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1.
Aging (Albany NY) ; 15(6): 1890-1917, 2023 02 19.
Article in English | MEDLINE | ID: mdl-36812472

ABSTRACT

Hypertensive heart disease presents increasing morbidity and mortality worldwide, however, the data about its epidemics and its specific symptoms in hypertension patients is scarce. To assess the frequency and correlated symptoms of hypertensive heart disease, 800 hypertension patients were randomly recruited for this study per the guidelines of the American College of Cardiology. The diagnosis of heart disease and its typical symptoms (palpitation and angina) were analyzed for the frequency of hypertensive heart disease in hypertension cohort. Cross-tabulation analysis was used to study the correlation between psychiatric indexes (annoy, amnesia, irritableness, depression, anxiety, and fear) and palpitation, the correlation between physical disorders (backache, lumbar debility, and numbness of limbs) and palpitation, and the correlation between symptoms (dizziness, daze, headache, and tinnitus) and palpitation presented in hypertensive patients. It was found that around half of patients suffered hypertensive heart disease, which correlated to certain physical and mental symptoms. Significant correlation exists between palpitation and annoy / amnesia. Significant correlation exists between palpitation and backache / lumbar debility / numbness of limbs; and significant correlation exists between palpitation and dizziness / daze / headache / tinnitus. These results provide clinical insights into the modifiable antecedent clinical conditions which are risk factors for hypertensive heart disease in elderly and will help improve early management of this disease.


Subject(s)
Frailty , Hypertension , Tinnitus , Humans , Aged , Dizziness/complications , Tinnitus/complications , Frailty/complications , Hypesthesia/complications , Hypertension/complications , Hypertension/epidemiology , Hypertension/diagnosis , Angina Pectoris , Headache/etiology
2.
Nat Commun ; 14(1): 228, 2023 01 16.
Article in English | MEDLINE | ID: mdl-36646715

ABSTRACT

The interplay between western diet and gut microbiota drives the development of non-alcoholic fatty liver disease and its progression to non-alcoholic steatohepatitis. However, the specific microbial and metabolic mediators contributing to non-alcoholic steatohepatitis remain to be identified. Here, a choline-low high-fat and high-sugar diet, representing a typical western diet, named CL-HFS, successfully induces male mouse non-alcoholic steatohepatitis with some features of the human disease, such as hepatic inflammation, steatosis, and fibrosis. Metataxonomic and metabolomic studies identify Blautia producta and 2-oleoylglycerol as clinically relevant bacterial and metabolic mediators contributing to CL-HFS-induced non-alcoholic steatohepatitis. In vivo studies validate that both Blautia producta and 2-oleoylglycerol promote liver inflammation and hepatic fibrosis in normal diet- or CL-HFS-fed mice. Cellular and molecular studies reveal that the GPR119/TAK1/NF-κB/TGF-ß1 signaling pathway mediates 2-oleoylglycerol-induced macrophage priming and subsequent hepatic stellate cell activation. These findings advance our understanding of non-alcoholic steatohepatitis pathogenesis and provide targets for developing microbiome/metabolite-based therapeutic strategies against non-alcoholic steatohepatitis.


Subject(s)
Gastrointestinal Microbiome , Non-alcoholic Fatty Liver Disease , Animals , Male , Mice , Diet, High-Fat/adverse effects , Diet, Western/adverse effects , Disease Models, Animal , Inflammation/pathology , Liver/metabolism , Mice, Inbred C57BL , Non-alcoholic Fatty Liver Disease/metabolism , Receptors, G-Protein-Coupled/metabolism
3.
Cells ; 11(22)2022 11 19.
Article in English | MEDLINE | ID: mdl-36429112

ABSTRACT

Both preclinical and clinical studies have demonstrated that the modulation of gut microbiota could be a promising strategy for enhancing antitumor immune responses and reducing resistance to immunotherapy in cancer. Various mechanisms, including activation of pattern recognition receptors, gut commensals-produced metabolites and antigen mimicry, have been revealed. Different gut microbiota modulation strategies have been raised, such as fecal microbiota transplantation, probiotics, and dietary selection. However, the identification of gut bacteria species that are either favorable or unfavorable for cancer therapy remains a major challenge. Herein, we summarized the findings related to gut microbiota species observed in the modulation of antitumor immunity. We also discussed the different mechanisms underlying different gut bacteria's functions and the potential applications of these bacteria to cancer immunotherapy in the future.


Subject(s)
Gastrointestinal Microbiome , Neoplasms , Probiotics , Humans , Gastrointestinal Microbiome/physiology , Fecal Microbiota Transplantation , Bacteria , Probiotics/therapeutic use , Neoplasms/therapy
4.
FASEB J ; 36(4): e22250, 2022 04.
Article in English | MEDLINE | ID: mdl-35294071

ABSTRACT

Combination therapy represents an effective therapeutic approach to overcome hepatocellular cancer (HCC) resistance to immune checkpoint blockade (ICB). Based upon previous work demonstrating that nanoliposome C6-ceramide (LipC6) not only induces HCC apoptosis but also prevents HCC-induced immune tolerance, we now investigate the potential of LipC6 in combination with ICB in HCC treatment. We generated orthotopic HCC-bearing mice, which have typical features in common with human patients, and then treated them with LipC6 in combination with the antibodies (Abs) for programmed cell death protein 1 (PD-1) or cytotoxic T-lymphocyte antigen 4 (CTLA4). The tumor growth was monitored by magnetic resonance imaging (MRI) and the intrahepatic immune profiles were checked by flow cytometry in response to the treatments. Realtime PCR (qPCR) was used to detect the expression of target genes. The results show that LipC6 in combination with anti-CTLA4 Ab, but not anti-PD-1 Ab, significantly slowed tumor growth, enhanced tumor-infiltrating CD8+ T cells, and suppressed tumor-resident CD4+ CD25+ FoxP3+ Tregs. Further molecular investigation indicates that the combinational treatment suppressed transcriptional factor Krüppel-like Factor 2 (KLF2), forkhead box protein P3 (FoxP3), and CTLA4. Our studies suggest that LipC6 in combination with anti-CTLA4 Ab represents a novel therapeutic approach with significant potential in activating anti-HCC immune response and suppressing HCC growth.


Subject(s)
Antineoplastic Agents , Carcinoma, Hepatocellular , Liver Neoplasms , Animals , Antineoplastic Agents/pharmacology , CD8-Positive T-Lymphocytes , CTLA-4 Antigen , Carcinoma, Hepatocellular/metabolism , Ceramides , Forkhead Transcription Factors/metabolism , Humans , Liver Neoplasms/metabolism , Mice
5.
Biomedicines ; 9(12)2021 Dec 13.
Article in English | MEDLINE | ID: mdl-34944709

ABSTRACT

Nonalcoholic fatty liver disease (NAFLD) with pathogenesis ranging from nonalcoholic fatty liver (NAFL) to the advanced form of nonalcoholic steatohepatitis (NASH) affects about 25% of the global population. NAFLD is a chronic liver disease associated with obesity, type 2 diabetes, and metabolic syndrome, which is the most increasing factor that causes hepatocellular carcinoma (HCC). Although advanced progress has been made in exploring the pathogenesis of NAFLD and penitential therapeutic targets, no therapeutic agent has been approved by Food and Drug Administration (FDA) in the United States. Gut microbiota-derived components and metabolites play pivotal roles in shaping intrahepatic immunity during the progression of NAFLD or NASH. With the advance of techniques, such as single-cell RNA sequencing (scRNA-seq), each subtype of immune cells in the liver has been studied to explore their roles in the pathogenesis of NAFLD. In addition, new molecules involved in gut microbiota-mediated effects on NAFLD are found. Based on these findings, we first summarized the interaction of diet-gut microbiota-derived metabolites and activation of intrahepatic immunity during NAFLD development and progression. Treatment options by targeting gut microbiota and important molecular signaling pathways are then discussed. Finally, undergoing clinical trials are selected to present the potential application of treatments against NAFLD or NASH.

6.
Front Cell Dev Biol ; 9: 647387, 2021.
Article in English | MEDLINE | ID: mdl-33763427

ABSTRACT

Pancreatic cancer (PC) is one of the most lethal human malignancies without effective treatment. In an effort to discover key genes and molecular pathways underlying PC growth, we have identified LIM domain only 7 (LMO7) as an under-investigated molecule, which highly expresses in primary and metastatic human and mouse PC with the potential of impacting PC tumorigenesis and metastasis. Using genetic methods with siRNA, shRNA, and CRISPR-Cas9, we have successfully generated stable mouse PC cells with LMO7 knockdown or knockout. Using these cells with loss of LMO7 function, we have demonstrated that intrinsic LMO7 defect significantly suppresses PC cell proliferation, anchorage-free colony formation, and mobility in vitro and slows orthotopic PC tumor growth and metastasis in vivo. Mechanistic studies demonstrated that loss of LMO7 function causes PC cell-cycle arrest and apoptosis. These data indicate that LMO7 functions as an independent and unrecognized druggable factor significantly impacting PC growth and metastasis, which could be harnessed for developing a new targeted therapy for PC.

7.
Materials (Basel) ; 14(4)2021 Feb 15.
Article in English | MEDLINE | ID: mdl-33671967

ABSTRACT

Graphene's outstanding properties make it a potential material for reinforced cementitious composites. However, its shortcomings, such as easy agglomeration and poor dispersion, severely restrict its application in cementitious materials. In this paper, a highly dispersible graphene (TiO2-RGO) with better dispersibility compared with graphene oxide (GO) is obtained through improvement of the graphene preparation method. In this study, both GO and TiO2-RGO can improve the pore size distribution of cement mortars. According to the results of the mercury intrusion porosity (MIP) test, the porosity of cement mortar mixed with GO and TiO2-RGO was reduced by 26% and 40%, respectively, relative to ordinary cement mortar specimens. However, the TiO2-RGO cement mortars showed better pore size distribution and porosity than GO cement mortars. Comparative tests on the strength and durability of ordinary cement mortars, GO cement mortars, and TiO2-RGO cement mortars were conducted, and it was found that with the same amount of TiO2-RGO and GO, the TiO2-RGO cement mortars have nearly twice the strength of GO cement mortars. In addition, it has far higher durability, such as impermeability and chloride ion penetration resistance, than GO cement mortars. These results indicate that TiO2-RGO prepared by titanium dioxide (TiO2) intercalation can better improve the strength and durability performance of cement mortars compared to GO.

8.
J Immunother Cancer ; 8(2)2020 10.
Article in English | MEDLINE | ID: mdl-33115942

ABSTRACT

BACKGROUND: Minimally invasive radiofrequency ablation (RFA) is used as a first-line treatment option for hepatocellular cancer (HCC) with the weaknesses of incomplete ablation, tumor recurrence, and inferior outcomes. To overcome this limitation, we proposed to develop sunitinib-RFA integrated therapy with a potential of activating anti-HCC immune response. METHODS: Using our unique murine model, we developed a novel RFA platform with a modified human cardiac RF generator. Therapeutic efficacy of sunitinib-RFA combined treatment in HCC was tested in this platform. Tumor progression was monitored by MRI; tumor necrosis and apoptosis were detected by H&E and terminal deoxynucleotidyl transferase dUTP nick end labeling; immune reaction was defined by flow cytometry; and signaling molecules were examined with real-time PCR (qPCR), western blot, and immunohistochemical staining. RESULTS: A significantly reduced tumor growth and extended lift span were observed in the mice receiving combined treatment with RFA and sunitinib. This combined treatment significantly increased the frequency of CD8+ T cell, memory CD8+ T cell, and dendritic cells (DCs); decreased the frequency of regulatory T cells; and activated tumor-specific antigen (TSA) immune response in tumor microenvironment. We found that RFA caused PD-1 upregulation in tumor-infiltrated T cells by boosting hepatocyte growth factor (HGF) expression, which was suppressed by sunitinib treatment. We have also demonstrated that sunitinib suppressed VEGF's effect in enhancing PD-L1 expression in DCs and attenuated heat-sink effect. The results indicate that RFA induced tumor destruction and release of in situ TSAs which can activate a tumoricidal immune response in sunitinib-treated mice, significantly improving anti-HCC therapeutic efficacy. CONCLUSIONS: Sunitinib enables RFA-released in situ TSA to ignite an effective anti-tumor immune response by suppressing HGF and VEGF signaling pathways. Sunitinib-RFA as a synergistic therapeutic approach significantly suppresses HCC growth.


Subject(s)
Carcinoma, Hepatocellular/radiotherapy , Dendritic Cells/metabolism , Immunity/immunology , Liver Neoplasms/radiotherapy , Radiofrequency Ablation/methods , Sunitinib/therapeutic use , Animals , Disease Models, Animal , Humans , Mice , Sunitinib/pharmacology
9.
Front Pharmacol ; 11: 386, 2020.
Article in English | MEDLINE | ID: mdl-32317968

ABSTRACT

Trichomicin, a small-molecule compound isolated from fungi, has been identified with bioactivity of antitumor. In this study, a colon cancer subcutaneous mice model was used to evaluate the antitumor effects of Trichomicin in vivo. Treatment with Trichomicin significantly inhibited tumor growth in a xenograft mouse colon cancer model. The underlying molecular mechanism has also been investigated through the quantification of relevant proteins. The expression levels of IL-6 and TNFα were reduced in tumor tissues of mice treated with Trichomicin, which was consistent with results of in vitro experiments in which Trichomicin suppressed the expression of IL-6 and TNFα in tumor and stromal cells. In addition, Trichomicin inhibited TNFα-induced activation of NF-κB and basal Stat3 signaling in vitro, which resulted in reduced expression of the immune checkpoint protein PD-L1 in tumor and stromal cells. Conclusively, Trichomicin, a promising new drug candidate with antitumor activity, exerted antitumor effects against colon cancer through inhibition of the IL-6 and TNFα signaling pathways.

10.
World J Gastroenterol ; 26(48): 7603-7618, 2020 Dec 28.
Article in English | MEDLINE | ID: mdl-33505139

ABSTRACT

Gut microbiota is a community of microorganisms that reside in the gastrointestinal tract. An increasing number of studies has demonstrated that the gut-liver axis plays a critical role in liver homeostasis. Dysbiosis of gut microbiota can cause liver diseases, including nonalcoholic fatty liver disease and alcoholic liver disease. Preclinical and clinical investigations have substantiated that the metabolites and other molecules derived from gut microbiota and diet interaction function as mediators to cause liver fibrosis, cirrhosis, and final cancer. This effect has been demonstrated to be associated with dysregulation of intrahepatic immunity and liver metabolism. Targeting these findings have led to the development of novel preventive and therapeutic strategies. Here, we review the cellular and molecular mechanisms underlying gut microbiota-mediated impact on liver disease. We also summarize the advancement of gut microbiota-based therapeutic strategies in the control of liver diseases.


Subject(s)
Gastrointestinal Microbiome , Non-alcoholic Fatty Liver Disease , Probiotics , Dysbiosis , Humans , Liver , Non-alcoholic Fatty Liver Disease/therapy , Probiotics/therapeutic use
11.
Biomed Pharmacother ; 121: 109608, 2020 Jan.
Article in English | MEDLINE | ID: mdl-31707338

ABSTRACT

Trichomicin, a novel small-molecule compound isolated from the fungus Trichoderma harzianum and identified as new structure compound, exhibited antitumor activities in various human cancer cell lines and reversed drug resistance activity in the multidrug-resistant cancer cell line KBV. The underlying cellular and molecular mechanism was illuminated. Trichomicin can significantly induce cancer cell apoptosis and reduced IL-6 expression and phosphorylation of STAT3 were found in response to Trichomicin treatment. The blockade of IL-6 mediated JAK-STAT3 signaling pathway by Trichomicin was confirmed using reporter gene system. As a promising antitumor-activity compound, Trichomicin is presented in this study.


Subject(s)
Antineoplastic Agents/isolation & purification , Hypocreales/chemistry , STAT3 Transcription Factor/antagonists & inhibitors , Animals , Antineoplastic Agents/pharmacology , Antineoplastic Agents/toxicity , Apoptosis/drug effects , Cell Line, Tumor , Drug Resistance, Neoplasm , Humans , Interleukin-6/antagonists & inhibitors , Mice , Phosphorylation , STAT3 Transcription Factor/physiology , Signal Transduction/drug effects
12.
Sci Rep ; 9(1): 18970, 2019 12 12.
Article in English | MEDLINE | ID: mdl-31831780

ABSTRACT

Immunosuppression is critical for tumor growth and metastasis as well as obstacle to effective immunotherapy. Here, we demonstrate that host deficiency in caveolin-2, a member of caveolin protein family, increases M1-polarized tumor-associated macrophage (TAM) and CD8 T cell infiltration into subcutaneously implanted murine lung carcinoma tumors. Importantly, increase in M1 TAM-specific markers and cytokines occurs prior to increased numbers of tumor-infiltrating CD8 T cells and tumor regression in caveolin-2 deficient mice, suggesting that an early increase in M1 TAMs is a novel mechanism, via which host deficiency in caveolin-2 inhibits tumor growth. Consistent with the latter, transfer and co-injection of caveolin-2 deficient bone marrow (origin of TAMs) suppresses tumor growth and increases numbers of M1-polarized TAMs in wild type mice. Collectively, our data suggest that lung cancer cells use caveolin-2 expressed in bone marrow-derived cell types including TAMs to promote tumor growth via suppressing the anti-tumor immune response and that caveolin-2 could be a potential target for cancer immunotherapy.


Subject(s)
CD8-Positive T-Lymphocytes/immunology , Caveolin 2/deficiency , Immunity, Cellular , Lung Neoplasms/immunology , Macrophages/immunology , Neoplasm Proteins/deficiency , Neoplasms, Experimental/immunology , Animals , CD8-Positive T-Lymphocytes/pathology , Caveolin 2/immunology , Cell Line, Tumor , Immunotherapy , Lung Neoplasms/genetics , Lung Neoplasms/pathology , Lung Neoplasms/therapy , Macrophages/pathology , Mice , Mice, Knockout , Neoplasm Proteins/immunology , Neoplasms, Experimental/genetics , Neoplasms, Experimental/pathology , Neoplasms, Experimental/therapy
13.
J Vis Exp ; (151)2019 09 12.
Article in English | MEDLINE | ID: mdl-31566616

ABSTRACT

The absence of a clinically relevant animal model addressing the typical immune characteristics of hepatocellular cancer (HCC) has significantly impeded elucidation of the underlying mechanisms and development of innovative immunotherapeutic strategies. To develop an ideal animal model recapitulating human HCC, immunocompetent male C57BL/6J mice first receive a carbon tetrachloride (CCl4) injection to induce liver fibrosis, then receive histologically-normal oncogenic hepatocytes from young male SV40 T antigen (TAg)-transgenic mice (MTD2) by intra-splenic (ISPL) inoculation. Androgen generated in recipient male mice at puberty initiates TAg expression under control of a liver-specific promoter. As a result, the transferred hepatocytes become cancer cells and form tumor masses in the setting of liver fibrosis/cirrhosis. This novel model mimics human HCC initiation and progression in the context of liver fibrosis/cirrhosis and reflects the most typical features of human HCC including immune dysfunction.


Subject(s)
Carcinoma, Hepatocellular/pathology , Hepatitis, Animal/pathology , Hepatocytes/pathology , Liver Cirrhosis/pathology , Liver Neoplasms/pathology , Oncogenes , Animals , Disease Models, Animal , Disease Progression , Humans , Male , Mice , Mice, Inbred C57BL , Mice, Transgenic
14.
Cancer Lett ; 454: 204-214, 2019 07 10.
Article in English | MEDLINE | ID: mdl-31004701

ABSTRACT

Liver-intestine cadherin (CDH17) has been known to function as a tumor stimulator and diagnostic marker for almost two decades. However, its function in highly malignant pancreatic cancer (PC) has yet to be elucidated. Using different strategies including siRNA, shRNA, and CRISPR technology, we successfully induced knockdown and knockout of CDH17 in Panc02-H7 cells and established the corresponding stable cell lines. With these cells, we demonstrated that loss of CDH17 function not only suppressed Panc02-H7 cell growth in vitro but also significantly slowed orthotopic tumor growth in vivo, resulting in the significant life extension. In vitro studies demonstrated that impairing CDH17 inhibited cell proliferation, colony formation, and motility by mechanistically modulating pro- and anti-apoptosis events in PC cells, as CDH17 suppression obviously increased expression of Bad, cytochrome C, cleaved caspase 3, and cleaved PARP, and reduced expression of Bcl-2, Survivin, and pAkt. In vivo studies showed CDH17 knockout resulted in apoptotic PC tumor death through activating caspase-3 activity. Taken together, CDH17 functions as an oncogenic molecule critical to PC growth by regulating tumor apoptosis signaling pathways and CDH17 could be targeted to develop an anti-PC therapeutic approach.


Subject(s)
Cadherins/genetics , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/pathology , Animals , Apoptosis/physiology , Cadherins/biosynthesis , Cell Line, Tumor , Cell Movement/genetics , Gene Knockdown Techniques , Gene Knockout Techniques , HEK293 Cells , Humans , Male , Mice , Mice, Inbred C57BL , Pancreatic Neoplasms/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Proto-Oncogene Proteins c-bcl-2/metabolism , RNA, Small Interfering/administration & dosage , RNA, Small Interfering/genetics , Signal Transduction , Transfection
15.
J Immunol Res Ther ; 3(1): 115-123, 2018.
Article in English | MEDLINE | ID: mdl-30123861

ABSTRACT

Sorafenib and sunitinib are multiple tyrosine kinase inhibitors. Both of them have been approved by the US FDA in the treatment of patients with malignancies. In order to develop an effective and clinically useful chemoimmunotherapy modality against hepatocellular cancer (HCC), we investigate their tumoricidal and immune modulatory effect in the setting of HCC. In vitro experiments suggested that sunitinib and sorafenib both induced HCC cell apoptosis at an equivalent level, but stronger suppressive function to cell proliferation was detected in sorafenib. Correspondingly, treatment of tumor-bearing mice with sorafenib led to the suppression of tumor growth to a larger extent than sunitinib. Flow cytometry showed that treatment with sunitinib, not sorafenib, significantly reduced the frequency of regulatory T cells (Tregs) and myeloid-derived suppressive cells (MDSCs) in tumor-bearing mice; and allowed splenic lymphocytes to produce equivalent levels of IFN-γ and TNF-α in response to vaccination as that in wild type mice. This activation was not detected in control and sorafenib-treated tumor mice. In addition, treatment of tumor-bearing mice with sunitinib followed by adoptive transfer of tumor antigen-specific CD8+ T cells and immunization resulted in the additional suppression to tumor growth compared to sunitinib monotherapy. These results imply treatment with sunitinib, not sorafenib, is able to prevent tumor-induced immunotolerance and activate antitumorimmunity. Our data suggest that sunitinib may be a preferable chemotherapeutic agent to use in combination with immunotherapy for the treatment of HCC.

16.
Gastroenterology ; 154(4): 1024-1036.e9, 2018 03.
Article in English | MEDLINE | ID: mdl-29408569

ABSTRACT

BACKGROUND & AIMS: Ceramide, a sphingolipid metabolite, affects T-cell signaling, induces apoptosis of cancer cells, and slows tumor growth in mice. However, it has not been used as a chemotherapeutic agent because of its cell impermeability and precipitation in aqueous solution. We developed a nanoliposome-loaded C6-ceremide (LipC6) to overcome this limitation and investigated its effects in mice with liver tumors. METHODS: Immune competent C57BL/6 mice received intraperitoneal injections of carbon tetrachloride and intra-splenic injections of oncogenic hepatocytes. As a result, tumors resembling human hepatocellular carcinomas developed in a fibrotic liver setting. After tumors formed, mice were given an injection of LipC6 or vehicle via tail vein every other day for 2 weeks. This was followed by administration, also via tail vein, of tumor antigen-specific (TAS) CD8+ T cells isolated from the spleens of line 416 mice, and subsequent immunization by intraperitoneal injection of tumor antigen-expressing B6/WT-19 cells. Tumor growth was monitored with magnetic resonance imaging. Tumor apoptosis, proliferation, and AKT expression were analyzed using immunohistochemistry and immunoblots. Cytokine production, phenotype, and function of TAS CD8+ T cells and tumor-associated macrophages (TAMs) were studied with flow cytometry, real-time polymerase chain reaction (PCR), and ELISA. Reactive oxygen species (ROS) in TAMs and bone marrow-derived macrophages, induced by colony stimulating factor 2 (GMCSF or CSF2) or colony stimulating factor 1 (MCSF or CSF1), were detected using a luminescent assay. RESULTS: Injection of LipC6 slowed tumor growth by reducing tumor cell proliferation and phosphorylation of AKT, and increasing tumor cell apoptosis, compared with vehicle. Tumors grew more slowly in mice given the combination of LipC6 injection and TAS CD8+ T cells followed by immunization compared with mice given vehicle, LipC6, the T cells, or immunization alone. LipC6 injection also reduced numbers of TAMs and their production of ROS. LipC6 induced TAMs to differentiate into an M1 phenotype, which reduced immune suppression and increased activity of CD8+ T cells. These results were validated by experiments with bone marrow-derived macrophages induced by GMCSF or MCSF. CONCLUSIONS: In mice with liver tumors, injection of LipC6 reduces the number of TAMs and the ability of TAMs to suppress the anti-tumor immune response. LipC6 also increases the anti-tumor effects of TAS CD8+ T cells. LipC6 might therefore increase the efficacy of immune therapy in patients with hepatocellular carcinoma.


Subject(s)
Antineoplastic Agents/pharmacology , Carcinoma, Hepatocellular/drug therapy , Ceramides/pharmacology , Liver Neoplasms/drug therapy , Tumor Burden/drug effects , Animals , Antigens, Polyomavirus Transforming/genetics , Apoptosis/drug effects , CD8-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/metabolism , CD8-Positive T-Lymphocytes/transplantation , Carcinoma, Hepatocellular/immunology , Carcinoma, Hepatocellular/metabolism , Carcinoma, Hepatocellular/pathology , Cell Line, Transformed , Cell Proliferation/drug effects , Cytokines/metabolism , Immunotherapy, Adoptive/methods , Liposomes , Liver Neoplasms/immunology , Liver Neoplasms/metabolism , Liver Neoplasms/pathology , Macrophages/drug effects , Macrophages/immunology , Macrophages/metabolism , Magnetic Resonance Imaging , Male , Mice, Inbred C57BL , Mice, Transgenic , Nanoparticles , Promoter Regions, Genetic , Proteins/genetics , Proto-Oncogene Proteins c-akt/metabolism , Reactive Oxygen Species/metabolism , Signal Transduction/drug effects , Time Factors , Tumor Escape/drug effects , Tumor Microenvironment
17.
Oncotarget ; 8(52): 90215-90224, 2017 Oct 27.
Article in English | MEDLINE | ID: mdl-29163822

ABSTRACT

Monoclonal antibodies targeting PD-1/PD-L1 signaling pathway have achieved unprecedented success in cancer treatment over the last few years. Atezolizumab is the first PD-L1 monoclonal antibody approved by US FDA for cancer therapy; however the molecular basis of atezolizumab in blocking PD-1/PD-L1 interaction is not fully understood. Here we have solved the crystal structure of PD-L1/atezolizumab complex at 2.9 angstrom resolution. The structure shows that atezolizumab binds the front beta-sheet of PD-L1 through three CDR loops from the heavy chain and one CDR loop from the light chain. The binding involves extensive hydrogen-bonding and hydrophobic interactions. Notably there are multiple aromatic residues from the CDR loops forming Pi-Pi stacking or cation-Pi interactions within the center of the binding interface and the buried surface area is more than 2000 Å2, which is the largest amongst all the known PD-L1/antibody structures. Mutagenesis study revealed that two hot-spot residues (E58, R113) of PD-L1 contribute significantly to the binding of atezolizumab. The structure also shows that atezolizumab binds PD-L1 with a distinct heavy and light chain orientation and it blocks PD-1/PD-L1 interaction through competing with PD-1 for the same PD-L1 surface area. Taken together, the complex structure of PD-L1/atezolizumab solved here revealed the molecular mechanism of atezolizumab in immunotherapy and provides basis for future monoclonal antibody optimization and rational design of small chemical compounds targeting PD-L1 surface.

18.
J Hepatol ; 66(1): 75-85, 2017 01.
Article in English | MEDLINE | ID: mdl-27520877

ABSTRACT

BACKGROUND & AIMS: We have established a clinically relevant animal model of hepatocellular cancer (HCC) in immune competent mice to elucidate the complex dialog between host immunity and tumors during HCC initiation and progression. Mechanistic findings have been leveraged to develop a clinically feasible anti-tumor chemoimmunotherapeutic strategy. METHODS: Intraperitoneal injection of carbon tetrachloride and intrasplenic inoculation of oncogenic hepatocytes were combined to induce progressive HCCs in fibrotic livers of immunocompetent mice. Immunization and adoptive cell transfer (ACT) were used to dissect the tumor antigen-specific immune response. The ability of the tyrosine kinase inhibitor sunitinib to enhance immunotherapy in the setting of HCC was evaluated. RESULTS: This new mouse model mimics human HCC and reflects its typical features. Tumor-antigen-specific CD8+ T cells maintained a naïve phenotype and remained responsive during early-stage tumor progression. Late tumor progression produced circulating tumor cells, tumor migration into draining lymph nodes, and profound exhaustion of tumor-antigen-specific CD8+ T cells associated with accumulation of programmed cell death protein 1 (PD-1)hi CD8+ T cells and regulatory T cells (Tregs). Sunitinib-mediated tumoricidal effect and Treg suppression synergized with antibody-mediated blockade of PD-1 to powerfully suppress tumor growth and activate anti-tumor immunity. CONCLUSION: Treg accumulation and upregulation of PD-1 provide two independent mechanisms to induce profound immune tolerance in HCC. Chemoimmunotherapy using Food and Drug Administration-approved sunitinib with anti-PD-1 antibodies achieved significant tumor control, supporting translation of this approach for the treatment of HCC patients. LAY SUMMARY: In the current study, we have established a clinically relevant mouse model which mimics human liver cancer. Using this unique model, we studied the response of the immune system to this aggressive cancer. Findings from this trial have led to the development of an innovative and clinically feasible chemoimmunotherapeutic strategy.


Subject(s)
Carcinoma, Hepatocellular , Immunotherapy/methods , Indoles/pharmacology , Liver Neoplasms , Pyrroles/pharmacology , Adoptive Transfer , Animals , CD8-Positive T-Lymphocytes/immunology , Carcinoma, Hepatocellular/drug therapy , Carcinoma, Hepatocellular/immunology , Carcinoma, Hepatocellular/pathology , Cytotoxicity, Immunologic/physiology , Disease Models, Animal , Enzyme Inhibitors/pharmacology , Histocompatibility Antigens Class II/immunology , Immune Tolerance , Liver Neoplasms/drug therapy , Liver Neoplasms/immunology , Liver Neoplasms/pathology , Mice , Neoplasm Staging , Programmed Cell Death 1 Receptor/metabolism , Sunitinib , T-Lymphocytes, Regulatory/immunology
19.
PLoS One ; 11(11): e0165891, 2016.
Article in English | MEDLINE | ID: mdl-27806108

ABSTRACT

Sex differences in spatial memory have long been observed in humans, non-human primates and rodents, but the underlying cellular and molecular mechanisms responsible for these differences remain obscure. In the present study we found that adolescent male rats outperformed female rats in 7 d and 28 d retention probes, but not in learning trials and immediate probes, in the Morris water maze task. Male rats also had larger long-term potentiation (LTP) at hippocampal temproammonic-CA1 (TA-CA1) synapses, which have been implicated to play a key role in place field and memory consolidation, when protocols designed to elicit late-stage LTP (LLTP) were used. Interestingly, the ratio of evoked AMPA/NMDA currents was found to be smaller at TA-CA1 synapses in male rats compared to female rats. Protein biotinylation experiments showed that male rats expressed more surface GluN1 receptors in hippocampal CA1 stratum lacunosum-moleculare (SLM) than female rats, although GluA1 expression was also slightly higher in male rats. Taken together, our results suggest that differences in the expression of AMPA and NMDA receptors may affect LTP expression at TA-CA1 synapses in adolescent male and female rats, and thus possibly contribute to the observed sex difference in spatial memory.


Subject(s)
CA1 Region, Hippocampal/physiology , Long-Term Potentiation , Memory Consolidation/physiology , Receptors, AMPA/metabolism , Receptors, N-Methyl-D-Aspartate/metabolism , Animals , Female , Male , Maze Learning , Rats , Rats, Sprague-Dawley , Sex Characteristics
20.
J Clin Cell Immunol ; 7(4)2016 Aug.
Article in English | MEDLINE | ID: mdl-27656328

ABSTRACT

Manipulation of immune system toward the rejection of established cancers has become the standard of care in some patients. Here we propose the development of an in situ autologous cancer vaccine, inCVAX, for the treatment of hepatocellular cancer (HCC). inCVAX is based on the induction of local immunogenic cancer cell death combined with local dendritic cell stimulation by intratumoral injection of the immune-activator N-dihydro-galacto-chitosan (GC). In a first set of experiments, cellular and molecular studies were performed to investigate the effect of inCVAX on immune activation in a murine model of HCC that we previously developed. Once large tumors were formed in mice, the tumor is surgically exposed and a laser fiber was inserted into the center of an individual tumor mass. Using a 10 mm diffuser tip, laser irradiation of 1.5 W was applied to heat the tumor at different durations (6-10 min) to assess tolerability of photothermal application at different temperatures. The laser application was followed by immediate injection of GC, and each mouse received one laser treatment and one GC injection. ELISA was used to assess the level of cytokines; immunohistochemical staining was conducted to analyze the effect of inCVAX on immune cell tumor-filtration and expression of tumor-specific antigens (TSAs) and tumor-associated antigens (TAAs). Results indicate that survival correlated to thermal exposure. At lower temperatures the photothermal effect was sufficient to induce tumor necrosis, but without obvious complication to the mice, although at these temperatures the treatment didn't alter the level of TSAs and TAAs, so further optimization is suggested. Nevertheless, in response to the inCVAX treatment, cytotoxic cytokine IFN-γ was significantly increased, but suppressive cytokine TGF-ß was dramatically reduced. Furthermore, inCVAX prompted tumor infiltration of CD3+, CD4+, and CD8+ T cells; but modulated macrophage subsets differently. In conclusion, while the protocol needs further optimization, it would appear that inCVAX for the treatment of HCC activates an immune response in tumor-bearing mice, which in turn may have potential for the treatment of HCC.

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