = 3.76, P＜0.01), respectively. The CI of apoptosis of infiltrating lymphocytes in well-differentiated carcinoma was significantly lower than that in poorly-differentiated carcinoma (t = 2.52, P＜0.05), and was not significantly lower in Nevin Ⅰ-Ⅲ carcinoma than in Nevin Ⅳ-Ⅴ carcinoma (t = 1.42, P＞0.05). Apoptosis of infiltrating lymphocytes was not discovered in adenoma and chronic cholecystitis. CONCLUSION: FasL expressed in gallbladder carcinoma cells permits tumor cells to escape from immune surveillance of organism by inducing apoptosis in infiltrating lymphocytes of carcinoma tissues. Up-regulation of FasL expression plays an important role in invasive depth, histological classification and metastasis of gallbladder carcinoma.

Costimulatory Molecule B7-H1 on the Immune Escape of Bladder Cancer and Its Clinical Significance

B7-H1, a recently described member of the B7 family of costimulatory molecules, is thought to be involved in tumor immune escape by inducing T-cell apoptosis. In order to investigate the relationship between B7-H1 and immune escape of bladder cancer, B7-H1 expression in 50 cases of bladder cancer was detected by using immunohistochemical method. Survival curves were con- structed using the Kaplan-Meier method and independent prognostic factors were evaluated using the Cox regression model. Our results showed that the positive rate of B7-H1 immunostaining in normal bladder tissue and bladder cancer was 0 and 72% respectively. The expression of B7-H1 was strongly associated with the pathological grade, clinical stage and recurrence （P〈0.05）. The survival rate was significantly lower in patients with B7-H1 positive group than in those with B7-H1 negative group and multi-variable analysis revealed that B7-H1 could be regarded as an independent factor in evaluating the prognosis of bladder cancer. It is concluded that the expression of B7-H1 is strongly associated with neoplastic progression and prognosis of bladder cancer. The manipulation of B7-H1 may become a beneficial target for immunotherapy in human bladder cancer.

Shuyu pills inhibit immune escape and enhance chemosensitization in hepatocellular carcinoma

BACKGROUND Hepatocellular carcinoma(HCC)is characterized by dysregulation of the immune microenvironment and the development of chemoresistance.Specifically,expression of the programmed cell death protein 1(PD-1)/programmed cell death 1 ligand 1(PD-L1)axis,an immune checkpoint,may lead to tumour immune escape,resulting in disease progression.The latest research shows that tumour immune escape may be caused by the upregulation of PD-L1 mediated by hypoxia-inducible factor-1 alpha(HIF-1α),and simultaneous inhibition of HIF-1αand PD-L1 has the potential to enhance the host’s antitumour immunity.Moreover,inhibition of the PD-1/PD-L1 axis may mitigate tumour chemoresistance.Shuyu pills(SYPs)contain immunity-enhancing and antitumour components,making them a potential HCC treatment.AIM To investigate the efficacy of SYPs for HCC treatment via simultaneous HIF-1α and PD-L1 inhibition and the mechanism involved.METHODS A subcutaneous xenograft tumour model was first established in BALB/c nude mice by the subcutaneous injection of 1×107 SMMC-7721 cells.Male mice(male,5 weeks old;n=24)were then randomly divided into the following four groups(n=6):Control(0.9%normal saline),SYP(200 mg/kg),SYP+cisplatin(DDP)(200 mg/kg+5 mg/kg DDP weekly via intraperitoneal injection),and DDP(5 mg/kg cisplatin weekly via intraperitoneal injection).The dose of saline or SYPs for the indicated mouse groups was 0.2 mL/d via intragastric administration.The tumour volumes and body weights of the mice were measured every 2 d.The mice were euthanized by cervical dislocation after 14 d of continuous treatment,and the xenograft tissues were excised and weighed.Western blot assays were used to measure the protein expression of HIF-1α,PD1,PD-L1,CD4+T cells,and CD8+T cells in HCC tumours from mice.Quantitative reverse transcription polymerase chain reaction was used for real-time quantitative detection of PD-1,PD-L1,and HIF-1α mRNA expression.An immunofluorescence assay was conducted to examine the expression of CD4+T cells and CD8+T cells.RESULTS Compared to mice in the control group,those in the SYP and SYP+DDP groups exhibited reduced tumour volumes and tumour weights.Moreover,the protein and mRNA expression levels of the oncogene HIF1α and that of the negative immunomodulatory factors PD-1 and PD-L1 were decreased in both the SYP and SYP+DDP groups,with the decrease effects being more prominent in the SYP+DDP group than in the SYP group(HIF-1α protein:Control vs SYP,P=0.0129;control vs SYP+DDP,P=0.0004;control vs DDP,P=0.0152,SYP+DDP vs DDP,P=0.0448;HIF-1αmRNA:control vs SYP,P=0.0009;control vs SYP+DDP,P<0.0001;control vs DDP,P=0.0003,SYP vs SYP+DDP,P=0.0192.PD-1 protein:Control vs SYP,P=0.0099;control vs SYP+DDP,P<0.0001,SPY vs SYP+DDP,P=0.0009;SYP+DDP vs DDP,P<0.0001;PD-1 mRNA:control vs SYP,P=0.0002;control vs SYP+DDP,P<0.0001;control vs DDP,P=0.0003,SPY vs SYP+DDP,P=0.0003;SYP+DDP vs DDP,P=0.0002.PD-L1 protein:control vs SYP,P<0.0001;control vs SYP+DDP,P<0.0001;control vs DDP,P<0.0001,SPY vs SYP+DDP,P=0.0040;SYP+DDP vs DDP,P=0.0010;PD-L1 mRNA:Control vs SYP,P<0.0001;control vs SYP+DDP,P<0.0001;control vs DDP,P<0.0001,SPY vs SYP+DDP,P<0.0001;SYP+DDP vs DDP,P=0.0014).Additionally,the quantitative and protein expression levels of CD4+T cells and CD8+T cells were simultaneously upregulated in the SYP+DDP group,whereas only the expression of CD4+T cells was upregulated in the SYP group.(CD4+T cell quantitative:Control vs SYP+DDP,P<0.0001,SYP vs SYP+DDP,P=0.0005;SYP+DDP vs DDP,P=0.0002.CD4+T cell protein:Control vs SYP,P=0.0033;Control vs SYP+DDP,P<0.0001;Control vs DDP,P=0.0021,SYP vs SYP+DDP,P=0.0004;SYP+DDP vs DDP,P=0.0006.Quantitative CD8+T cells:Control vs SYP+DDP,P=0.0013;SYP vs SYP+DDP,P=0.0347;SYP+DDP vs DDP,P=0.0043.CD8+T cell protein:Control vs SYP+DDP,P<0.0001;SYP vs SYP+DDP,P<0.0001;SYP+DDP vs DDP,P<0.0001).Finally,expression of HIF-1αwas positively correlated with that of PD-1/PD-L1 and negatively correlated with the expression of CD4+T cells and CD8+T cells.CONCLUSION SYPs inhibit immune escape and enhance chemosensitization in HCC via simultaneous inhibition of HIF-1α and PD-L1,thus inhibiting the growth of subcutaneous xenograft HCC tumours.

Role of cytokines in promoting immune escape of FasL-expressing human colon cancer cells

AIM: To investigate the potential role of cytokines in promoting Fas ligand (FasL)-expressing colon cancer cells. METHODS: Immunohistochemical SABC method was used to observe the expression of Fas receptor and ligand in SW620 colon cancer cell line and Jurkat T cells in order to provide the morphological evidence for the functions of Fas receptor and ligand. To examine the cytotoxicity of effector cells, CytoTox96 non-radioactive cytotoxicity assay was adopted to measure the lactate dehydrogenase-releasing value after SW620 cells were co-cultured with Jurkat T lymphocytes. RESULTS: The FasL of colon cancer SW620 cells was positive. The positive substances were distributed in the cell membrane and cytoplasm. The Fas receptor of colon cancer SW620 cells was negative. The Fas receptor and ligand of Jurkat T lymphocytes turned out to be positive. The positive substances were distributed in the cell membrane. After phytohemagglutinin (PHA)-stimulated Jurkat T lymphocytes were co-cultured with phorbol 12-myristate 13-acetate (PMA)-plus-ionomycin-stimulated (for 48 h) SW620 cells or tumor necrosis factor-alpha (TNF-α)-stimulated (for 48 h) SW620 cells or unstimulated SW620 cells for 4 h, the cytotoxicity of SW620 cells to PHA-stimulated Jurkat cells at effector-to-target ratios of 10:1, 5:1, 2.5:1, and 1.25:1 was 74.6%, 40.8%, 32.4%, and 10.9% (F= 8.19, P<0.05); or 54.9%, 35.3%, 22.0%, and 10.3% (F= 11.12, P<0.05); or 14.9%, 10.5%, 6.9%, and 5.8% (F = 3.45, P<0.05). After PHA-stimulated Jurkat T lymphocytes were co-cultured with unstimulated SW620 cells for 8 h, the cytotoxicity of SW620 cells to PHA-stimulated Jurkat cells at effector-to-target ratios of 5:1, 2.5:1, and 1.25:1 from the experiment was 83.9%, 74.1%, and 28.5% (F=137.04, P<0.05) respectively. Non-radioactive cytotoxicity assay showed that the apoptotic rate of Jurkat cells remarkably increased with the increase of planting concentration of SW620 cells and co-culture time after the SW620 cells were co-cultured with the Jurkat T lymphocytes. The cytotoxicity was significantly enhanced by PMA+ionomycin or TNF-α. CONCLUSION: The FasL expressed in human colon cancer cells may be regulated by endogenous factors in the microenvironment of the host and facilitate the escape of tumor cells from the host immune system.

Morphine-3-glucuronide upregulates PD-L1 expression via TLR4 and promotes the immune escape of non-small cell lung cancer

Objective:Patients with cancer pain are highly dependent on morphine analgesia,but studies have shown a negative correlation between morphine demand and patient outcomes.The long-term use of morphine may result in abnormally elevated serum morphine-3-glucuronide(M3G)levels.Hence,the effects of M3G on tumor progression are worth studying.Methods:The effects of M3G on PD-L1 expressions in human non-small cell lung cancer(NSCLC)cell lines were first evaluated.Activation of TLR4 downstream pathways after M3G treatment was then determined by Western blot.The effects of M3G on human cytotoxic T lymphocytes(CTL)cytotoxicity and INF-γrelease was also detected.Finally,the LLC murine lung adenocarcinoma cell line were used to establish a murine lung cancer model,and the effects of M3G on tumor growth and metastasis were determined.Results:M3G promoted the expressions of PD-L1 in the A549 and H1299 cell lines in a TLR4-dependent manner(P<0.05).M3G activated the PI3 K and the NFκB signaling pathways,and this effect was antagonized by a TLR4 pathway inhibitor.A PI3 K pathway inhibitor reversed the M3G-mediated PD-L1 upregulation.M3G inhibited the cytotoxicity of CTL on A549 cells and decreased the level of INF-γ.Repeated M3G intraperitoneal injections promoted LLC tumor growth and lung metastasis through the upregulation of tumor expressed PD-L1 and the reduction of CTL in the tumor microenvironment.Conclusions:M3G specifically activated TLR4 in NSCLC cells and upregulated PD-L1 expression through the PI3 K signaling pathway,thereby inhibiting CTL cytotoxicity and finally promoting tumor immune escape.

Role of immune escape in different digestive tumours

A counterbalance between immune cells and tumour cells is key to fighting tumours,and immune escape is an important mechanism for the survival of tumour cells in the body.Tumor cells and their cytokines impair the activity of T cells,NK cells,macrophages and other immune cells through various ways,and change the expression of their own surface antigens so as to avoid the clearance of the immune system.Changes in major histocompatibility complex molecules,high expression of programmed death-ligand 1,and the presence of immunosuppressive cells in the tumor microenvironment(TME)are main means by which tumors impair the function of immune cells.During the development of tumours of the digestive system,different mechanisms acting on tumour cells,the TME,and immune cells lead to immune escape and promote tumour progression.In this paper,the mechanisms of immune escape in tumour cells of the digestive system are reviewed to provide a theoretical basis for the immunotherapy of gastrointestinal tumours.

The interaction between end-metabolites and immune escape

Emerging data from metabolites-relating trails in cancers demonstrate that a common mechanism of resistance to many novel classes of immune therapeutics is the emergence of immune escape due to the reprogramming of cellular metabolism.Among them,current work about end-metabolites mostly focuses on the intersection between lactate acid,adenosine,reactive oxygen species(ROS),and tumour immune escape.In this article,we aim to review the evidence to date for the dynamic interplay between the three end-metabolites and tumour immune escape for potential approaches to overcome obstacles in the efficacy and durability of immune cancer therapies.We have organized known end-metabolites-associated immune escape mechanisms into three hallmarks:(1)decreased immunogenicity of cancer cells which constitutes defective antigen presentation and the attenuated expression of costimulatory molecules on tumour cells,(2)immunosuppressive microenvironment with aberrant angiogenesis inhibits the differentiation,maturation,and immune deviation of immune cells while drives the activation of immunosuppressive cells by immune-suppressive mediators(cytokines and other factors),(3)immune tolerance retained by inhibitory molecules and depletion of immune cells.

Advances in research on relationship between tumor immune escape and tumor microenvironment

Tumor immune escape is an important way for tumor cells to evade surveillance and attack by host immune system and promote tumor survival and proliferation.Immunotherapy for immune escape has made significant progress in recent years.Immunotherapy involves multiple factors and pathways,and is associated with changes in tumor cells themselves and tumor microenvironments,and the mechanisms are complex.At present,there are still many challenges in the clinical practice process.Starting from the tumor microenvironment,the article describes the role of various cells in the tumor microenvironment on tumor cell immune escape.

The DMRTA1-SOX2 positive feedback loop promotes progression and chemotherapy resistance of esophageal squamous cell carcinoma

Esophageal squamous cell carcinoma(ESCC)is among the most prevalent causes of cancer-related death in patients worldwide.Resistance to immunotherapy and chemotherapy results in worse survival outcomes in ESCC.It is urgent to explore the underlying molecular mechanism of immune evasion and chemoresistance in ESCC.Here,we conducted RNA-sequencing analysis in ten ESCC tissues from cisplatin-based neoadjuvant chemotherapy patients.We found that DMRTA1 was extremely upregulated in the non-pathologic complete response(non-pCR)group.The proliferation rate of esophageal squamous carcinoma cells was markedly decreased after knockdown of DMRTA1 expression,which could increase cisplatin sensitivity in ESCC.Additionally,suppression of DMRTA1 could decrease the immune escape of esophageal squamous carcinoma cells.Further mechanistic studies suggest that DMRTA1 can promote its expression by binding to the promoter of SOX2,which plays important roles in the progression and chemoresistance of ESCC in the form of positive feedback.Therefore,DMRTA1 could be a potential target to suppress immune escape and overcome chemoresistance in ESCC.

Recent progress in understanding mitokines as diagnostic and therapeutic targets in hepatocellular carcinoma

Hepatocellular carcinoma(HCC)is one of the most prevalent tumors worldwide and the leading contributor to cancer-related deaths.The progression and metastasis of HCC are closely associated with altered mitochondrial metabolism,including mitochondrial stress response.Mitokines,soluble proteins produced and secreted in response to mitochondrial stress,play an essential immunomodulatory role.Immunotherapy has emerged as a crucial treatment option for HCC.However,a positive response to therapy is typically dependent on the interaction of tumor cells with immune regulation within the tumor microenvironment.Therefore,exploring the specific immunomodulatory mechanisms of mitokines in HCC is essential for improving the efficacy of immunotherapy.This study provides a comprehensive overview of the association between HCC and the immune microenvironment and highlights recent progress in understanding the involvement of mitochondrial function in preserving liver function.In addition,a systematic review of mitokines-mediated immunomodulation in HCC is presented.Finally,the potential diagnostic and therapeutic roles of mitokines in HCC are prospected and summarized.Recent progress in mitokine research represents a new prospect for mitochondrial therapy.Considering the potential of mitokines to regulate immune function,investigating them as a relevant mole cular target holds great promise for the diagnosis and treatment of HCC.

The inhibitory effect of adenosine on tumor adaptive immunity and intervention strategies

Adenosine(Ado)is significantly elevated in the tumor microenvironment(TME)compared to normal tissues.It binds to adenosine receptors(AdoRs),suppressing tumor antigen presentation and immune cell activation,thereby inhibiting tumor adaptive immunity.Ado downregulates major histocompatibility complex II(MHC II)and co-stimulatory factors on dendritic cells(DCs)and macrophages,inhibiting antigen presentation.It suppresses anti-tumor cytokine secretion and T cell activation by disrupting T cell receptor(TCR)binding and signal transduction.Ado also inhibits chemokine secretion and KCa3.1 channel activity,impeding effector T cell trafficking and infiltration into the tumor site.Furthermore,Ado diminishes T cell cytotoxicity against tumor cells by promoting immune-suppressive cytokine secretion,upregulating immune checkpoint proteins,and enhancing immune-suppressive cell activity.Reducing Ado production in the TME can significantly enhance anti-tumor immune responses and improve the efficacy of other immunotherapies.Preclinical and clinical development of inhibitors targeting Ado generation or AdoRs is underway.Therefore,this article will summarize and analyze the inhibitory effects and molecular mechanisms of Ado on tumor adaptive immunity,as well as provide an overview of the latest advancements in targeting Ado pathways in anti-tumor immune responses.

ROS-sensitive PD-L1 siRNA cationic selenide nanogels for self-inhibition of autophagy and prevention of immune escape

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.

Distinct immune escape and microenvironment between RG-like and pri-OPC-like glioma revealed by single-cell RNA-seq analysis

The association of neurogenesis and gliogenesis with glioma remains unclear.By conducting single-cell RNA-seq analyses on 26 gliomas,we reported their classification into primitive oligodendrocyte precursor cell(pri-OPC)-like and radial glia(RG)-like tumors and validated it in a public cohort and TCGA glioma.The RG-like tumors exhibited wild-type isocitrate dehydrogenase and tended to carry EGFR mutations,and the pri-OPC-like ones were prone to carrying TP53 mutations.Tumor subclones only in pri-OPC-like tumors showed substantially down-regulated MHC-I genes,suggesting their distinct immune evasion programs.Furthermore,the two subgroups appeared to extensively modulate glioma-infiltrating lymphocytes in distinct manners.Some specific genes not expressed in normal immune cells were found in glioma-infiltrating lymphocytes.For example,glial/glioma stem cell markers OLIG1/PTPRZ1 and B cell-specific receptors IGLC2/IGKC were expressed in pri-OPC-like and RG-like glioma-infiltrating lymphocytes,respectively.Their expression was positively correlated with those of immune checkpoint genes(e.g.,LGALS33)and poor survivals as validated by the increased expression of LGALS3 upon IGKC overexpression in Jurkat cells.This finding indicated a potential inhibitory role in tumor-infiltrating lymphocytes and could provide a new way of cancer immune evasion.

Immunotherapy in gastric cancer

Gastric cancer is the second most common of cancerrelated deaths worldwide.In the majority of cases gastric cancer is advanced at diagnosis and although medical and surgical treatments have improved,survival rates remain poor.Cancer immunotherapy has emerged as a powerful and promising clinical approach for treatment of cancer and has shown major success in breast cancer,prostate cancer and melanoma.Here,we provide an overview of concepts of modern cancer immunotherapy including the theory,current approaches,remaining hurdles to be overcome,and the future prospect of cancer immunotherapy in the treatment of gastric cancer.Adaptive cell therapies,cancer vaccines,gene therapies,monoclonal antibody therapies have all been used with some initial successes in gastric cancer.However,to date the results in gastric cancer have been disappointing as current approaches often do not stimulate immunity efficiently allowing tumors continue to grow despite the presence of a measurable immune response.Here,we discuss the identification of targets for immunotherapy and the role of biomarkers in prospectively identifying appropriate subjects or immunotherapy.We also discuss the molecular mechanisms by which tumor cells escape host immunosurveillance and produce an immunosuppressive tumor microenvironment.We show how advances have provided tools for overcoming the mechanisms of immunosuppression including the use of monoclonal antibodies to block negative regulators normally expressed on the surface of T cells which limit activation and proliferation of cytotoxic T cells.Immunotherapy has greatly improved and is becoming an important factor in such fields as medical care and welfare for human being.Progress has been rapid ensuring that the future of immunotherapy for gastric cancer is bright.

Alpha-fetoprotein triggers hepatoma cells escaping from immune surveillance through altering the expression of Fas/FasL and tumor necrosis factor related apoptosis-inducing ligand and its receptor of lymphocytes and liver cancer cells

AIM: To investigate the mechanism of α-fetoprotein (AFP)in escaping from the host immune surveillance of hepatocellular carcinoma.METHODS: AFP purified from human umbilical blood was administrated into the cultured human lymphoma Jurkat T cell line or hepatoma cell line, Bel7402 in vitro. The expression of tumor necrosis factor related apoptosisinducing ligand (TRAIL) and its receptor (TRAILR) mRNA were analyzed by Northern blot and Western blot wasused to detect the expression of Fas and Fas ligand (FasL)protein.RESULTS: AFP (20 mg/L) could promote the expression of FasL and TRAIL, and inhibit the expression of Fas and TRAILR of Bel7402 cells. For Jurkat cell line, AFP could suppress the expression of FasL and TRAIL, and stimulate the expression of Fas and TRAILR. AFP also could synergize with Bel7402 cells to inhibit the expression of FasL protein and TRAIL mRNA in Jurkat cells. The monoclonal antibody against AFP (anti-AFP) could abolish these functions of AFP.CONCLUSION: AFP is able to promote the expression of FasL and TRAIL in hepatoma cells and enhance the expression of Fas and TRAILR in lymphocytes. These could elicit the escape of hepatocellular carcinoma cells from the host's lymphocytes immune surveillance.

Expression of calreticulin is associated with infiltration of T-cells in stage ⅢB colon cancer

AIM: To investigate the correlation between expression of calreticulin and infiltration of lymphocytes in stage ⅢB colon cancer. METHODS: Sixty-eight pathologically-confirmed speci-mens were obtained from stage ⅢB (T3N1M0) colon cancer patients who underwent radical resection between January 1999 and May 2002 at the Cancer Center of Sun Yat-Sen University, Guangzhou, China. Immuno-histochemical analysis was performed to show infiltration of lymphocytes and expression of calreticulin in colon cancer. Association between calreticulin expression, infiltration of lymphocytes, and 5-year survival rate of patients was assessed. RESULTS: The expression level of calreticulin was lower in cancer nest than in its adjacent normal epithelium since 61.8% (42/68) of the samples were stained with calreticulin in colon cancer. The expression of calreticulin in colon cancer was associated with the infi ltration of CD45RO+ cells rather than with that of CD3+ cells. In addition, the stronger expression of calreticulin and the higher infiltration of CD3+ and CD45RO+ cells in colon cancer were associated with the higher 5-year survival rate of patients. CONCLUSION: Expression of calreticulin is associated with infiltration of T-cells, which implies that a low expression level of molecular marker may represent a new mechanism underlying immune escape in colon cancer.