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1.
Prog Urol ; 32(6S1): 6S43-6S53, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36719646

RESUMO

INTRODUCTION: The aim of this narrative review conducted by the Prostate Cancer Committee of the French Association of Urology (CC-AFU) was to provide an update on the current evidence for the impact of PET/CT in the management of men with non-metastatic castration-resistant prostate cancer (nmCRPC). MATERIAL AND METHODS: This review is based on data available in the literature on PET/CT imaging for staging nmCRPC patients. A PubMed search and narrative review of the data were performed in March 2022. Only articles in French or English were considered. RESULTS: Current guidelines recommend bone scan and CT scan as standard imaging modalities for staging and follow-up of patients with nmCRPC. Nearly one-third of asymptomatic patients with presumed nmCRPC ultimately have metastatic disease on conventional imaging. Increasing reports have shown that conventional imaging has limited accuracy in detecting metastatic disease in nmCRPC patients, leading to the development of next-generation imaging techniques. In a retrospective study, 18F-choline PET/CT detected distant metastases in 27/58 high-risk nmCRPC patients with prior negative conventional imaging. The implementation of radiolabeled ligands of the prostate-specific membrane antigen (PSMA) PET/CT in staging strategy has resulted in metastasis detection in 45% to 98% of patients with presumptive nmCRPC on conventional imaging. Such an early diagnosis of metastatic CRPC may allow patients to be referred for metastasis-directed therapies (i.e. stereotactic body radiotherapy), aimed at prolonging the efficacy of systemic therapies and improving clinical outcomes. However, current data are not strong enough to recommend this strategy, which must be properly evaluated in clinical trials. Indeed, the use of molecular imaging may lead to inappropriate undertreatment if the second-generation androgen receptor inhibitors (darolutamide, enzalutamide, apalutamide), which prolong life, are not used in the subgroup of patients with high PSA velocity (PSA doubling time <10 months). CONCLUSION: Implementation of PSMA-PET/CT in the staging strategy would result in a migration of disease stage to extra-pelvic, M1 disease in at least half of presumed nmCRPC patients. The unprecedented accuracy of PSMA-PET/CT may pave the way for a more personalized treatment strategy. However, no data yet support this strategy for all nmCRPC patients as no oncologic benefit of early detection of M1 disease or MDT has been demonstrated. © 2022 Elsevier Masson SAS. All rights reserved.


Assuntos
Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias de Próstata Resistentes à Castração , Masculino , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Neoplasias de Próstata Resistentes à Castração/terapia , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Antígeno Prostático Específico , Estudos Retrospectivos , Próstata/patologia , Tomografia Computadorizada por Raios X , Castração
2.
Anal Bioanal Chem ; 399(9): 3011-23, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21170522

RESUMO

Enzyme-linked immunosorbent assay (ELISA) analysis of proteins offers a particularly promising approach for investigations in cultural heritage on account of its appreciated properties of being highly specific, sensitive, relatively fast, and cost-affordable with respect to other conventional techniques. In spite of that, it has never been fully exploited for routine analyses of painting materials in consideration of several analytical issues that inhibited its diffusion in conservation science: limited sample dimensions, decrease of binder solubility and reduced availability of antibody bonding sites occurring with protein degradation. In this study, an ELISA analytical protocol suited for the identification of aged denatured proteins in ancient painting micro-samples has been developed. We focused on the detection of bovine ß-casein and chicken ovalbumin as markers of bovine milk (or casein) and chicken albumen, respectively. A systematic experimentation of the ELISA protocol has been carried out on mock-ups of mural and easel painting prepared with 13 different pigments to assess limits and strengths of the method when applied for the identification of proteins in presence of a predominant inorganic matrix. The analytical procedure has been optimized with respect to protein extraction, antibodies' concentrations, incubation time and temperature; it allows the detection of the investigated proteins with sensitivity down to nanograms. The optimized protocol was then tested on artificially aged painting models. Analytical results were very encouraging and demonstrated that ELISA allows for protein analysis also in degraded painting samples. To address the feasibility of the developed ELISA methodology, we positively investigated real painting samples and results have been cross-validated by gas chromatography-mass spectrometry.


Assuntos
Ensaio de Imunoadsorção Enzimática/métodos , Pintura/análise , Pinturas , Proteínas/análise , Animais , Caseínas/análise , Bovinos , Galinhas , Clara de Ovo/análise
3.
Anal Bioanal Chem ; 401(6): 1847-60, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21667062

RESUMO

Chemical analysis of ancient residues of pharmaceutical or cosmetic preparations such as balms or ointments is made problematic by the high complexity of these mixtures, composed of organic and inorganic materials. Consequently, a multi-analytical approach and special caution in the interpretation of the results are necessary. In order to contribute to the improvement of analytical strategies for the characterization of complex residues and to reconstruct ancient medical practices, a replica of a pharmaceutical formulation of the seventeenth century was prepared in the laboratory according to a historically documented recipe. In a round robin exercise, a portion of the preparation was analysed as a blind sample by 11 laboratories using various analytical techniques. These included spectroscopic, chromatographic and mass spectrometric methods. None of the laboratories was able to completely reconstruct the complex formulation, but each of them gave partial positive results. The round robin exercise has demonstrated that the application of a multi-analytical approach can permit a complete and reliable reconstruction of the composition. Finally, on the basis of the results, an analytical protocol for the study of residues of ancient medical and pharmaceutical preparations has been outlined.


Assuntos
Pomadas/química , Tecnologia Farmacêutica/história , Cromatografia Líquida de Alta Pressão , Cromatografia Gasosa-Espectrometria de Massas , História do Século XVII , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman
4.
Oncol Rep ; 21(4): 1083-9, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19288012

RESUMO

Experimental data from in vitro and in vivo models indicate that peroxisome proliferator-activated receptor (PPAR) ligand activation regulates differentiation and induces cell growth arrest and apoptosis in a variety of cancer types. Thiazolidinediones such as ciglitazone (CGZ) constitute the most well-known synthetic ligands for PPARgamma. We previously reported a remarkable antitumor effect of the retinoid 6-OH-11-O-hydroxyphenantrene (IIF), synthetic retinoid X receptors (RXRs) agonist, on many cancer cell lines. Since PPARs bind to DNA as heterodimers with RXRs, in this study we investigated if IIF potentiates the antitumoral properties of the PPARgamma ligand CGZ in glioblastoma U87MG and melanoma G361 cells. Our results show that either IIF or CGZ inhibited cell growth and tissue invasion ability, but these properties were enhanced by using IIF and CGZ in combined treatment. Since matrix metalloproteinases (MMPs) play a major role in tumor cell invasion, we analyzed the effect of IIF and CGZ on MMP2 and MMP9 activity and expression. The addition of IIF to CGZ resulted in a decrease of MMP2 and MMP9 expression and activity, higher than when each agent was used alone. Furthermore, treatment with IIF and/or CGZ enhanced PPARgamma expression but both agents in combined treatment caused the maximum efficiency. Finally, we demonstrated that IIF can potentiate PPARgamma trascriptional activity induced by CGZ, by evaluation of peroxisome proliferator-responsive element transactivation. In conclusion, these findings suggest that the RXR selective retinoid IIF, in combination with the PPARgamma ligand CGZ, may provide a therapeutic advantage in cancer treatment.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias/tratamento farmacológico , PPAR gama/agonistas , Receptores X de Retinoides/agonistas , Tiazolidinedionas/administração & dosagem , Tretinoína/análogos & derivados , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Sinergismo Farmacológico , Humanos , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Invasividade Neoplásica , Neoplasias/patologia , PPAR gama/fisiologia , Receptores X de Retinoides/fisiologia , Tretinoína/administração & dosagem
5.
Anal Bioanal Chem ; 395(7): 2107-18, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19787341

RESUMO

In the present study, the analytical strengths and limitations of near-infrared (NIR) spectroscopy to non-invasively characterize organic components in painting materials have been investigated. In spite of the increased amount of information available today from advanced modern analytical instrumentations dedicated to cultural heritage, the non-invasive identification of materials belonging to the wide class of organic compounds historically used in paintings is still a challenging task. Near-infrared spectroscopy offers several attractive features that make this technique particularly suitable to this purpose. In fact, it is non-invasive, allows for non-contact measurements in reflectance mode, gives molecular information on complex macromolecules, and can be performed on-site by means of portable devices. First-derivative transformation of reflectance spectroscopic data has been applied to provide a simple and fast way to deduce more information from NIR spectra. This approach has allowed spectral features to be identified that can be useful to distinguish different compounds belonging to the classes of lipids, proteins, and resins. To this purpose, at first, a spectral database of pure standard has been collected. Our analytical approach was then successfully validated on pictorial models reproducing the typical stratigraphy of an easel painting. As final step, the study of a real painting has been attempted and a drying oil, animal glue, and a terpenic natural resin, as well as an earth pigment were clearly identified, as cross-validated by GC-MS analysis.

6.
Anticancer Res ; 28(1A): 283-8, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18383858

RESUMO

All-trans retinoic acid (RA) induces complete remission in a high proportion of patients with acute promyelocytic leukemia (APL). Nevertheless, most of these patients develop RA resistance and relapse. In an attemp to mimic clinical conditions for the treatment of leukemia, a stably RA-resistant subclone of the human promyelocytic leukemia cell line HL60 (HL60-R) was developed to study the antiproliferative and proapoptotic effect of the retinoid IIF (6-OH-11-O-hydroxyphenantrene) in comparison with RA. Moreover whether the inhibitor of histone deacetylase (HDAC) activity, valproic acid (VPA), could enhance sensitivity to retinoids in HL60-R cells was evaluated. Finally, the effect of IIF on the expression of multidrug resistance-associated protein 1 (MRP1) and P-glycoprotein (P-gp) was evaluated. It was found that IIF strongly suppressed cell proliferation (as measured by growth curves) and induced apoptosis (as measured by DNA fragmentation and Annexin V detection assays), while RA was practically ineffective. The addition of VPA to IIF accentuated the antiproliferative effect of IIF alone and increased apoptosis; the combination of VPA with RA allowed growth arrest. Moreover IIF caused a reduction of transmembrane transporter expression, particularly of P-gp, as shown by Western blotting. Our results suggest that IIF may be useful in controlling the proliferation of RA-resistant leukemia cells, especially in combination with an HDAC inhibitor, such as VPA.


Assuntos
Leucemia Promielocítica Aguda/tratamento farmacológico , Tretinoína/análogos & derivados , Tretinoína/farmacologia , Ácido Valproico/farmacologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/biossíntese , Apoptose/efeitos dos fármacos , Processos de Crescimento Celular/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos , Células HL-60 , Humanos , Leucemia Promielocítica Aguda/metabolismo , Leucemia Promielocítica Aguda/patologia , Proteínas Associadas à Resistência a Múltiplos Medicamentos/biossíntese
7.
Oncol Rep ; 18(4): 1015-21, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17786368

RESUMO

Glioblastomas, the most malignant and prevalent brain tumors which remain incurable, are characterized by both extensive proliferation and invasive growth. We previously reported a remarkable antitumoral effect of the retinoid 6-OH-11-O-hydroxyphenantrene (IIF) on neuroblastoma, leukemia and colon carcinoma cells. In this study we examined the effect of IIF on proliferation, apoptosis and cell invasion in the human glioblastoma cell line U87MG, in comparison with all-trans-retinoic acid (RA). Our results showed that both retinoids induced cell growth inhibition and apoptosis in a dose- and time-dependent manner. We also demonstrated that the invasive ability of glioblastoma cells decreased after treatment with IIF or RA. Since cell invasion involves a complex system of tightly regulated proteases, matrix metalloproteinases (MMPs) and their specific inhibitors, tissue inhibitors of MMPs (TIMPs), we analysed the effect of IIF on MMP and TIMP expression in comparison with RA. Treatment with both retinoids resulted in a marked decrease of MMP2 and MMP9 expression and of lytic activity of MMP2. In addition, exposure to IIF led to enhanced expression of TIMP2. Collectively, our results demonstrated the effectiveness of both IIF and RA in inhibiting proliferation, cell migration, and the invasive potential of glioblastoma U87MG cells. Notably, the anticancer activity of IIF, on the whole, was more pronounced than that of RA. Therefore, these findings, besides providing further evidence that IIF may be a powerful tool in the development of cancer treatments, suggest that IIF may have therapeutic potential against the invasiveness of brain tumors.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Glioblastoma/tratamento farmacológico , Tretinoína/análogos & derivados , Tretinoína/farmacologia , Anexina A5/metabolismo , Western Blotting , Neoplasias Encefálicas/patologia , Glioblastoma/patologia , Humanos , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Invasividade Neoplásica/patologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Neoplásico/genética , RNA Neoplásico/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Inibidor Tecidual de Metaloproteinase-2/genética , Inibidor Tecidual de Metaloproteinase-2/metabolismo , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/patologia
8.
In Vivo ; 20(6A): 729-33, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17203756

RESUMO

The development of multidrug resistance (MDR) is one of the major causes of failure in cancer therapy. The use of cell lines with acquired resistance to anticancer agents represents a very good tool for investigation into the possibility of reversal of MDR. In this study the ability of all-trans-retinoic acid (RA) and its derivative 6-OH-11-O-hydroxyphenanthrene (IIF; pat. WIPO W000 /117143) as antitumor agents was investigated in the human colon carcinoma cell line LoVo and in the counterpart resistant derivative LoVo/MDR cell line. Cell proliferation was measured by MTT assay, apoptosis was evaluated using DNA fragmentation and Annexin V detection assay. Retinoids suppressed cell proliferation in a time- and dose-dependent manner. Interestingly, IIF was significantly more effective than RA, particularly on LoVo/MDR cells. RA and IIF induced apoptosis in both cell lines, with IIF effect significantly higher than that of RA. Furthermore, on the basis that MDR phenotype is often caused by drug efflux due to overexpression of the membrane P-glycoprotein (P-gp), it was demonstrated that RA and IIF reduced P-gp synthesis in LoVo/MDR cells. Our results suggest that IIF could be a powerful tool in the development of colon carcinoma treatments, even when tumor cells present an MDR phenotype.


Assuntos
Adenocarcinoma/tratamento farmacológico , Antineoplásicos/farmacologia , Neoplasias do Colo/tratamento farmacológico , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Tretinoína/análogos & derivados , Tretinoína/farmacologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Relação Dose-Resposta a Droga , Formazans/metabolismo , Humanos , Sais de Tetrazólio/metabolismo
9.
Cancer Res ; 61(3): 1196-206, 2001 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-11221851

RESUMO

After therapeutic hormone deprivation, prostate cancer (CaP) cells often develop androgen-independent growth through not-well-defined mechanisms. The presence of neuroendocrine (NE) cells is often greater in prostate carcinoma than in normal prostate, and the frequency of NE cells correlates with tumor malignancy, loss of androgen sensitivity, increase of autocrine-paracrine activity, and poor prognosis. In some CaPs, neuropeptides have been previously implicated as growth factors. Peptidylglycine alpha-amidating monooxygenase (PAM) is the enzyme producing alpha-amidated bioactive peptides from their inactive glycine-extended precursors. In the present work, we demonstrate that androgen-independent PC-3 and DU145 cell lines, derived from human CaP, express PAM in vitro and in xenografts implanted in athymic nude mice, indicating that they are able to produce alpha-amidated peptides. Contrarily, barely detectable levels of PAM were found in the androgen-sensitive LNCaP cell line. We also show that whereas PC-3 and DU145 cells produce and secrete adrenomedullin (AM), a multifunctional amidated peptide, no expression was found in LNCaP cells. We further demonstrate that AM acts as a growth factor for DU145 cells, which suggests the existence of an autocrine loop mechanism that could potentially drive neoplastic growth. PAM mRNA levels were found to be 3-fold higher in prostate adenocarcinomas compared with that of human benign prostate hyperplasia (BPH) as demonstrated by real-time quantitative reverse transcription-PCR. The analysis of AM message expression in BPH and CaP (Gleason's score, 6-9) shows a clear distinction between benign and CaP. The expression was detected only in adenocarcinomas tissues with a marked increase in samples with a high Gleason's score. Immunocytochemically, AM was localized in the carcinomatous epithelial compartment. NE phenotype, assessed after the immunocytochemical localization of neuron-specific enolase (NSE), was found in both the epithelial and the stromal compartments of cancers; in BPH, only some spare basal cells were NSE-labeled. Cancer progression could be accelerated by peptides secreted by a population of cells capable of inducing androgen-independent tumoral growth via autocrine-paracrine mechanisms.


Assuntos
Adenocarcinoma/metabolismo , Oxigenases de Função Mista/metabolismo , Complexos Multienzimáticos , Peptídeos/metabolismo , Neoplasias da Próstata/metabolismo , Adenocarcinoma/enzimologia , Adrenomedulina , Animais , Divisão Celular/efeitos dos fármacos , Humanos , Imuno-Histoquímica , Hibridização In Situ , Masculino , Camundongos , Camundongos Nus , Oxigenases de Função Mista/biossíntese , Oxigenases de Função Mista/genética , Proteínas de Neoplasias/metabolismo , Transplante de Neoplasias , Neoplasias Hormônio-Dependentes/enzimologia , Neoplasias Hormônio-Dependentes/metabolismo , Peptídeos/genética , Peptídeos/farmacologia , Fosfopiruvato Hidratase/metabolismo , Hiperplasia Prostática/enzimologia , Hiperplasia Prostática/metabolismo , Neoplasias da Próstata/enzimologia , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transplante Heterólogo , Células Tumorais Cultivadas
10.
J Steroid Biochem Mol Biol ; 96(5): 355-65, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16043352

RESUMO

After castration or therapeutic hormone deprivation, most cancer of the prostate (CaP) cells develop androgen-independent (AI) growth. In this work, we studied the effect of androgen depletion (castration) on the growth of experimental model LuCaP 23.1 xenograft. A total of 101 nude mice were implanted and analysed for their growth profile before experimental period 1 (11 weeks) and after castration experimental period 2 (15 weeks). For specific periods, tumors were harvested and assessed for molecular marker expression specific for CaP. Taking into account tumor dynamic growth, prior to castration we found 37 fast growing (FG) tumors (948.9+/-76.9 mm3) and 63 slow growing (SG) tumors (229.6+/-18.4 mm3). Real-time quantitative RT-PCR showed that in comparison to SGs, FGs contained elevated expression of epidermal growth factor receptor type 1 (HER1), urokinase plasminogen activator (uPA), thymidine phosphorylase (TP) and thymidilate synthase (TS) mRNAs expression and low levels of 5alpha-reductase 2 (5alpha-R2) mRNA. After castration all FG tumors progressed rapidly (by 5 weeks) to AI growth (FG-P). In SG castrated tumors, 66% of tumors showed retarded progression (by 12 weeks) to AI (SG-P), whereas 34% responded to castration (SG-R). Molecular analysis demonstrated distinct molecular profiles integrating different pathways associated with AI progression. The progressive tumors FG-P, and some tumors of SG-P subgroup, presented significantly high levels of HER1, epidermal growth factor receptor type 2 (HER2), TS, uPA, TP, tumor necrosis factor superfamily member 6 (FAS) and peptidylglycine alpha-amidating mono-oxygenase (PAM) mRNA all of which correlated with androgen receptor (AR) mRNA. The second subgroup of SG-P tumors showed a high expression of the anti-apoptotic gene Bcl-2. A third subgroup of SG-P tumors showed significant expression of hypoxia-related genes such as adrenomedullin (AM) after castration. LuCaP 23.1 xenograft represent a useful dynamic model to study pre-clinically new therapeutic molecules and evaluate non-randomized therapeutics protocols combining different target inhibition specific to each AI pathways.


Assuntos
Androgênios/fisiologia , Peptídeos Catiônicos Antimicrobianos/metabolismo , Neoplasias da Próstata/metabolismo , Transplante Heterólogo , Adrenomedulina , Animais , Castração , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Peptídeos/metabolismo , Antígeno Prostático Específico/metabolismo , Timidina Fosforilase/metabolismo , Fatores de Necrose Tumoral/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
11.
Radiat Prot Dosimetry ; 115(1-4): 122-5, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16381696

RESUMO

The management of radioactive waste is a key issue for the present and future use of nuclear energy. In this frame, high temperature reactors (HTRs) have, among others, the capability to burn actinides. After a short introduction on HTRs, the performances of two MC-based burnup codes (Monte Carlo continuous energy burnup and MONTEBURNS) in assessing the ability of these reactors to burn actinides are compared. These codes are necessary for performing ultra-high burnup calculations on HTRs. The best one, in this specific case, results to be MONTEBURNS. It was analysed using HTRs loaded with the following: (1) 1st generation Pu, 600 equivalent full power days; (2) 2nd generation Pu, 645 equivalent full power days; and (iii) 33% 1st generation Pu and 67% Th, 705 equivalent full power days. Finally, it is possible to conclude that HTRs can reduce time when the waste is considered dangerous. Even if the amount of reduction does not solve the whole problem, it represents an important step in the management of radioactive waste.


Assuntos
Resíduos Industriais/prevenção & controle , Reatores Nucleares , Monitoramento de Radiação/métodos , Proteção Radiológica/instrumentação , Radioisótopos/análise , Radioisótopos/química , Eliminação de Resíduos/instrumentação , Simulação por Computador , Análise de Falha de Equipamento/métodos , Meia-Vida , Temperatura Alta , Modelos Químicos , Modelos Estatísticos , Doses de Radiação , Proteção Radiológica/métodos , Radioisótopos/toxicidade , Medição de Risco/métodos , Fatores de Risco
12.
Exp Hematol ; 25(12): 1253-60, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9357969

RESUMO

Stem cell factor (SCF) is a glycoprotein growth factor produced by marrow stromal cells that acts after binding to its specific surface receptor, which is the protein encoded by the protooncogene c-kit. SCF synergizes with specific lineage factors in promoting the proliferation of primitive hematopoietic progenitors, and has been administered to expand the pool of these progenitors in cancer patients treated with high-dose chemotherapy. SCF and its c-kit receptor are expressed by some tumor cells, including myeloid leukemia, breast carcinoma, small cell lung carcinoma, melanoma, gynecological tumors, and testicular germ cell tumors. Previous studies of SCF in neuroblastoma have produced conflicting conclusions. To explore the role of SCF in neuroblastoma, we studied five neuroblastoma lines (IMR-5, SK-N-SH, SK-N-BE, AF8, and SJ-N-KP) and the neuroepithelioma line CHP-100. All lines expressed mRNA for c-kit and c-kit protein at low intensity as measured by flow cytometry, and secreted SCF in medium culture as shown by ELISA. Exogenous SCF did not modify 3H thymidine uptake in the neuroblastoma and neuroepithelioma cell lines. After 6 days' culture in the presence of anti-c-kit, the number of viable neuroblastoma cells was significantly lower than the control, and terminal deoxynucleotidyl transferase assay showed a substantial increase of apoptotic cells: The percentage of positive cells was 1-3% in the control lines, whereas in the presence of anti c-kit it varied from 29% of SK-N-BE to 92% of CHP-100. After 9 days' culture in the presence of anti-c-kit, no viable cells were detectable. These data indicate that SCF is produced by some neuroblastoma cell lines via an autocrine loop to protect them from apoptosis.


Assuntos
Apoptose/efeitos dos fármacos , Mitógenos/farmacologia , Neuroblastoma/patologia , Tumores Neuroectodérmicos Primitivos Periféricos/patologia , Proteínas Proto-Oncogênicas c-kit/fisiologia , Fator de Células-Tronco/farmacologia , Anticorpos Monoclonais , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Proteínas Proto-Oncogênicas c-kit/genética , RNA Mensageiro/genética , RNA Neoplásico/genética , Fator de Células-Tronco/biossíntese , Células Tumorais Cultivadas
13.
J Small Anim Pract ; 56(11): 679-83, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25958888

RESUMO

This report describes a case of severe spontaneous tension pneumopericardium with concurrent pneumomediastinum, pneumothorax and retropneumoperitoneum in a cat presenting with dyspnoea and signs of cardiac tamponade secondary to metastatic pulmonary carcinoma. Spontaneous pneumopericardium is an extremely uncommon condition consisting of pericardial gas in the absence of iatrogenic/traumatic causes. In humans, it has been described secondary to pneumonia or lung abscess and very rarely secondary to pulmonary neoplasia.


Assuntos
Doenças do Gato/patologia , Neoplasias Pulmonares/veterinária , Enfisema Mediastínico/veterinária , Pneumopericárdio/veterinária , Pneumotórax/veterinária , Retropneumoperitônio/veterinária , Animais , Gatos , Feminino , Neoplasias Pulmonares/complicações , Neoplasias Pulmonares/patologia , Enfisema Mediastínico/etiologia , Enfisema Mediastínico/patologia , Pneumopericárdio/etiologia , Pneumopericárdio/patologia , Pneumotórax/etiologia , Pneumotórax/patologia , Retropneumoperitônio/etiologia , Retropneumoperitônio/patologia , Tomografia Computadorizada por Raios X/veterinária
14.
J Cancer Res Clin Oncol ; 105(1): 111-2, 1983.
Artigo em Inglês | MEDLINE | ID: mdl-6339513

RESUMO

The mutagenic power of 1,2-dichloroethane, 1,2-dibromoethane, 1,2-diiodoethane was tested in the human cell line, EUE. In our mutagenic system, based on selection against diphtheria toxin, the halogenated compounds, 1,2-dichloroethane and 1,2-dibromoethane revealed a strong mutagenic effect, whereas 1,2-diiodoethane was not mutagenic at a concentration allowing survival of 41%.


Assuntos
Dibrometo de Etileno/farmacologia , Dicloretos de Etileno/farmacologia , Hidrocarbonetos Bromados/farmacologia , Hidrocarbonetos Clorados/farmacologia , Mutação/efeitos dos fármacos , Linhagem Celular , Toxina Diftérica , Relação Dose-Resposta a Droga , Humanos , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genética
15.
Cortex ; 29(4): 675-89, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8124943

RESUMO

The study of visuo-spatial imagery abilities in totally congenitally blind people may be instrumental in understanding the contribution of visual experience to imagery processes. In the present paper visuo-spatial imagery capacity was explored through a task devised by Kerr (1987) and adapted for presentation to the blind, in which subjects were asked to imagine either two- or three-dimensional matrices of different complexity and to follow a mental pathway. The first experiment showed that blind people have difficulty with three-dimensional matrices which are within the reach of sighted people, and that their performance is affected by the processing rate. In the second experiment the spatial and pictorial components of visual imagery were analyzed by way of the same spatial task and of a pictorial-tactual task in which subjects had to match a mental representation of a pathway to a tactually explored wire silhouette. On the latter task, blind people did not meet any particular difficulty, probably because they could form representations using other sensory modalities and because they were skillful in tactual exploration. These data suggest that research on the blind cannot easily contribute to the distinction between the spatial and pictorial components of visual imagery.


Assuntos
Cegueira/congênito , Imaginação , Reconhecimento Visual de Modelos , Percepção Espacial , Estereognose , Adolescente , Adulto , Cegueira/psicologia , Percepção de Profundidade , Feminino , Humanos , Masculino , Rememoração Mental , Pessoa de Meia-Idade , Orientação
16.
Anticancer Res ; 7(2): 247-50, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3473974

RESUMO

On the basis that inhibition of cell proliferation may play a role in the differentiation process, we have studied the effect of the antineoplastic drug epirubicin, an antibiotic of the anthracycline group, on human neuroblastoma cell lines SK-N-MC, SK-N-SH, SJ-N-KP, TS12 and AF8. Epirubicin induced morphological and biochemical differentiation in these cultured cell lines; treatment with it stimulated the outgrowth of neurites and increased acetylcholinesterase activity.


Assuntos
Doxorrubicina/farmacologia , Neuroblastoma/patologia , Acetilcolinesterase/metabolismo , Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Epirubicina , Inibidores do Crescimento/farmacologia , Humanos , Técnicas In Vitro , Fatores de Tempo
17.
Anticancer Res ; 18(2A): 1099-103, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9615772

RESUMO

Butyric acid has been shown in vitro to produce cytodifferentiation of a wide variety of neoplastic cells. The potential clinical use of this compound as a therapeutic agent is limited by its rapid metabolism. This has led to the examination, as potential antineoplastic agents, of compounds structurally correlated to butyrate, with longer biological half lives. In this study we investigated the effect in vitro of two butyrate analogues, tributyrin and butyramide, on inducing growth inhibition and expression of morphological and immunophenotypic properties, in human neuroblastoma cell lines. Treatment with tributyrin resulted in a strong inhibition of cell proliferation and in induction of extensive differentiation; on the contrary butyramide was scarcely effective or quite ineffective. These results demonstrate that tributyrin retains the effectiveness of butyrate and suggest that this analogue could have utility for cytodifferentiation therapy.


Assuntos
Amidas/farmacologia , Neuroblastoma/patologia , Compostos de Trialquitina/farmacologia , Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Humanos , Fenótipo , Células Tumorais Cultivadas
18.
Anticancer Res ; 8(6): 1303-6, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3218962

RESUMO

The effect of different Esorubicin concentrations (10(-7) M to 10(-10) M) has been tested on the in vitro growth of human normal hemopoietic progenitor cells and of three leukemic cell lines (K562, U 937, HL60). The highest drug concentration completely abolished both normal and leukemic proliferation. Lower doses of Esorubicin failed to induce any morphological or phenotypic differentiation of leukemic cell lines. A 24h pretreatment of the cells with 10(-9) M Esorubicin enhanced the in vitro proliferation of normal early myeloid progenitor cells, whereas it did not affect leukemic, myelomonocytic cell proliferation.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Doxorrubicina/análogos & derivados , Células-Tronco Hematopoéticas/citologia , Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Células Cultivadas , Doxorrubicina/farmacologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Humanos , Leucemia , Valores de Referência
19.
Anticancer Res ; 7(6): 1197-200, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3481683

RESUMO

Epirubicin, at concentrations ranging between 10(-7) and 10(-13) M, was assayed in semisolid cultures of human normal hemopoietic cells and in liquid cultures of 5 different human leukemic cell lines. The growth of all normal hemopoietic progenitor cells was inhibited by the higher drug concentrations; at the lowest concentration, only CFU-E and 7th-day CFU-GM were not inhibited. On the other hand, leukemic cells were sensible only to the higher concentration of epirubicin, which, nevertheless, was not fully inhibitory. Leukemic cell differentiation was not promoted by the drug, as evidenced by a panel of monoclonal antibodies, by cytochemistry and by functional tests. These results suggest a marked in vitro myelotoxicity of epirubicin, that does not appear to be compensated by a powerful control of leukemic cell proliferation.


Assuntos
Doxorrubicina/farmacologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Leucemia/sangue , Anticorpos Monoclonais , Medula Óssea/efeitos dos fármacos , Ensaio de Unidades Formadoras de Colônias , Epirubicina , Histocitoquímica , Humanos , Técnicas In Vitro , Fagocitose , Timidina/metabolismo , Células Tumorais Cultivadas/efeitos dos fármacos
20.
Anticancer Res ; 9(6): 1605-9, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2627114

RESUMO

The effects of epirubicin and retinoic acid (RA) as differentiation inducing agents on human neuroblastoma cell lines were investigated. We have compared the response of neuroblastoma cells to epirubicin alone, to RA alone and to combined treatment, with respect to neuritic processes outgrowth, acethylcholinesterase activity, growth inhibition and antigenic expression. The obtained data indicate that the combination of the two agents is able to produce a synergistic effect on differentiation and on growth inhibition.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Epirubicina/farmacologia , Neuroblastoma/patologia , Tretinoína/farmacologia , Células Tumorais Cultivadas/efeitos dos fármacos , Acetilcolinesterase/metabolismo , Linhagem Celular , Interações Medicamentosas , Humanos , Imuno-Histoquímica , Células Tumorais Cultivadas/citologia , Células Tumorais Cultivadas/enzimologia
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