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1.
J Stomatol Oral Maxillofac Surg ; 122(1): 83-87, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32622001

RESUMO

PURPOSE: The purpose of this study was to reveal the frequency between cleft lip/palate and leukemia in pediatric patients by a systematic analysis of the current literature. MATERIALS AND METHODS: Electronic search on three database (PubMed, Web of Science, Cochrane) was carried out using the following keywords: cleft lip, cleft palate, facial cleft, oral cleft, orofacial cleft, leukemia, acute myeloid leukemia, acute lymphocytic leukemia, lymphoma. Studies published until March 2020 reporting an association between leukemia and cleft lip/palate (CL/P) were included in our research. RESULTS: Five articles (2 case-controls, 3 cohorts), met the inclusion criteria. Case-control studies involved 268 patients with acute lymphocytic leukemia (ALL) and 177 patients with acute myeloid leukemia (AML), of which 9 patients had CL/P. The cohorts studies involved 10 patients with ALL, of which 6 patients with CL/P, 2 patients with cleft palate and 1 patient with cleft lip and palate. CONCLUSION: This research was able to indicate a limited evidence of the association between CL/P and leukemia. In order to draw a clear conclusion, studies with larger cohorts are needed to establish this correlation.


Assuntos
Fenda Labial , Fissura Palatina , Leucemia , Criança , Fenda Labial/diagnóstico , Fenda Labial/epidemiologia , Fissura Palatina/diagnóstico , Fissura Palatina/epidemiologia , Humanos , Leucemia/diagnóstico , Leucemia/epidemiologia
2.
Zoonoses Public Health ; 64(6): 485-490, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28328183

RESUMO

Patients receiving immunosuppressive cancer treatments in settings where there is a high degree of human-animal interaction may be at increased risk for opportunistic zoonotic infections or reactivation of latent infections. We sought to determine the seroprevalence of selected zoonotic pathogens among patients diagnosed with haematologic malignancies and undergoing chemotherapeutic treatments in Romania, where much of the general population lives and/or works in contact with livestock. A convenience sample of 51 patients with haematologic cancer undergoing chemotherapy at a referral clinic in Cluj-Napoca, Romania, was surveyed regarding animal exposures. Blood samples were obtained and tested for evidence of infection with Bartonella species, Coxiella burnetii and Toxoplasma gondii, which are important opportunistic zoonotic agents in immunocompromised individuals. 58.8% of participants reported living or working on a farm, and living or working on a farm was associated with contact with livestock and other animals. 37.5% of participants were IgG seroreactive against one or more of five Bartonella antigens, and seroreactivity was statistically associated with living on farms. Farm dwellers were 3.6 times more likely to test IgG seroreactive to Bartonella antibodies than non-farm dwellers. 47.1% of the participants tested T. gondii IgG positive and 13.7% tested C. burnetii IgG positive, indicating past or latent infection. C. burnetii IgM antibodies were detected in four participants (7.8%), indicating possible recent infection. These results indicate that a large proportion of patients with haematologic cancer in Romania may be at risk for zoonotic infections or for reactivation of latent zoonotic infections, particularly with respect to Bartonella species. Special attention should be paid to cancer patients' exposure to livestock and companion animals in areas where much of the population lives in rural settings.


Assuntos
Infecções por Bartonella/complicações , Leucemia/complicações , Febre Q/complicações , Estudos Soroepidemiológicos , Toxoplasmose/complicações , Adulto , Animais , Bartonella/isolamento & purificação , Infecções por Bartonella/epidemiologia , Coxiella/isolamento & purificação , Feminino , Humanos , Leucemia/epidemiologia , Masculino , Pessoa de Meia-Idade , Febre Q/epidemiologia , Fatores de Risco , Romênia/epidemiologia , Toxoplasma/isolamento & purificação , Toxoplasmose/epidemiologia , Zoonoses
3.
Rom J Intern Med ; 54(3): 194-200, 2016 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-27658169

RESUMO

Hematopoietic stem cell transplantation is an established treatment for many malignant and non-malignant haematological disorders. In the current case report, we describe the first haploidentical stem cell transplantation, used for the first time in Romania, the case of a 33 year-old young woman diagnosed with Hodgkin's lymphoma that has underwent a haploSCT after she relapsed from several chemotherapy regimens, as well as after an autologous stem cell transplantation. This success represents a prèmiere in Romanian clinical hematology, being the first case of a haploSCT in Romania, as well as in South-Eastern Europe.


Assuntos
Transplante de Células-Tronco Hematopoéticas/métodos , Doença de Hodgkin/terapia , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Feminino , Haplótipos , Doença de Hodgkin/tratamento farmacológico , Humanos , Recidiva , Romênia , Condicionamento Pré-Transplante , Transplante Homólogo
4.
Rom J Intern Med ; 54(2): 98-104, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27352438

RESUMO

From an oncological perspective, the second most common malignancies in children are brain tumors. Despite the recent therapeutic breakthroughs in this field, concerning surgery, radiotherapy and chemotherapy alike, some cases still have poor outcomes in curability. This is especially the case in patients with high-risk histological types of tumors, and those suffering from residual, remitting and disseminated diseases. Due to the unique neuroanatomical emplacement of brain tumors and their aggressive infiltrative behavior, their total removal remains a demanding task. This can be perceived in the high rates of failure treatment and disease recurrence. Furthermore, the adjacent healthy brain tissue is inevitably damaged in the surgical process of effectively removing these tumors. Thus, stem cell transplantation may be a viable solution for the clinical management of these malignancies, as proven by various recent breakthroughs. In the current concise review, we present the role of next generation sequencing in HLA typing for stem cell transplantation in primary CNS pediatric malignancies.


Assuntos
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/cirurgia , Genótipo , Teste de Histocompatibilidade , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/cirurgia , Transplante de Células-Tronco , Alelos , Neoplasias Encefálicas/patologia , Criança , Medicina Baseada em Evidências , Teste de Histocompatibilidade/métodos , Humanos , Invasividade Neoplásica , Recidiva Local de Neoplasia/patologia , Transplante de Células-Tronco/métodos , Resultado do Tratamento
5.
Cell Death Differ ; 22(1): 34-45, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25236394

RESUMO

Exosomes are cell-derived vesicles that convey key elements with the potential to modulate intercellular communication. They are known to be secreted from all types of cells, and are crucial messengers that can regulate cellular processes by 'trafficking' molecules from cells of one tissue to another. The exosomal content has been shown to be broad, composed of different types of cytokines, growth factors, proteins, or nucleic acids. Besides messenger RNA (mRNA) they can also contain noncoding transcripts such as microRNAs (miRNAs), which are small endogenous cellular regulators of protein expression. In diseases such as cancer, exosomes can facilitate tumor progression by altering their vesicular content and supplying the tumor niche with molecules that favor the progression of oncogenic processes such as proliferation, invasion and metastasis, or even drug resistance. The packaging of their molecular content is known to be tissue specific, a fact that makes them interesting tools in clinical diagnostics and ideal candidates for biomarkers. In the current report, we describe the main properties of exosomes and explain their involvement in processes such as cell differentiation and cell death. Furthermore, we emphasize the need of developing patient-targeted treatments by applying the conceptualization of exosomal-derived miRNA-based therapeutics.


Assuntos
Exossomos , Regulação Neoplásica da Expressão Gênica , MicroRNAs , Neoplasias , Biossíntese de Proteínas , RNA Neoplásico , Animais , Morte Celular , Diferenciação Celular/genética , Proliferação de Células/genética , Exossomos/genética , Exossomos/metabolismo , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Invasividade Neoplásica , Metástase Neoplásica , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , RNA Neoplásico/genética , RNA Neoplásico/metabolismo
6.
Med Hypotheses ; 83(5): 530-2, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25267320

RESUMO

Most of the body iron is found within hemoglobin in red cells (the erythron), a smaller amount being distributed in other tissues such as muscles and in deposits. Iron homeostasis is a finely tuned process in which the most important regulators are probably the liver-derived hepcidin which blocks iron absorption and directs iron towards deposits and the recently discovered erythroblast-derived erythroferrone which inhibits hepcidin synthesis and therefore increases availability of iron for hemoglobin synthesis. Hepcidin secretion is increased by inflammatory cytokines and erythroferrone production increases when there is active, expanding erythropoiesis, for example after acute blood loss. We hypothesize that in pathological situations associated with erythroid precursor suppression (erythroblastopenia), anemia is the result of two major mechanisms: (1) direct erythroblast suppression leading to decreased production of red cells and (2) low iron availability due to high hepcidin levels arising as a result of low erythroferrone production. Additionally, infectious episodes and other inflammatory conditions that often complicate the course of these diseases may further promote hepcidin synthesis through increased cytokine production leading to even lower iron availability and a vicious circle of worsening anemia.


Assuntos
Anemia/sangue , Anemia/metabolismo , Ferro/sangue , Hormônios Peptídicos/metabolismo , Citocinas/metabolismo , Feminino , Hepcidinas/química , Homeostase , Humanos , Inflamação , Masculino , Modelos Biológicos
7.
J Biol Regul Homeost Agents ; 28(1): 1-15, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24750786

RESUMO

The high malignancy of glioblastoma has been recently attributed to the presence, within the tumor, of glioblastoma stem cells (GSC) poorly responsive to chemo- and radiotherapy. Here, the potential employment of metformin and arsenic trioxide (ATO) in glioblastoma therapy is discussed focusing on their effects on GSC. Metformin exerts anticancer effects by primarily blocking the pivotal LKB1/AMPK/mTOR/S6K1 pathway-dependent cell growth, induces selective lethal effects on GSC by impairing the GSC-initiating spherogenesis and inhibits the proliferation of CD133+ cells, while having a low or null effect on differentiated glioblastoma cells and normal human stem cells. Metformin and ATO induce autophagy and apoptosis in glioma cells by inhibiting and stimulating the PI3K/Akt and the mitogen-activated protein kinase pathways, respectively. Both drugs promote differentiation of GSC into non-tumorigenic cells. In this regard, metformin acts via activation of the AMPK-FOXO3 axis, whereas ATO blocks the interleukin 6-induced promotion of STAT3 phosphorylation. Blood-brain barrier, easily crossed by metformin but not by ATO, undergoes important glioblastoma-induced alterations that increase its permeability, thus allowing ATO to distribute more into the glioblastoma bulk than in the normal brain parenchyma. A prompt clinical assessment of metformin and ATO in glioblastoma patients would represent a valid attempt to improve their survival.


Assuntos
Antineoplásicos/farmacologia , Arsenicais/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Metformina/farmacologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Óxidos/farmacologia , Quinases Proteína-Quinases Ativadas por AMP , Proteínas Quinases Ativadas por AMP/antagonistas & inibidores , Animais , Trióxido de Arsênio , Neoplasias Encefálicas/patologia , Resistencia a Medicamentos Antineoplásicos , Glioblastoma/patologia , Humanos , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Tolerância a Radiação
8.
J BUON ; 17(3): 417-21, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23033275

RESUMO

Paraneoplastic syndromes (PNS) are remote effects of cancer that are, by definition, caused neither by invasion of the tumor or its metastases nor by infection, ischemia, metabolic and nutritional deficits, surgery or other forms of tumor treatment. The purpose of the current review was to present the challenging elements of differential diagnosis in oncology, as they may represent the main clinical problem in a patient diagnosed with cancer, even though the complete knowledge of both their clinical aspects and pathogenesis remain quite poor. This review focuses on the paraneoplastic syndromes related to dermatology and rheumatology, as the most frequent manifestations come from connective tissues that might determine a patient to ask for consultation by a general practitioner.


Assuntos
Doenças do Tecido Conjuntivo/etiologia , Síndromes Paraneoplásicas/etiologia , Animais , Humanos , Doenças Reumáticas/etiologia , Dermatopatias/etiologia
9.
J BUON ; 17(2): 230-6, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22740198

RESUMO

Colorectal cancer is the fourth most common cancer in men and the third most common cancer in women worldwide. The partial failure of classic therapeutic options makes scientists to doubt the efficacy of systemic treatments in targeting the essential cell populations and achieving cure as a final goal. Overgrowing data suggest that cancer is a disease closely linked to stem cells (SCs). It is well known that the first identification of cancer stem-like cells in acute myeloid leukaemia was soon followed by similar results in solid malignancies, including colorectal cancer, and the classic model for colon carcinogenesis supports the development of sudden mutations that will lead to the activation or inactivation of certain oncogenes or tumor suppressors. Thus, this process may go on for years before the first symptoms and the only cells able to withstand for many years, avoid apoptosis and have a high regenerative capacity are the progenitor cells found at the lower part of colon crypts. A more profound study of the mechanisms and molecular signalling pathways that control the basic characteristics of SCs, such as asymmetrical division or self-renewal, may help comprehend the basic mechanisms of cancer genesis and progression. This will result in the development of new therapeutic agents that may target chemoresistant cell populations and improve the therapeutic results. In the current review we point out the importance of cancer stem-like cells in colorectal oncology from a pathologist's point of view, stating the obvious correlation between histology, embryology and surgical pathology.


Assuntos
Neoplasias Colorretais/patologia , Neoplasias Colorretais/terapia , Células-Tronco Neoplásicas/patologia , Feminino , Humanos , Masculino
10.
Exp Oncol ; 34(1): 17-24, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22453143

RESUMO

OBJECTIVES: Metformin, the most used oral antidiabetic drug for the treatment of type 2 diabetus mellitus, has proved encouraging results when used in the treatment of various types of cancer such as triple-negative breast cancer. Despite compelling evidence of a role of metformin as an anticancer drug, the mechanisms by which metformin exerts its oncostatic actions are not fully understood yet. Therefore, we tried to bring new insights by analyzing the anti-neoplastic effect of metformin for hepatocellular carcinoma-derived stem-like cells treated with conventional combination chemotherapy. METHODS: Cancer stem-like cells previusly isolated from a hepatocellular carcinoma biopsy were treated with metformin, PIAF chemotherapy regimen and the combination of these two protocols. Measurements of lipid peroxidation, reduced glutathione, fluorescein diacetate and proliferation rates were determined, apart from the autophagy assay and apoptosis determination by chip flow cytometry. RESULTS: Metformin alone and especially metformin in association with PIAF increases oxidative stress within the cells by increasing the levels of lipid peroxids as well as decreasing the levels of reduced glutathione. The MTT cell proliferation assay showed decreased prolife-ration rates for the arm treated with metformin and with the combination of drugs in comparison with the control arm, proving high correlation with the oxidative stress results. The autophagy assay and determination of apoptosis by chip flow cytometry confirmed the results obtained in the previous assays. CONCLUSION: Metformin could be used in chemotherapy treatments to induce reactive oxygen species and increase the cytostatics effects within the tumor cell. Still, further experiments must be carried out on murine models before we can move on and use this drugs in the adjuvant setting for unresectable primary liver cancer.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Metformina/farmacologia , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Carcinoma Hepatocelular/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cisplatino/farmacologia , Doxorrubicina/farmacologia , Fluoruracila/farmacologia , Glutationa/metabolismo , Humanos , Interferon-alfa/farmacologia , Neoplasias Hepáticas/tratamento farmacológico
11.
Rom J Morphol Embryol ; 52(3 Suppl): 999-1004, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22119816

RESUMO

BACKGROUND AND AIM: The progress made in the last few years have managed to come up withy the possibility of using different stem cell types in an endeavor to correct the alterations that appear in different degenerative diseases. The pancreas, an organ with extremely low regenerative capacity, both for the endocrine and for the exocrine component, is an organ perfect for cell therapy in the hope of restoring its function and cure diabetes mellitus or chronic pancreatitis. One main issue in the stem cell transplantation problem is represented by the influence of the cellular niche, formed by completely differentiated cells, on the phenotype and function of the transplanted cells. In this study, we challenge current knowledge in the field by evaluating the influence of exocrine pancreatic cells on placental stem-like cells using the co-culture technique. METHODS: In our experiments, we used two different protocols in which adult pancreatic cells were cultured together with mesenchymal stem cells isolated from human placenta. In the case of the first protocol, we seeded pancreatic cells on a pre-adhered single-cell layer of mesenchymal stem cells and in the second one, the seeding of two cell populations in suspension was done at the same time, after passage. During the experiment, we evaluated the alteration of the morphology of the placental cells using and inverted phase microscope and reverse transcriptase-PCR. RESULTS AND CONCLUSIONS: Based on morphology, in both cases the interaction between epithelial pancreatic cells and placental ones have determined a change in phenotype from mesenchymal to epithelial-like. Taking into consideration the gene expression, placental stem cells have maintained pluripotency gene expression throughout the study. They also expressed pancreatic amylase. These experiments bring out the plasticity of placental stem cells, the cell microenvironment with a decisive part in phenotype and the level of gene expression. The results obtained in vitro can bring a new picture on the effects of the pancreatic stem cell niche.


Assuntos
Técnicas de Cocultura/métodos , Pâncreas Exócrino/citologia , Células-Tronco/citologia , Adulto , Biomarcadores/metabolismo , Agregação Celular , Diferenciação Celular/genética , Feminino , Regulação da Expressão Gênica , Humanos , Mesoderma/citologia , Pâncreas Exócrino/metabolismo , Placenta/citologia , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/metabolismo , Reação em Cadeia da Polimerase , Gravidez , Células-Tronco/metabolismo
12.
Rom J Morphol Embryol ; 52(3 Suppl): 1005-10, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22119817

RESUMO

Embryonic stem cells have the ability to remain undifferentiated and proliferate in vitro while maintaining the potential to differentiate into derivatives of all three embryonic germ layers. The aim of the present study was to establish mouse ES lines from blastocyst stage embryos obtained after CD1/EGFP mice superovulation. We isolated, cultured and determined the characteristics of mouse embryonic stem cells in early passages, which were first described by Evans M and Kaufman M. Therefore, we evaluated the morphological criteria for the approval of ES cells in early expansion stage. Two cell lines were isolated (CDE1 and CDE2) and analyzed. They showed similar characteristics to those reported earlier for blastocyst-derived ES cell lines.


Assuntos
Blastocisto/citologia , Técnicas de Cultura de Células/métodos , Linhagem Celular/citologia , Células-Tronco Embrionárias/citologia , Fosfatase Alcalina/metabolismo , Animais , Blastocisto/metabolismo , Diferenciação Celular/genética , Forma Celular , Ensaio de Unidades Formadoras de Colônias , Corpos Embrioides/citologia , Corpos Embrioides/metabolismo , Células-Tronco Embrionárias/enzimologia , Células Alimentadoras/citologia , Feminino , Proteínas de Fluorescência Verde/metabolismo , Imuno-Histoquímica , Camundongos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
13.
J BUON ; 16(3): 409-13, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22006741

RESUMO

One of the main topics of the annual meeting of the American Society for Clinical Oncology in 2011 were the results presented on breast cancer chemotherapy and concomitant administration of the oral antidiabetic metformin. The overall agreement was that current evidence is just enough to dramatically change the clinical practice of oncology, and in our case, brain cancer treatment, and that further research is needed to address the relationship between diabetes, metabolism, insulin analogues and neoplasia. Still, it is very interesting to explore the potentially beneficial effects of metformin in glioma chemo/immunotherapy and wait for results in the clinic. In the current paper we present the cell and molecular aspects of the metabolic syndrome, metformin administration and cancer chemotherapy, with a special emphasis in neuro-oncology, since brain tumors are usually devastating diseases with an extremely high mortality within two years of diagnosis even when surgical, radiotherapeutic and chemotherapeutic interventions are applied.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Síndrome Metabólica/complicações , Metformina/uso terapêutico , Proteínas Quinases Ativadas por AMP/fisiologia , Animais , Transportador de Glucose Tipo 3/fisiologia , Glutationa/metabolismo , Humanos , Espécies Reativas de Oxigênio/metabolismo
14.
J BUON ; 16(2): 282-9, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21766499

RESUMO

PURPOSE: Glioblastoma multiforme (GBM) remains one of the most devastating diseases known to man and affects more than 17,000 patients in the United States alone every year. This malignancy infiltrates the brain early in its course and makes complete neurosurgical resection almost impossible. Recent years have brought significant advances in tumor biology, including the discovery that many cancers, including gliomas, appear to be supported by cells with stem-like properties. In the current study we have investigated the effects of combining metformin with the standard treatment-of-care, as this drug, already used in the treatment of diabetes mellitus, has shown surprising results in the treatment of breast cancer, being also associated with lower mortality in several other malignancies. METHODS: The subjects of the current study were 8 patients with newly diagnosed high-grade gliomas, operated at the Department of Neurosurgery - Clinical University Emergency Hospital, Cluj Napoca. Tumor tissue cultures were established and characterized using immunofluorescence microscopy and PCR analysis and the sensitivity to metformin, epidermal growth factor (EGF) and temozolomide (TMZ) was tested. Microvascular density (MVD) assay was performed on the tumor samples. RESULTS: Seven of the 8 cases had a positive correlation between the number of endothelial cells, the phenotype of isolated tumor cells and the response to adjuvant chemoradiotherapy. The isolated tumor cells had a stem-like behavior, being resistant to conventional drugs. In most cases there was no statistical significant difference between TMZ alone and TMZ plus EGF arms, but there was a important difference between TMZ alone and TMZ plus metformin arms in 6 of the cases. CONCLUSION: New drugs and targeted molecular therapies are important for future therapeutics, but sometimes we must not exclude drugs already used in the clinic that might have remarkable results. Such is the case of metformin, a drug used for decades in the treatment of type 2 diabetes mellitus that has proven to enhance the effect of TMZ in the treatment of breast cancer and, starting with this paper, of brain cancer.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Dacarbazina/análogos & derivados , Glioma/tratamento farmacológico , Glioma/patologia , Metformina/uso terapêutico , Adulto , Idoso , Antineoplásicos Alquilantes/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica , Western Blotting , Proliferação de Células/efeitos dos fármacos , Quimioterapia Adjuvante , Dacarbazina/uso terapêutico , Feminino , Humanos , Hipoglicemiantes/uso terapêutico , Técnicas Imunoenzimáticas , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Taxa de Sobrevida , Temozolomida , Resultado do Tratamento , Células Tumorais Cultivadas , Organização Mundial da Saúde
15.
J BUON ; 16(1): 16-23, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21674845

RESUMO

High grade gliomas, the most frequent and most malignant brain cancers, grow rapidly and infiltrate the cerebrospinal axis causing deficits in cognition, mobility, balance or speech and are typically resistant to radiation and chemotherapy. Despite recent progress, WHO grade III and IV gliomas still represent a great challenge in oncology, with overall poor outcomes and inevitable lethality. While radiotherapy and temozolomide are considered the standard first-line approach for therapy of newly diagnosed malignant gliomas, the treatment protocols for recurrent tumors remain ill-defined. Increasing evidence suggests that tumors of the central nervous system are derived from proliferatively active neural stem cells residing in defined neuropoietic niches of the adult brain. These cancer stem cells, also identified in other tumors, provide a reservoir of cells with self-renewal capabilities, can maintain the tumor by generating differentiated non-stem tumor cells and are responsible for recurrences after ablative neurosurgical therapy and chemoradiotherapy. The only way to successfully control recurrent malignant gliomas and even hope for a cure in the future is by combining standard chemotherapy with immunotherapy. Despite the apparent improvements of current treatments, it should be realized that the characteristic brain tumor niche may provide recurrent gliomas an "escape mechanism" from anticancer treatments. Thus, the use of targeted molecular therapy drugs may effectively inhibit or at least slow down cancer stem cell proliferation and stop the brain microenvironment from allowing furtive invasion and proliferation of highly aggressive malignant gliomas.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Glioma/tratamento farmacológico , Terapia de Alvo Molecular , Células-Tronco Neoplásicas/efeitos dos fármacos , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/epidemiologia , Neoplasias Encefálicas/fisiopatologia , Resistencia a Medicamentos Antineoplásicos , Glioma/diagnóstico , Glioma/epidemiologia , Glioma/fisiopatologia , Humanos , Transdução de Sinais
16.
Rom J Intern Med ; 49(4): 319-25, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22568277

RESUMO

Over the past years medicine has undergone intensive changes, evolving from classical semiology and internal medicine to individualized treatments, based on recent breakthroughs in immunology and genetics. This concept has had a profound impact in all medical specialties and as a consequence pharmacology and various treatment plans will be based on monoclonal antibodies and targeted cell therapies. One such target is the SDF-1-CXCR4 axis bacause it plays a critical role in many physiological processes that involve cell migration and cell fate decisions, ranging from stem cell homing, angiogenesis and neuronal development to immune cell trafficking. The chemokine receptor CXCR4 and its ligand stromal cell-derived factor 1alpha are also implicated in various pathological conditions, including metastatic spread and HIV infection. In this review, we present the concept that the SDF-1-CXCR4 axis is a master regulator of trafficking of both normal and cancer stem cells, based on the growing evidence that it plays a pivotal role in the regulation of trafficking of normal hematopoietic stem cells and their homing to the bone marrow. Because most malignancies originate in the progenitor cell compartment, cancer stem cells also express CXCR4 on their surface and migrate to organs that highly express SDF-1. Hence, we postulate that the metastasis of cancer stem cells and trafficking of normal stem cells involve similar mechanisms, which may be regulated by several small molecules related to inflammation. Consequently, strategies aimed at modulating the SDF-1-CXCR4 axis could have important clinical applications in both tissue engineering and in clinical hematology and oncology to inhibit metastasis of cancer stem cells.


Assuntos
Quimiocina CXCL12/metabolismo , Terapia de Alvo Molecular , Neoplasias , Células-Tronco Neoplásicas/metabolismo , Receptores CXCR4/metabolismo , Anticorpos Monoclonais/uso terapêutico , Diferenciação Celular , Movimento Celular , Previsões , Humanos , Inflamação/metabolismo , Ligantes , Terapia de Alvo Molecular/métodos , Terapia de Alvo Molecular/tendências , Metástase Neoplásica , Neoplasias/metabolismo , Neoplasias/patologia , Neoplasias/terapia , Neuroimunomodulação , Transdução de Sinais
17.
Rom J Intern Med ; 49(3): 189-96, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22471100

RESUMO

Although the treatment for colorectal cancer has seen considerable progress during the past few years, the mortality associated with this type of tumor remains high. This article presents the existing methods of treatment, focusing on the new treatments made possible by the advances in the field of normal and tumor stem cells. Starting from the normal architecture of the colon and the properties of the cells identified in it, we sought to present a few notions concerning these cells which have a direct relevance for both pathology and treatment. The manner in which they divide (symmetrically or asymmetrically) as well as the molecules which control their circulation through the body are just a few examples which are likely to influence the treatment of colorectal cancer in the future.


Assuntos
Neoplasias Colorretais/patologia , Células-Tronco , Colo/citologia , Neoplasias Colorretais/terapia , Humanos , Terapia de Alvo Molecular , Metástase Neoplásica , Células-Tronco Neoplásicas , Reto/citologia
18.
Rom J Morphol Embryol ; 51(4): 733-8, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21103634

RESUMO

BACKGROUND AND PURPOSE: For the past few years, in an attempt to find new sources of cells that may be used in cell therapy, numerous researchers have highlighted the particular properties of mesenchymal stem cells. Mesenchymal stem cells can be isolated from adult tissues such as the bone marrow or adipose tissue, but also from other organs such as the human placenta. Our study focuses adult stem cells isolated from the chorionic villi in an attempt to differentiate them into islets of Langerhans in order to study their differentiation potential, as a future background for cell therapy. EXPERIMENTAL DESIGN: Full-term placentas were prelevated from volunteer women that have just delivered a normal pregnancy. After a mechanical fragmentation of the placenta, the chorion fragments are transferred in a dish with dispase before the enzyme is inactivated using fetal calf serum. The cell suspension is filtered in order to obtain a single-cell suspension. After the adherence of the first cells, the proliferation rate increased progressively and cell morphology is kept the same for several passages. In order to correctly differentiate placental stem cells into glucagon-secreting cells, we used a culture method on a scaffold with sequential exposure to different growth factors. The underlying substrate used contained type IV collagen, chytosan, Matrigel and laminin. Molecular biology techniques were carried out to investigate the gene expression of the stem cells. RESULTS: Our results show that exendin-4 is able to induce the differentiation of placental stem cells into glucagon-secreting cells. We also notice the absence of the insulin gene, a conclusion that may be explained by the fact that our phenotype is a partial one, incomplete, closer to islet cell progenitors than to insulin-producing progenitors. CONCLUSIONS: The identification of the placenta as a valid source for stem cells has important practical advantages because it is easily accessible, it raises no ethical issues and cells are easily to isolate in a large enough number to use. The future knowledge and manipulation of the signaling pathways that determines the dramatic phenotype shift may provide the basis for efficient cell differentiation, with great impact on regenerative medicine and tissue engineering.


Assuntos
Células-Tronco Adultas/citologia , Células Secretoras de Glucagon/citologia , Placenta/citologia , Adulto , Células-Tronco Adultas/fisiologia , Sequência de Bases , Diferenciação Celular , Separação Celular , Vilosidades Coriônicas/anatomia & histologia , Primers do DNA/genética , Feminino , Expressão Gênica , Glucagon/genética , Glucagon/metabolismo , Células Secretoras de Glucagon/fisiologia , Humanos , Técnicas In Vitro , Insulina/genética , Gravidez
19.
J BUON ; 15(3): 583-91, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20941832

RESUMO

PURPOSE: Brain tumors are the leading cause of cancer mortality in children and remain incurable despite advances in surgery and adjuvant therapies. The failure of malignant gliomas to respond to conventional treatment reflects the unique biology of these tumors, linked to a small population of stem-like precursors. This study describes the characteristics of stem cells isolated from glioblastoma multiforme (GM) and gives insight into the mechanism of brain tumorigenesis. METHODS: Tumor stem-like precursors were identified from primary human GM-derived cell culture using immunocytochemistry and reverse transcription polymerase chain reaction (RT-PCR). Cells were cultured in vitro in stem cell medium supplemented with growth factors and then the capacity of the surviving stem-like precursors to form tumor spheres and to continue to proliferate after chemoradiotherapy were tested. RESULTS: The tumor cells expressed the cellular markers CD133, CD105, CD90, Nanog, Oct 3/4, CXCR4, nestin, glial fibrillary acidic protein (GFAP), neurofilament protein (NF) and human glyceraldehyde 3-phosphate dehydrogenase (GAPDH). Cells also displayed a high proliferative potential despite chemotherapy and irradiation and also had the ability to form spheroids in suspension. CONCLUSION: High grade gliomas contain stem-like precursors, which exhibit neural stem cell properties with tumorigenicity, establishing a novel developmental paradigm in the study of brain carcinogenesis and providing a powerful tool to develop patient-tailored therapy for this devastating disease.


Assuntos
Neoplasias Encefálicas/patologia , Glioblastoma/patologia , Células-Tronco Neoplásicas/fisiologia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/radioterapia , Feminino , Proteína Glial Fibrilar Ácida/análise , Glioblastoma/tratamento farmacológico , Glioblastoma/radioterapia , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Células-Tronco Neoplásicas/química , Fator 3 de Transcrição de Octâmero/análise
20.
Rom J Morphol Embryol ; 51(3): 427-35, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20809016

RESUMO

Similar to normal organs arising from normal stem cells, cancers can be viewed as organs composed of heterogeneous cellular populations arising from cancer cells with indefinite proliferation abilities. The continuous malignant progression is maintained by the proliferation of cancer stem cells and not the progeny that undergo limited proliferation before terminally differentiating. Effective therapy must eradicate malignant cells with unlimited clonogenic expansion within the primary tumor bulk. Thus, resolving both the specific cell of origin for prostate cancer and the interactions between the cells and the surrounding microenvironment within the cancer stem cell niche are crucial to appropriately define rational targets for therapeutic intervention and cure prostate cancer.


Assuntos
Comunicação Celular , Lesões Pré-Cancerosas/patologia , Neoplasias da Próstata/patologia , Resistencia a Medicamentos Antineoplásicos , Humanos , Masculino , Metástase Neoplásica , Células Neoplásicas Circulantes/patologia , Células-Tronco Neoplásicas/patologia , Neoplasias da Próstata/embriologia , Neoplasias da Próstata/epidemiologia , Neoplasias da Próstata/terapia , Nicho de Células-Tronco/patologia
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