Immunotherapies based on immune checkpoint blockade (ICB) have significantly improved patient outcomes and offered new approaches to cancer therapy over the past decade. To date, immune checkpoint inhibitors (ICIs) of CTLA-4 and PD-1/PD-L1 represent the main class of immunotherapy. Blockade of CTLA-4 and PD-1/PD-L1 has shown remarkable efficacy in several specific types of cancers, however, a large subset of refractory patients presents poor responsiveness to ICB therapy; and the underlying mechanism remains elusive. Recently, numerous studies have revealed that metabolic reprogramming of tumor cells restrains immune responses by remodeling the tumor microenvironment (TME) with various products of metabolism, and combination therapies involving metabolic inhibitors and ICIs provide new approaches to cancer therapy. Nevertheless, a systematic summary is lacking regarding the manner by which different targetable metabolic pathways regulate immune checkpoints to overcome ICI resistance. Here, we demonstrate the generalized mechanism of targeting cancer metabolism at three crucial immune checkpoints (CTLA-4, PD-1, and PD-L1) to influence ICB therapy and propose potential combined immunotherapeutic strategies co-targeting tumor metabolic pathways and immune checkpoints.
Humans ; Antibodies, Monoclonal/pharmacology* ; B7-H1 Antigen/antagonists & inhibitors* ; CTLA-4 Antigen/antagonists & inhibitors* ; Immune Checkpoint Inhibitors/pharmacology* ; Neoplasms/drug therapy* ; Programmed Cell Death 1 Receptor ; Tumor Microenvironment

OBJECTIVE: To observe the effects of drug-containing serum of Xijiao Dihuang combined prescription(XJDH) on the related functions of dendritic cells(DCs) induced in vitro, and to explore the mechanisms underlying the effectiveness of XJDH treatment on primary immune thrombocytopenia(ITP). METHODS: Peripheral blood samples were colle-ted from 6 healthy volunteers. Mononuclear cells were isolated by density gradient centrifugation, and CD14⁺ mononuclear cells were collected by the magnetic separation technique. CD14+ mononuclear cells were induced into immature DCs by recombinant human granulocyte-macrophage colony stimulating factor (GM-CSF) and recombinant human interleukin 4 (IL-4). Immature DCs were divided into three groups: control group, model group and XJDH group. CCK-8 assay was used to determine the intervention concentration and time of drug-containing serum. Lipopolysaccharide(LPS) with the final concentration of 1 μg/ml was added to model group and XJDH group respectively for 24 h to induce DCs maturation. Normal rat serum was added to control group and model group, and XJDH was added to XJDH group for 24 h. Flow cytometry was used to detect the levels of CD80, CD83 and HLA-DR on the surface of DCs. Western blot was used to detect the expression of TLR4 and NF-κB, and levels of IL-6, IL-12 and TNF-α in cell supernatant was detected by ELISA. RESULTS: Compared with the control group, LPS stimulation increased the expression of CD80, CD83 and HLA-DR, with subsequent increasing expression of TLR4 and NF-κB, as well as IL-6, IL-12 and TNF-α increased(P<0.05). In comparison with model group, the expression of DCs surface molecules CD80, CD83 and HLA-DR, DCs' expression of TLR4 and NF-κB protein, and the levels of IL-6, IL-12 and TNF-α in the cell supernatant of XJDH group decreased after the intervention of XJDH (P<0.05). CONCLUSION Drug containing serum of Xijiao Dihuang combined prescription can down-regulate TLR4/NF-κB signaling pathway related protein expression, inhibit DCs maturation, and reduce proinflammatory factor secretion, which may be one of the mechanisms of drug-containing serum of Xijiao Dihuang combined prescription in the treatment of immune thrombocytopenia.
Animals ; B7-1 Antigen/pharmacology* ; Cell Differentiation ; Dendritic Cells ; HLA-DR Antigens/pharmacology* ; Humans ; Interleukin-12/pharmacology* ; Interleukin-6 ; Lipopolysaccharides/pharmacology* ; Medicine, Chinese Traditional ; NF-kappa B ; Prescriptions ; Purpura, Thrombocytopenic, Idiopathic ; Rats ; Toll-Like Receptor 4 ; Tumor Necrosis Factor-alpha/pharmacology*

Interferon-γ (IFN-γ), a key effector molecule in anti-tumor immune response, has been well documented to correlate with the intratumoral infiltration of immune cells. Of interest, however, a high level of IFN-γ has been reported in salivary adenoid cystic carcinoma (SACC), which is actually a type of immunologically cold cancer with few infiltrated immune cells. Investigating the functional significance of IFN-γ in SACC would help to explain such a paradoxical phenomenon. In the present study, we revealed that, compared to oral squamous cell carcinoma cells (a type of immunologically hot cancer), SACC cells were less sensitive to the growth-inhibition effect of IFN-γ. Moreover, the migration and invasion abilities of SACC cells were obviously enhanced upon IFN-γ treatment. In addition, our results revealed that exposure to IFN-γ significantly up-regulated the level of programmed death ligand 1 (PD-L1) on SACC cell-derived small extracellular vesicles (sEVs), which subsequently induced the apoptosis of CD8⁺ T cells through antagonizing PD-1. Importantly, it was also found that SACC patients with higher levels of plasma IFN-γ also had higher levels of circulating sEVs that carried PD-L1 on their surface. Our study unveils a mechanism that IFN-γ induces immunosuppression in SACC via sEV PD-L1, which would account for the scarce immune cell infiltration and insensitivity to immunotherapy.
B7-H1 Antigen/metabolism* ; CD8-Positive T-Lymphocytes/pathology* ; Carcinoma, Adenoid Cystic/pathology* ; Carcinoma, Squamous Cell/pathology* ; Cell Line, Tumor ; Humans ; Immunosuppression Therapy ; Interferon-gamma/pharmacology* ; Mouth Neoplasms/metabolism* ; Programmed Cell Death 1 Receptor/metabolism* ; Salivary Gland Neoplasms/pathology*

Programmed cell death-1 (PD-1)/programmed cell death-ligand 1 (PD-L1) checkpoint blockades have dramatically changed the treatment of non-small cell lung cancer (NSCLC). But we still have no definite biomarkers that may predict the efficacy of treatment by PD-1/PD-L1 inhibitors. In the 18th World Conference on Lung Cancer, the biomarkers that may predict the efficacy of treatment by PD-1/PD-L1 inhibitors in patients with lung cancer has been a popular topic, and it has huge potential in the future. In order to enable more patients to get more benefits from treatment, researchers are looking forward to finding the optimum biomarkers. By organizing and summarizing the information about the biomarkers predicting PD-1/PD-L1 in patients with lung cancer, this review mainly focused on the following six aspects to introduce: expression of PD-L1; tumor mutational burden and the ability of mutation repair, malignant tumor driver mutation, biomarker of immunological effect, blood cell account, comprehensive analysis model. We are hoping to help doctors to find the best biomarker, then much more lung cancer patients could obtain antitumor effects in PD-1/PD-L1 inhibitors treatment.
.
Antineoplastic Agents ; pharmacology ; therapeutic use ; B7-H1 Antigen ; antagonists & inhibitors ; Biomarkers, Tumor ; metabolism ; Carcinoma, Non-Small-Cell Lung ; drug therapy ; genetics ; metabolism ; Humans ; Lung Neoplasms ; drug therapy ; genetics ; metabolism ; Programmed Cell Death 1 Receptor ; antagonists & inhibitors

Dendritic cells (DCs) are crucial for the induction and maintenance of tumor-specific immune responses. Studies have shown that tumor-associated DCs are immunosuppressed in some human tumors. However, phenotype and function of DCs in retinoblastoma (RB) remain unclear. RB cell supernatant (RBcs) was used to treat DCs in vitro to explore the effect of RB cells on DCs. DCs were generated from peripheral blood mononuclear cells of healthy donors. On day 5 of culture, DCs were treated with RBcs for 24 h, and then purified using magnetic beads. The maturation of DCs was induced by TNF-α or LPS. After treatment with RBcs, expression of co-stimulatory molecules CD80 and CD86 was elevated in DCs, accompanied by increased production of IL-12p70, TNF-α, IL-6, IL-1β, and IL-8 but decreased production of IL-10. RBcs neither inhibited DC maturation nor promoted DC apoptosis. Moreover, RBcs-exposed DCs stimulated allogenetic T cell proliferation and T cell-derived cytokine production. These results indicate that RBcs can improve DCs' antigen presenting function and capability to activate T cells, suggesting that RB cells may have an immunostimulatory effect on DCs, and DC-based immunotherapy may be adopted in the treatment of RB.
B7-1 Antigen ; metabolism ; B7-2 Antigen ; metabolism ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Culture Media, Conditioned ; pharmacology ; Cytokines ; metabolism ; Dendritic Cells ; drug effects ; immunology ; metabolism ; Humans ; Lipopolysaccharides ; toxicity ; Retinal Neoplasms ; metabolism ; pathology ; Retinoblastoma ; metabolism ; pathology ; T-Lymphocytes ; cytology ; immunology ; metabolism ; Tumor Necrosis Factor-alpha ; pharmacology

OBJECTIVETo compare the effects of Bushen Jiedu Recipe (BJR) and Jianpi Jiedu Recipe (JJR) containing plasma on dendritic cells (DCs) of chronic hepatitis B virus (HBV) infection patients under different immune states.

METHODSRecruited were 36 chronic HBV infection outpatients from First Affiliated Hospital of Hunan University of Traditional Chinese Medicine from April 2010 to January 2011. They were assigned to the immune tolerance group (18 cases) and the immune clearance group (18 cases).Another 10 healthy subjects were recruited as the healthy control group. Their anticoagulated peripheral venous blood was respectively collected. The peripheral blood mononuclear cells (PBMCs) were isolated and further extracted for incubating DCs. The DCs were intervened by BJR and JJR containing plasma. The morphology of DCs was identified. The expressions of CD1alpha, CD80, CD86, and HLA-DR were detected. The level of interferon-alpha (IFN-alpha) in the supernatant was observed by ELISA.

RESULTSThe CD80 expression level was lower in the immune clear group than in the healthy control group before intervention (P < 0.05). The expression levels of CD80, CD86, and HLA-DR were lower in the immune tolerance group than in the healthy control group before intervention (P < 0.05).The IFN-alpha expression level was lower in the immune tolerance group and the immune clearance group than in the healthy control group before intervention (P < 0.05). The expression levels of CD80, HLA-DR, and IFN-alpha were lower in the immune tolerance group than in the immune clearance group before intervention (P < 0.05). Compared with the same group before intervention, the CD80 expression significantly increased in each treatment group (P < 0.05). After intervention the expression levels of CD80 and HLA-DR were higher in the immune tolerance group than in the immune clearance group in the same time phase, and the CD86 expression level was higher in the BJR group than in the immune clearance group in the same time phase, showing statistical difference (P < 0.05).

CONCLUSIONSThe middle dose BJR and the small dose JJR both could promote the recovery of DCs in chronic HBV infection patients. Besides, BJR showed more prominent effects on the function of DCs in chronic HBV infection patients in the immune tolerance stage.

Adult ; B7-1 Antigen ; metabolism ; B7-2 Antigen ; metabolism ; Case-Control Studies ; Dendritic Cells ; drug effects ; immunology ; Drugs, Chinese Herbal ; pharmacology ; therapeutic use ; Female ; HLA-DR Antigens ; metabolism ; Hepatitis B, Chronic ; blood ; drug therapy ; immunology ; Humans ; Immune Tolerance ; drug effects ; Interferon-alpha ; metabolism ; Male ; Phytotherapy ; Plasma ; Young Adult

OBJECTIVETo explore the anti-tumor mechanism of the combination of cisplatin with DC vaccine in tumor-bearing mice.

METHODSB16 melanoma cells were treated with cisplatin at the final concentration of 20 µg/ml in vitro for 24 h. The expression of HMGB1, Hsp70 and TGF-β were detected by Western blot. B16 tumor-bearing mouse models were generated. The therapeutic effect of the combination of cisplatin (100 µg/mouse i.p., for sequential 3 days) and intratumoral injection of DC cells (3×10(6)/mouse, twice with a 7-day interval) in the tumor-bearing mouse models was evaluated. Expression of MHC II, ICAM-1 and CD86 was analyzed by flow cytometry. The mice were sacrificed at 28 days after tumor cell inoculation. The tumors were removed and weighed, and tissue samples were taken for pathological examination. Tumor infiltrating lymphocytes (TIL) were isolated by discontinuous gradient centrifugation. The distribution of T-reg and CD8(+) T cells in the TIL was analyzed by flow cytometry, and the ratio of CD8(+) T/T-reg was determined. The activity of cytotoxic lymphocytes (CTL) was determined by microcytotoxicity assay.

RESULTSCisplatin enhanced both the B16 cell apoptosis and HMGB1 expression. After loading with cisplatin-treated cell lysate, the expression of MHC II, ICAM-1 and CD86 on DC cells were (47.5 ± 8.8)%, (35.5 ± 8.3)% and (36.2 ± 9.2)%, respectively. At 28 days after tumor cell inoculation, the tumor weight of the control group was (2.1 ± 0.6) g, that of the cisplatin group was (0.3 ± 0.2) g and that of cisplatin + DC vaccine group was (0.5 ± 0.2) g, showing a significant inhibition of tumor growth (P < 0.01). Furthermore, the CD8(+) T/T-reg ratio and CTL activity in TIL were also significantly enhanced in the tumor-bearing mice treated with cisplatin + DC vaccine. When the effector-to-target ratio was 20:1, 10:1 and 5:1, the CTL activity in the cisplatin + DC vaccine treated mice was (25.0 ± 5.0)%, (22.0 ± 6.0)% and (14.0 ± 4.0)%, respectively, significantly higher than (8.2 ± 3.6)%, (6.7 ± 1.8)% and (3.6 ± 1.9)%, respectively, in the control group (all P < 0.01).

CONCLUSIONCisplatin promotes the anti-tumor effect of DC vaccine by down-regulating T-reg cells and enhancing the CTL activity in tumors.

Animals ; Antineoplastic Agents ; pharmacology ; Apoptosis ; drug effects ; B7-2 Antigen ; metabolism ; CD8-Positive T-Lymphocytes ; pathology ; Cancer Vaccines ; pharmacology ; Cell Line, Tumor ; Cisplatin ; pharmacology ; Dendritic Cells ; immunology ; metabolism ; Female ; Genes, MHC Class II ; HMGB1 Protein ; metabolism ; Intercellular Adhesion Molecule-1 ; metabolism ; Melanoma, Experimental ; pathology ; Mice ; Mice, Inbred C57BL ; Neoplasm Transplantation ; T-Lymphocytes, Cytotoxic ; immunology ; T-Lymphocytes, Regulatory ; pathology ; Tumor Burden ; drug effects

OBJECTIVETo explore the mechanism of polypeptide extract from scorpion venom (PESV) on promoting anti-tumor effects of cyclophosphamide (CTX).

METHODSThe Lewis lung tumor model was established by subcutaneously implanting Lewis lung cells into C57BL/6 mice. The tumor-bearing mice were randomly divided into 4 groups, i. e., the model group, the cyclophosphamide (CTX) group, the polypeptide extract from scorpion venom (PESV) group, and the combination group (CTX + PESV), 10 mice in each group. The tumor growth curve was recorded. Changes of vascular endothelial growth factor-A (VEGF-A) and transforming growth factor-beta1 (TGF-beta1) expressions in the tumor microenvironment were detected using reverse transcription PCR and immunohistochemical assay. Changes of dendritic cells (DCs) phenotype CD80 and CD86 expressions in the tumor tissue were detected using immunofluorescence chemical assay.

RESULTSAfter 21 successive days of treatment, the growth of Lewis lung cancer transplantation tumor in the combination group was obviously inhibited (P<0.05). Compared with the model group,the expressions of CD80 and CD86 in the PESV group was somewhat enhanced, while those in the CTX group was somewhat lowered. Compared with the CTX group, the fluorescent signal strength and expressions in the combination group somewhat increased. Compared with the model group, the expressions of TGF-beta1 and VEGF-A mRNA decreased in the PESV group and the CTX group (both P<0.05). Compared with the PESV group and the CTX group, the expressions of TGF-beta1 and VEGF-A in the combination group both decreased (both P<0.05).

CONCLUSIONPESV could inhibit the expressions of VEGF and TGF-beta1, promote the maturation of DCs, recover its antigen uptake presentation function, and reverse the immune injury to the body by CTX, thus playing a role in inducing the tumor cell apoptosis.

Animals ; B7-1 Antigen ; B7-2 Antigen ; Carcinoma, Lewis Lung ; immunology ; metabolism ; pathology ; Cyclophosphamide ; pharmacology ; Dendritic Cells ; immunology ; Lung Neoplasms ; metabolism ; pathology ; Male ; Mice ; Mice, Inbred C57BL ; Peptides ; pharmacology ; Scorpion Venoms ; pharmacology ; Transforming Growth Factor beta1 ; metabolism ; Vascular Endothelial Growth Factor A ; metabolism

OBJECTIVETo study the ex vivo effect of sirolimus on capacity of splenic dendritic cells (DC) from traumatized mice in inducing T cell responses.

METHODSTwenty-four BALB/c mice were divided into control group and trauma group according to the random number table, with 12 mice in each group. Mice in trauma group were bled followed by closed femur fracture after anaesthesia, while mice in control group were only anaesthetized without injury. Twenty-four hours later DC were isolated from spleens and divided into 4 subgroups: sirolimus devoid control (trauma) groups [consisted of cells from control (trauma) groups, without sirolimus treatment] and sirolimus treated control (trauma) groups [consisted of cells from control (trauma) groups, treated with 10 microg/L sirolimus for 6 hours]. Then their autophagic activity, DC-induced mixed lymphocyte reaction (MLR) were measured and recorded as fluorescence intensity (FI) value and absorbance value respectively. The expression of major histocompatibility complex class (MHC) II and costimulatory molecules CD40, CD80, and CD86 on DC surface were measured with flow cytometry. IL-12p40, IL-12p70 and IL-10 levels in lipopolysaccharide-stimulated DC supernatants were determined by ELISA. Data were processed with one-way analysis of variance.

RESULTS(1) Compared with those of sirolimus devoid control group (FI value = 22 +/- 6), DC autophagic activity (FI value = 13 +/- 2) and DC-induced MLR in mice from sirolimus devoid trauma group were significantly weakened (F = 212.836, P < 0.05). Compared with those of sirolimus devoid control (trauma) groups, DC autophagic activity in mice from sirolimus treated control (trauma) groups (FI = 45 +/- 8, 44 +/- 8 respectively) were significantly strengthened (F = 212.836, P < 0.05 or P < 0.01). MLR in mice from sirolimus treated trauma group was stronger than that from sirolimus devoid trauma group (with F value respectively 101.426, 86.533, P values all below 0.05). (2) Compared with those of sirolimus devoid control group [MHC II (85 +/- 6)%, CD40 (8 +/- 1)%], the expressions of MHCII [(60 +/- 9)%] and CD40 [(4 +/- 1)%] on DC surface from sirolimus devoid trauma group were significantly reduced (with F value respectively 37.918, 40.426, P values all below 0.05). The expression of MHCII from sirolimus treated trauma group [(78 +/- 7)%] was higher than that from sirolimus devoid trauma group (F = 37.918, P < 0.05). (3) IL-12p40, IL-12p70 secretion by DC from sirolimus devoid trauma group [(120 +/- 13), (10 +/- 3) pg/mL] were significantly reduced as compared with those from sirolimus devoid control group [(200 +/- 25), (20 +/- 6) pg/mL, with F value respectively 218.646, 310.253, P values all below 0.05]. Compared with those from sirolimus devoid control (trauma) groups, IL-12p40 [(560 +/- 34), (540 +/- 29) pg/mL], IL-12p70 [(55 +/- 8), (60 +/- 11) pg/mL] secretion by DC from sirolimus treated control (trauma) groups were obviously enhanced (with F value respectively 218.646, 310.253, P values all below 0.01), while IL-10 secretion levels were significantly decreased (F = 246.108, P < 0.01).

CONCLUSIONSSirolimus can partially ameliorate DC functions ex vivo in traumatized mice, and further enhance the capacity of DC in inducing T cell responses.

Animals ; B7-1 Antigen ; metabolism ; B7-2 Antigen ; metabolism ; CD40 Antigens ; metabolism ; Dendritic Cells ; drug effects ; immunology ; metabolism ; Histocompatibility Antigens Class II ; immunology ; Interleukin-12 Subunit p40 ; metabolism ; Lymphocyte Culture Test, Mixed ; Male ; Mice ; Mice, Inbred BALB C ; Sirolimus ; pharmacology ; Spleen ; cytology ; immunology ; T-Lymphocytes ; immunology ; Wounds and Injuries ; immunology

BACKGROUNDDendritic cells (DCs) are one of the most important antigen presenting cells in the human body, and DCs at various stages of maturation possess different or even opposite functions. The aim of this study was to investigate the influence of growth hormones on the functional status of cord blood-derived DCs encompassing immunophenotype, ability to excrete interleukin (IL)-12 and provoke autologous leukomonocyte.

METHODSMononuclear cells were isolated from fresh cord blood, with IL-4 and granulocyte-macrophage colony-stimulating factor (GM-CSF) used to induce and stimulate the mononuclear cells. Growth hormone at different concentrations was used to modify DCs, and then DCs morphology, number and growth status were observed. The immunophenotype of DCs was detected with a flow cytometer. The concentration of IL-12 in the DCs supernatant was determined by enzyme linked immunosorbent assay (ELISA) and DCs functional status was evaluated by autologous mixed lymphocyte reactions.

RESULTSMononuclear cells from cord blood can be differentiated into DCs by cytokine induction and growth hormone modification. With the increase in growth hormone concentrations (5 - 100 microg/L), the expression of DCs HLA-DR, CD1alpha, CD80 and CD83 were significantly increased (P < 0.05). The ability of DCs to secrete IL-12 was significantly improved (P < 0.05), and the ability of DCs to activate autologous lymphocytes was significantly enhanced (P < 0.05). Pegvisomant was able to ablate the effects of growth hormone on DCs.

CONCLUSIONSGrowth hormone may facilitate DCs induction and maturation, and improve the reproductive activity of autologous lymphocytes in a dose-dependent manner. Growth hormone may serve as a factor of modifying DCs to achieving maturity.

Antigens, CD ; metabolism ; B7-1 Antigen ; metabolism ; Cells, Cultured ; Dendritic Cells ; drug effects ; metabolism ; Enzyme-Linked Immunosorbent Assay ; Flow Cytometry ; Granulocyte-Macrophage Colony-Stimulating Factor ; metabolism ; Growth Hormone ; pharmacology ; HLA-DR Antigens ; metabolism ; Humans ; Immunoglobulins ; metabolism ; Interleukin-12 ; metabolism ; Membrane Glycoproteins ; metabolism