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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.
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
3.
Cell Death Dis ; 5: e1016, 2014 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-24457960

RESUMO

The proapoptotic protein, prostate apoptosis response-4 (Par-4), acts as a tumor suppressor in prostate cancer cells. The serine/threonine kinase casein kinase 2 (CK2) has a well-reported role in prostate cancer resistance to apoptotic agents or anticancer drugs. However, the mechanistic understanding on how CK2 supports survival is far from complete. In this work, we demonstrate both in rat and humans that (i) Par-4 is a new substrate of the survival kinase CK2 and (ii) phosphorylation by CK2 impairs Par-4 proapoptotic functions. We also unravel different levels of CK2-dependent regulation of Par-4 between species. In rats, the phosphorylation by CK2 at the major site, S124, prevents caspase-mediated Par-4 cleavage (D123) and consequently impairs the proapoptotic function of Par-4. In humans, CK2 strongly impairs the apoptotic properties of Par-4, independently of the caspase-mediated cleavage of Par-4 (D131), by triggering the phosphorylation at residue S231. Furthermore, we show that human Par-4 residue S231 is highly phosphorylated in prostate cancer cells as compared with their normal counterparts. Finally, the sensitivity of prostate cancer cells to apoptosis by CK2 knockdown is significantly reversed by parallel knockdown of Par-4. Thus, Par-4 seems a critical target of CK2 that could be exploited for the development of new anticancer drugs.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Apoptose , Caseína Quinase II/metabolismo , Neoplasias da Próstata/metabolismo , Motivos de Aminoácidos , Animais , Proteínas Reguladoras de Apoptose/química , Proteínas Reguladoras de Apoptose/genética , Caseína Quinase II/genética , Linhagem Celular Tumoral , Humanos , Masculino , Fosforilação , Neoplasias da Próstata/enzimologia , Neoplasias da Próstata/genética , Neoplasias da Próstata/fisiopatologia , Ratos
4.
Cell Death Dis ; 2: e221, 2011 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-22012255

RESUMO

Despite many advances in oncology, almost all patients with pancreatic cancer (PC) die of the disease. Molecularly targeted agents are offering hope for their potential role in helping translate the improved activity of combination chemotherapy into improved survival. Heat shock protein 27 (Hsp27) is a chaperone implicated in several pathological processes such as cancer. Further, Hsp27 expression becomes highly upregulated in cancer cells after chemotherapy. Recently, a modified antisense oligonucleotide that is complementary to Hsp27 (OGX-427) has been developed, which inhibits Hsp27 expression and enhances drug efficacy in cancer xenograft models. Phase II clinical trials using OGX-427 in different cancers like breast, ovarian, bladder, prostate and lung are in progress in the United States and Canada. In this study, we demonstrate using TMA of 181 patients that Hsp27 expression and phosphorylation levels increase in moderately differentiated tumors to become uniformly highly expressed in metastatic samples. Using MiaPaCa-2 cells grown both in vitro and xenografted in mice, we demonstrate that OGX-427 inhibits proliferation, induces apoptosis and also enhances gemcitabine chemosensitivity via a mechanism involving the eukaryotic translation initiation factor 4E. Collectively, these findings suggest that the combination of Hsp27 knockdown with OGX-427 and chemotherapeutic agents such as gemcitabine can be a novel strategy to inhibit the progression of pancreas cancer.


Assuntos
Desoxicitidina/análogos & derivados , Proteínas de Choque Térmico HSP27/genética , Oligonucleotídeos Antissenso/genética , Oligonucleotídeos Antissenso/farmacologia , Neoplasias Pancreáticas/terapia , Animais , Linhagem Celular Tumoral , Desoxicitidina/farmacologia , Progressão da Doença , Sinergismo Farmacológico , Proteínas de Choque Térmico HSP27/metabolismo , Proteínas de Choque Térmico , Humanos , Masculino , Camundongos , Camundongos Nus , Chaperonas Moleculares , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Fosforilação , Prognóstico , Ensaios Antitumorais Modelo de Xenoenxerto , Gencitabina
5.
Curr Cancer Drug Targets ; 11(8): 954-65, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21861840

RESUMO

Castration-resistant prostate cancer remains incurable and a major cause of mortality worldwide. The absence of effective therapeutic approaches for advanced prostate cancer has led to an intensive search for novel treatments. Emerging nanomedical approaches have shown promising results, in vitro and in vivo, in improving drug distribution and bioavailability, tumor penetration and in limiting toxicity. Nanoscaled carriers bearing finely controlled size and surface properties such as liposomes, dendrimers and nanoparticles have been developed for successful passive and active tumortargeting. Enhanced pharmacokinetics of nanotherapeutics, through improved target delivery and prolonged tissue halflife provides optimal drug delivery that is tumor-specific. Tumor-targeting may be improved through ligand directed delivery systems binding to tumor-specific surface receptors improving cellular uptake through receptor-mediated endocytosis. Recently published data have provided pre-clinical evidence showing the potential of active-targeted nanotherapeutics in prostate cancer therapy; unfortunately, only a few of these therapies have translated into early phase clinical trials development. Hence, progress of active-targeted nanotherapy improving efficiency of site-specific drug delivery is a critical challenge in future clinical treatment of prostate cancer. Exploring specific prostate cell-surface antigens or receptor overexpression may elaborate promising strategies for future therapeutic design. This review presents an overview of some new strategies for prostate cancer active-targeting nanotherapeutics.


Assuntos
Antineoplásicos/administração & dosagem , Portadores de Fármacos/administração & dosagem , Terapia de Alvo Molecular , Nanoestruturas , Neoplasias da Próstata/tratamento farmacológico , Animais , Antineoplásicos/uso terapêutico , Portadores de Fármacos/uso terapêutico , Humanos , Masculino , Nanomedicina/métodos , Nanomedicina/tendências , Nanoestruturas/química
6.
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
7.
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
8.
Oncogene ; 29(13): 1883-96, 2010 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-20101233

RESUMO

One strategy to improve therapies in advanced prostate cancer (PC) involves targeting genes that are activated by androgen withdrawal to delay the emergence of the androgen-independent (AI) phenotype. Heat shock protein 27 (Hsp27) expression becomes highly upregulated in PC cells after androgen withdrawal or chemotherapy, in which it functions as a cytoprotective chaperone to confer broad-spectrum treatment resistance. The purpose of this study is to elucidate anti-apoptotic pathways regulated by Hsp27 that are activated during PC progression. Using two-hybrid experiment, we found that Hsp27 was having a major role in the protein translational initiation process. Furthermore, using complementary DNA (cDNA) microarray analysis, 4E binding protein 1 was identified as being proportionately and highly regulated by Hsp27. These data led us to analyze the protein synthesis initiation pathway, which is a prerequisite for cell growth and proliferation. Using northern and western blot analysis, we found that Hsp27 downregulation decreased eukaryotic translation initiation factor 4E (eIF4E) expression at the protein, but not mRNA, level. The cytoprotection afforded by Hsp27 overexpression was attenuated by eIF4E knockdown using specific eIF4E short interfering RNA (siRNA). Co-immunoprecipitation and co-immunofluorescence confirmed that Hsp27 colocalizes and interacts directly with eIF4E. Hsp27-eIF4E interaction decreases eIF4E ubiquitination and proteasomal degradation. By chaperoning eIF4E, Hsp27 seems to protect the protein synthesis initiation process to enhance cell survival during cell stress induced by castration or chemotherapy. Forced overexpression of eIF4E induces resistance to androgen-withdrawal and paclitaxel treatment in the prostate LNCaP cells in vitro. These findings identify Hsp27 as a modulator of eIF4E and establish a potential mechanism for the eIF4E-regulated apoptosis after androgen ablation and chemotherapy. Targeting Hsp27-eIF4E interaction may serve as a therapeutic target in advanced PC.


Assuntos
Androgênios/administração & dosagem , Proteínas de Choque Térmico HSP27/metabolismo , Neoplasias da Próstata/metabolismo , Antagonistas de Androgênios/farmacologia , Androgênios/farmacologia , Antineoplásicos Hormonais/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Progressão da Doença , Fator de Iniciação 4E em Eucariotos , Células HeLa , Proteínas de Choque Térmico , Humanos , Masculino , Chaperonas Moleculares/farmacologia , Neoplasias da Próstata/enzimologia , RNA Interferente Pequeno/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
9.
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.

10.
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
11.
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
12.
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
13.
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
14.
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
15.
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
16.
Anticancer Res ; 24(3a): 1779-83, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15274355

RESUMO

Vitamin A and its metabolic forms, like all-trans retinoic acid (ATRA), are used with promising results in the treatment of many tumors. Two major problems in the clinical use of retinoids are that the doses needed for successful treatment are often toxic, leading to "hypervitaminosis A syndrome" and that patients often develop drug resistance. In order to find compounds that can overcome these problems, many new derivatives of retinoids have been synthesized and tested. Here we present a study on the effect of a new derivative of retinoic acid, IIF (pat. WIPO W0 00/17143), on growth and differentiation of two colon carcinomna cell lines, CaCo-2 and HT-29, with different degrees of tumorigenicity, the second one being more undifferentiated. The effect of IIF was compared with that of ATRA, whose antitumoral action on colon cancer cells and other tumoral cells is widely described in the literature. Besides exerting a strong antiproliferative effect, even higher than that of ATRA, IIF induced cellular differentiation, as demonstrated by the appearance of morphological (domes and microvilli formation) and biochemical (alkaline phosphatase induction) markers. Therefore, these findings indicate the new retinoid IIF as a possible candidate in the treatment of colon cancer.


Assuntos
Antineoplásicos/farmacologia , Neoplasias do Colo/tratamento farmacológico , Tretinoína/análogos & derivados , Tretinoína/farmacologia , Células CACO-2 , Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Neoplasias do Colo/patologia , Células HT29 , Humanos
18.
Anticancer Res ; 23(2B): 1495-9, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12820415

RESUMO

Neuroblastoma, a tumor originating from the sympathetic nervous system, is the most common extracranial malignant solid tumor of childhood. Human neuroblastoma cells may differentiate in vitro under treatment with a variety of biological agents and drugs. Among these, retinoic acid (RA) is quite potent and its effectiveness as a therapeutic agent is now being evaluated in clinical trials. As its pleiotropic biological activities may produce side-effects limiting clinical use, it is important to find new compounds that present the same effectiveness together with few side-effects. In this study we have explored the action of IIF, (pat. WIPO W0 00/17143) a new derivative of RA, as a differentiation inducer in the human neuroblastoma cell line TS12. In the same cell line, we have also compared the effect of IIF with that of all trans RA (ATRA) and of 9 cis RA (9cRA), with respect to morphological and biochemical differentiation and growth inhibition. Treatment with IIF resulted in a strong inhibition of proliferation and in a marked induction of neuronal differentiation as revealed by neurite extension, increase of actylcholinesterase (AchE) specific activity and tyrosine hydroxylase (TH) expression. The results demonstrate the effectiveness of this new retinoid as a differentiation inducer on neuroblastoma cells TS12. Furthermore, the differentiation-promoter and antimitotic activities of IIF were on the whole more pronounced than those of ATRA and 9cRA. Therefore our study suggests the evaluation of the new retinoid IIF as a therapeutic approach in the treatment of neuroblastoma.


Assuntos
Antineoplásicos/farmacologia , Neuroblastoma/patologia , Tretinoína/farmacologia , Alitretinoína , Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Neuritos/efeitos dos fármacos , Fenótipo , Tretinoína/análogos & derivados , Células Tumorais Cultivadas/citologia , Células Tumorais Cultivadas/efeitos dos fármacos
19.
Minerva Med ; 93(4): 315-20, 2002 Aug.
Artigo em Italiano | MEDLINE | ID: mdl-12207202

RESUMO

BACKGROUND: To assess the long term safety and therapeutic action of lornoxicam, a new non steroidal anti-inflammatory agent, in rheumatoid arthritis. METHODS: Open trial was carried out on different dosage schedules of lornoxicam (4 or 8 mg bid and 4mg tid) administered for six to twelve months. Patients of both sexes were enrolled, with classical or definite rheumatoid arthritis according to the A.R.A. criteria. RESULTS: Thirty-four patients (28 F, 6 M) were admitted, mean age (+/- SD) 53.9+/-14.2 years, mean duration of illness 9.2+/-10.7 years. Lornoxicam 8-16 mg/day showed good safety and therapeutic activity in long term treatment. Clinical improvement was limited, but progression of the disease was controlled. No adverse events were complained. CONCLUSIONS: Lornoxicam presented a worth-while therapeutic action and a good tolerability in rheumatoid arthritis long term treatment.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Piroxicam/análogos & derivados , Piroxicam/uso terapêutico , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
20.
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
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