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1.
Am J Hum Genet ; 101(3): 417-427, 2017 Sep 07.
Article in English | MEDLINE | ID: mdl-28886342

ABSTRACT

Individuals with Dupuytren disease (DD) are commonly seen by physicians and surgeons across multiple specialties. It is an increasingly common and disabling fibroproliferative disorder of the palmar fascia, which leads to flexion contractures of the digits, and is associated with other tissue-specific fibroses. DD affects between 5% and 25% of people of European descent and is the most common inherited disease of connective tissue. We undertook the largest GWAS to date in individuals with a surgically validated diagnosis of DD from the UK, with replication in British, Dutch, and German individuals. We validated association at all nine previously described signals and discovered 17 additional variants with p ≤ 5Ā Ć— 10-8. As a proof of principle, we demonstrated correlation of the high-risk genotype at the statistically most strongly associated variant with decreased secretion of the soluble WNT-antagonist SFRP4, in surgical specimen-derived DD myofibroblasts. These results highlight important pathways involved in the pathogenesis of fibrosis, including WNT signaling, extracellular matrix modulation, and inflammation. In addition, many associated loci contain genes that were hitherto unrecognized as playing a role in fibrosis, opening up new avenues of research that may lead to novel treatments for DD and fibrosis more generally. DD represents an ideal human model disease for fibrosis research.


Subject(s)
Biomarkers/analysis , Dupuytren Contracture/genetics , Fibrosis/genetics , Genome-Wide Association Study/methods , Polymorphism, Single Nucleotide/genetics , Case-Control Studies , Cells, Cultured , Cohort Studies , Dupuytren Contracture/pathology , Fibrosis/pathology , Gene Expression Profiling , Genotype , Humans , Myofibroblasts/metabolism , Myofibroblasts/pathology , Proto-Oncogene Proteins/genetics , Proto-Oncogene Proteins/metabolism , Wnt Proteins/genetics , Wnt Proteins/metabolism
2.
J Shoulder Elbow Surg ; 25(10): 1561-70, 2016 Oct.
Article in English | MEDLINE | ID: mdl-27131575

ABSTRACT

BACKGROUND: Progressive cellular and extracellular matrix (ECM) changes related to age and disease severity have been demonstrated in rotator cuff tendon tears. Larger rotator cuff tears demonstrate structural abnormalities that potentially adversely influence healing potential. This study aimed to gain greater insight into the relationship of pathologic changes to tear size by analyzing gene expression profiles from normal rotator cuff tendons, small rotator cuff tears, and large rotator cuff tears. METHODS: We analyzed gene expression profiles of 28 human rotator cuff tendons using microarrays representing the entire genome; 11 large and 5 small torn rotator cuff tendon specimens were obtained intraoperatively from tear edges, which we compared with 12 age-matched normal controls. We performed real-time polymerase chain reaction and immunohistochemistry for validation. RESULTS: Torn rotator cuff tendons demonstrated upregulation of a number of key genes, such as matrix metalloproteinase 3, 10, 12, 13, 15, 21, and 25; a disintegrin and metalloproteinase (ADAM) 12, 15, and 22; and aggrecan. Amyloid was downregulated in all tears. Small tears displayed upregulation of bone morphogenetic protein 5. Chemokines and cytokines that may play a role in chemotaxis were altered; interleukins 3, 10, 13, and 15 were upregulated in tears, whereas interleukins 1, 8, 11, 18, and 27 were downregulated. CONCLUSIONS: The gene expression profiles of normal controls and small and large rotator cuff tear groups differ significantly. Extracellular matrix remodeling genes were found to contribute to rotator cuff tear pathogenesis. Rotator cuff tears displayed upregulation of a number of matrix metalloproteinase (3, 10, 12, 13, 15, 21, and 25), a disintegrin and metalloproteinase (ADAM 12, 15, and 22) genes, and downregulation of some interleukins (1, 8, and 27), which play important roles in chemotaxis. These gene products may potentially have a role as biomarkers of failure of healing or therapeutic targets to improve tendon healing.


Subject(s)
Gene Expression Profiling , Rotator Cuff Injuries/genetics , ADAM Proteins/genetics , ADAM Proteins/metabolism , Case-Control Studies , Down-Regulation , Humans , Immunohistochemistry , Interleukins/genetics , Interleukins/metabolism , Matrix Metalloproteinases/genetics , Matrix Metalloproteinases/metabolism , Microarray Analysis , Principal Component Analysis , Real-Time Polymerase Chain Reaction , Retrospective Studies , Rotator Cuff Injuries/pathology , Up-Regulation
3.
Connect Tissue Res ; 55(5-6): 397-402, 2014.
Article in English | MEDLINE | ID: mdl-25166893

ABSTRACT

There is increasing evidence for a progressive extracellular matrix change in rotator cuff disease progression. Directly surrounding the cell is the pericellular matrix, where assembly of matrix aggregates typically occurs making it critical in the response of tendon cells to pathological conditions. Studies in animal models have identified type VI collagen, fibrillin-1 and elastin to be located in the pericellular matrix of tendon and contribute in maintaining the structural and biomechanical integrity of tendon. However, there have been no reports on the localization of these proteins in human tendon biopsies. This study aimed to characterize the distribution of these ECM components in human rotator cuffs and gain greater insight into the relationship of pathology to tear size by analyzing the distribution and expression profiles of these ECM components. Confocal microscopy confirmed the localization of these structural molecules in the pericellular matrix of the human rotator cuff. Tendon degeneration led to an increased visibility of these components with a significant disorganization in the distribution of type VI collagen. At the genetic level, an increase in tear size was linked to an increased transcription of type VI collagen and fibrillin-1 with no significant alteration in the elastin levels. This is the first study to confirm the localization of type VI collagen, elastin and fibrillin-1 in the pericellular region of human supraspinatus tendon and assesses the effect of tendon degeneration on these structures, thus providing a useful insight into the composition of human rotator cuff tears which can be instrumental in predicting disease prognosis.


Subject(s)
Collagen Type VI/metabolism , Elastic Tissue/metabolism , Extracellular Matrix Proteins/metabolism , Rotator Cuff Injuries , Rotator Cuff/metabolism , Analysis of Variance , DNA Primers/genetics , Fibrillin-1 , Fibrillins , Gene Expression Profiling , Humans , Immunohistochemistry , Microfilament Proteins/metabolism , Microscopy, Confocal , Real-Time Polymerase Chain Reaction
4.
J Immunother Cancer ; 10(2)2022 02.
Article in English | MEDLINE | ID: mdl-35131861

ABSTRACT

BACKGROUND: Despite significant progress in cancer immunotherapy in recent years, resistance to existing immune checkpoint therapies (ICT) is common. V-domain Ig suppressor of T cell activation (VISTA), a predominantly myeloid immune checkpoint regulator, represents a promising therapeutic target due to its role in suppressing proinflammatory antitumor responses in myeloid-enriched tumor microenvironments. However, uncertainty around the cognate VISTA ligand has made the development of effective anti-VISTA antibodies challenging. The expression of VISTA on normal immune cell subtypes argues for a neutralizing non-depleting antibody, however, previous reported anti-VISTA antibodies use IgG1 Fc isotypes that deplete VISTA+ cells by antibody dependent cellular cytotoxicity/complement dependent cytotoxicity and these antibodies have shown fast serum clearance and immune toxicities. METHOD: Here we used a rational antibody discovery approach to develop the first Fc-independent anti-VISTA antibody, HMBD-002, that binds a computationally predicted functional epitope within the C-C-loop, distinct from other known anti-VISTA antibodies. This epitope is species-conserved allowing robust in vitro and in vivo testing of HMBD-002 in human and murine models of immune activation and cancer including humanized mouse models. RESULTS: We demonstrate here that blockade by HMBD-002 inhibits VISTA binding to potential partners, including V-Set and Immunoglobulin domain containing 3, to reduce myeloid-derived suppression of T cell activity and prevent neutrophil migration. Analysis of immune cell milieu suggests that HMBD-002 treatment stimulates a proinflammatory phenotype characterized by a Th1/Th17 response, recapitulating a phenotype previously noted in VISTA knockout models. This mechanism of action is further supported by immune-competent syngenic and humanized mouse models of colorectal, breast and lung cancer where neutralizing VISTA, without depleting VISTA expressing cells, significantly inhibited tumor growth while decreasing infiltration of suppressive myeloid cells and increasing T cell activity. Finally, we did not observe either the fast serum clearance or immune toxicities that have been reported for IgG1 antibodies. CONCLUSION: In conclusion, we have shown that VISTA-induced immune suppression can be reversed by blockade of the functional C-C' loop region of VISTA with a first-in-class rationally targeted and non-depleting IgG4 isotype anti-VISTA antibody, HMBD-002. This antibody represents a highly promising novel therapy in the VISTA-suppressed ICT non-responder population.


Subject(s)
Immunosuppression Therapy/methods , Lymphocyte Activation/immunology , Neoplasms/immunology , Receptors, Fc/metabolism , Animals , Disease Models, Animal , Humans , Mice , Tumor Microenvironment
5.
Cancer Invest ; 29(2): 113-22, 2011 Feb.
Article in English | MEDLINE | ID: mdl-21261472

ABSTRACT

A comprehensive proteomic study utilizing 2D-DIGE and MALDI-TOF was used to assess the effect of inhibiting two different regulatory mechanisms of telomerase in glioma. RNAi was used to target hTERT and hsp90α. Inhibition of telomerase activity resulted in downregulation of various cytoskeletal proteins with correlative evidence of the involvement of telomerase in regulating the expression of vimentin. Inhibition of telomerase via sihTERT resulted in the downregulation of vimentin expression in glioma cell lines in a grade-specific manner. This study identified novel downstream role of telomerase in regulating the expression of vimentin, thereby affecting tumor progression and metastasis.


Subject(s)
Brain Neoplasms/pathology , Glioma/pathology , Neoplasm Proteins/analysis , Proteomics/methods , RNA Interference , Telomerase/physiology , Brain Neoplasms/chemistry , Cell Line, Tumor , Glioma/chemistry , Humans , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Telomerase/antagonists & inhibitors , Vimentin/genetics
6.
J Immunother Cancer ; 9(3)2021 03.
Article in English | MEDLINE | ID: mdl-33653801

ABSTRACT

Immune checkpoint inhibitors (ICIs) have improved overall survival for cancer patients, however, optimal duration of ICI therapy has yet to be defined. Given ICIs were first used to treat patients with metastatic melanoma, a condition that at the time was incurable, little attention was initially paid to how much therapy would be needed for a durable response. As the early immunotherapy trials have matured past 10 years, a significant per cent of patients have demonstrated durable responses; it is now time to determine whether patients have been overtreated, and if durable remissions can still be achieved with less therapy, limiting the physical and financial toxicity associated with years of treatment. Well-designed trials are needed to identify optimal duration of therapy, and to define biomarkers to predict who would benefit from shorter courses of immunotherapy. Here, we outline key questions related to health, financial and societal toxicities of over treating with ICI and present four unique clinical trials aimed at exposing criteria for early cessation of ICI. Taken together, there is a serious liability to overtreating patients with ICI and future work is warranted to determine when it is safe to stop ICI.


Subject(s)
Immune Checkpoint Inhibitors/administration & dosage , Neoplasms/drug therapy , Clinical Trials as Topic , Drug Administration Schedule , Evidence-Based Medicine , Humans , Immune Checkpoint Inhibitors/adverse effects , Neoplasms/immunology , Neoplasms/mortality , Neoplasms/pathology , Patient Safety , Risk Assessment , Risk Factors , Time Factors , Treatment Outcome
7.
PLoS One ; 16(6): e0253487, 2021.
Article in English | MEDLINE | ID: mdl-34161386

ABSTRACT

Although SARS-CoV-2-neutralizing antibodies are promising therapeutics against COVID-19, little is known about their mechanism(s) of action or effective dosing windows. We report the generation and development of SC31, a potent SARS-CoV-2 neutralizing antibody, isolated from a convalescent patient. Antibody-mediated neutralization occurs via an epitope within the receptor-binding domain of the SARS-CoV-2 Spike protein. SC31 exhibited potent anti-SARS-CoV-2 activities in multiple animal models. In SARS-CoV-2 infected K18-human ACE2 transgenic mice, treatment with SC31 greatly reduced viral loads and attenuated pro-inflammatory responses linked to the severity of COVID-19. Importantly, a comparison of the efficacies of SC31 and its Fc-null LALA variant revealed that the optimal therapeutic efficacy of SC31 requires Fc-mediated effector functions that promote IFNƎĀ³-driven anti-viral immune responses, in addition to its neutralization ability. A dose-dependent efficacy of SC31 was observed down to 5mg/kg when administered before viral-induced lung inflammatory responses. In addition, antibody-dependent enhancement was not observed even when infected mice were treated with SC31 at sub-therapeutic doses. In SARS-CoV-2-infected hamsters, SC31 treatment significantly prevented weight loss, reduced viral loads, and attenuated the histopathology of the lungs. In rhesus macaques, the therapeutic potential of SC31 was evidenced through the reduction of viral loads in both upper and lower respiratory tracts to undetectable levels. Together, the results of our preclinical studies demonstrated the therapeutic efficacy of SC31 in three different models and its potential as a COVID-19 therapeutic candidate.


Subject(s)
Antibodies, Neutralizing/immunology , Antibodies, Neutralizing/pharmacology , COVID-19/therapy , SARS-CoV-2/immunology , Angiotensin-Converting Enzyme 2/genetics , Animals , Antibodies, Neutralizing/metabolism , COVID-19/immunology , COVID-19/virology , Chemokines/blood , Chemokines/genetics , Chlorocebus aethiops , Convalescence , Cricetinae , Cytokines/blood , Cytokines/genetics , Disease Models, Animal , Dose-Response Relationship, Drug , Female , Humans , Immunoglobulin Fc Fragments/immunology , Immunoglobulin G/immunology , Immunoglobulin G/isolation & purification , Macaca mulatta , Male , Mice, Transgenic , Spike Glycoprotein, Coronavirus/metabolism , Vero Cells , Viral Load
8.
Cancer Invest ; 28(6): 608-14, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20210521

ABSTRACT

Hsp90alpha's vital role in cell cycle progression and apoptosis together with its presence in gliomas and absence in normal tissue, make it a credible target for cancer therapy. Three sets of dsRNA oligos designed to align different regions of the hsp90alpha sequence were used to downregulate hsp90alpha. SiRNA 1, 2, and 3 resulted in significant levels of silencing of hsp90alpha after 48 hr treatment (p < .0001). Concurrent treatment of the glioma cell line U87-MG with siRNA 1 and temozolomide (TMZ) resulted in a 13-fold reduction in the dose of TMZ required to achieve a similar effect if TMZ was used alone.


Subject(s)
Antineoplastic Agents, Alkylating/pharmacology , Brain Neoplasms/therapy , Dacarbazine/analogs & derivatives , Genetic Therapy/methods , Glioma/therapy , HSP90 Heat-Shock Proteins/metabolism , RNA Interference , RNA, Small Interfering/metabolism , Brain Neoplasms/genetics , Brain Neoplasms/metabolism , Brain Neoplasms/pathology , Cell Line, Tumor , Cell Survival/drug effects , Chemotherapy, Adjuvant , Cisplatin/pharmacology , Dacarbazine/pharmacology , Dose-Response Relationship, Drug , Gene Expression Regulation, Neoplastic , Glioma/genetics , Glioma/metabolism , Glioma/pathology , HSP90 Heat-Shock Proteins/genetics , Humans , Inhibitory Concentration 50 , RNA, Messenger/metabolism , Temozolomide , Time Factors , Transfection
9.
Mol Cancer Ther ; 19(2): 490-501, 2020 02.
Article in English | MEDLINE | ID: mdl-31911530

ABSTRACT

In recent years, HER3 has increasingly been implicated in the progression of a variety of tumor types and in acquired resistance to EGFR and HER2 therapies. Whereas EGFR and HER2 primarily signal through the MAPK pathway, HER3, as a heterodimer with EGFR or HER2, potently activates the PI3K pathway. Despite its critical role, previous attempts to target HER3 with neutralizing antibodies have shown disappointing efficacy in the clinic, most likely due to suboptimal and indirect mechanisms of action that fail to completely block heterodimerization; for example, tumors can escape inhibition of ligand binding by upregulating ligand-independent mechanisms of HER3 activation. We therefore developed 10D1F, a picomolar affinity, highly specific anti-HER3 neutralizing antibody that binds the HER3 heterodimerization interface, a region that was hitherto challenging to raise antibodies against. We demonstrate that 10D1F potently inhibits both EGFR:HER3 and HER2:HER3 heterodimerization to durably suppress activation of the PI3K pathway in a broad panel of tumor models. Even as a monotherapy, 10D1F shows superior inhibition of tumor growth in the same cell lines both in vitro and in mouse xenograft experiments, when compared with other classes of anti-HER3 antibodies. This includes models demonstrating ligand-independent activation of heterodimerization as well as constitutively activating mutations in the MAPK pathway. Possessing favorable pharmacokinetic and toxicologic profiles, 10D1F uniquely represents a new class of anti-HER3 neutralizing antibodies with a novel mechanism of action that offers significant potential for broad clinical benefit.10D1F is a novel anti-HER3 antibody that uniquely binds the receptor dimerization interface to block ligand-dependent and independent heterodimerization with EGFR/HER2 and thus more potently inhibits tumor growth than existing anti-HER3 antibodies.


Subject(s)
Immunoglobulin G/pharmacology , Neoplasms/therapy , Receptor, ErbB-3/antagonists & inhibitors , Receptor, ErbB-3/immunology , Animals , Epitopes/immunology , Female , Humans , Immunoglobulin G/immunology , Mice , Mice, Inbred BALB C , Mice, Nude , Neoplasms/immunology , Rats , Rats, Sprague-Dawley , Xenograft Model Antitumor Assays
10.
Mol Biol Rep ; 36(5): 1181-6, 2009 May.
Article in English | MEDLINE | ID: mdl-18581255

ABSTRACT

Telomerase expression strongly correlates with the grade of malignancy in glioma with inhibition illustrating a definite increase in chemosensitivity. This study was designed to investigate the effects of a green tea derivative, epigallocatechin-3-gallate (EGCG); together with either cisplatin or tamoxifen in glioma, and to investigate whether these effects are mediated through telomerase suppression. EGCG showed a significant cytotoxic effect on 1321N1 cells after 24 h and on U87-MG cells after 72 h (P < 0.001) without significantly affecting the normal astrocytes. Treatment with EGCG inhibited telomerase expression significantly (P < 0.01) and enhanced the effect of cisplatin and tamoxifen in both 1321N1 (P < 0.01) and U87-MG (P < 0.001) cells. EGCG, as a natural product has enormous potential to be an anti-cancer agent capable of enhancing tumour cell sensitivity to therapy.


Subject(s)
Antineoplastic Agents/pharmacology , Catechin/pharmacology , Cisplatin/pharmacology , Glioma/pathology , Tamoxifen/pharmacology , Catechin/analogs & derivatives , Cell Death/drug effects , Cell Line, Tumor , Cell Survival/drug effects , Drug Screening Assays, Antitumor , Gene Expression Regulation, Neoplastic/drug effects , Humans , Telomerase/genetics , Telomerase/metabolism
11.
Crit Rev Oncog ; 14(4): 203-15, 2008.
Article in English | MEDLINE | ID: mdl-19645682

ABSTRACT

Genomic analysis has provided a huge cohort of data that has shed light on the regulation and structure of telomerase and will continue to influence its study profoundly. However, genomic and proteomic data need to be collated in order to bridge the gap between telomerase regulation and its crucial role in carcinogenesis. This review highlights significant advances in understanding the regulation of telomerase activity in the realm of genomics and proteomics focusing on the importance of telomerase as a future prognostic and diagnostic marker.


Subject(s)
Proteomics/methods , Telomerase/physiology , Animals , Biomarkers, Tumor/metabolism , Biomarkers, Tumor/physiology , Epigenesis, Genetic/physiology , Gene Expression Regulation, Enzymologic , Gene Expression Regulation, Neoplastic , Humans , Neoplasms/diagnosis , Neoplasms/enzymology , Neoplasms/genetics , Prognosis , Protein Binding/physiology , Telomerase/genetics , Telomerase/metabolism
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