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1.
Immunotherapy ; 14(15): 1263-1277, 2022 10.
Article in English | MEDLINE | ID: mdl-36004447

ABSTRACT

The disease relevance of novel therapeutic agent T11TS, established first by the authors' group, was shown to ameliorate experimental glioma through multimodal mechanistic activities. T11TS reverses immunosuppression in glioma, causing profound effects on immune potentiation via peripheral, intracranial and hematopoietic cells. T-cell signaling in glioma is reversed by T11TS, modulating cytokine levels and favoring apoptotic killing of glioma cells. T11TS arrests the glioma cell cycle at the G1 phase via activation of p21. VEGF downregulation hypophosphorylates the Akt pathway. T11TS hinders endothelial cell progression and metastasis by arresting matrix degradation, inhibiting the Ras-Raf and Akt-PTEN pathways and initiating inflammatory changes, causing apoptosis. T11TS is effective against in vitro human glioma. Toxicity studies demonstrate that T11TS is nontoxic. The authors' study promise translational research with T11TS.


Glioma is a fatal brain tumor, and conventional treatments with surgery, radiotherapy, and chemotherapy often cause cancer recurrence. Therefore, newer strategies of treatment are being developed. In the authors' laboratory, a novel molecular approach with the biomolecule T11TS has been successfully applied in the eradication of glioma in an experimental rat model and on human samples. T11TS ameliorates glioma by various means, including immune augmentation and cytokine modulation; causes glioma cell death (apoptotic); halts the glioma cell cycle; and retards glioma blood vessel growth (antiangiogenic). T11TS is nontoxic. The author's study points to novel glioma therapy.


Subject(s)
Antineoplastic Agents , Brain Neoplasms , Glioma , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Apoptosis , Brain Neoplasms/drug therapy , Cytokines/therapeutic use , Glioma/drug therapy , Humans , Proto-Oncogene Proteins c-akt/metabolism , Vascular Endothelial Growth Factor A
2.
Cancer Invest ; 39(10): 854-870, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34569407

ABSTRACT

The novel anti-neoplastic glycopeptide T11TS retards glioma both in in-vitro clinical samples and in-vivo models. This study investigates the correlation between altering the glioma microenvironment with glioma arrest and death. Flow cytometry, immunoblotting, ELISA, and co-immunoprecipitation were employed to investigate glioma cell arrest and death. Results include a decline in phosphorylation of Akt and attenuation of p21 phosphorylation (Thr145,Ser146) and disassociation of p-Akt-Mdm2 and p-Akt-BAD facilitating death by Akt>BAD. T11TS influence phosphorylation patterns in two focal axes Akt>p21 and Akt>Mdm2>p53. The current article provides crucial insight in deciphering the mechanism of T11TS induced glioma cell arrest and death.


Subject(s)
Brain Neoplasms/drug therapy , CD58 Antigens/pharmacology , Glioma/drug therapy , Proto-Oncogene Proteins c-akt/metabolism , Animals , Brain Neoplasms/metabolism , Brain Neoplasms/pathology , CD58 Antigens/therapeutic use , Cell Cycle Checkpoints/drug effects , Cyclin-Dependent Kinase Inhibitor p21/metabolism , Female , Glioma/metabolism , Glioma/pathology , Male , PTEN Phosphohydrolase/analysis , Phosphorylation , Proto-Oncogene Proteins c-mdm2/analysis , Rats , Rats, Wistar , Tumor Microenvironment , Tumor Suppressor Protein p53/analysis , bcl-Associated Death Protein/metabolism
3.
Arterioscler Thromb Vasc Biol ; 40(9): 2244-2264, 2020 09.
Article in English | MEDLINE | ID: mdl-32640900

ABSTRACT

OBJECTIVE: Nanog is expressed in adult endothelial cells (ECs) at a low-level, however, its functional significance is not known. The goal of our study was to elucidate the role of Nanog in adult ECs using a genetically engineered mouse model system. Approach and Results: Biochemical analyses showed that Nanog is expressed in both adult human and mouse tissues. Primary ECs isolated from adult mice showed detectable levels of Nanog, Tert (telomerase reverse transcriptase), and eNos (endothelial nitric oxide synthase). Wnt3a (Wnt family member 3A) increased the expression of Nanog and hTERT (human telomerase reverse transcriptase) in ECs and increased telomerase activity in these cells. In a chromatin immunoprecipitation experiment, Nanog directly bound to the hTERT and eNOS promoter/enhancer DNA elements, thereby regulating their transcription. Administration of low-dose tamoxifen to ROSAmT/mG::Nanogfl/+::Cdh5CreERT2 mice induced deletion of a single Nanog allele, simultaneously labeling ECs with green fluorescent protein and resulting in decreased Tert and eNos levels. Histological and morphometric analyses of heart tissue sections prepared from these mice revealed cell death, microvascular rarefaction, and increased fibrosis in cardiac vessels. Accordingly, EC-specific Nanog-haploinsufficiency resulted in impaired EC homeostasis and angiogenesis. Conversely, re-expression of cDNA encoding the hTERT in Nanog-depleted ECs, in part, restored the effect of loss of Nanog. CONCLUSIONS: We showed that low-level Nanog expression is required for normal EC homeostasis and angiogenesis in adulthood.


Subject(s)
Cell Proliferation , Cellular Senescence , Coronary Vessels/metabolism , Endothelial Cells/metabolism , Endothelium, Vascular/metabolism , Nanog Homeobox Protein/metabolism , Animals , Apoptosis , Cell Proliferation/drug effects , Cells, Cultured , Cellular Senescence/drug effects , Coronary Vessels/drug effects , Coronary Vessels/pathology , Endothelial Cells/drug effects , Endothelial Cells/pathology , Endothelium, Vascular/drug effects , Endothelium, Vascular/pathology , Female , Fibrosis , Human Umbilical Vein Endothelial Cells/metabolism , Humans , Male , Mice, Inbred C57BL , Mice, Knockout , Nanog Homeobox Protein/deficiency , Nanog Homeobox Protein/genetics , Neovascularization, Physiologic , Nitric Oxide Synthase Type III/genetics , Nitric Oxide Synthase Type III/metabolism , Telomerase/genetics , Telomerase/metabolism , Transcriptional Activation , Wnt Signaling Pathway , Wnt3A Protein/pharmacology
4.
Mol Immunol ; 122: 207-221, 2020 May 07.
Article in English | MEDLINE | ID: mdl-32388483

ABSTRACT

Cryptococcus neoformans infects and disseminates in hosts with diminished T cell responses. The immunomodulator T11TS (T11 target structure) had profound potential in glioma as well as C. neoformans infected model for disease amelioration. It is been established by our group that T11TS potentiates Calcineurin-NFAT pathway in T cells of C. neoformans infected rats. We investigated the upstream Immunological Synapse (IS) molecules that are vital for the foundation of initial signals for downstream signaling, differentiation and proliferation in T cells. Improved RANTES level in the T11TS treated groups suggests potential recruitment of T cells. Down-regulation of TCRαß, CD3ζ, CD2, CD45 and CD28 molecules by cryptococcus were boosted after T11TS therapy. Heightened expression of inhibitory molecule CTLA-4 in cryptococcosis was dampened by T11TS. The decline of MHC I, MHC II and CD80 expression on macrophages by C. neoformans were enhanced by T11TS. The dampening of positive regulators and upsurge of negative regulators of the IS during cryptococcosis was reversed with T11TS therapy resulting in enhanced clearance of fungus from the lungs as envisaged by our histological studies. This preclinical study with T11TS opens a new prospect for potential immunotherapeutic intervention against the devastating C. neoformans infection with positive aspect for the long-term solution and a safer immunotherapeutic regimen.

5.
Scand J Immunol ; 89(2): e12733, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30450625

ABSTRACT

Cryptococcus neoformans, the encapsulated yeast acquired through inhalation, remains localized in lungs, but harbours the CNS in immunocompromised individuals. Several treatment regimes have failed combating this disease totally, but long-term usage of drugs leads to organ damage. As T11-target structure (T11TS) has documented profound immune potentiation, we aimed to investigate the role of microglia, pivotal immune cells of brain in ameliorating cryptococcosis, with T11TS immunotherapy. Murine model with C neoformans infection was prepared by intraperitoneal injection and the brains of rats examined 7 days post-infections for histopathology by PAS and Alcian blue staining corroborated with organ fungal burden evidencing restorative T11TS action on Cryptococcal meningitis. Immunotherapy with three doses of T11TS, a CD2 ligand, in C neoformans infected rats, upregulates toll-like receptors 2, -4 and -9 of microglia, indicating increased phagocytosis of the fungus. Flowcytometric analysis revealed increased numbers of T11TS treated brain infiltrating CD4+ and CD8+ T-lymphocytes along with increased MHC I and MHC II on microglia, activating the infiltrating lymphocytes aiding the killing mechanism. Present study also indicated that T11TS increased production of Th1 inflammatory cytokines conducive to fungal elimination while the inhibitory Th2 cytokines were dampened. This preclinical study is first of its kind to show that T11TS effected profound immune stimulation of microglial activity of C neoformans infected rats eradicating residual fungal burden from the brain and can be a useful therapeutic strategy in fighting against this deadly disease.


Subject(s)
Brain/drug effects , CD58 Antigens/therapeutic use , Cryptococcus neoformans/physiology , Immunologic Factors/therapeutic use , Immunotherapy/methods , Meningitis, Cryptococcal/therapy , Microglia/immunology , Animals , Brain/immunology , Brain/microbiology , Cattle , Cells, Cultured , Cytokines/metabolism , Disease Models, Animal , Humans , Immunity, Innate/drug effects , Inflammation Mediators/metabolism , Male , Meningitis, Cryptococcal/immunology , Microglia/pathology , Rats , Rats, Wistar , T-Lymphocytes/immunology , Toll-Like Receptors/metabolism
6.
J Cell Physiol ; 233(2): 759-770, 2018 Feb.
Article in English | MEDLINE | ID: mdl-28608562

ABSTRACT

Malignant glioma is the most fatal of astrocytic lineage tumors despite therapeutic advances. Onset and progression of gliomas is accompanied by severe debilitation of T-cell defense and T-cell survival. One of the chief contributors to T-cell survival downstream of activation is the PI3K-AKT pathway. Our prior studies showed that the novel immunotherapeutic molecule T11-target structure (T11TS) blocks T-cell apoptosis in glioma. We also showed activation of immunological synapse components and calcineurin-NFAT pathway following T11TS immunotherapy of glioma-bearing rats. This lead to investigations whether such T-cell activation upon T11TS therapy translates into activation of downstream PI3K/AKT signals which may be related to observed blockade of T-cell apoptosis. For the purpose, we assessed by flowcytometry and immunoblotting, expressions of PI3K, PDK1, AKT, p-AKT, and PTEN in splenic T-cells of normal, experimentally-induced glioma-bearing rats and glioma-bearing rats receiving first, second and third doses of T11TS. We also determined comparative nuclear translocation of NF-κB across groups. We found significant increases in T-cell expressions of PDK1, PI3K, and p-AKT in T11TS-treated animal groups compared to sharp downregulations in glioma. AKT levels remained unchanged across groups. PTEN levels declined sharply after T11TS immunotherapy. T11TS also caused enhanced NF-κB translocation to the T-cell nucleus compared to glioma group. Results showed heightened activation of the PI3K-AKT pathway in glioma-bearing rats following T11TS immunotherapy. These results illustrate the novel role of T11TS immunotherapy in ameliorating the PI3K pathway in T-cells in glioma-bearing animals to enhance T-cell survival, according greater defense against glioma. The study thus has far-reaching clinical outcomes.


Subject(s)
Antineoplastic Agents/pharmacology , Brain Neoplasms/drug therapy , CD58 Antigens/pharmacology , Glioma/drug therapy , Immunotherapy/methods , Phosphatidylinositol 3-Kinase/metabolism , Proto-Oncogene Proteins c-akt/metabolism , T-Lymphocytes/drug effects , Tumor Escape/drug effects , 3-Phosphoinositide-Dependent Protein Kinases/metabolism , Active Transport, Cell Nucleus , Animals , Brain Neoplasms/enzymology , Brain Neoplasms/immunology , Brain Neoplasms/pathology , CD28 Antigens/immunology , CD28 Antigens/metabolism , Cell Survival , Ethylnitrosourea , Female , Glioma/enzymology , Glioma/immunology , Glioma/pathology , Male , NF-kappa B/metabolism , PTEN Phosphohydrolase/metabolism , Phosphorylation , Rats , Signal Transduction/drug effects , T-Lymphocytes/enzymology , T-Lymphocytes/immunology
7.
J Biol Chem ; 292(50): 20785-20798, 2017 12 15.
Article in English | MEDLINE | ID: mdl-29070680

ABSTRACT

A key feature of acute myocardial infarction (AMI) is an alteration in cardiac architecture. Signaling events that result in the inhibition of glycogen synthase kinase-3 (GSK-3)ß represent an adaptive response that might limit the extent of adverse remodeling in the aftermath of AMI. Here, we report that an allosteric inhibitor of GSK-3ß, 4-benzyl-2-(naphthalene-1-yl)-1,2,4-thiadiazolidine-3,5-dione (NP12), lessens the magnitude of adverse myocardial remodeling and promotes angiogenesis. Male and female mice 8-10 weeks old were grouped (six animals in each group) into sham surgery (sham group), left anterior descending (LAD) ligation of the coronary artery followed by intramyocardial PBS injections (control group), and LAD ligation followed by NP12 administration (NP12 group). After 7 and 14 days, the extents of fibrosis and integrity of blood vessels were determined. Intramyocardial administration of NP12 increased phosphorylation of GSK-3ß, reduced fibrosis, and restored diastolic function in the mice that had experienced an AMI. Morphometric analyses revealed increased CD31+ and Ki67+ vascular structures and decreased apoptosis in these mice. NP12 administration mediated proliferation of reparative cells in the AMI hearts. In a time-course analysis, Wnt3a and NP12 stabilized ß-catenin and increased expression of both Nanog and VEGFR2. Moreover, NP12 increased the expression of ß-catenin and Nanog in myocardium from AMI mice. Finally, loss- and gain-of-function experiments indicated that the NP12-mediated benefit is, in part, Nanog-specific. These findings indicate that NP12 reduces fibrosis, reestablishes coronary blood flow, and improves ventricular function following an AMI. We conclude that NP12 might be useful for limiting ventricular remodeling after an AMI.


Subject(s)
Angiogenesis Inducing Agents/therapeutic use , Atrial Remodeling/drug effects , Disease Models, Animal , Glycogen Synthase Kinase 3/antagonists & inhibitors , Myocardial Infarction/drug therapy , Protein Kinase Inhibitors/therapeutic use , Thiadiazoles/therapeutic use , Allosteric Regulation/drug effects , Angiogenesis Inducing Agents/pharmacology , Animals , Aorta/drug effects , Aorta/metabolism , Aorta/pathology , Aorta/surgery , Apoptosis/drug effects , Coronary Vessels/drug effects , Coronary Vessels/pathology , Female , Glycogen Synthase Kinase 3/metabolism , Heart Ventricles/drug effects , Heart Ventricles/metabolism , Heart Ventricles/pathology , Heart Ventricles/physiopathology , In Vitro Techniques , Ligation , Male , Mice, Inbred BALB C , Mice, Inbred C57BL , Myocardial Infarction/metabolism , Myocardial Infarction/pathology , Myocardial Infarction/physiopathology , Neovascularization, Physiologic/drug effects , Phosphorylation/drug effects , Protein Kinase Inhibitors/pharmacology , Protein Processing, Post-Translational/drug effects , Thiadiazoles/pharmacology
8.
Front Microbiol ; 8: 706, 2017.
Article in English | MEDLINE | ID: mdl-28484443

ABSTRACT

HIV-1 evades host defense through mutations and recombination events, generating numerous variants in an infected patient. These variants with an undiminished virulence can multiply rapidly in order to progress to AIDS. One of the targets to intervene in HIV-1 replication is the trans-activator of transcription (Tat), a major regulatory protein that transactivates the long terminal repeat promoter through its interaction with trans-activation response (TAR) RNA. In this study, HIV-1 infected patients (n = 120) from North India revealed Ser46Phe (20%) and Ser61Arg (2%) mutations in the Tat variants with a strong interaction toward TAR leading to enhanced transactivation activities. Molecular dynamics simulation data verified that the variants with this mutation had a higher binding affinity for TAR than both the wild-type Tat and other variants that lacked Ser46Phe and Ser61Arg. Other mutations in Tat conferred varying affinities for TAR interaction leading to differential transactivation abilities. This is the first report from North India with a clinical validation of CD4 counts to demonstrate the influence of Tat genetic variations affecting the stability of Tat and its interaction with TAR. This study highlights the co-evolution pattern of Tat and predominant nucleotides for Tat activity, facilitating the identification of genetic determinants for the attenuation of viral gene expression.

9.
J Cell Physiol ; 232(3): 526-539, 2017 Mar.
Article in English | MEDLINE | ID: mdl-27255231

ABSTRACT

Malignant glioma continues to be a clinical challenge with an urgent need for developing curative therapeutic intervention. Apoptosis induction in tumor-associated endothelial cells represent a central mechanism that counteracts angiogenesis in glioma and other solid tumors. We previously demonstrated that intraperitoneal administration of sheep erythrocyte membrane glycopeptide T11-target structure (T11TS) in rodent glioma model inhibits PI3K/Akt pathway and Raf/MEK/ERK signaling in glioma-associated brain endothelial cells. In the present study, we investigated whether T11TS treatment influence apoptosis signaling in vivo in glioma-associated brain endothelial cells. Annexin-V/PI staining showed that T11TS treatment in glioma-induced rats increases apoptosis of glioma-associated endothelial cells within glioma milieu compared to brain endothelial cells in glioma induced and control groups. Flowcytometric JC-1 assay revealed that T11TS administration triggers loss of mitochondrial membrane potential in glioma-associated brain endothelial cells. Flowcytometry, immunoblotting, and in situ immunofluoresecnt imaging were employed to investigate the effect of T11TS on apoptotic regulatory proteins in brain endothelial cells. T11TS treatment-upmodulated expression of p53, Bax, Fas, FasL, and FADD in glioma associated endothelial cells and downregulated Bcl-2 protein. T11TS therapy induced cytochrome-c release into cytosol, activated caspase -9, 8, 3, and cleaved Bid in glioma associated brain endothelial cells. The study demonstrates that T11TS induces apoptosis in glioma-associated brain endothelial cells via p53 accumulation and activation of intrinsic as well as Fas-dependent extrinsic pathway. The pro-apoptotic action of T11TS on glioma-associated endothelial cells provides crucial insight into how T11TS exerts its anti-angiogenic function in glioma. J. Cell. Physiol. 232: 526-539, 2017. © 2016 Wiley Periodicals, Inc.


Subject(s)
Angiogenesis Inhibitors/therapeutic use , Apoptosis/drug effects , Brain Neoplasms/drug therapy , Endothelial Cells/pathology , Glioma/pathology , Glycopeptides/pharmacology , Glycopeptides/therapeutic use , Membrane Glycoproteins/pharmacology , Membrane Glycoproteins/therapeutic use , Neovascularization, Pathologic/drug therapy , Angiogenesis Inhibitors/pharmacology , Animals , BH3 Interacting Domain Death Agonist Protein/metabolism , Brain Neoplasms/pathology , Caspases/metabolism , Cytochromes c/metabolism , Cytosol/metabolism , Endothelial Cells/drug effects , Enzyme Activation , Fas Ligand Protein/metabolism , Fas-Associated Death Domain Protein/metabolism , Female , Glycopeptides/administration & dosage , Male , Membrane Glycoproteins/administration & dosage , Membrane Potential, Mitochondrial/drug effects , Models, Biological , Neovascularization, Pathologic/pathology , Rats , Sheep , Tumor Suppressor Protein p53/metabolism , bcl-2-Associated X Protein/metabolism , fas Receptor/metabolism
10.
Int Immunopharmacol ; 30: 111-120, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26667977

ABSTRACT

Pollen grains are well established to be an important cause of respiratory allergy. Current pharmacologic therapies for allergic asthma do not cure the disease. Allergen specific immunotherapy is the only treatment method which re-directs the immune system away from allergic response leading to a long lasting effect. The mechanism by which immunotherapy achieves this goal is an area of active research world-wide. The present experimental study was designed to develop an experimental model of allergic lung inflammation based on a relevant human allergen, Alstonia scholaris pollen, and to establish the immunological and cellular features of specific allergen immunotherapy using this same pollen extract. Our results revealed that Alstonia scholaris pollen sensitization and challenge causes eosinophilic airway inflammation with mucin hypersecretion. This is associated with increased total IgE, increased expression of FcɛRI on lung mast cells and increased levels of IL-4, IL-5 & IL-13 as confirmed by ELISA, in-situ immunofluorescence and FACS assay. Allergen specific immunotherapy reduced airway inflammation and also decreased total IgE level, FcɛRI expression, IL-4, IL-5 & IL-13 levels. It was further noted that the reduction of these levels was more by intra-nasal route than by intra-peritoneal route. Thus we present a novel animal model of Alstonia scholaris pollen allergic disease and specific allergen immunotherapy which will pave the way towards the development of better treatment modalities.


Subject(s)
Allergens/immunology , Desensitization, Immunologic , Eosinophils/immunology , Mast Cells/immunology , Pneumonia/therapy , Pollen/immunology , Rhinitis, Allergic, Seasonal/therapy , Administration, Intranasal , Alstonia/immunology , Animals , Cells, Cultured , Cytokines/metabolism , Disease Models, Animal , Humans , Immunoglobulin E/blood , Mucinoses , Pneumonia/immunology , Rats , Rats, Wistar , Receptors, IgE/metabolism , Rhinitis, Allergic, Seasonal/immunology , Th2 Cells/immunology
11.
Sci Rep ; 5: 15438, 2015 Oct 23.
Article in English | MEDLINE | ID: mdl-26494109

ABSTRACT

UNLABELLED: HIV-1 is characterized by high genetic heterogeneity which is a challenge for developing therapeutics. Therefore, it is necessary to understand the extent of genetic variations that HIV is undergoing in North India. The objective of this study was to determine the role of genetic and functional role of Vif on APOBEC3G degradation. Vif is an accessory protein involved in counteracting APOBEC3/F proteins. Genetic analysis of Vif variants revealed that Vif C variants were closely related to South African Vif C whereas Vif B variants and Vif B/C showed distinct geographic locations. This is the first report to show the emergence of Vif B/C in our population. The functional domains, motifs and phosphorylation sites were well conserved. Vif C variants differed in APOBEC3G degradation from Vif B variants. Vif B/C revealed similar levels of APOBEC3G degradation to Vif C confirming the presence of genetic determinants in C-terminal region. High genetic diversity was observed in Vif variants which may cause the emergence of more complex and divergent strains. These results reveal the genetic determinants of Vif in mediating APOBEC3G degradation and highlight the genetic information for the development of anti-viral drugs against HIV. IMPORTANCE: Vif is an accessory HIV-1 protein which plays significant role in the degradation of human DNA-editing factor APOBEC3G, thereby impeding the antiretroviral activity of APOBEC3G. It is known that certain natural polymorphisms in Vif could degrade APOBEC3G relatively higher rate, suggesting its role in HIV-1 pathogenesis. This is the first report from North India showcasing genetic variations and novel polymorphisms in Vif gene. Subtype C is prevalent in India, but for the first time we observed putative B/C recombinants with a little high ability to degrade APOBEC3G indicating adaptation and evolving nature of virus in our population. Indian Vif C variants were able to degrade APOBEC3G well in comparison to Vif B variants. These genetic changes were most likely selected during adaptation of HIV to our population. These results elucidate that the genetic determinants of Vif and highlights the potential targets for therapeutics.


Subject(s)
Cytidine Deaminase/metabolism , Recombination, Genetic , vif Gene Products, Human Immunodeficiency Virus/physiology , APOBEC-3G Deaminase , Amino Acid Sequence , HIV-1/genetics , Humans , India , Molecular Sequence Data , Phylogeny , Proteolysis , Sequence Homology, Amino Acid , vif Gene Products, Human Immunodeficiency Virus/chemistry , vif Gene Products, Human Immunodeficiency Virus/genetics
12.
Mol Immunol ; 67(2 Pt B): 256-64, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26105805

ABSTRACT

Malignant glioma is the most lethal of a wide array of CNS neoplasms. Its onset and progression are markedly associated with profound immunosupression and paralysis of T-cell survival and proliferation. Myriad immunotherapeutic strategies are presently used to target such T-cell anomalies in glioma. Our recent work has highlighted use of the novel glycopeptide, the CD2 ligand, T11 target structure (T11TS) as an immunotherapeutic agent against experimentally induced glioma in rats. We have shown that T11TS causes multi-target modulation of key components of the T-cell - antigen presenting cell (APC) immunological synapse. This consequently triggers T-cell activation so as to reverse glioma-induced changes to physiological levels. T11TS administration also causes CD2 upregulation. Earlier we also found T11TS to cause enhanced proliferation of both CD4+ and CD8+ T-cells in glioma conditions. These findings led us to believe that downstream CD2-stimulated "alternative pathway" of calcineurin-NFAT could be a possible target for modulation by T11TS. In the present paper we thus show that immunotherapy with T11TS induces a multi-targeted approach towards activation of this "alternative pathway" of T-cell signaling providing an immunotherapeutic advantage against glioma. We show here that T11TS immunotherapy causes positive modulations of the CD2 pathway-associated proteins, viz., p59fyn, protein kinase C-θ (PKC-θ), calcineurin and nuclear factor for activation of T-cells (NFAT) and hint that this may accord greater survival and proliferation advantage to T-cells of the glioma-bearing animals for augmented defence against glioma. These findings help open a molecular immunotherapeutic door - one which is directed towards clinical studies for glioma-immunotherapy using T11TS.


Subject(s)
CD2 Antigens/metabolism , Calcineurin/metabolism , Glioma/therapy , Immunotherapy , NFATC Transcription Factors/metabolism , Signal Transduction , T-Lymphocytes/metabolism , Animals , Animals, Newborn , Brain Neoplasms/immunology , Brain Neoplasms/therapy , Cell Nucleus/metabolism , Flow Cytometry , Fluorescent Antibody Technique , Glioma/immunology , Isoenzymes/metabolism , Protein Kinase C/metabolism , Protein Kinase C-theta , Rats , Sheep , Spleen/cytology
13.
Exp Mol Pathol ; 98(3): 455-66, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25797371

ABSTRACT

Malignant gliomas represent one of the most aggressive and hypervascular primary brain tumors. Angiopoietin-1, the peptide growth factor activates endothelial Tie-2 receptor promoting vessel maturation and vascular stabilization steps of angiogenesis in glioma. Epidermal growth factor receptor (EGFR) and Tie-2 receptor on endothelial cells once activated transmits signals through downstream Raf/MEK/ERK pathway promoting endothelial cell proliferation and migration which are essential for angiogenesis induction. The in vivo effect of sheep erythrocyte membrane glycopeptide T11-target structure (T11TS) on angiopoietin-1/Tie-2 axis, EGFR signaling and Raf/MEK/ERK pathway in glioma associated endothelial cells has not been investigated previously. The present study performed with rodent glioma model aims to investigate the effect of T11TS treatment on angiopoietin-1/Tie-2 signaling, EGFR activity and Raf/MEK/ERK pathway in glioma associated endothelial cells within glioma milieu. T11TS administration in rodent glioma model inhibited angiopoietin-1 expression and attenuated Tie-2 expression and activation in glioma associated brain endothelial cells. T11TS treatment also downregulated total and phosphorylated EGFR expression in glioma associated endothelial cells. Additionally T11TS treatment inhibited Raf-1 expression, MEK-1 and ERK-1/2 expression and phosphorylation in glioma associated brain endothelial cells. Thus T11TS therapy remarkably inhibits endothelial angiopoietin-1/Tie-2 signaling associated with vessel maturation and simultaneously antagonizes endothelial cell proliferation signaling by blocking EGFR activation and components of Raf/MEK/ERK pathway. Collectively, the findings demonstrate a multi-targeted anti-angiogenic activity of T11TS which augments the potential for clinical translation of T11TS as an effective angiogenesis inhibitor for glioma treatment.


Subject(s)
Angiopoietin-1/metabolism , Brain Neoplasms/metabolism , CD2 Antigens/pharmacology , Endothelial Cells/metabolism , Glioma/metabolism , Neovascularization, Pathologic/metabolism , Receptor, TIE-2/metabolism , Animals , Brain/blood supply , Brain/metabolism , Brain Neoplasms/pathology , Endothelial Cells/drug effects , ErbB Receptors/metabolism , Female , Glioma/pathology , MAP Kinase Kinase 1/genetics , MAP Kinase Kinase 1/metabolism , MAP Kinase Kinase Kinases/genetics , MAP Kinase Kinase Kinases/metabolism , MAP Kinase Signaling System , Male , Mitogen-Activated Protein Kinase 1/genetics , Mitogen-Activated Protein Kinase 1/metabolism , Mitogen-Activated Protein Kinase 3/genetics , Mitogen-Activated Protein Kinase 3/metabolism , Neovascularization, Pathologic/pathology , Proto-Oncogene Proteins c-raf , Rats , Sheep
14.
Int Immunopharmacol ; 24(2): 198-207, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25528475

ABSTRACT

Glioma angiogenesis is the result of the interaction between cancer cells with endothelial cells, and the surrounding inflammatory cells. This interaction plays a crucial role in directing the neo-formation of blood vessels. In the carcinogenic milieu, inflammatory cytokines secreted from inflammatory cells affect endothelial cell functions that are indispensable for tumor growth and metastatic propagation. TNF-α, referred to as the 'inflammatory switch', has shown its potential as an inflammatory agent by activation of IL-8 and IL-6 through NF-κB mediated pathway. Therefore, inhibitors of angiogenesis appear to be promising therapeutic agents for advanced gliomas. Previous studies from our lab showed that T11TS, a membrane glycoprotein, has antiangiogenic and antineoplastic activities in experimental animals and human samples. The present experimental study was designed to evaluate the effect of T11TS therapy on inflammatory cytokine expression of TNF-α, IL-8, IL-6 and their downstream associated molecule NF-κB in vivo. Our results revealed that T11TS therapy induced downregulation of TNF-α, IL-8, IL-6, and NF-κB confirmed by FACS assay and ELISA. In situ-immunofluorescence results hint that T11TS has the efficacy to stop the inflammation related to angiogenesis. Moreover, upregulation of IL-4 and IL-10 in microglia after T11TS therapy helps in complete abrogation of glioma inflammation and angiogenesis. These effects might contribute to the antineoplastic activity of T11TS.


Subject(s)
Angiogenesis Inhibitors/administration & dosage , Antineoplastic Agents/administration & dosage , Brain Neoplasms/drug therapy , CD58 Antigens/administration & dosage , Endothelial Cells/drug effects , Glioma/drug therapy , Microglia/drug effects , Neovascularization, Pathologic/drug therapy , Animals , Apoptosis/drug effects , Brain Neoplasms/blood supply , Brain Neoplasms/immunology , CD58 Antigens/isolation & purification , Cytokines/metabolism , Endothelial Cells/immunology , Glioma/blood supply , Glioma/immunology , Humans , Inflammation Mediators/metabolism , Models, Animal , NF-kappa B/metabolism , Neovascularization, Pathologic/immunology , Rats , Rats, Inbred Strains , Signal Transduction/drug effects
15.
J Neurooncol ; 120(1): 19-31, 2014 Oct.
Article in English | MEDLINE | ID: mdl-25026997

ABSTRACT

T-cell-mediated immune responses are typically low in conditions of malignant glioma which has been known to cause marked immunesuppression and dysregulate major T-cell signaling molecules. Thus, T-cell-based immunotherapies are currently in vogue in the treatment of malignant glioma. The novel glycopeptide, T11TS/S-LFA-3/S-CD58 has previously been shown by our group to be highly efficacious in glioma abrogation in in vivo and in vitro conditions. This glycopeptide ligands to the costimulatory CD2 molecule on T-cells, causing profound immune stimulation leading to glioma abrogation, suggesting probable involvement of T11TS in modulation of the T-cell signaling pathway. The present study offers a multi-targeted approach towards repair of some of the key components of the immunological synapse at the T-cell-APC interface and is therefore the first of its kind to offer a holistic model of restoration of immunological synapse components so as to trigger T-cells towards activation against glioma. The study thus indicates that the totally dysregulated molecular events at the immunological synapse in glioma are restored back to normal levels with the administration of T11TS, which finally culminates in glioma abrogation. The present study thus delineates an important T-cell signaling approach whereby T11TS acts as an anti-neoplastic agent, thus helping to chart out newer avenues in the fight against gliomas.


Subject(s)
CD2 Antigens/metabolism , CD58 Antigens/metabolism , Glioma/prevention & control , Glycopeptides/therapeutic use , Immunological Synapses/immunology , T-Lymphocytes/immunology , Animals , Apoptosis , Brain Neoplasms/chemically induced , Brain Neoplasms/immunology , Brain Neoplasms/prevention & control , CD2 Antigens/immunology , CD58 Antigens/immunology , Ethylnitrosourea/toxicity , Female , Flow Cytometry , Fluorescent Antibody Technique , Glioma/chemically induced , Glioma/immunology , Lymphocyte Activation , Male , Mice , Mutagens/toxicity , Signal Transduction , T-Lymphocytes/metabolism , T-Lymphocytes/pathology
16.
Tumour Biol ; 35(3): 2231-46, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24242015

ABSTRACT

During glioma development, angiogenesis plays a crucial role in growth and vascularization of primary brain tumors. T11 target structure (T11TS), a bioactive molecule, has been documented as an anti-neoplastic agent in glioma-induced rats and also in human glioma in vitro. This novel molecule induces apoptosis of tumor cells by way of immune potentiation and impairs the glioma cell cycle, but its role in glioma angiogenesis has not been worked out in detail. Matrix metalloproteinases (MMPs) are enzymes promoting tumor angiogenesis by enzymatically remodeling the extracellular matrix and altering surface protein expression such as integrin αv and the matrix-bound proteins like TGF-ß1. The present study was formulated to assess the efficacy of T11TS in the modulations of MMP-2 and -9 and their endogenous inhibitors (TIMP-1 and TIMP-2) as well as modulations of integrin αv and TGF-ß1 in glioma-induced rats and also on the phenotypic markers of endothelial cells (CD31 and CD34). The parameters used were zymography, western blot, and flow cytometric analyses. It was observed that T11TS administration significantly downregulates the expression of matrix metalloproteinase-2 and -9 along with its ligand integrin αv and upregulates TIMP-1 and TIMP-2. In situ immunofluorescence and FACS results revealed that T11TS administration decreased the expression of the phenotypic markers (CD31/PECAM1, CD34), inhibiting the cell grip and also downregulating TGF-ß1 expression (ELISA) from microglia cells in the glioma microenvironment. These results suggest that T11TS suppresses the expression of positive angiogenic growth factors and potentiates the expression of negative regulators in glioma-associated endothelial cells (ECs), resulting in an anti-angiogenic effect on glioma-induced angiogenesis.


Subject(s)
Angiogenesis Inhibitors/pharmacology , Endothelial Cells/metabolism , Glioma/metabolism , Glycopeptides/pharmacology , Neovascularization, Pathologic/metabolism , Animals , Blotting, Western , Endothelial Cells/drug effects , Flow Cytometry , Fluorescent Antibody Technique , Glioma/blood supply , Integrin alphaV/metabolism , Matrix Metalloproteinases/metabolism , Rats , Tissue Inhibitor of Metalloproteinases/metabolism , Transforming Growth Factor beta1/metabolism
17.
Cell Immunol ; 284(1-2): 172-81, 2013.
Article in English | MEDLINE | ID: mdl-23994239

ABSTRACT

T11 target structure (T11TS), a membrane glycoprotein has been documented with anti neoplastic activity in glioma bearing animal model in our lab. In this study, we have evaluated the phagocytic potential, expression of VEGF, TNF-α in T11TS treated and untreated macrophages in all four grades of glioma. The data indicates the significant enhancement of phagocytosis in T11TS treated macrophages of grades I and II glioma. There was significant up regulation in TNF-α and significant down regulation in VEGF expression in T11TS treated macrophages in grade I and II glioma. We also attempted to know any possible apoptotic role of T11TS in tumor cells by comparing Bax and Bcl2 in treated and untreated tumor cells of all four grades. We found significant up regulation in Bax expression and down regulation in Bcl2 expression of grades I and II glioma. The outcome may help in pushing this molecule into pharmaceutical domain.


Subject(s)
Brain Neoplasms/immunology , CD2 Antigens/pharmacology , Carbamates/therapeutic use , Glioma/immunology , Macrophages/immunology , Adolescent , Adult , Apoptosis/immunology , Brain Neoplasms/drug therapy , Brain Neoplasms/pathology , CD2 Antigens/immunology , Child , Enzyme-Linked Immunosorbent Assay , Female , Flow Cytometry , Glioma/drug therapy , Glioma/pathology , Humans , Macrophages/drug effects , Male , Middle Aged , Tumor Necrosis Factor-alpha/immunology , Vascular Endothelial Growth Factor A/immunology , Young Adult , bcl-2-Associated X Protein/immunology
18.
J Neurooncol ; 113(1): 13-25, 2013 May.
Article in English | MEDLINE | ID: mdl-23471571

ABSTRACT

The crucial role of angiogenesis in malignant glioma progression makes it a potential target of therapeutic intervention in glioma. Previous studies from our lab showed that sheep erythrocyte membrane glycopeptide T11-target structure (T11TS) has potent anti-neoplastic and immune stimulatory effects in rodent glioma model. In the present study we investigated the anti-angiogenic potential of T11TS and deciphered the underlying molecular mechanism of its anti-angiogenic action in malignant glioma. Vascular endothelial growth factor (VEGF) signaling is crucial for initiating tumor angiogenic responses. The present preclinical study was designed to evaluate the effect of T11TS therapy on VEGF and VEGFR-2 expression in glioma associated brain endothelial cells and to determine the effects of in vivo T11TS administration on expression of PTEN and downstream pro-survival PI3K/Akt/eNOS pathway proteins in glioma associated brain endothelial cells. T11TS therapy in rodent glioma model significantly downregulated expression of VEGF along with its receptor VEGFR-2 and inhibited the expression of pro-survival PI3K/Akt/eNOS proteins in glioma associated brain endothelial cells. Furthermore, T11TS therapy in glioma induced rats significantly upregulated brain endothelial cell PTEN expression, inhibited eNOS phosphorylation and production of nitric oxide in glioma associated brain endothelial cells. Taken together our findings suggest that T11TS can be introduced as an effective angiogenesis inhibitor in human glioma as T11TS targets multiple levels of angiogenic signaling cascade impeding glioma neovascularisation.


Subject(s)
Brain Neoplasms/metabolism , CD2 Antigens/pharmacology , Glioma/metabolism , Signal Transduction/drug effects , Vascular Endothelial Growth Factor A/metabolism , Animals , Brain/drug effects , Brain/metabolism , Brain Neoplasms/blood supply , Disease Models, Animal , Endothelial Cells/drug effects , Endothelial Cells/metabolism , Female , Flow Cytometry , Fluorescent Antibody Technique , Glioma/blood supply , Immunoblotting , Male , Neovascularization, Pathologic/metabolism , Nitric Oxide Synthase Type III/metabolism , PTEN Phosphohydrolase/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Rats , Signal Transduction/physiology , Up-Regulation
19.
Asian Pac J Cancer Prev ; 13(6): 2943-8, 2012.
Article in English | MEDLINE | ID: mdl-22938487

ABSTRACT

Arsenic exposure is a serious health hazard worldwide. We have previously established that it may result in immune suppression by upregulating Th2 cytokines while downregulating Th1 cytokines and causing lymphocytic death. Treatment modalities for arsenic poisoning have mainly been restricted to the use of chelating agents in the past. Only recently have combination therapies using a chelating agent in conjunction with other compounds such as anti-oxidants, micronutrients and various plant products, been introduced. In the present study, we used T11TS, a novel immune potentiating glycopeptide alone and in combination with the sulfhydryl-containing chelator, mono-iso-amyl-dimarcaptosuccinic acid (MiADMSA) as a therapeutic regimen to combat arsenic toxicity in a mouse model. Results indicated that Th1 cytokines such as TNF-α, IFNγ, IL12 and the Th2 cytokines such as IL4, IL6, IL10 which were respectively downregulated and upregulated following arsenic induction were more efficiently restored to their near normal levels by T11TS alone in comparison with the combined regimen. Similar results were obtained with the apoptotic proteins studied, FasL, BAX, BCL2 and the caspases 3, 8 and 9, where again T11TS proved more potent than in combination with MiADMSA in preventing lymphocyte death. The results thus indicate that T11TS alone is more efficient in immune re-establishment after arsenic exposureas compared to combination therapy with T11TS+MiADMSA.


Subject(s)
Arsenic Poisoning/drug therapy , CD2 Antigens/therapeutic use , Chelating Agents/therapeutic use , Succimer/analogs & derivatives , Animals , Apoptosis/drug effects , Arsenic/toxicity , CD2 Antigens/pharmacology , Cell Transformation, Neoplastic , Chelation Therapy/methods , Cytokines/metabolism , Drug Therapy, Combination , Environmental Exposure , Lymphocytes/drug effects , Mice , Oxidative Stress/drug effects , Succimer/pharmacology , Succimer/therapeutic use
20.
Cell Immunol ; 276(1-2): 176-86, 2012.
Article in English | MEDLINE | ID: mdl-22704241

ABSTRACT

T11 target structure (T11TS), a membrane glycoprotein has been documented with antineoplastic activity in animal model in our lab. Previously, in animal study we have documented T11TS induced cytotoxic abrogation of tumor cells. Encouraged by these established findings by our group and as prerequisite for clinical trial, this study has been designed to assess the cytotoxic potential of the patient's lymphocytes in in vitro study of autologous human glioma as modulated by T11TS. Meningioma samples were chosen as disease control group. The data produced indicates T11TS induced up regulation of cytotoxicity of T lymphocytes in grade I and II glioma. Significant enhancement of cytotoxic protein, perforin and granzyme suggest cytotoxic death of T11TS induced target tumor. Also, T11TS downregulates the TGF-ß secretion in grade I and II tumor cells. These preliminary findings may help in pushing this molecule into pharmaceutical domain.


Subject(s)
Cytotoxicity, Immunologic , Glioma/immunology , Glycoproteins/immunology , T-Lymphocytes/immunology , Adolescent , Adult , Animals , Child , Female , Glioma/pathology , Glycoproteins/isolation & purification , Humans , Male , Middle Aged , Neoplasm Grading , Phenotype , Sheep , Tumor Cells, Cultured , Young Adult
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