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1.
Brain Pathol ; : e13265, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38705944

RESUMO

Gliomagenesis induces profound changes in the composition of the extracellular matrix (ECM) of the brain. In this study, we identified a cellular population responsible for the increased deposition of collagen I and fibronectin in glioblastoma. Elevated levels of the fibrillar proteins collagen I and fibronectin were associated with the expression of fibroblast activation protein (FAP), which is predominantly found in pericyte-like cells in glioblastoma. FAP+ pericyte-like cells were present in regions rich in collagen I and fibronectin in biopsy material and produced substantially more collagen I and fibronectin in vitro compared to other cell types found in the GBM microenvironment. Using mass spectrometry, we demonstrated that 3D matrices produced by FAP+ pericyte-like cells are rich in collagen I and fibronectin and contain several basement membrane proteins. This expression pattern differed markedly from glioma cells. Finally, we have shown that ECM produced by FAP+ pericyte-like cells enhances the migration of glioma cells including glioma stem-like cells, promotes their adhesion, and activates focal adhesion kinase (FAK) signaling. Taken together, our findings establish FAP+ pericyte-like cells as crucial producers of a complex ECM rich in collagen I and fibronectin, facilitating the dissemination of glioma cells through FAK activation.

2.
J Neurosurg ; : 1-12, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38552239

RESUMO

OBJECTIVE: The highly infiltrative growth of glioblastoma (GBM) makes distinction between the tumor and normal brain tissue challenging. Therefore, fluorescence-guided surgery is often used to improve visual identification of radiological tumor margins. The aim of this study was to evaluate the ability of recently developed molecularly targeted near-infrared (NIR) protease-activated probes to visualize GBM tissue and to compare the most promising candidate with the gold standard, 5-aminolevulinic acid (5-ALA). METHODS: Single-substrate probes 6QC-ICG and 6QC-Cy5 (cysteine cathepsin cleavable), double-substrate probes AG2-FNIR and AG2-Cy5 (cysteine cathepsin and caspase 3 cleavable), and 5-ALA were administered intravenously to mice with orthotopic tumors. Activation of the probes was also evaluated in cell cultures in vitro and in biopsy material from patients with GBM ex vivo. The tumor to normal brain tissue fluorescence ratio (TNR) was quantified in brain sections using preclinical and clinical visualization platforms, and in tissue homogenates and cell suspensions using spectrofluorimetry. Subcellular localization of the fluorophores was visualized by confocal microscopy. RESULTS: In vitro, the single-substrate probe 6QC-ICG was cleaved in glioma cells and macrophages, and the resulting fluorophore accumulated intracellularly. In experimental GBMs, both single- and double-substrate probes visualized tumor tissue, while in healthy brain tissue the signal was minimal. TNR was highest for 6QC-ICG and AG2-FNIR, but the signal intensity was higher for 6QC-ICG. Using xenograft and syngeneic mouse models, as well as human GBM biopsy material ex vivo, the authors confirmed the ability of 6QC-ICG to specifically visualize the glioma tissue using preclinical and clinical visualization platforms. Finally, a comparison with 5-ALA in animals coadministered with both compounds revealed a higher TNR for 6QC-ICG in experimental GBMs. CONCLUSIONS: The cysteine cathepsin-cleavable probe 6QC-ICG is activated by glioma cells and tumor-associated macrophages, leading to a high contrast between tumor and nontumorous brain tissue that is superior to that of the current standard, 5-ALA. In addition to a well-defined mechanism of action, protease-activated probes that use NIR fluorophores (e.g., indocyanine green) have the advantage of low absorption and scattering of the NIR light and lower tissue autofluorescence. These results suggest that 6QC-ICG has the potential to become the targeted agent in intraoperative detection of GBM tissue using fluorescence imaging.

3.
Biomark Res ; 12(1): 15, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38303021

RESUMO

Small noncoding RNAs play an important role in various disease states, including cancer. PIWI proteins, a subfamily of Argonaute proteins, and PIWI-interacting RNAs (piRNAs) were originally described as germline-specific molecules that inhibit the deleterious activity of transposable elements. However, several studies have suggested a role for the piRNA-PIWI axis in somatic cells, including somatic stem cells. Dysregulated expression of piRNAs and PIWI proteins in human tumors implies that, analogously to their roles in undifferentiated cells under physiological conditions, these molecules may be important for cancer stem cells and thus contribute to cancer progression. We provide an overview of piRNA biogenesis and critically review the evidence for the role of piRNA-PIWI axis in cancer stem cells. In addition, we examine the potential of piRNAs and PIWI proteins to become biomarkers in cancer.

4.
Bioorg Chem ; 141: 106816, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37716274

RESUMO

Pentamethinium indolium salts are promising fluorescence probes and anticancer agents with high mitochondrial selectivity. We synthesized two indolium pentamethinium salts: a cyclic form with quinoxaline directly incorporated in the pentamethinium chain (cPMS) and an open form with quinoxaline substitution in the γ-position (oPMS). To better understand their properties, we studied their interaction with mitochondrial phospholipids (cardiolipin and phosphatidylcholine) by spectroscopic methods (UV-Vis, fluorescence, and NMR spectroscopy). Both compounds displayed significant affinity for cardiolipin and phosphatidylcholine, which was associated with a strong change in their UV-Vis spectra. Nevertheless, we surprisingly observed that fluorescence properties of cPMS changed in complex with both cardiolipin and phosphatidylcholine, whereas those of oPMS only changed in complex with cardiolipin. Both salts, especially cPMS, display high usability in mitochondrial imaging and are cytotoxic for cancer cells. The above clearly indicates that conjugates of pentamethinium and quinoxaline group, especially cPMS, represent promising structural motifs for designing mitochondrial-specific agents.


Assuntos
Antineoplásicos , Cardiolipinas , Quinoxalinas/farmacologia , Sais , Antineoplásicos/farmacologia , Antineoplásicos/química , Fosfatidilcolinas
5.
Pathology ; 55(6): 806-817, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37419841

RESUMO

Brain metastases are a very common and serious complication of oncological diseases. Despite the vast progress in multimodality treatment, brain metastases significantly decrease the quality of life and prognosis of patients. Therefore, identifying new targets in the microenvironment of brain metastases is desirable. Fibroblast activation protein (FAP) is a transmembrane serine protease typically expressed in tumour-associated stromal cells. Due to its characteristic presence in the tumour microenvironment, FAP represents an attractive theranostic target in oncology. However, there is little information on FAP expression in brain metastases. In this study, we quantified FAP expression in samples of brain metastases of various primary origin and characterised FAP-expressing cells. We have shown that FAP expression is significantly higher in brain metastases in comparison to non-tumorous brain tissues, both at the protein and enzymatic activity levels. FAP immunopositivity was localised in regions rich in collagen and containing blood vessels. We have further shown that FAP is predominantly confined to stromal cells expressing markers typical of cancer-associated fibroblasts (CAFs). We have also observed FAP immunopositivity on tumour cells in a portion of brain metastases, mainly originating from melanoma, lung, breast, and renal cancer, and sarcoma. There were no significant differences in the quantity of FAP protein, enzymatic activity, and FAP+ stromal cells among brain metastasis samples of various origins, suggesting that there is no association of FAP expression and/or presence of FAP+ stromal cells with the histological type of brain metastases. In summary, we are the first to establish the expression of FAP and characterise FAP-expressing cells in the microenvironment of brain metastases. The frequent upregulation of FAP and its presence on both stromal and tumour cells support the use of FAP as a promising theranostic target in brain metastases.


Assuntos
Neoplasias Encefálicas , Carcinoma de Células Renais , Neoplasias Renais , Humanos , Proteínas de Membrana/metabolismo , Medicina de Precisão , Qualidade de Vida , Fibroblastos/patologia , Serina Endopeptidases/metabolismo , Carcinoma de Células Renais/patologia , Neoplasias Encefálicas/patologia , Neoplasias Renais/patologia , Microambiente Tumoral
6.
Pharmaceutics ; 14(8)2022 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-36015338

RESUMO

IL-6 signaling is involved in the pathogenesis of a number of serious diseases, including chronic inflammation and cancer. Targeting of IL-6 receptor (IL-6R) by small molecules is therefore an intensively studied strategy in cancer treatment. We describe the design, synthesis, and characteristics of two new bis-pentamethinium salts 5 and 6 (meta and para) bearing indole moieties. Molecular docking studies showed that both compounds have the potential to bind IL-6R (free energy of binding -9.5 and -8.1 kcal/mol). The interaction with IL-6R was confirmed using microscale thermophoresis analyses, which revealed that both compounds had strong affinity for the IL-6R (experimentally determined dissociation constants 26.5 ± 2.5 nM and 304 ± 27.6 nM, respectively). In addition, both compounds were cytotoxic for a broad spectrum of cancer cell lines in micromolar concentrations, most likely due to their accumulation in mitochondria and inhibition of mitochondrial respiration. In summary, the structure motif of bis-pentamethinium salts represents a promising starting point for the design of novel multitargeting compounds with the potential to inhibit IL-6 signaling and simultaneously target mitochondrial metabolism in cancer cells.

7.
Cancers (Basel) ; 14(9)2022 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-35565202

RESUMO

Dipeptidyl peptidase IV (DPP-IV, CD26) is frequently dysregulated in cancer and plays an important role in regulating multiple bioactive peptides with the potential to influence cancer progression and the recruitment of immune cells. Therefore, it represents a potential contributing factor to cancer pathogenesis and an attractive therapeutic target. Specific DPP-IV inhibitors (gliptins) are currently used in patients with type 2 diabetes mellitus to promote insulin secretion by prolonging the activity of the incretins glucagon-like peptide 1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP). Nevertheless, the modulation of the bioavailability and function of other DPP-IV substrates, including chemokines, raises the possibility that the use of these orally administered drugs with favorable side-effect profiles might be extended beyond the treatment of hyperglycemia. In this review, we critically examine the possible utilization of DPP-IV inhibition in cancer prevention and various aspects of cancer treatment and discuss the potential perils associated with the inhibition of DPP-IV in cancer. The current literature is summarized regarding the possible chemopreventive and cytotoxic effects of gliptins and their potential utility in modulating the anti-tumor immune response, enhancing hematopoietic stem cell transplantation, preventing acute graft-versus-host disease, and alleviating the side-effects of conventional anti-tumor treatments.

8.
Cancers (Basel) ; 13(13)2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34282761

RESUMO

Fibroblast activation protein (FAP) is a membrane-bound protease that is upregulated in a wide range of tumours and viewed as a marker of tumour-promoting stroma. Previously, we demonstrated increased FAP expression in glioblastomas and described its localisation in cancer and stromal cells. In this study, we show that FAP+ stromal cells are mostly localised in the vicinity of activated CD105+ endothelial cells and their quantity positively correlates with glioblastoma vascularisation. FAP+ mesenchymal cells derived from human glioblastomas are non-tumorigenic and mostly lack the cytogenetic aberrations characteristic of glioblastomas. Conditioned media from these cells induce angiogenic sprouting and chemotaxis of endothelial cells and promote migration and growth of glioma cells. In a chorioallantoic membrane assay, co-application of FAP+ mesenchymal cells with glioma cells was associated with enhanced abnormal angiogenesis, as evidenced by an increased number of erythrocytes in vessel-like structures and higher occurrence of haemorrhages. FAP+ mesenchymal cells express proangiogenic factors, but in comparison to normal pericytes exhibit decreased levels of antiangiogenic molecules and an increased Angiopoietin 2/1 ratio. Our results show that FAP+ mesenchymal cells promote angiogenesis and glioma cell migration and growth by paracrine communication and in this manner, they may thus contribute to glioblastoma progression.

9.
Int J Mol Sci ; 22(3)2021 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-33494271

RESUMO

The proline-specific serine protease fibroblast activation protein (FAP) can participate in the progression of malignant tumors and represents a potential diagnostic and therapeutic target. Recently, we demonstrated an increased expression of FAP in glioblastomas, particularly those of the mesenchymal subtype. Factors controlling FAP expression in glioblastomas are unknown, but evidence suggests that transforming growth factor beta (TGFbeta) can trigger mesenchymal changes in these tumors. Here, we investigated whether TGFbeta promotes FAP expression in transformed and stromal cells constituting the glioblastoma microenvironment. We found that both FAP and TGFbeta-1 are upregulated in glioblastomas and display a significant positive correlation. We detected TGFbeta-1 immunopositivity broadly in glioblastoma tissues, including tumor parenchyma regions in the immediate vicinity of FAP-immunopositive perivascular stromal cells. Wedemonstrate for the first time that TGFbeta-1 induces expression of FAP in non-stem glioma cells, pericytes, and glioblastoma-derived endothelial and FAP+ mesenchymal cells, but not in glioma stem-like cells. In glioma cells, this effect is mediated by the TGFbeta type I receptor and canonical Smad signaling and involves activation of FAP gene transcription. We further present evidence of FAP regulation by TGFbeta-1 secreted by glioma cells. Our results provide insight into the previously unrecognized regulation of FAP expression by autocrine and paracrine TGFbeta-1 signaling in a broad spectrum of cell types present in the glioblastoma microenvironment.


Assuntos
Endopeptidases/genética , Regulação Neoplásica da Expressão Gênica , Glioblastoma/etiologia , Glioblastoma/metabolismo , Proteínas de Membrana/genética , Fator de Crescimento Transformador beta1/metabolismo , Microambiente Tumoral/genética , Linhagem Celular Tumoral , Células Cultivadas , Endopeptidases/metabolismo , Imunofluorescência , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioblastoma/patologia , Humanos , Imuno-Histoquímica , Proteínas de Membrana/metabolismo , Fosforilação , Fator de Crescimento Transformador beta1/farmacologia , Microambiente Tumoral/efeitos dos fármacos
10.
Biochim Biophys Acta Proteins Proteom ; 1868(7): 140409, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32171757

RESUMO

Fibroblast activation protein (FAP) is a non-classical serine protease expressed predominantly in conditions accompanied by tissue remodeling, particularly cancer. Due to its plasma membrane localization, FAP represents a promising molecular target for tumor imaging and treatment. The unique enzymatic activity of FAP facilitates development of diagnostic and therapeutic tools based on molecular recognition of FAP by substrates and small-molecule inhibitors, in addition to conventional antibody-based strategies. In this review, we provide background on the pathophysiological role of FAP and discuss its potential for diagnostic and therapeutic applications. Furthermore, we present a detailed analysis of the structural patterns crucial for substrate and inhibitor recognition by the FAP active site and determinants of selectivity over the related proteases dipeptidyl peptidase IV and prolyl endopeptidase. We also review published data on targeting of the tumor microenvironment with FAP antibodies, FAP-targeted prodrugs, activity-based probes and small-molecule inhibitors. We describe use of a recently developed, selective FAP inhibitor with low-nanomolar potency in inhibitor-based targeting strategies including synthetic antibody mimetics based on hydrophilic polymers and inhibitor conjugates for PET imaging. In conclusion, recent advances in understanding of the molecular structure and function of FAP have significantly contributed to the development of several tools with potential for translation into clinical practice.


Assuntos
Fibroblastos/metabolismo , Gelatinases/metabolismo , Proteínas de Membrana/metabolismo , Serina Endopeptidases/metabolismo , Domínio Catalítico , Dipeptidil Peptidase 4/metabolismo , Endopeptidases , Gelatinases/química , Gelatinases/efeitos dos fármacos , Humanos , Proteínas de Membrana/química , Proteínas de Membrana/efeitos dos fármacos , Estrutura Molecular , Neoplasias/diagnóstico , Neoplasias/metabolismo , Neoplasias/terapia , Pró-Fármacos , Prolil Oligopeptidases , Serina Endopeptidases/química , Serina Endopeptidases/efeitos dos fármacos , Especificidade por Substrato , Microambiente Tumoral
12.
Clin Neuropharmacol ; 41(4): 111-115, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29901476

RESUMO

INTRODUCTION: Modafinil may affect autonomic functions in healthy subjects. The aim of the study was to assess the long-term modafinil administration influence on the cardiac autonomic reactivity to orthostatic load in patients with narcolepsy type 1. METHODS: In 15 patients (4 male; 11 female; median age, 47 years; range, 18-70 years) with narcolepsy type 1 treated with modafinil in daily dose of 100 to 300 mg, the short-term spectral analysis of heart rate variability (HRV) in supine-standing-supine test was performed before and after 72 hours of modafinil discontinuation. RESULTS: The sympathovagal reactivity to orthostatic load was not modified by modafinil treatment; nevertheless, the parasympathetic activity expressed by length of R-R interval and high-frequency component of HRV is reduced in supine position in patients taking modafinil. CONCLUSIONS: We conclude that long-term use of modafinil does not influence the cardiac autonomic reactivity to orthostatic load expressed by the HRV changes in supine-standing-supine test in narcolepsy type 1 patients, but the parasympathetic cardiac activity may be reduced in quiet supine position in patients with narcolepsy taking modafinil.


Assuntos
Sistema Nervoso Autônomo/efeitos dos fármacos , Compostos Benzidrílicos/uso terapêutico , Narcolepsia/tratamento farmacológico , Narcolepsia/fisiopatologia , Promotores da Vigília/uso terapêutico , Adolescente , Adulto , Idoso , Relação Dose-Resposta a Droga , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Modafinila , Postura/fisiologia , Respiração/efeitos dos fármacos , Adulto Jovem
13.
Front Biosci (Landmark Ed) ; 23(10): 1933-1968, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29772538

RESUMO

Fibroblast activation protein (FAP, seprase) is a serine protease with post-proline dipeptidyl peptidase and endopeptidase enzymatic activity. FAP is upregulated in several tumor types, while its expression in healthy adult tissues is scarce. FAP molecule itself and FAP+ stromal cells play an important although probably context-dependent and tumor type-specific pathogenetic role in tumor progression. We provide an overview of FAP expression under both physiological and pathological conditions with focus on human malignancies. We also review and critically analyze the results of studies which used various strategies for the therapeutic targeting of FAP including the use of low molecular weight inhibitors, FAP activated prodrugs, anti-FAP antibodies and their conjugates, FAP-CAR T cells, and FAP vaccines. A unique enzymatic activity and selective expression in tumor microenvironment make FAP a promising therapeutic target. A better understanding of its role in individual tumor types, careful selection of patients, and identification of suitable combinations with currently available anticancer treatments will be critical for a successful translation of preclinically tested approaches of FAP targeting into clinical setting.


Assuntos
Inibidores Enzimáticos/uso terapêutico , Gelatinases/antagonistas & inibidores , Proteínas de Membrana/antagonistas & inibidores , Terapia de Alvo Molecular/métodos , Neoplasias/tratamento farmacológico , Endopeptidases , Gelatinases/genética , Gelatinases/metabolismo , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/genética
14.
Sci Rep ; 8(1): 2836, 2018 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-29434344

RESUMO

Glioblastoma stem-like cells (GSCs) are critical for the aggressiveness and progression of glioblastoma (GBM) and contribute to its resistance to adjuvant treatment. MicroRNAs (miRNAs) are small, non-coding RNAs controlling gene expression at the post-transcriptional level, which are known to be important regulators of the stem-like features. Moreover, miRNAs have been previously proved to be promising diagnostic biomarkers in several cancers including GBM. Using global expression analysis of miRNAs in 10 paired in-vitro as well as in-vivo characterized primary GSC and non-stem glioblastoma cultures, we identified a miRNA signature associated with the stem-like phenotype in GBM. 51 most deregulated miRNAs classified the cell cultures into GSC and non-stem cell clusters and identified a subgroup of GSC cultures with more pronounced stem-cell characteristics. The importance of the identified miRNA signature was further supported by demonstrating that a Risk Score based on the expression of seven miRNAs overexpressed in GSC predicted overall survival in GBM patients in the TCGA dataset independently of the IDH1 status. In summary, we identified miRNAs differentially expressed in GSCs and described their association with GBM patient survival. We propose that these miRNAs participate on GSC features and could represent helpful prognostic markers and potential therapeutic targets in GBM.


Assuntos
Neoplasias Encefálicas/genética , Perfilação da Expressão Gênica/métodos , Glioblastoma/genética , MicroRNAs/genética , Células-Tronco Neoplásicas/química , Idoso , Animais , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Isocitrato Desidrogenase/genética , Masculino , Camundongos , Pessoa de Meia-Idade , Mutação , Transplante de Neoplasias , Nestina , Fatores de Transcrição SOXB1/genética , Análise de Sobrevida , Células Tumorais Cultivadas
15.
J Med Chem ; 60(20): 8385-8393, 2017 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-28953383

RESUMO

Proteases are directly involved in cancer pathogenesis. Expression of fibroblast activation protein (FAP) is upregulated in stromal fibroblasts in more than 90% of epithelial cancers and is associated with tumor progression. FAP expression is minimal or absent in most normal adult tissues, suggesting its promise as a target for the diagnosis or treatment of various cancers. Here, we report preparation of a polymer conjugate (an iBody) containing a FAP-specific inhibitor as the targeting ligand. The iBody inhibits both human and mouse FAP with low nanomolar inhibition constants but does not inhibit close FAP homologues dipeptidyl peptidase IV, dipeptidyl peptidase 9, and prolyl oligopeptidase. We demonstrate the applicability of this iBody for the isolation of FAP from cell lysates and blood serum as well as for its detection by ELISA, Western blot, flow cytometry, and confocal microscopy. Our results show the iBody is a useful tool for FAP targeting in vitro and potentially also for specific anticancer drug delivery.


Assuntos
Gelatinases/antagonistas & inibidores , Proteínas de Membrana/antagonistas & inibidores , Polímeros/química , Animais , Western Blotting , Linhagem Celular Tumoral , Endopeptidases , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Gelatinases/química , Humanos , Proteínas de Membrana/química , Camundongos , Microscopia Confocal , Serina Endopeptidases/química , Espectrometria de Massas por Ionização por Electrospray
16.
Biochem Biophys Res Commun ; 491(1): 126-133, 2017 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-28711492

RESUMO

Human tumor xenografts in mice together with the species-specific analysis of expressed genes allow to study the molecular processes driving tumor growth and progression in vivo and help to develop and evaluate anticancer therapies. In the present work, we designed and validated species-specific real-time RT-PCR assays for discrimination and quantitation of expression of human and mouse transcripts in cancer and stromal cells including dipeptidyl peptidase (DPP) 4, DPP8, DPP9, fibroblast activation protein (FAP) and CXC chemokine receptor 4 in mixed human-mouse biological samples. Using single species RNA samples and mixed human-mouse RNA samples, we formulated and characterized two-step real-time RT-PCR assays to quantitate expression of the indicated transcripts and described analytical performance of the assays. We also demonstrated the applicability of these assays for species-specific quantitation of transcriptional expression of mouse stromal cell genes including Dpp4, Dpp8, Dpp9, Fap and Cxcr4 in mixed human-mouse RNA samples from human glioma cell-derived tumor xenografts growing in mouse brain.


Assuntos
Neoplasias Encefálicas/metabolismo , Encéfalo/metabolismo , Dipeptidil Peptidases e Tripeptidil Peptidases/metabolismo , Regulação Neoplásica da Expressão Gênica , Glioma/metabolismo , Receptores CXCR4/metabolismo , Células Estromais/metabolismo , Animais , Linhagem Celular Tumoral , Perfilação da Expressão Gênica , Humanos , Camundongos , Proteoma/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Especificidade da Espécie
17.
Eur J Gastroenterol Hepatol ; 29(8): 885-891, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28471824

RESUMO

Sporadic pancreatic cancer amounts to ∼90% of all pancreatic cancers. It is a gloomy depressive disease and the most recalcitrant malignancy, with a very low 5-year survival (3-6%). At present, diagnostic methods are commonly applied, as used half a century ago, after the appearance of local and systemic symptoms (abdominal and back pain, cholestasis, painless jaundice, fatigue, anorexia, weight loss, anemia, peripheral phlebitis, and cachexia). Unfortunately, these symptoms are harbingers of an advanced disease. The subsequent imaging methods may offer additional information on the location, size, and morphology of the lesion, but they do not influence the prognosis. Radical surgery may be offered to 15-20% of patients. The relapses after surgery are frequent and chemotherapy may be palliative. Preventive programs represent the only possibility of improvement. We propose the first multistep and multidisciplinary preventive program for early detection of sporadic pancreatic cancer for the differential identification of average-risk patients who probably have the disease from those who do not.


Assuntos
Carcinoma Ductal Pancreático/diagnóstico , Detecção Precoce de Câncer , Neoplasias Pancreáticas/diagnóstico , Carcinoma Ductal Pancreático/mortalidade , Carcinoma Ductal Pancreático/terapia , Humanos , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/terapia , Valor Preditivo dos Testes , Prognóstico , Medição de Risco , Fatores de Risco , Fatores de Tempo
18.
Artigo em Inglês | MEDLINE | ID: mdl-28452380

RESUMO

BACKGROUND AND AIMS: Proteolytic enzymes contribute to the progression of various cancers. We previously reported increased expression of the proline specific peptidases dipeptidyl peptidase-IV (DPP-IV) and its closest paralogue fibroblast activation protein (FAP) in human glioblastomas. Here we analyze the molecular heterogeneity of DPP-IV and FAP in glioblastomas. METHODS: ELISA, isoelectric focusing, 1D and 2D electrophoresis followed by WB or enzyme overlay assay were utilized to analyze DPP-IV and FAP isoforms. Cell fractionation using a Percoll gradient and deglycosylation with PNGase F were performed to analyze the possible basis of DPP-IV and FAP microheterogeneity. RESULTS: Molecular forms of DPP-IV with an estimated molecular weight of 140-160 kDa and a pI predominantly 5.8 were detected in human glioblastoma; in some tumors additional isoforms with a more acidic (3.5-5.5) as well as alkaline (8.1) pI were revealed. Using 2D electrophoresis, two to three molecular forms of FAP with an alkaline (7.0-8.5) pI and an estimated MW of 120-140 kDa were identified in glioblastoma tissues. In glioma cell lines in vitro, several isoforms of both enzymes were expressed, however the alkalic forms present in glioblastoma tissues were not detected. Removal of N-linked oligosaccharides decreased the estimated molecular weight of both enzymes; the overall pattern of molecular forms nevertheless remained unchanged. CONCLUSION: Several isoforms of DPP-IV and FAP are present in glioblastoma tissue. The absence of alkaline isoforms of both enzymes in glioma cell lines however suggests that isoforms from other, most likely stromal, cell types contribute to the overall pattern seen in glioblastoma tissues.


Assuntos
Encéfalo/enzimologia , Dipeptidil Peptidase 4/fisiologia , Gelatinases/fisiologia , Glioblastoma/enzimologia , Proteínas de Membrana/fisiologia , Serina Endopeptidases/fisiologia , Encéfalo/patologia , Fracionamento Celular , Eletroforese , Endopeptidases , Estabilidade Enzimática , Ensaio de Imunoadsorção Enzimática , Heterogeneidade Genética , Humanos , Imuno-Histoquímica , Focalização Isoelétrica , Células Tumorais Cultivadas
19.
Eur J Gastroenterol Hepatol ; 29(3): e13-e18, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28009716

RESUMO

Pancreatic cancer (PC) behaves very differently in comparison with other malignancies. Its incidence has been increasing continuously; mortality has not decreased, the diagnosis is frequently late, radical surgery is performed only in 15-20% of patients, and chemotherapy is only palliative. PC occurs in three different forms. Sporadic PC accounts for 90% of all PCs. Its most frequent form is the pancreatic ductal adenocarcinoma. The remaining 10% constitute two minority groups: familial PC (7%) and PC as a manifestation of a genetic cancer syndrome (3%). PCs are preceded by a precancerous lesion (precursor). At present, six different precursors are known. They have different histomorphological characteristics and malignant potential. The recognition and correct interpretation of individual precursors influences adequate clinical decision-making. The publication surveys the present knowledge of individual precursors and their role in the early pancreatic carcinogenesis.


Assuntos
Carcinoma Ductal Pancreático/patologia , Transformação Celular Neoplásica/patologia , Neoplasias Pancreáticas/patologia , Lesões Pré-Cancerosas/patologia , Idoso , Animais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/terapia , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Detecção Precoce de Câncer , Epigênese Genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/terapia , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/metabolismo , Lesões Pré-Cancerosas/terapia , Prognóstico , Fatores de Risco , Transdução de Sinais
20.
Pancreatology ; 17(1): 89-94, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28027898

RESUMO

BACKGROUND: The changes in gastrointestinal hormones associated with pancreatic ductal adenocarcinoma (PDAC) in patients with impaired glucoregulation have yet to be evaluated. The aim of this study was to determine plasma concentrations of selected gastrointestinal hormones in PDAC patients with and without diabetes and to compare them with levels found in Type 2 diabetic patients without cancer. METHODS: In this study we examined plasma concentrations of glucose-dependent insulinotropic peptide (GIP), glucagon-like peptide 1 (GLP-1), pancreatic polypeptide (PP), peptide YY (PYY) and neuropeptide Y (NPY), and cytokines leptin and adiponectin in 94 patients with histologically confirmed PDAC. Thirty-nine patients with Type 2 diabetes without PDAC and 29 healthy individuals with no evidence of acute or chronic diseases were examined as controls. RESULTS: Significantly lower plasma concentrations of GIP were found in PDAC patients with new-onset diabetes/prediabetes (n = 76), or in those with normal glucose regulation (n = 18), compared to patients with Type 2 diabetes without PDAC and controls (15.5 (3.7-64.5) or 6.5 (1.7-24.5) vs. 39.8 (15.1-104.7) and 28.8 (7.4-112.2) ng/L, p < 0.001); the same relationship was observed for PP (38.9 (10.2-147.9) or 28.1 (7.9-100.0) vs 89.1 (38.0-208.9) and 75.8 (30.1-190.6) ng/L, p < 0.01), respectively. The lowest levels of GIP and PP concentrations were found in PDAC patients with new-onset diabetes/prediabetes and weight loss > 2 kg (p < 0.001). CONCLUSIONS: We conclude that GIP and PP plasma concentrations are lower in pancreatic cancer irrespective of the degree of glucose intolerance as compared to Type 2 diabetic patients and healthy controls. In new onset diabetes especially if associated with weight loss, these changes may represent a new clue for the diagnosis of PDAC.


Assuntos
Glicemia/metabolismo , Carcinoma Ductal Pancreático/sangue , Diabetes Mellitus Tipo 2/complicações , Polipeptídeo Inibidor Gástrico/sangue , Neoplasias Pancreáticas/sangue , Polipeptídeo Pancreático/sangue , Redução de Peso , Adulto , Idoso , Biomarcadores/sangue , Carcinoma Ductal Pancreático/complicações , Carcinoma Ductal Pancreático/diagnóstico , Carcinoma Ductal Pancreático/fisiopatologia , Estudos de Casos e Controles , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/fisiopatologia , Feminino , Peptídeo 1 Semelhante ao Glucagon/sangue , Intolerância à Glucose/sangue , Intolerância à Glucose/complicações , Intolerância à Glucose/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Neuropeptídeo Y/sangue , Neoplasias Pancreáticas/complicações , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/fisiopatologia , Peptídeo YY/sangue
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