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ROCK-Myosin II drives fast rounded-amoeboid migration in cancer cells during metastatic dissemination. Analysis of human melanoma biopsies revealed that amoeboid melanoma cells with high Myosin II activity are predominant in the invasive fronts of primary tumors in proximity to CD206+CD163+ tumor-associated macrophages and vessels. Proteomic analysis shows that ROCK-Myosin II activity in amoeboid cancer cells controls an immunomodulatory secretome, enabling the recruitment of monocytes and their differentiation into tumor-promoting macrophages. Both amoeboid cancer cells and their associated macrophages support an abnormal vasculature, which ultimately facilitates tumor progression. Mechanistically, amoeboid cancer cells perpetuate their behavior via ROCK-Myosin II-driven IL-1α secretion and NF-κB activation. Using an array of tumor models, we show that high Myosin II activity in tumor cells reprograms the innate immune microenvironment to support tumor growth. We describe an unexpected role for Myosin II dynamics in cancer cells controlling myeloid function via secreted factors.
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Movimento Celular/fisiologia , Miosina Tipo II/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Adesão Celular , Linhagem Celular Tumoral , Movimento Celular/imunologia , Proteínas do Citoesqueleto , Feminino , Humanos , Interleucina-1alfa/metabolismo , Masculino , Melanoma/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos SCID , Pessoa de Meia-Idade , NF-kappa B/metabolismo , Neoplasias/imunologia , Neoplasias/metabolismo , Fosforilação , Proteômica , Receptor Cross-Talk/fisiologia , Transdução de Sinais , Microambiente Tumoral/imunologiaRESUMO
BACKGROUND: Survival rates for ovarian cancer remain poor, and monitoring and prediction of therapeutic response may benefit from additional markers. Ovarian cancers frequently overexpress Folate Receptor alpha (FRα) and the soluble receptor (sFRα) is measurable in blood. Here we investigated sFRα as a potential biomarker. METHODS: We evaluated sFRα longitudinally, before and during neo-adjuvant, adjuvant and palliative therapies, and tumour FRα expression status by immunohistrochemistry. The impact of free FRα on the efficacy of anti-FRα treatments was evaluated by an antibody-dependent cellular cytotoxicity assay. RESULTS: Membrane and/or cytoplasmic FRα staining were observed in 52.7% tumours from 316 ovarian cancer patients with diverse histotypes. Circulating sFRα levels were significantly higher in patients, compared to healthy volunteers, specifically in patients sampled prior to neoadjuvant and palliative treatments. sFRα was associated with FRα cell membrane expression in the tumour. sFRα levels decreased alongside concurrent tumour burden in patients receiving standard therapies. High concentrations of sFRα partly reduced anti-FRα antibody tumour cell killing, an effect overcome by increased antibody doses. CONCLUSIONS: sFRα may present a non-invasive marker for tumour FRα expression, with the potential for monitoring patient response to treatment. Larger, prospective studies should evaluate FRα for assessing disease burden and response to systemic treatments.
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Neoplasias Ovarianas , Feminino , Humanos , Receptor 1 de Folato/metabolismo , Receptor 1 de Folato/uso terapêutico , Neoplasias Ovarianas/patologia , Estudos Prospectivos , Resultado do TratamentoRESUMO
B-cell receptor activation, occurring within lymph nodes, plays a key role in the pathogenesis of chronic lymphocytic leukemia and is linked to prognosis. As well as activation of downstream signaling, receptor ligation triggers internalization, transit to acidified endosomes and degradation of ligand-receptor complexes. Herein, we investigated the relationship between these two processes in normal and leukemic B cells. We found that leukemic B cells, particularly anergic cases lacking the capacity to initiate downstream signaling, internalize and accumulate ligand in acidified endosomes more efficiently than normal B cells. Furthermore, ligation of either surface CD79B, a B-cell receptor component required for downstream signaling, or surface Immunoglobulin M (IgM) by cognate agonistic antibody, showed that the two molecules internalize independently of each other in leukemic but not normal B cells. Since association with surface CD79B is required for surface retention of IgM, this suggests that uncoupling of B-cell receptor internalization from signaling may be due to the dissociation of these two molecules in leukemic cells. A comparison of lymph node with peripheral blood cells from chronic lymphocytic leukemia patients showed that, despite recent B-cell receptor activation, lymph node B cells expressed higher levels of surface IgM. This surprising finding suggests that the B-cell receptors of lymph node- and peripheral blood-derived leukemic cells might be functionally distinct. Finally, long-term therapy with the Bruton's tyrosine kinase inhibitors ibrutinib or acalabrutinib resulted in a switch to an anergic pattern of B-cell receptor function with reduced signaling capacity, surface IgM expression and more efficient internalization.
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Leucemia Linfocítica Crônica de Células B/patologia , Receptores de Antígenos de Linfócitos B/metabolismo , Transdução de Sinais , Adenina/análogos & derivados , Tirosina Quinase da Agamaglobulinemia/antagonistas & inibidores , Benzamidas/uso terapêutico , Antígenos CD79/metabolismo , Anergia Clonal , Endocitose , Humanos , Imunoglobulina M/metabolismo , Piperidinas , Pirazinas/uso terapêutico , Pirazóis/uso terapêutico , Pirimidinas/uso terapêuticoAssuntos
Imunoglobulina E/imunologia , Neoplasias/imunologia , Neoplasias/terapia , Proteínas Recombinantes/imunologia , Alérgenos/imunologia , Anticorpos/imunologia , Antígenos de Neoplasias/imunologia , Linhagem Celular , Linhagem Celular Tumoral , Células HEK293 , Humanos , Hipersensibilidade/imunologia , Imunoterapia/métodos , Proteínas de Membrana/imunologiaRESUMO
AIM: In 2022, in Italy, general practitioners (GPs) have been allowed to prescribe SGLT2i in Type 2 Diabetes (T2D) under National Health Service (NHS) reimbursement. In the pivotal clinical trial named DECLARE-TIMI 58, dapagliflozin reduced the risk of hospitalization for heart failure, CV death and kidney disease progression compared to placebo in a population of T2D patients. This study evaluated the health and economic impact of dapagliflozin for T2D patients who had or were at risk for atherosclerotic cardiovascular disease in the Italian GPs setting. METHODS: A budget impact model was developed to assess the health and economic impact of introducing dapagliflozin in GPs setting. The analysis was conducted by adopting the Italian NHS perspective and a 3-year time horizon. The model estimated and compared the health outcomes and direct medical costs associated with a scenario with dapagliflozin and other antidiabetic therapies available for GPs prescription (scenario B) and a scenario where only other antidiabetic therapies are available (scenario A). Rates of occurrence of cardiovascular and renal complications as well as adverse events were captured from DECLARE-TIMI 58 trial and the literature, while cost data were retrieved from the Italian tariff and the literature. One-way sensitivity analyses were conducted to test the impact of model parameters on the budget impact. RESULTS: The model estimated around 442.000 patients eligible for the treatment with dapagliflozin in the GPs setting for each simulated year. The scenario B compared to scenario A was associated with a reduction in the occurrence of cardiovascular and renal complication (-1.83%) over the 3 years simulated. Furthermore, the scenario A allowed for an overall cost saving of 102,692,305: 14,521,464 in the first year, 33,007,064 in the second and 55,163,777 in the third. The cost of cost of drug acquisition, the probability of cardiovascular events and the percentage of patients potentially eligible to the treatment were the factor with largest impact on the results. CONCLUSIONS: The use of dapagliflozin in GPs setting reduce the number of CVD events, kidney disease progression and healthcare costs in Italy. These data should be considered to optimize the value produced for the T2D patients who had or were at risk for atherosclerotic cardiovascular disease.
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Aterosclerose , Compostos Benzidrílicos , Diabetes Mellitus Tipo 2 , Glucosídeos , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/economia , Diabetes Mellitus Tipo 2/complicações , Compostos Benzidrílicos/economia , Compostos Benzidrílicos/uso terapêutico , Itália/epidemiologia , Glucosídeos/uso terapêutico , Glucosídeos/economia , Aterosclerose/economia , Aterosclerose/tratamento farmacológico , Clínicos Gerais/estatística & dados numéricos , Clínicos Gerais/economia , Orçamentos/estatística & dados numéricos , Análise Custo-Benefício , Doenças Cardiovasculares/economia , Doenças Cardiovasculares/prevenção & controle , Doenças Cardiovasculares/epidemiologia , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Inibidores do Transportador 2 de Sódio-Glicose/economia , Hipoglicemiantes/economia , Hipoglicemiantes/uso terapêutico , Masculino , Feminino , Pessoa de Meia-IdadeRESUMO
Human Papilloma Virus (HPV) infection and HPV-related cancers can be prevented through vaccinations and mass cervical screening programmes. The Ministry of Health in Italy provides recommendations on primary and secondary prevention of HPV-related diseases, but the 19 Italian regions and 2 autonomous provinces have organisational and decision-making autonomy, with differences in the strategies for offering prevention. The aim of this study is to describe the HPV vaccination and cervical screening offered in all Italian regions. Regional official documents up until 31 December 2021 were first identified. Subsequently, primary and secondary prevention experts from each region were interviewed to validate the previously collected data. The National Immunisation Plan (NIP) 2017-2019 recommends HPV vaccination from the age of 11 for both sexes, with a coverage target of 95%. HPV vaccination is offered free of charge or co-payment. All regions have screening programmes for cervical cancer, using PAP or HPV-DNA tests every three to five years. All regions have an electronic registry for vaccination and screening status. All regions have developed awareness-raising campaigns. It is important to harmonise regional policies with the implementation of information systems integration. The collected data could enhance both regional and national public health initiatives, bolstering the resilience of vaccination programs.
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Introduction: The underdiagnosis of chronic kidney disease (CKD) remains a significant public health concern. The Early chroNic kiDney disease pOint of caRe Screening (ENDORSE) project aimed to evaluate the clinical and economic implications of a targeted training intervention for general practitioners (GPs) to enhance CKD awareness and early diagnosis. Methods: Data on estimated Glomerular Filtration Rate (eGFR) and Urinary Albumin-Creatinine Ratio (uACR) were collected by 53 Italian GPs from 112,178 patients at baseline and after six months. The intervention involved six months of hybrid training provided by 11 nephrologists, which included formal lectures, instant messaging support, and joint visits for complex cases. Results: The results demonstrated a substantial increase in the use of eGFR (+44.7%) and uACR (+95.2%) tests. This led to a 128.9% rise in the number of individuals screened for CKD using the KDIGO classification, resulting in a 62% increase in CKD diagnoses. The intervention's impact was particularly notable in high-risk groups, including patients with type 2 diabetes, hypertension, and heart failure. Discussion: A budget impact analysis projected cumulative five-year savings of 1.7 million for the study cohort. When these findings were extrapolated to the entire Italian CKD population, potential savings were estimated at 106.6 million, highlighting significant cost savings for the national health service. The clinical simulation assumed that early diagnosed CKD patients would be treated according to current indications for dapagliflozin, which slows disease progression. Conclusion: The ENDORSE model demonstrated that targeted training for GPs can significantly improve early CKD detection, leading to better patient outcomes and considerable economic benefits. This approach shows promise for broader implementation to address the underdiagnosis of CKD on a national and potentially international scale.
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B cells are known to contribute to the anti-tumor immune response, especially in immunogenic tumors such as melanoma, yet humoral immunity has not been characterized in these cancers to detail. Here we show comprehensive phenotyping in samples of circulating and tumor-resident B cells as well as serum antibodies in melanoma patients. Memory B cells are enriched in tumors compared to blood in paired samples and feature distinct antibody repertoires, linked to specific isotypes. Tumor-associated B cells undergo clonal expansion, class switch recombination, somatic hypermutation and receptor revision. Compared with blood, tumor-associated B cells produce antibodies with proportionally higher levels of unproductive sequences and distinct complementarity determining region 3 properties. The observed features are signs of affinity maturation and polyreactivity and suggest an active and aberrant autoimmune-like reaction in the tumor microenvironment. Consistent with this, tumor-derived antibodies are polyreactive and characterized by autoantigen recognition. Serum antibodies show reactivity to antigens attributed to autoimmune diseases and cancer, and their levels are higher in patients with active disease compared to post-resection state. Our findings thus reveal B cell lineage dysregulation with distinct antibody repertoire and specificity, alongside clonally-expanded tumor-infiltrating B cells with autoimmune-like features, shaping the humoral immune response in melanoma.
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Linfócitos B , Melanoma , Humanos , Melanoma/genética , Anticorpos , Imunidade Humoral , Autoantígenos/genética , Microambiente TumoralRESUMO
Outcomes for half of patients with melanoma remain poor despite standard-of-care checkpoint inhibitor therapies. The prevalence of the melanoma-associated antigen chondroitin sulfate proteoglycan 4 (CSPG4) expression is ~70%, therefore effective immunotherapies directed at CSPG4 could benefit many patients. Since IgE exerts potent immune-activating functions in tissues, we engineer a monoclonal IgE antibody with human constant domains recognizing CSPG4 to target melanoma. CSPG4 IgE binds to human melanomas including metastases, mediates tumoricidal antibody-dependent cellular cytotoxicity and stimulates human IgE Fc-receptor-expressing monocytes towards pro-inflammatory phenotypes. IgE demonstrates anti-tumor activity in human melanoma xenograft models engrafted with human effector cells and is associated with enhanced macrophage infiltration, enriched monocyte and macrophage gene signatures and pro-inflammatory signaling pathways in the tumor microenvironment. IgE prolongs the survival of patient-derived xenograft-bearing mice reconstituted with autologous immune cells. No ex vivo activation of basophils in patient blood is measured in the presence of CSPG4 IgE. Our findings support a promising IgE-based immunotherapy for melanoma.
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Melanoma , Proteoglicanas , Humanos , Camundongos , Animais , Proteoglicanas/metabolismo , Antígenos , Proteoglicanas de Sulfatos de Condroitina , Melanoma/metabolismo , Anticorpos Monoclonais/farmacologia , Imunoglobulina E , Microambiente TumoralRESUMO
IgE antibodies elicit powerful immune responses, recruiting effector cells to tumors more efficiently and with greater cytotoxicity than IgG antibodies. Consequently, IgE antibodies are a promising alternative to conventional IgG-based therapies in oncology (AllergoOncology). As the pharmacokinetics of IgE antibodies are less well understood, we used molecular imaging in mice to compare the distribution and elimination of IgE and IgG antibodies targeting the human tumor-associated antigen chondroitin sulfate proteoglycan 4 (CSPG4). Anti-CSPG4 IgE and IgG1 antibodies with human Fc domains were radiolabeled with 111In. CSPG4-expressing A375 human melanoma xenografts implanted in NOD-scid IL2rg-/- mice were also engrafted with human immune cells by intravenous administration. 111In-anti-CSPG4 antibodies were administered intravenously. Their distribution was determined by single-photon emission computed tomography (SPECT) and ex vivo gamma-counting over 120 h. SPECT imaging was conducted from 0 to 60 min after antibody administration to precisely measure the early phase of IgE distribution. 111In-labeled anti-CSPG4 IgG and IgE showed serum stability in vitro of >92% after 5 days. In A375 xenograft-bearing mice, anti-CSPG4 IgE showed much faster blood clearance and higher accumulation in the liver compared to anti-CSPG4 IgG. However, tumor-to-blood and tumor-to-muscle ratios were similar between the antibody isotypes and higher compared with a non-tumor-targeting isotype control IgE. IgE excretion was much faster than IgG. In non-tumor-bearing animals, early SPECT imaging revealed a blood clearance half-life of 10 min for IgE. Using image-based quantification, we demonstrated that the blood clearance of IgE is much faster than that of IgG while the two isotypes showed comparable tumor-to-blood ratios.
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Antígenos de Neoplasias , Melanoma , Animais , Imunoglobulina E , Imunoglobulina G , Camundongos , Camundongos Endogâmicos NOD , Imagem MolecularRESUMO
BACKGROUND: Cancer immunotherapy with monoclonal antibodies and chimeric antigen receptor (CAR) T cell therapies can benefit from selection of new targets with high levels of tumor specificity and from early assessments of efficacy and safety to derisk potential therapies. METHODS: Employing mass spectrometry, bioinformatics, immuno-mass spectrometry and CRISPR/Cas9 we identified the target of the tumor-specific SF-25 antibody. We engineered IgE and CAR T cell immunotherapies derived from the SF-25 clone and evaluated potential for cancer therapy. RESULTS: We identified the target of the SF-25 clone as the tumor-associated antigen SLC3A2, a cell surface protein with key roles in cancer metabolism. We generated IgE monoclonal antibody, and CAR T cell immunotherapies each recognizing SLC3A2. In concordance with preclinical and, more recently, clinical findings with the first-in-class IgE antibody MOv18 (recognizing the tumor-associated antigen Folate Receptor alpha), SF-25 IgE potentiated Fc-mediated effector functions against cancer cells in vitro and restricted human tumor xenograft growth in mice engrafted with human effector cells. The antibody did not trigger basophil activation in cancer patient blood ex vivo, suggesting failure to induce type I hypersensitivity, and supporting safe therapeutic administration. SLC3A2-specific CAR T cells demonstrated cytotoxicity against tumor cells, stimulated interferon-γ and interleukin-2 production in vitro. In vivo SLC3A2-specific CAR T cells significantly increased overall survival and reduced growth of subcutaneous PC3-LN3-luciferase xenografts. No weight loss, manifestations of cytokine release syndrome or graft-versus-host disease, were detected. CONCLUSIONS: These findings identify efficacious and potentially safe tumor-targeting of SLC3A2 with novel immune-activating antibody and genetically modified cell therapies.
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Cadeia Pesada da Proteína-1 Reguladora de Fusão/imunologia , Imunoglobulina E/metabolismo , Imunoterapia/métodos , Receptores de Antígenos Quiméricos/imunologia , Animais , Humanos , CamundongosRESUMO
IgE monoclonal antibodies hold great potential for cancer therapy. Preclinical in vivo systems, particularly those in which the antibody recognizes the host species target antigen and binds to cognate Fc receptors, are often the closest approximation to human exposure and represent a key challenge for evaluating the safety of antibody-based therapies. We sought to develop an immunocompetent rat system to assess the safety of a rodent anti-tumor IgE, as a surrogate for the human therapeutic candidate. We generated a rat IgE against the human tumor-associated antigen chondroitin sulfate proteoglycan 4 (CSPG4) and cross-reactive for the rat antigen. We analyzed CSPG4 distribution in normal rat and human tissues and investigated the in vivo safety of the antibody by monitoring clinical signs and molecular biomarkers after systemic administration to immunocompetent rats. Human and rat CSPG4 expression in normal tissues were comparable. Animals receiving antibody exhibited transient mild to moderate adverse events accompanied by mild elevation of serum tryptase, but not of angiotensin II or cytokines implicated in allergic reactions or cytokine storm. In the long term, repeated antibody administration was well tolerated, with no changes in animal body weight, liver and kidney functions or blood cell counts. This model provides preclinical support for the safety profiling of IgE therapeutic antibodies. Due to the comparable antigen tissue distribution in human and rat, this model may also comprise an appropriate tool for proof-of-concept safety evaluations of different treatment approaches targeting CSPG4.
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Antígenos de Neoplasias/imunologia , Antineoplásicos Imunológicos/administração & dosagem , Proteoglicanas de Sulfatos de Condroitina/imunologia , Imunoglobulina E/administração & dosagem , Proteínas de Membrana/imunologia , Proteínas Recombinantes de Fusão/administração & dosagem , Animais , Citotoxicidade Celular Dependente de Anticorpos , Antineoplásicos Imunológicos/efeitos adversos , Linhagem Celular Tumoral , Reações Cruzadas , Feminino , Humanos , Imunização Secundária , Imunocompetência , Imunoglobulina E/efeitos adversos , Camundongos , Ratos , Proteínas Recombinantes de Fusão/efeitos adversosRESUMO
Despite emerging targeted and immunotherapy treatments, no monoclonal antibodies or antibody-drug conjugates (ADCs) directly targeting tumor cells are currently approved for melanoma therapy. The tumor-associated antigen chondroitin sulphate proteoglycan 4 (CSPG4), a neural crest glycoprotein over-expressed on 70% of melanomas, contributes to proliferative signaling pathways, but despite highly tumor-selective expression it has not yet been targeted using ADCs. We developed a novel ADC comprising an anti-CSPG4 antibody linked to a DNA minor groove-binding agent belonging to the novel pyrridinobenzodiazepine (PDD) class. Unlike conventional DNA-interactive pyrrolobenzodiazepine (PBD) dimer payloads that cross-link DNA, PDD-based payloads are mono-alkylating agents but have similar efficacy and substantially enhanced tolerability profiles compared to PBD-based cross-linkers. We investigated the anti-tumor activity and safety of the anti-CSPG4-(PDD) ADC in vitro and in human melanoma xenografts. Anti-CSPG4-(PDD) inhibited CSPG4-expressing melanoma cell growth and colony formation and triggered apoptosis in vitro at low nanomolar to picomolar concentrations without off-target Fab-mediated or Fc-mediated toxicity. Anti-CSPG4-(PDD) restricted xenograft growth in vivo at 2 mg/kg doses. One 5 mg/kg injection triggered tumor regression in the absence of overt toxic effects or of acquired residual tumor cell resistance. This anti-CSPG4-(PDD) can deliver a highly cytotoxic DNA mono-alkylating payload to CSPG4-expressing tumors at doses tolerated in vivo.
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Despite substantial clinical benefit of targeted and immune checkpoint blockade-based therapies in melanoma, resistance inevitably develops. We show cytoskeletal remodeling and changes in expression and activity of ROCK-myosin II pathway during acquisition of resistance to MAPK inhibitors. MAPK regulates myosin II activity, but after initial therapy response, drug-resistant clones restore myosin II activity to increase survival. High ROCK-myosin II activity correlates with aggressiveness, identifying targeted therapy- and immunotherapy-resistant melanomas. Survival of resistant cells is myosin II dependent, regardless of the therapy. ROCK-myosin II ablation specifically kills resistant cells via intrinsic lethal reactive oxygen species and unresolved DNA damage and limits extrinsic myeloid and lymphoid immunosuppression. Efficacy of targeted therapies and immunotherapies can be improved by combination with ROCK inhibitors.
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Citoesqueleto/metabolismo , Resistencia a Medicamentos Antineoplásicos , Melanoma/metabolismo , Miosina Tipo II/metabolismo , Animais , Antígeno B7-H1/metabolismo , Ciclo Celular , Linhagem Celular Tumoral , Dano ao DNA , Feminino , Humanos , Imunoterapia , Sistema de Sinalização das MAP Quinases , Masculino , Melanoma/imunologia , Melanoma/terapia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos Nus , Camundongos SCID , Estresse Oxidativo , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas B-raf/genética , Espécies Reativas de Oxigênio , Linfócitos T Reguladores/imunologia , Resultado do Tratamento , Microambiente Tumoral/imunologia , Quinases Associadas a rho/metabolismoRESUMO
Antibody-Drug Conjugates (ADCs) developed as a targeted treatment approach to deliver toxins directly to cancer cells are one of the fastest growing classes of oncology therapeutics, with eight ADCs and two immunotoxins approved for clinical use. However, selection of an optimum target and payload combination, to achieve maximal therapeutic efficacy without excessive toxicity, presents a significant challenge. We have developed a platform to facilitate rapid and cost-effective screening of antibody and toxin combinations for activity and safety, based on streptavidin-biotin conjugation. For antibody selection, we evaluated internalization by target cells using streptavidin-linked antibodies conjugated to biotinylated saporin, a toxin unable to cross cell membranes. For payload selection, we biotinylated toxins and conjugated them to antibodies linked to streptavidin to evaluate antitumour activity and pre-clinical safety. As proof of principle, we compared trastuzumab conjugated to emtansine via streptavidin-biotin (Trastuzumab-SB-DM1) to the clinically approved trastuzumab emtansine (T-DM1). We showed comparable potency in reduction of breast cancer cell survival in vitro and in growth restriction of orthotopic breast cancer xenografts in vivo. Our findings indicate efficient generation of functionally active ADCs. This approach can facilitate the study of antibody and payload combinations for selection of promising candidates for future ADC development.
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Antineoplásicos/química , Imunoconjugados/química , Toxinas Biológicas/química , Trastuzumab/química , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Biotina/química , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Feminino , Humanos , Imunoconjugados/farmacologia , Imunoconjugados/uso terapêutico , Maitansina/química , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Saporinas/química , Estreptavidina/química , Transplante Heterólogo , Trastuzumab/uso terapêuticoRESUMO
Human immunoglobulin E (IgE) is the most extensively glycosylated antibody isotype so glycans attached to the seven N-glycosites (NGS) in its Fab and Fc domains may modulate its functions. However, targeted modification of glycans in multiply glycosylated proteins remains a challenge. Here, we applied an in vivo approach that allows the manipulation of IgE N-glycans, using a trastuzumab equivalent IgE (HER2-IgE) as a model. Taking advantage of plant inherent features, i.e., synthesis of largely homogeneous complex N-glycans and susceptibility to glycan engineering, we generated targeted glycoforms of HER2-IgE largely resembling those found in serum IgE. Plant-derived HER2-IgE exhibited N-glycans terminating with GlcNAc, galactose or sialic acid, lacking, or carrying core fucose and xylose. We were able to not only modulate the five NGSs naturally decorated with complex N-glycans, but to also induce targeted glycosylation at the usually unoccupied NGS6, thus increasing the overall glycosylation content of HER2-IgE. Recombinant human cell-derived HER2-IgE exhibited large N-glycan heterogeneity. All HER2-IgE variants demonstrated glycosylation-independent binding to the target antigen and the high affinity receptor FcεRI, and subsequent similar capacity to trigger mast cell degranulation. In contrast, binding to the low affinity receptor CD23 (FcεRII) was modulated by the glycan profile, with increased binding to IgE variants with glycans terminating with GlcNAc residues. Here we offer an efficient in planta approach to generate defined glycoforms on multiply glycosylated IgE, allowing the precise exploration of glycosylation-dependent activities.
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BACKGROUND: Antibody Fc-driven engagement of macrophages is critical for evoking cellular activation and effector functions and influencing tumour-associated macrophage (TAM) recruitment. We previously reported that IgE class antibodies promote restriction of cancer growth in rodent models associated with significant TAM infiltration. However, the human macrophage-associated IgE-Fc Receptor (FcεR) axis remains unexplored. We investigated the effects of anti-tumour IgE stimulation on human macrophage activation. METHODS: Human blood monocyte-differentiated quiescent (M0), classically-(M1) and alternatively-(M2) activated macrophages were crosslinked with IgE and polyclonal antibodies to mimic immune complex formation. We examined surface marker expression, cytokine secretion, protein kinase phosphorylation and gene expression in IgE-stimulated macrophages and IgE antibody-dependent macrophage-mediated cytotoxicity (ADCC) against tumour cells. FINDINGS: A proportion (40%) of M2 and (<20%) M0 and M1 macrophages expressed the high-affinity IgE receptor FcεRI. IgE crosslinking triggered upregulation of co-stimulatory CD80, increased TNFα, IFNγ, IL-1ß, IL-12, IL-10, IL-13, CXCL9, CXCL11 and RANTES secretion by M0 and M2 and additionally enhanced MCP-1 by M2 macrophages. IgE-stimulated M1 macrophages retained secretion of pro-inflammatory cytokines. IgE crosslinking enhanced the FcεRI-dependent signalling pathway, including phosphorylation of the Lyn kinase, ERK1/2 and p38 in M2 macrophages and upregulated Lyn gene expression by M1 and M2 macrophages. Anti-tumour IgE engendered ADCC of cancer cells by all macrophage subsets. INTERPRETATION: IgE can engage and re-educate alternatively-activated macrophages towards pro-inflammatory phenotypes and prime all subsets to mediate anti-tumour functions. This points to IgE-mediated cascades with potential to activate immune stroma and may be significant in the clinical development of strategies targeting tumour-resident macrophages.
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Imunoglobulina E/imunologia , Mediadores da Inflamação/metabolismo , Ativação de Macrófagos/imunologia , Macrófagos/imunologia , Macrófagos/metabolismo , Neoplasias/imunologia , Neoplasias/metabolismo , Antígenos de Neoplasias/imunologia , Biomarcadores , Citocinas/metabolismo , Citotoxicidade Imunológica , Expressão Gênica , Humanos , Modelos Biológicos , Monócitos/imunologia , Monócitos/metabolismo , Neoplasias/mortalidade , Neoplasias/patologia , Fagocitose/genética , Fagocitose/imunologia , Prognóstico , Ligação Proteica/imunologia , Receptores de IgE/metabolismo , Transdução de SinaisRESUMO
The immune system employs several checkpoint pathways to regulate responses, maintain homeostasis and prevent self-reactivity and autoimmunity. Tumor cells can hijack these protective mechanisms to enable immune escape, cancer survival and proliferation. Blocking antibodies, designed to interfere with checkpoint molecules CTLA-4 and PD-1/PD-L1 and counteract these immune suppressive mechanisms, have shown significant success in promoting immune responses against cancer and can result in tumor regression in many patients. While inhibitors to CTLA-4 and the PD-1/PD-L1 axis are well-established for the clinical management of melanoma, many patients do not respond or develop resistance to these interventions. Concerted efforts have focused on combinations of approved therapies aiming to further augment positive outcomes and survival. While CTLA-4 and PD-1 are the most-extensively researched targets, results from pre-clinical studies and clinical trials indicate that novel agents, specific for checkpoints such as A2AR, LAG-3, IDO and others, may further contribute to the improvement of patient outcomes, most likely in combinations with anti-CTLA-4 or anti-PD-1 blockade. This review discusses the rationale for, and results to date of, the development of inhibitory immune checkpoint blockade combination therapies in melanoma. The clinical potential of new pipeline therapeutics, and possible future therapy design and directions that hold promise to significantly improve clinical prognosis compared with monotherapy, are discussed.
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Anticorpos Monoclonais/imunologia , Sistema Imunitário/efeitos dos fármacos , Sistema Imunitário/imunologia , Melanoma/imunologia , Melanoma/terapia , Animais , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Antígeno B7-H1/imunologia , Antígeno CTLA-4/imunologia , Humanos , Imunoterapia/métodosRESUMO
CD38 is a transmembrane exoenzyme that is associated with poor prognosis in chronic lymphocytic leukemia (CLL). High CD38 levels in CLL cells are linked to increased cell migration, but the molecular basis is unknown. CD38 produces nicotinic acid adenine dinucleotide phosphate and adenosine 5'-diphosphate-ribose, both of which can act to increase intracellular Ca2+ levels. Here we show that CD38 expression increases basal intracellular Ca2+ levels and stimulates CLL cell migration both with and without chemokine stimulation. We find that CD38 acts via intracellular Ca2+ to increase the activity of the Ras family GTPase Rap1, which is in turn regulated by the Ca2+-sensitive Rap1 guanine-nucleotide exchange factor RasGRP2. Both Rap1 and RasGRP2 are required for CLL cell migration, and RasGRP2 is polarized in primary CLL cells with high CD38 levels. These results indicate that CD38 promotes RasGRP2/Rap1-mediated CLL cell adhesion and migration by increasing intracellular Ca2+ levels.