Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 112
Filtrar
1.
Artigo em Inglês | MEDLINE | ID: mdl-38420990

RESUMO

AIMS: The objective of this study was to investigate the association and combined prognostic significance of the PD-L1, Smoothened protein and ß-catenin expressions in patients with clear cell renal cell carcinoma (ccRCC). METHODS: The PD-L1, Smoothened protein and ß-catenin expression were evaluated in 104 ccRCC patients. All studied tumor samples were acquired from nephrectomy specimens of primary tumors and not from biopsies or metastases. An indirect immunohistochemistry using polyclonal rabbit anti-Smoothened antibody, monoclonal mouse anti-human ß-catenin-1 antibody, immunohistochemical assay PD-L1 28-8 pharmDx using monoclonal rabbit anti-PD-L1 antibody and anti-VHL (C- terminal) rabbit antibody was used. Immunohistochemistry was scored semiquantitavely. RESULTS: Median overall survival (OS) was significantly better in patients with lower PD-L1 expression (≤5%), Smoothened protein (SMO) expression (<5%) or cytoplasmic ß-catenin expression (≤75%) than in patients with higher expressions of these biomarkers (P<0.001, P=0.047, and P<0.001, respectively). Membranous ß-catenin showed an opposite effect with its lower expression (≤75%) being associated with longer OS (P=0.020). There was significant association between PD-1 and PD-L1 expression (P=0.007) and significant association of tumor grade (WHO 2016) with membranous ß-catenin (P<0.001), cytoplasmic ß-catenin (P=0.005), pVHL (P=0.042), PD-L1 (P=0.049) and PD-1 (P=0.028) expression. CONCLUSION: The present study provides the first data on the potential association and combined prognostic significance of frequency of primary cilia, PD-L1, Smoothened protein and ß-catenin expression with the outcome in clear cell renal cell carcinoma.

2.
Virchows Arch ; 484(1): 103-117, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37962685

RESUMO

Branchioma is an uncommon benign neoplasm with an adult male predominance, typically occurring in the lower neck region. Different names have been used for this entity in the past (ectopic hamartomatous thymoma, branchial anlage mixed tumor, thymic anlage tumor, biphenotypic branchioma), but currently, the term branchioma has been widely accepted. Branchioma is composed of endodermal and mesodermal lineage derivatives, in particular epithelial islands, spindle cells, and mature adipose tissue without preexistent thymic tissue or evidence of thymic differentiation. Twenty-three branchiomas were evaluated morphologically. Eighteen cases with sufficient tissue were assessed by immunohistochemistry, next-generation sequencing (NGS) using the Illumina Oncology TS500 panel, and fluorescence in situ hybridization (FISH) using an RB1 dual-color probe. All cases showed a biphasic morphology of epithelial and spindle cells with intermingled fatty tissue. Carcinoma arising in branchioma was detected in three cases. The neoplastic cells showed strong AE1/3 immunolabeling (100%), while the spindle cells expressed CD34, p63, and SMA (100%); AR was detected in 40-100% of nuclei (mean, 47%) in 14 cases. Rb1 showed nuclear loss in ≥ 95% of neoplastic cells in 16 cases (89%), while two cases revealed retained expression in 10-20% of tumor cell nuclei. NGS revealed a variable spectrum of likely pathogenic variants (n = 5) or variants of unknown clinical significance (n = 6). Loss of Rb1 was detected by FISH in two cases. Recent developments support branchioma as a true neoplasm, most likely derived from the rudimental embryological structures of endoderm and mesoderm. Frequent Rb1 loss by immunohistochemistry and heterozygous deletion by FISH is a real pitfall and potential confusion with other Rb1-deficient head and neck neoplasms (i.e., spindle cell lipoma), especially in small biopsy specimens.


Assuntos
Branquioma , Neoplasias Epiteliais e Glandulares , Neoplasias da Retina , Retinoblastoma , Neoplasias de Tecidos Moles , Timoma , Neoplasias do Timo , Adulto , Humanos , Masculino , Feminino , Branquioma/patologia , Retinoblastoma/genética , Retinoblastoma/patologia , Hibridização in Situ Fluorescente , Neoplasias de Tecidos Moles/patologia , Biologia Molecular
3.
Microorganisms ; 11(12)2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38138084

RESUMO

The viral agent SARS-CoV-2 clearly affects several organ systems, including the cardiovascular system. Angiopoietins are involved in vascular integrity and angiogenesis. Angiopoietin-1 (Ang1) promotes vessel stabilization, while angiopoietin-2 (Ang2), which is usually expressed at low levels, is significantly elevated in inflammatory and angiogenic conditions. Interleukin-6 (IL-6) is known to induce defective angiogenesis via the activation of the Ang2 pathway. Vasculitis and vasculopathy are some of the defining features of moderate to severe COVID-19-associated systemic disease. We investigated the serum levels of angiopoietins, as well as interleukin-6 levels and anti-SARS-CoV2 IgG titers, in hospitalized COVID-19 patients across disease severity and healthy controls. Ang2 levels were elevated in COVID-19 patients across all severity compared to healthy controls, while Ang1 levels were decreased. The patients with adverse outcomes (death and/or prolonged hospitalization) had relatively lower and stable Ang1 levels but continuously elevated Ang2 levels, while those who had no adverse outcomes had increasing levels of both Ang1 and Ang2, followed by a decrease in both. These results suggest that the dynamic levels of Ang1 and Ang2 during the clinical course may predict adverse outcomes in COVID-19 patients. Ang1 seems to play an important role in controlling Ang2-related inflammatory mechanisms in COVID-19 patients. IL-6 and anti-SARS-CoV2 spike protein IgG levels were significantly elevated in patients with severe disease. Our findings represent an informative pilot assessment into the role of the angiopoietin signaling pathway in the inflammatory response in COVID-19.

4.
Science ; 382(6674): 1042-1050, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37972196

RESUMO

Ephrin type-A receptor 2 (EphA2) is a receptor tyrosine kinase that initiates both ligand-dependent tumor-suppressive and ligand-independent oncogenic signaling. We used time-resolved, live-cell fluorescence spectroscopy to show that the ligand-free EphA2 assembles into multimers driven by two types of intermolecular interactions in the ectodomain. The first type entails extended symmetric interactions required for ligand-induced receptor clustering and tumor-suppressive signaling that inhibits activity of the oncogenic extracellular signal-regulated kinase (ERK) and protein kinase B (AKT) protein kinases and suppresses cell migration. The second type is an asymmetric interaction between the amino terminus and the membrane proximal domain of the neighboring receptors, which supports oncogenic signaling and promotes migration in vitro and tumor invasiveness in vivo. Our results identify the molecular interactions that drive the formation of the EphA2 multimeric signaling clusters and reveal the pivotal role of EphA2 assembly in dictating its opposing functions in oncogenesis.


Assuntos
Multimerização Proteica , Receptor EphA2 , Proteínas Supressoras de Tumor , Humanos , Ligantes , Invasividade Neoplásica , Fosforilação , Receptor EphA2/química , Receptor EphA2/metabolismo , Transdução de Sinais , Espectrometria de Fluorescência , Proteínas Supressoras de Tumor/química , Proteínas Supressoras de Tumor/metabolismo
5.
Nanomaterials (Basel) ; 13(17)2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37686915

RESUMO

OEMT is an existing optimizing envelope method for thin-film characterization that uses only one transmittance spectrum, T(λ), of the film deposited on the substrate. OEMT computes the optimized values of the average thickness, d¯, and the thickness non-uniformity, Δd, employing variables for the external smoothing of T(λ), the slit width correction, and the optimized wavelength intervals for the computation of d¯ and Δd, and taking into account both the finite size and absorption of the substrate. Our group had achieved record low relative errors, <0.1%, in d¯ of thin semiconductor films via OEMT, whereas the high accuracy of d¯ and Δd allow for the accurate computation of the complex refractive index, N˙(λ), of the film. In this paper is a proposed envelope method, named OEMR, for the characterization of thin dielectric or semiconductor films using only one quasi-normal incidence UV/Vis/NIR reflectance spectrum, R(λ), of the film on the substrate. The features of OEMR are similar to the described above features of OEMT. OEMR and several popular dispersion models are employed for the characterization of two a-Si films, only from R(λ), with computed d¯ = 674.3 nm and Δd = 11.5 nm for the thinner film. It is demonstrated that the most accurate characterizations of these films over the measured spectrum are based on OEMR.

6.
Virchows Arch ; 483(4): 541-548, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37401932

RESUMO

Branchioma (previously called ectopic hamartomatous thymoma, branchial anlage mixed tumor, or thymic anlage tumor) is a rare lower neck lesion with an adult male predominance and an uncertain histogenesis. Except for 4 cases, all branchiomas described in the literature were benign. Recently, HRAS mutation was detected in one case, but still little is known about the molecular genetic background of this rare entity. We herein report the histological, immunohistochemical, and molecular genetic analysis of a branchioma with a nested/organoid (neuroendocrine-like) morphology in a 78-year-old man. Histology revealed classical branchioma areas merging with nested/organoid cellular component lacking conventional features of malignancy. Immunohistochemistry was positive for high-molecular-weight cytokeratins. CD34 was expressed in the spindle cell component. Moreover, the tumor cells showed near-complete loss of retinoblastoma (RB1) expression (<1% of cells positive). All neuroendocrine markers (synaptophysin, chromogranin, and INSM1) were negative. Next-generation sequencing (TSO500 Panel) revealed 5 pathogenic/likely pathogenic mutations including 1 mutation in KRAS and 2 different mutations in each of MSH6 and PTEN. FISH and DNA sequencing were negative for RB1 gene alterations. To our knowledge, this is the first report of a branchioma showing misleading nested/organoid morphology and the first report on Rb1 immunodeficiency in this entity, in addition to multiple gene mutations revealed by NGS.


Assuntos
Branquioma , Neoplasias da Retina , Retinoblastoma , Neoplasias de Tecidos Moles , Idoso , Feminino , Humanos , Masculino , Branquioma/patologia , Organoides/patologia , Proteínas Repressoras , Retinoblastoma/genética , Retinoblastoma/patologia
7.
Folia Med (Plovdiv) ; 65(2): 336-342, 2023 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-37144324

RESUMO

We present two case reports of cardiac echinococcosis. Case 1 was a 33-year-old woman with hepatic and cardiac echinococcosis. The parasitic cyst was located intramyocardially in the free wall of the left ventricle leading to cranial dislocation of the left circumflex coronary artery (LCx). The patient was successfully operated. Case 2 was a 28-year-old woman with hepatic and cardiac echinococcosis. The parasitic cyst was located in the left ventricular myocardium in the area of the apex and manifested clinically as paroxysms of ventricular tachycardia. The ultrasound study showed a 3.2×2.8 cm cyst dislocating the papillary muscles and causing moderate mitral regurgitation.Bulgaria ranks first in the European Union in terms of the number of echinococcosis patients. Although cardiac involvement is uncommon, occurring in only 0.5%-2% of cases, it can cause a wide range of clinical symptoms. Multimodal imaging is a key step in the management of patients with cardiac involvement.


Assuntos
Equinococose , Insuficiência da Valva Mitral , Feminino , Humanos , Adulto , Equinococose/diagnóstico por imagem , Equinococose/cirurgia , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/cirurgia , Ecocardiografia , Tomografia Computadorizada por Raios X
8.
Clin Cancer Res ; 29(14): 2686-2701, 2023 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-36976175

RESUMO

PURPOSE: Accumulating analyses of pro-oncogenic molecular mechanisms triggered a rapid development of targeted cancer therapies. Although many of these treatments produce impressive initial responses, eventual resistance onset is practically unavoidable. One of the main approaches for preventing this refractory condition relies on the implementation of combination therapies. This includes dual-specificity reagents that affect both of their targets with a high level of selectivity. Unfortunately, selection of target combinations for these treatments is often confounded by limitations in our understanding of tumor biology. Here, we describe and validate a multipronged unbiased strategy for predicting optimal co-targets for bispecific therapeutics. EXPERIMENTAL DESIGN: Our strategy integrates ex vivo genome-wide loss-of-function screening, BioID interactome profiling, and gene expression analysis of patient data to identify the best fit co-targets. Final validation of selected target combinations is done in tumorsphere cultures and xenograft models. RESULTS: Integration of our experimental approaches unambiguously pointed toward EGFR and EPHA2 tyrosine kinase receptors as molecules of choice for co-targeting in multiple tumor types. Following this lead, we generated a human bispecific anti-EGFR/EPHA2 antibody that, as predicted, very effectively suppresses tumor growth compared with its prototype anti-EGFR therapeutic antibody, cetuximab. CONCLUSIONS: Our work not only presents a new bispecific antibody with a high potential for being developed into clinically relevant biologics, but more importantly, successfully validates a novel unbiased strategy for selecting biologically optimal target combinations. This is of a significant translational relevance, as such multifaceted unbiased approaches are likely to augment the development of effective combination therapies for cancer treatment. See related commentary by Kumar, p. 2570.


Assuntos
Anticorpos Biespecíficos , Neoplasias , Humanos , Receptores ErbB/metabolismo , Linhagem Celular Tumoral , Cetuximab/farmacologia , Anticorpos Biespecíficos/farmacologia , Anticorpos Biespecíficos/uso terapêutico , Anticorpos Biespecíficos/imunologia , Neoplasias/tratamento farmacológico , Neoplasias/genética
9.
Biomed Pharmacother ; 161: 114494, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36917886

RESUMO

Metastasis and chemoresistance in colorectal cancer are mediated by certain poorly differentiated cancer cells, known as cancer stem cells, that are maintained by Notch downstream signaling initiated upon Notch cleavage by the metalloprotease ADAM10. It has been shown that ADAM10 overexpression correlates with aberrant signaling from Notch, erbBs, and other receptors, as well as a more aggressive metastatic phenotype, in a range of cancers including colon, gastric, prostate, breast, ovarian, uterine, and leukemia. ADAM10 inhibition, therefore, stands out as an important and new approach to deter the progression of advanced CRC. For targeting the ADAM10 substrate-binding region, which is located outside of the catalytic domain of the protease, we generated a human anti-ADAM10 monoclonal antibody named 1H5. Structural and functional characterization of 1H5 reveals that it binds to the substrate-binding cysteine-rich domain and recognizes an activated ADAM10 conformation present on tumor cells. The mAb inhibits Notch cleavage and proliferation of colon cancer cell lines in vitro and in mouse models. Consistent with its binding to activated ADAM10, the mAb augments the catalytic activity of ADAM10 towards small peptide substrates in vitro. Most importantly, in a mouse model of colon cancer, when administered in combination with the therapeutic agent Irinotecan, 1H5 causes highly effective tumor growth inhibition without any discernible toxicity effects. Our singular approach to target the ADAM10 substrate-binding region with therapeutic antibodies could overcome the shortcomings of previous intervention strategies of targeting the protease active site with small molecule inhibitors that exhibit musculoskeletal toxicity.


Assuntos
Neoplasias do Colo , Neoplasias Colorretais , Masculino , Camundongos , Animais , Humanos , Anticorpos Monoclonais/farmacologia , Proteínas de Membrana/metabolismo , Proteína ADAM10/metabolismo , Neoplasias Colorretais/tratamento farmacológico , Secretases da Proteína Precursora do Amiloide/metabolismo
10.
Neoplasma ; 70(6): 796-803, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38247336

RESUMO

The aim of this study was to investigate the prognostic significance of membranous ß-catenin and cytoplasmic ß-catenin expression in pancreatic cancer patients (pts). One hundred pts with histologically verified exocrine pancreatic ductal adenocarcinoma were retrospectively studied. The membranous ß-catenin, cytoplasmic ß-catenin, and cell nucleus ß-catenin expression were immunohistochemically evaluated. The expression of membranous ß-catenin was <5% in none of the pts, 5-25% in one patient, 26-50% in 2 pts, 51-75% in 14 pts, and >75% in 81 pts. The expression of cytoplasmic ß-catenin was <5% in 34 pts, 5-25% in 42 pts, 26-50% in 18 pts, 51-75% in 3 pts, and >75% in one patient. The expression of ß-catenin in the cell nucleus was negative in all pts. At the time of the last follow-up, 21 pts were alive and 79 pts had died. Median OS was 1.3 (0.4-2.3) years in pts with membranous ß-catenin expression ≤75% and 1.7 (1.3-2.1) years in pts with membranous ß-catenin expression >75% (p=0.045). Median OS was (1.3-2.0) 1.6 years in pts with cytoplasmic ß-catenin expression ≤25% and 0.9 (0.5-1.2) years in pts with cytoplasmic ß-catenin expression >25% (p=0.040). In the univariate Cox proportional hazard models HR (95% CI) was 0.556 (0.311-0.995) in pts with membranous ß-catenin expression >75% (p=0.048) and 2.200 (1.216-3.980) in pts with cytoplasmic ß-catenin expression >25% (p=0.009). The present results indicate a favorable prognostic significance of membranous ß-catenin expression in pancreatic cancer.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , beta Catenina , Humanos , beta Catenina/genética , beta Catenina/metabolismo , Carcinoma Ductal Pancreático/diagnóstico , Carcinoma Ductal Pancreático/genética , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/genética , Prognóstico , Estudos Retrospectivos
11.
Cancers (Basel) ; 14(13)2022 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-35804938

RESUMO

ADAM10 is a transmembrane metalloprotease that sheds a variety of cell surface proteins, including receptors and ligands that regulate a range of developmental processes which re-emerge during tumour development. While ADAM10 is ubiquitously expressed, its activity is normally tightly regulated, but becomes deregulated in tumours. We previously reported the generation of a monoclonal antibody, 8C7, which preferentially recognises an active form of ADAM10 in human and mouse tumours. We now report our investigation of the mechanism of this specificity, and the preferential targeting of 8C7 to human tumour cell xenografts in mice. We also report the development of novel 8C7 antibody-drug conjugates that preferentially kill cells displaying the 8C7 epitope, and that can inhibit tumour growth in mice. This study provides the first demonstration that antibody-drug conjugates targeting an active conformer of ADAM10, a widely expressed transmembrane metalloprotease, enable tumour-selective targeting and inhibition.

13.
Transl Oncol ; 15(1): 101265, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34768098

RESUMO

ADAM17 is upregulated in many cancers and in turn activates signaling pathways, including EGFR/ErbB, as well as those underlying resistance to targeted anti-EGFR therapies. Due to its central role in oncogenic pathways and drug resistance mechanisms, specific and efficacious monoclonal antibodies against ADAM17 could be useful for a broad patient population with solid tumors. Hence, we describe here an inhibitory anti-ADAM17 monoclonal antibody, named D8P1C1, that preferentially recognizes ADAM17 on cancer cells. D8P1C1 inhibits the catalytic activity of ADAM17 in a fluorescence-based peptide cleavage assay, as well as the proliferation of a range of cancer cell lines, including breast, ovarian, glioma, colon and the lung adenocarcinoma. In mouse models of triple-negative breast cancer and ovarian cancer, treatment with the mAb results in 78% and 45% tumor growth inhibition, respectively. Negative staining electron microscopy analysis of the ADAM17 ectodomain in complex with D8P1C1 reveals that the mAb binds the ADAM17 protease domain, consistent with its ability to inhibit the ADAM17 catalytic activity. Collectively, our results demonstrate the therapeutic potential of the D8P1C1 mAb to treat solid tumors.

14.
Kardiochir Torakochirurgia Pol ; 19(4): 199-204, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36643344

RESUMO

Introduction: Myocardial protection in reoperative cardiac surgery is extremely difficult in patients with previous coronary surgery and a working LAD-LIMA graft. We use the method of percutaneous angiographic balloon left internal mammary artery (LIMA) occlusion and cardioplegic arrest. Aim: To compare the data of patients with angiographic balloon LIMA-occlusion and those without occlusion in operations related to prosthetic valve endocarditis (PVE), and determine the degree of safety and benefits of the method. Material and methods: A total of 20 patients undergoing surgery for PVE with a patent LIMA-LAD graft were analyzed retrospectively. We divided the patients into 2 groups: group A - patients with LIMA occlusion; and group B - patients without LIMA occlusion. The pre-, intra- and postoperative results were compared and the degree of safety and benefits of the application of the method were studied. Results: 80% of patients in group A needed only dopamine infusion and 20% needed the addition of a second catecholamine at the end of CPB. In group B, the need for double catecholamine maintenance was noted in 50% of patients. The need for implantation of an intra-aortic balloon pump due to refractory heart failure was registered in 10% of patients in group A and in 20% of patients in group B. In terms of survival, mortality in the group with LIMA occlusion was 0%, while in the group without LIMA occlusion it was 20%. Conclusions: Our observations suggest that angiographic balloon LIMA occlusion is a reliable, easily applicable and relatively safe technique that improves the surgical results.

15.
Int J Mol Sci ; 22(19)2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34638814

RESUMO

The Eph receptor tyrosine kinases and their ephrin ligands direct axon pathfinding and neuronal cell migration, as well as mediate many other cell-cell communication events. Their dysfunctional signaling has been shown to lead to various diseases, including cancer. The Ephs and ephrins both localize to the plasma membrane and, upon cell-cell contact, form extensive signaling assemblies at the contact sites. The Ephs and the ephrins are divided into A and B subclasses based on their sequence conservation and affinities for each other. The molecular details of Eph-ephrin recognition have been previously revealed and it has been documented that ephrin binding induces higher-order Eph assemblies, which are essential for full biological activity, via multiple, distinct Eph-Eph interfaces. One Eph-Eph interface type is characterized by a homotypic, head-to-tail interaction between the ligand-binding and the fibronectin domains of two adjacent Eph molecules. While the previous Eph ectodomain structural studies were focused on A class receptors, we now report the crystal structure of the full ectodomain of EphB2, revealing distinct and unique head-to-tail receptor-receptor interactions. The EphB2 structure and structure-based mutagenesis document that EphB2 uses the head-to-tail interactions as a novel autoinhibitory control mechanism for regulating downstream signaling and that these interactions can be modulated by posttranslational modifications.


Assuntos
Receptor EphB2/química , Receptor EphB2/metabolismo , Transdução de Sinais , Animais , Células HEK293 , Humanos , Camundongos , Domínios Proteicos , Receptor EphB2/genética , Relação Estrutura-Atividade
16.
Heliyon ; 7(6): e07200, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34095559

RESUMO

More than 3.5 million people have died globally from COVID-19, yet an effective therapy is not available. It is, therefore, important to understand the signaling pathways that mediate disease progression in order to identify new molecular targets for therapeutic development. Here, we report that the blood serum levels of ephrin-A1 and the sheddase ADAM12 were significantly elevated in COVID-19 patients treated at SUNY Downstate Hospital of Brooklyn, New York. Both ephrin-A1 and ADAM12 are known to be involved in inflammation and regulate endothelial cell permeability, thus providing a gateway to lung injury. The clinical outcome correlated with the ephrin-A1 and ADAM12 serum levels during the first week of hospitalization. In contrast, the serum levels of TNFα were elevated in only a small subset of the patients, and these same patients also had highly elevated levels of the sheddase ADAM17. These data indicate that ephrin-A1-mediated inflammatory signaling may contribute to COVID-19 disease progression more so than TNFα-mediated inflammatory signaling. They also support the notion that, in COVID-19 inflammation, ADAM12 sheds ephrin-A1, while ADAM17 sheds TNFα. Furthermore, the results suggest that elevated serum levels and activity of cytokines, such as TNFα, and other secreted inflammatory molecules, such as ephrin-A1, are not simply due to overexpression, but also to upregulation of sheddases that release them into the blood circulation. Our results identify ephrin-A1, ADAM12, and other molecules in the ephrin-A1 signaling pathway as potential pharmacological targets for treating COVID-19 inflammation.

17.
PLoS One ; 16(3): e0247335, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33770085

RESUMO

Eph receptors are the largest group amongst the receptor tyrosine kinases and are divided into two subgroups, A and B, based on ligand binding specificities and sequence conservation. Through ligand-induced and ligand-independent activities, Ephs play central roles in diverse biological processes, including embryo development, regulation of neuronal signaling, immune responses, vasculogenesis, as well as tumor initiation, progression, and metastasis. The Eph extracellular regions (ECDs) are constituted of multiple domains, and previous structural studies of the A class receptors revealed how they interact with ephrin ligands and simultaneously mediate Eph-Eph clustering necessary for biological activity. Specifically, EphA structures highlighted a model, where clustering of ligand-bound receptors relies on two distinct receptor/receptor interfaces. Interestingly, most unliganded A class receptors also form an additional, third interface, between the ligand binding domain (LBD) and the fibronectin III domain (FN3) of neighboring molecules. Structures of B-class Eph ECDs, on the other hand, have never been reported. To further our understanding of Eph receptor function, we crystallized the EphB6-ECD and determined its three-dimensional structure using X-ray crystallography. EphB6 has important functions in both normal physiology and human malignancies and is especially interesting because this atypical receptor innately lacks kinase activity and our understanding of the mechanism of action is still incomplete. Our structural data reveals the overall EphB6-ECD architecture and shows EphB6-LBD/FN3 interactions similar to those observed for the unliganded A class receptors, suggesting that these unusual interactions are of general importance to the Eph group. We also observe unique structural features, which likely reflect the atypical signaling properties of EphB6, namely the need of co-receptor(s) for this kinase-inactive Eph. These findings provide new valuable information on the structural organization and mechanism of action of the B-class Ephs, and specifically EphB6, which in the future will assist in identifying clinically relevant targets for cancer therapy.


Assuntos
Receptor EphB6/ultraestrutura , Receptores da Família Eph/ultraestrutura , Linhagem Celular , Cristalografia por Raios X/métodos , Efrinas/metabolismo , Fibronectinas/metabolismo , Humanos , Ligantes , Fosforilação , Ligação Proteica/fisiologia , Domínios Proteicos/fisiologia , Receptor EphA1/metabolismo , Receptor EphA1/ultraestrutura , Receptor EphB6/metabolismo , Receptores da Família Eph/metabolismo , Transdução de Sinais
18.
Hum Immunol ; 82(4): 255-263, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33640208

RESUMO

Early in the SARS-CoV-2 pandemic, convalescent plasma (CP) therapy was proposed as a treatment for severely ill patients. We conducted a CP treatment protocol under the Mayo Clinic Extended Access Program at University Hospital Brooklyn (UHB). Potential donors were screened with a lateral flow assay (LFA) for IgM and IgG antibodies against the SARS-CoV-2 S1 receptor-binding domain (RBD). Volunteers that were LFA positive were tested with an ELISA to measure IgG titers against the RBD. Subjects with titers of at least 1:1024 were selected to donate. Most donors with positive LFA had acceptable titers and were eligible to donate. Out of 171 volunteers, only 65 tested positive in the LFA (38.0%), and 55 (32.2%) had titers of at least 1:1024. Before our donation program started, 31 CP units were procured from the New York Blood Center (NYBC). Among the 31 CP units that were obtained from the NYBC, 25 units (80.6%) were positive in the LFA but only 12 units (38.7%) had titers of at least 1:1024. CP was administered to 28 hospitalized COVID-19 patients. Patients who received low titer CP, high titer CP and patients who did not receive CP were followed for 45 days after presentation. Severe adverse events were not associated with CP transfusion. Death was a less frequent outcome for patients that received high titer CP (>1:1024) 38.6% mortality, than patients that received low titer CP (≤1:1024) 77.8% mortality.


Assuntos
Anticorpos Antivirais/uso terapêutico , COVID-19/terapia , SARS-CoV-2/imunologia , Adulto , Idoso , Anticorpos Antivirais/imunologia , Doadores de Sangue , Seleção do Doador , Feminino , Humanos , Imunização Passiva/métodos , Imunoglobulina G/sangue , Imunoglobulina G/uso terapêutico , Imunoglobulina M/sangue , Imunoglobulina M/uso terapêutico , Masculino , Pessoa de Meia-Idade , Plasma/imunologia , Estudos Retrospectivos , Soroterapia para COVID-19
19.
J BUON ; 24(4): 1644-1651, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31646820

RESUMO

PURPOSE: The aim of this study was to investigate the potential association and combined prognostic significance of the frequency of primary cilia (PC), programmed cell death protein-1 receptor (PD1) and CD8+ tumor infiltrating lymphocytes (TIL) in patients with clear cell renal cancer (ccRCC). METHODS: The frequency of PC, PD1 expression and the frequency of intratumoral CD8+ TIL were evaluated in 104 ccRCC patients. RESULTS: The median frequency of PC was 0.003. The expression of PD1+ cells were <5% in 52 patients, 5-25% in 34 patients and 26-50% in 13 patients and >50% in 5 patients. Intratumoral CD8+ TIL were evaluable in all patients: negative in 1 patient, <25% in 63, 26-50% in 29 and >50% in 11 patients. Overall survival (OS) according to the frequency of PC was significantly shorter in patients with higher frequency (≥0.002) than in patients with lower frequency (<0.002) (p<0.001). Median OS was significantly shorter in patients with higher (25%) CD8+ TIL and higher (>25%) PD1+ expression than in patients with lower (<25%) expression (4.6 vs. 97. years, p=0.006 and 2.9 vs. 8.9 years, p=0.006, respectively). CONCLUSIONS: The present study provides the first data on the potential association and combined prognostic significance of frequency of PC, PD1+ cells and CD8+ TIL in patients with clear cell renal cancer.


Assuntos
Carcinoma de Células Renais/genética , Cílios/genética , Prognóstico , Receptor de Morte Celular Programada 1/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Linfócitos T CD8-Positivos/patologia , Carcinoma de Células Renais/patologia , Cílios/patologia , Intervalo Livre de Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Linfócitos do Interstício Tumoral/patologia , Masculino , Pessoa de Meia-Idade
20.
Cancer Lett ; 467: 50-57, 2019 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-31593799

RESUMO

ADAM proteases are multi domain transmembrane metalloproteases that cleave a range of cell surface proteins and activate signaling pathways implicated in tumor progression, including those mediated by Notch, EFGR, and the Eph receptors. Consequently, they have emerged as key therapeutic targets in the efforts to inhibit tumor initiation and progression. To that end, two main approaches have been taken to develop ADAM antagonists: (i) small molecule inhibitors, and (ii) monoclonal antibodies. In this mini-review we describe the distinct features of ADAM proteases, particularly of ADAM10 and ADAM17, their domain organization, conformational rearrangements, regulation, as well as their emerging importance as therapeutic targets in cancer. Further, we highlight an anti-ADAM10 monoclonal antibody that we have recently developed, which has shown significant promise in inhibiting Notch signaling and deterring growth of solid tumors in pre-clinical settings.


Assuntos
Proteínas ADAM/química , Proteínas ADAM/metabolismo , Neoplasias/metabolismo , Proteínas ADAM/antagonistas & inibidores , Proteína ADAM10/antagonistas & inibidores , Proteína ADAM10/química , Proteína ADAM10/metabolismo , Proteína ADAM17/química , Proteína ADAM17/metabolismo , Animais , Antineoplásicos Imunológicos/farmacologia , Antineoplásicos Imunológicos/uso terapêutico , Domínio Catalítico , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias/tratamento farmacológico , Conformação Proteica , Domínios Proteicos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...