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1.
BMC Cancer ; 15: 352, 2015 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-25935541

RESUMO

BACKGROUND: Tumour relapse is recognized to be the prime fatal burden in patients affected by head and neck squamous cell carcinoma (HNSCC), but no discrete molecular trait has yet been identified to make reliable early predictions of tumour recurrence. Expression of cell surface proteoglycans (PGs) is frequently altered in carcinomas and several of them are gradually emerging as key prognostic factors. METHODS: A PG expression analysis at both mRNA and protein level, was pursued on primary lesions derived from 173 HNSCC patients from whom full clinical history and 2 years post-surgical follow-up was accessible. Gene and protein expression data were correlated with clinical traits and previously proposed tumour relapse markers to stratify high-risk patient subgroups. RESULTS: HNSCC lesions were indeed found to exhibit a widely aberrant PG expression pattern characterized by a variable expression of all PGs and a characteristic de novo transcription/translation of GPC2, GPC5 and NG2/CSPG4 respectively in 36%, 72% and 71% on 119 cases. Importantly, expression of NG2/CSPG4, on neoplastic cells and in the intralesional stroma (Hazard Ratio [HR], 6.76, p = 0.017) was strongly associated with loco-regional relapse, whereas stromal enrichment of SDC2 (HR, 7.652, p = 0.007) was independently tied to lymphnodal infiltration and disease-related death. Conversely, down-regulated SDC1 transcript (HR, 0.232, p = 0.013) uniquely correlated with formation of distant metastases. Altered expression of PGs significantly correlated with the above disease outcomes when either considered alone or in association with well-established predictors of poor prognosis (i.e. T classification, previous occurrence of precancerous lesions and lymphnodal metastasis). Combined alteration of all three PGs was found to be a reliable predictor of shorter survival. CONCLUSIONS: An unprecedented PG-based prognostic portrait is unveiled that incisively diversifies disease course in HNSCC patients beyond the currently known clinical and molecular biomarkers.


Assuntos
Antígenos/metabolismo , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas/metabolismo , Neoplasias de Cabeça e Pescoço/metabolismo , Recidiva Local de Neoplasia/metabolismo , Proteoglicanas/metabolismo , Adulto , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/cirurgia , Proteoglicanas de Sulfatos de Condroitina/metabolismo , Feminino , Neoplasias de Cabeça e Pescoço/mortalidade , Neoplasias de Cabeça e Pescoço/cirurgia , Humanos , Estimativa de Kaplan-Meier , Masculino , Proteínas de Membrana/metabolismo , Pessoa de Meia-Idade , Boca/metabolismo , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/prevenção & controle , Modelos de Riscos Proporcionais , Sindecana-2/metabolismo , Resultado do Tratamento
2.
J Craniomaxillofac Surg ; 43(2): 208-13, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25530302

RESUMO

The chance of developing a neck nodal metastasis after initial treatment of oral squamous cell carcinoma varies from 12.4% to 62%. Despite being the main reason for cancer-related mortality, nodal metastases are still rarely subjected to molecular analyses, and our knowledge of the clonal heterogeneity of multiple lesions within the same patient is limited. The aim of the present study was to evaluate the relationship between primary oral cancer and lymph node metastasis in a series of patients with synchronous and metachronous metastases by 2 clonality tests: mt-DNA and TP53 sequence analysis. The study population consisted of 10 consecutive patients. Data identified in this study demonstrate that our assay based on next-generation analysis of TP53 and mt-DNA is simple, is reliable, allows high throughput, and may be applied to retrospective cases. The combination of mt-DNA and TP53 data analysis helped us to evaluate more precisely and consistently the genetic relationship among different tumor clones.


Assuntos
Carcinoma de Células Escamosas/patologia , DNA Mitocondrial/genética , Genes p53/genética , Metástase Linfática/patologia , Neoplasias Bucais/patologia , Análise de Sequência de DNA/métodos , Idoso , Carcinoma in Situ/genética , Carcinoma in Situ/patologia , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/secundário , Células Clonais/metabolismo , Células Clonais/patologia , Éxons/genética , Feminino , Heterogeneidade Genética , Humanos , Neoplasias Pulmonares/patologia , Metástase Linfática/genética , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/genética , Mutagênese Insercional/genética , Esvaziamento Cervical/métodos , Estadiamento de Neoplasias , Segunda Neoplasia Primária/patologia , Mutação Puntual/genética , Deleção de Sequência/genética , Neoplasias da Língua/genética , Neoplasias da Língua/patologia , Neoplasias da Traqueia/secundário
3.
Head Neck ; 36(1): 94-100, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23633084

RESUMO

BACKGROUND: Histological and clinical criteria are generally used to differentiate second primary tumors (SPTs) from local recurrences. The purpose of the present study was to apply mitochondrial DNA (mtDNA) D-loop analysis to differentiate SPTs from local recurrences and to validate the clinical classification. METHODS: The study population consisted of 20 consecutive patients presenting multiple oral neoplastic lesions for a total of 25 paired lesions. The mtDNA D-loop analysis was performed by direct sequencing and phylogenetic clusterization. RESULTS: Agreement between mtDNA analysis and clinical classification was found in 19 cases. Discrepancies arose in 6 cases in which the clinical criteria based only on the spatial or temporal distance of the second lesion from the index tumor had led to a diagnosis of SPT (2 cases) or local recurrence (4 cases). CONCLUSION: The present data highlight the value of mtDNA analysis in establishing the clonal relationship between the index tumor and the second neoplastic lesion.


Assuntos
Carcinoma de Células Escamosas/genética , DNA Mitocondrial/genética , Predisposição Genética para Doença , Neoplasias Bucais/genética , Recidiva Local de Neoplasia/genética , Segunda Neoplasia Primária/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Estudos de Coortes , Análise Mutacional de DNA , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/patologia , Neoplasias Bucais/cirurgia , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/cirurgia , Segunda Neoplasia Primária/patologia , Segunda Neoplasia Primária/cirurgia , Estudos Retrospectivos , Medição de Risco
4.
Int J Surg Pathol ; 22(1): 55-62, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24326825

RESUMO

Lymph node metastasis (LNm), local recurrence (LR), and second primary tumor (SPT) after primary surgery for oral squamous cell carcinoma (OSCC) have been considered poor prognostic entities in terms of survival rate. The purpose of this study was to identify the clinicopathologic parameters significantly related to LNm, LR, and SPT. Records from 180 patients who underwent radical surgery for OSCC were retrospectively reviewed. Perineural invasion was significantly related to LNm (18% vs 8%) and LR (15% vs 5%), while the status of the surgical margin (10% in case of clear margins, 18% close margins, and 24% involved margins), namely epithelial precursor lesions (43%) was an independent factor influencing SPT. Perineural invasion proved a good prognostic factor for early events, either LNm or LR, while a surgical margin width less than 5 mm or with epithelial precursor lesions may be considered a risk factor for late events such as SPT.


Assuntos
Carcinoma de Células Escamosas/patologia , Metástase Linfática/patologia , Neoplasias Bucais/patologia , Recidiva Local de Neoplasia/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/cirurgia , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/mortalidade , Neoplasias Bucais/cirurgia , Recidiva Local de Neoplasia/mortalidade , Prognóstico , Estudos Retrospectivos
5.
Artigo em Inglês | MEDLINE | ID: mdl-22819335

RESUMO

Patients with head and neck squamous cell carcinoma (SCC) are at risk of developing additional tumors in the head and neck. The detection of a late lymph node metastasis poses a problem to the clinician: it could be a delayed regional metastasis or a new metastasis from a yet unknown second primary tumor. Differentiation between metastasis and recurrence of primary tumors versus second primary tumor may be difficult because all lesions have the histologic appearance of SCC. Differentiation between these possibilities, however, carries important differences in therapeutic and prognostic consequences. In the following case report we present an unusually late regional lymph node metastasis in a patient who was treated 4 years earlier for an SCC in the inferior alveolar ridge. The purpose of the present study was to apply mitochondrial DNA D-loop analysis to assess the clonal relationship between oral tumor and node metastasis.


Assuntos
Carcinoma de Células Escamosas/secundário , DNA Mitocondrial/análise , Linfonodos/patologia , Neoplasias Mandibulares/secundário , Neoplasias Primárias Desconhecidas/patologia , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Feminino , Humanos , Metástase Linfática/diagnóstico , Imageamento por Ressonância Magnética , Masculino , Neoplasias Mandibulares/genética , Neoplasias Mandibulares/patologia , Pessoa de Meia-Idade , Neoplasias Primárias Desconhecidas/genética
6.
Hum Pathol ; 44(11): 2400-9, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24007691

RESUMO

The purpose of this retrospective study was to investigate the role of galectin-3 (LGALS3) expression in predicting the recurrence and the progression potential of prolactin (PRL) and adrenocorticotropic hormone (ACTH)-producing pituitary adenomas and its correlation with the RUNX1 and RUNX2 transcription factors involved in the regulation mechanism of LGALS3 expression. Clinical, neuroradiologic, and follow-up data from 92 pituitary adenomas, including 59 PRL cell adenomas and 33 ACTH-functioning pituitary adenomas, were collected. The LGALS3 expression was analyzed by both immunohistochemistry and quantitative real time-polymerase chain reaction, whereas RUNX1 and RUNX2 were analyzed by quantitative real time-polymerase chain reaction only. The data obtained indicated that invasive growth with suprasellar extension, Ki-67 labeling index, and LGALS3 immunohistochemical and/or LGALS3 messenger RNA levels are the most important histologic features for assessing a high risk of progression or recurrence of PRL- and ACTH-functioning pituitary adenomas. Multivariate Cox regression analysis assessed LGALS3 immunohistochemical positivity in at least 30% of neoplastic cells and/or LGALS3 messenger RNA positivity (P < .001) as strong predictive factors of recurrence/tumor progression followed by a Ki-67 labeling index greater than 3% (P = .019) in the 81 cases in which follow-up data were available. In addition, a significant correlation between LGALS3 and RUNX1 expression levels (P = .0435) was found. This retrospective immunohistochemical and molecular study demonstrated that LGALS3 expression appeared to be a predictive factor of the aggressive behavior of PRL- and ACTH-functioning pituitary adenomas, and its expression was correlated with RUNX1 expression levels.


Assuntos
Adenoma/patologia , Biomarcadores Tumorais/metabolismo , Galectina 3/metabolismo , Recidiva Local de Neoplasia/patologia , Neoplasias Hipofisárias/patologia , Prolactinoma/metabolismo , Adenoma/metabolismo , Adolescente , Hormônio Adrenocorticotrópico/metabolismo , Adulto , Idoso , Proteínas Sanguíneas , Criança , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Progressão da Doença , Intervalo Livre de Doença , Feminino , Galectina 3/genética , Galectinas , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/metabolismo , Neoplasias Hipofisárias/metabolismo , Prognóstico , Prolactina/genética , Estudos Retrospectivos , Adulto Jovem
7.
Int J Surg Pathol ; 21(2): 133-41, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23349470

RESUMO

Metastases to cervical lymph nodes (LNs) are an important independent adverse indicator in the prognosis of oral squamous cell carcinoma (OSCC). An accurate evaluation of molecular patterns favoring the metastatic process can be helpful in predicting cases of OSCC with elevated probability of early or late metastases and, moreover, in planning the proper therapeutic procedures before surgery. To this end, immunohistochemical expressions of both E-cadherin and podoplanin were evaluated on preoperative incisional biopsies of OSCC from 102 patients. The probability to have or develop metastases was very low when high E-cadherin expression was found in a preoperative sample or when a low podoplanin expression was found. Therefore, because of the strong association with LN metastases, high E-cadherin/low podoplanin immunohistochemical expression should also be assessed on preoperative incisional biopsies as a useful tool for evaluating the probability of early or late LN metastases of OSCCs.


Assuntos
Caderinas/biossíntese , Carcinoma de Células Escamosas/metabolismo , Glicoproteínas de Membrana/biossíntese , Neoplasias Bucais/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Biópsia , Caderinas/análise , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Feminino , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Metástase Linfática/patologia , Masculino , Glicoproteínas de Membrana/análise , Pessoa de Meia-Idade , Neoplasias Bucais/mortalidade , Neoplasias Bucais/patologia
8.
Hum Pathol ; 44(7): 1310-9, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23337025

RESUMO

Nearly 80% of well-differentiated in situ duct carcinomas (g1 DCIS) have been shown to be multicentric (multilobar) lesions, while most in situ poorly differentiated duct carcinomas (g3 DCIS) were unifocal (unilobar) lesions. Here we present a clonality study of 15 cases of DCIS, all showing multiple foci. Twelve of these cases were associated with an invasive duct carcinoma. Fifteen cases of female breast cancer patients all showing multiple DCIS foci (5 g1 DCIS, 5 g2 DCIS, 5 g3 DCIS) were randomly selected and histologically studied using large histological sections. Care was taken to laser-microdissect DCIS foci that were most distantly located from one another in the same large section, and pertinent cells were genetically studied. Invasive duct carcinoma and ipsilateral lymph node metastases and/or contralateral lesions, whenever present, were additionally microdissected. DNA of neoplastic cells was purified, and the mtDNA D-loop region was sequenced. Genetic distance of different foci from the same case was visualized by phylogenetic analyses using the neighbor-joining method. Patients ranged in age from 36 to 87 years (mean 65.1). All 9 cases of widely spread DCIS were not clonal. Four of 6 cases that showed multiple adjacent foci were clonally related on mtDNA analysis. In the present series, 11/15 DCIS appeared as multiple synchronous primary breast tumors, genetically not related to one another. The present data enhance the view that breast can also show the field cancerization phenomenon, paralleling what has already been proposed in other organs.


Assuntos
Neoplasias da Mama/genética , Carcinoma Ductal de Mama/genética , Carcinoma Intraductal não Infiltrante/genética , Transformação Celular Neoplásica/genética , Regulação Neoplásica da Expressão Gênica , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Carcinoma Intraductal não Infiltrante/patologia , Células Clonais , Progressão da Doença , Feminino , Perfilação da Expressão Gênica , Predisposição Genética para Doença/genética , Humanos , Pessoa de Meia-Idade , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/patologia
9.
Tumori ; 98(3): 79e-81e, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22825524

RESUMO

The skin can host metastatic tumors originating from different organs. We report a case of metastatic renal cell carcinoma to the scalp in a 73-year-old man with features very similar to those of thyroid papillary carcinoma. The histogenesis in relation to its structure is discussed.


Assuntos
Carcinoma de Células Renais/diagnóstico , Neoplasias Renais/diagnóstico , Couro Cabeludo/patologia , Neoplasias Cutâneas/diagnóstico , Neoplasias da Glândula Tireoide/diagnóstico , Idoso , Carcinoma Papilar/diagnóstico , Carcinoma de Células Renais/secundário , Diagnóstico Diferencial , Humanos , Neoplasias Renais/patologia , Masculino , Neoplasias Cutâneas/secundário
10.
Int J Mol Sci ; 13(2): 2439-2458, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22408463

RESUMO

In bone engineering, the adhesion, proliferation and differentiation of mesenchymal stromal cells rely on signaling from chemico-physical structure of the substrate, therefore prompting the design of mimetic "extracellular matrix"-like scaffolds. In this study, three-dimensional porous poly-L-lactic acid (PLLA)-based scaffolds have been mixed with different components, including single walled carbon nanotubes (CNT), micro-hydroxyapatite particles (HA), and BMP2, and treated with plasma (PT), to obtain four different nanocomposites: PLLA + CNT, PLLA + CNTHA, PLLA + CNT + HA + BMP2 and PLLA + CNT + HA + PT. Adult bone marrow mesenchymal stromal cells (MSCs) were derived from the femur of orthopaedic patients, seeded on the scaffolds and cultured under osteogenic induction up to differentiation and mineralization. The release of specific metabolites and temporal gene expression profiles of marrow-derived osteoprogenitors were analyzed at definite time points, relevant to in vitro culture as well as in vivo differentiation. As a result, the role of the different biomimetic components added to the PLLA matrix was deciphered, with BMP2-added scaffolds showing the highest biomimetic activity on cells differentiating to mature osteoblasts. The modification of a polymeric scaffold with reinforcing components which also work as biomimetic cues for cells can effectively direct osteoprogenitor cells differentiation, so as to shorten the time required for mineralization.


Assuntos
Regeneração Óssea , Ácido Láctico/química , Células-Tronco Mesenquimais/citologia , Nanocompostos/química , Polímeros/química , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Idoso , Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia , Regeneração Óssea/efeitos dos fármacos , Técnicas de Cultura de Células/instrumentação , Técnicas de Cultura de Células/métodos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Feminino , Regeneração Tecidual Guiada/instrumentação , Regeneração Tecidual Guiada/métodos , Humanos , Ácido Láctico/farmacologia , Masculino , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/fisiologia , Pessoa de Meia-Idade , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Osteoblastos/fisiologia , Osteogênese/efeitos dos fármacos , Poliésteres , Polímeros/farmacologia , Transdução de Sinais/efeitos dos fármacos
11.
Eur Spine J ; 21 Suppl 1: S10-9, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22395304

RESUMO

PURPOSE: Disc degeneration, and associated low back pain, are a primary cause of disability. Disc degeneration is characterized by dysfunctional cells and loss of proteoglycans: since intervertebral tissue has a limited capacity to regenerate, this process is at present considered irreversible. Recently, cell therapy has been suggested to provide more successful treatment of IVD degeneration. To understand the potential of cells to restore IVD structure/function, tissue samples from degenerated IVD versus healthy discs have been compared. METHODS: Discal tissue from 27 patients (40.17 ± 11 years) undergoing surgery for degenerative disc disease (DDD), DDD + herniation and congenital scoliosis, as controls, was investigated. Cells and matrix in the nucleus pulposus (NP) and annulus fibrosus (AF) were characterized by histology. AF- and NP-derived cells were isolated, expanded and characterized for senescence and gene expression. Three-dimensional NP pellets were cultured and stained for glycosaminoglycan formation. RESULTS: Phenotypical markers of degeneration, such as cell clusters, chondrons, and collagen disorganization were seen in the degenerate samples. In severe degeneration, granulation tissue and peripheral vascularization were observed. No correlation was found between the Pfirrmann clinical score and the extent of degeneration. CONCLUSION: The tissue disorganization in degenerate discs and the paucity of cells out of cluster/chondron association, make the IVD-derived cells an unreliable option for disc regeneration.


Assuntos
Degeneração do Disco Intervertebral/metabolismo , Degeneração do Disco Intervertebral/patologia , Disco Intervertebral/metabolismo , Disco Intervertebral/patologia , Adulto , Células Cultivadas , Feminino , Glicosaminoglicanos/metabolismo , Humanos , Deslocamento do Disco Intervertebral/metabolismo , Deslocamento do Disco Intervertebral/patologia , Dor Lombar/metabolismo , Dor Lombar/patologia , Masculino , Pessoa de Meia-Idade , Proteoglicanas/metabolismo , Regeneração , Escoliose/congênito , Escoliose/metabolismo , Escoliose/patologia
12.
Int J Artif Organs ; 34(10): 998-1011, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22161283

RESUMO

PURPOSE: For bone regeneration therapy using stem cells, well-defined ex vivo protocols to expand mesenchymal stromal cells (MSC), as well as assays to show their potential differentiation into the osteogenic lineage, are needed. Aim of this study was to analyze the role of the biochemical osteogenic inducers, i.e. ascorbic acid, dexamethasone, and ß-glycerophosphate, employed in the current protocols for osteogenic differentiation of MSC in vitro, to address the requirements for reliable differentiation systems. METHODS: MSC were isolated from the bone marrow of donors (46-73 years of age) undergoing total hip replacement, and expanded in vitro. At confluence, MSC were cultured under four different conditions: α-MEM plus serum (basal medium or C1), basal medium plus ascorbate (C2), basal medium plus ascorbate and dexamethasone (C3), or basal medium plus ascorbate, dexamethasone and ß-glycerophosphate (C4). Morphology, proliferation, mineralization, alkaline phosphatase, collagen and expression of bone-related genes of MSC under the different media were analyzed at fixed time points. RESULTS: MSC proliferation and the number of colony forming units were increased by ascorbic acid, whereas dexamethasone enhanced the proportion of ALP-positive CFU and was critical for mineral deposition. Runx-2 and type I collagen gene expression decreased along with additive-induced MSC differentiation, i.e. from C1 to C4, while ALP and osteocalcin were differently regulated. CONCLUSION: Our findings support the role of different inducers on the sequential stages of MSC expansion and osteogenic differentiation in vitro, suggesting the addition of DEX following proliferation to ensure mineralization, as an index of in vivo osteogenic potency of human mesenchymal cells.


Assuntos
Ácido Ascórbico/farmacologia , Diferenciação Celular/efeitos dos fármacos , Dexametasona/farmacologia , Glicerofosfatos/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Idoso , Fosfatase Alcalina/metabolismo , Diferenciação Celular/fisiologia , Proliferação de Células , Células Cultivadas , Colágeno Tipo I/metabolismo , Feminino , Humanos , Masculino , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/fisiologia , Pessoa de Meia-Idade , Osteogênese/fisiologia
13.
J Biomater Appl ; 26(4): 465-89, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20566654

RESUMO

Highly porous bioresorbable glass-ceramic scaffolds were prepared via sponge replication method by using an open-cell polyurethane foam as a template and phosphate-based glass powders. The glass, belonging to the P2O5-SiO2-CaO-MgO-Na2O-K2O system, was synthesized by a melting-quenching route, ground, and sieved to obtain powders with a grain size of less than 30 µm. A slurry containing glass powders, polyvinyl alcohol, and water was prepared to coat the polymeric template. The removal of the polymer and the sintering of the glass powders were performed by a thermal treatment, in order to obtain an inorganic replica of the template structure. The structure and properties of the scaffold were investigated from structural, morphological, and mechanical viewpoints by means of X-ray diffraction, scanning electron microscopy, density measurements, image analysis, and compressive tests. The scaffolds exhibited a trabecular architecture that closely mimics the structure of a natural spongy bone. The solubility of the porous structures was assessed by soaking the samples in acellular simulated body fluid (SBF) and Tris-HCl for different time frames and then by assessing the scaffold weight loss. As far as the test in SBF is concerned, the nucleation of hydroxyapatite on the scaffold trabeculae demonstrates the bioactivity of the material. Biological tests were carried out using human bone marrow stromal cells to test the osteoconductivity of the material. The cells adhered to the scaffold struts and were metabolically active; it was found that cell differentiation over proliferation occurred. Therefore, the produced scaffolds, being biocompatible, bioactive, resorbable, and structurally similar to a spongy bone, can be proposed as interesting candidates for bone grafting.


Assuntos
Células da Medula Óssea/citologia , Substitutos Ósseos , Cerâmica , Alicerces Teciduais/química , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Fenômenos Biomecânicos , Células da Medula Óssea/metabolismo , Substitutos Ósseos/síntese química , Substitutos Ósseos/química , Técnicas de Cultura de Células , Diferenciação Celular , Proliferação de Células , Sobrevivência Celular , Cerâmica/síntese química , Cerâmica/química , Força Compressiva , Humanos , Teste de Materiais , Microscopia Eletrônica de Varredura , Osteogênese , Poliuretanos , Porosidade , Solubilidade , Células Estromais/citologia , Células Estromais/metabolismo , Engenharia Tecidual , Difração de Raios X
14.
Bone ; 46(3): 780-8, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19900596

RESUMO

The study was designed to establish the biological basis for the use of autologous bone-marrow stromal cells (MSC) in order to improve the curing opportunities of congenital pseudarthrosis of the tibia (CPT). The investigation was planned by taking into account that the pathophysiology of bone healing mainly depends on the osteogenic potential of the resident cells, although several factors play a crucial role in restoring the normal bone structure. Bone marrow samples were collected from the lesion site (P) and the iliac crest (IC) of 7 patients affected by CPT and type 1 neurofibromatosis (NF1+) and 6 patients affected by CPT without NF1 (NF1-). Four patients without CPT served as control group. Biochemical, functional and molecular assays showed that the ability to generate bone-forming cells was higher in IC-MSC than in P-MSC, but lower in CPT patients than in control group. We evaluated whether host factors, such as autologous serum and the microenvironment surrounding the pseudarthrosis lesion, could impair the osteogenic differentiation of IC-MSC. Autologous serum was less effective than FBS in promoting the IC-MSC differentiation, but the damage was more evident in NF1- than in NF1+ patients. Additionally, the supernatant of osteoblast cultures obtained from bone fragments close to the lesion site favoured the differentiation of IC-MSC in NF1- patients. In summary, our results suggest that MSC transplantation could be a promising strategy for the therapy of CPT. Further studies are warranted to confirm the clinical effectiveness in comparison to standard surgical treatment.


Assuntos
Transplante de Medula Óssea , Pseudoartrose/congênito , Pseudoartrose/cirurgia , Tíbia/anormalidades , Tíbia/cirurgia , Adolescente , Medula Óssea/patologia , Transplante de Medula Óssea/patologia , Células Cultivadas , Criança , Pré-Escolar , Técnicas de Cocultura , Feminino , Humanos , Lactente , Masculino , Pseudoartrose/diagnóstico por imagem , Radiografia , Células Estromais/transplante , Tíbia/diagnóstico por imagem , Transplante Autólogo/patologia , Resultado do Tratamento
15.
Tissue Eng Part C Methods ; 16(3): 511-24, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19686055

RESUMO

Bone marrow is commonly used as a source of adult multipotent mesenchymal stem cells (MSCs), defined for their ability to differentiate in vitro into multiple lineages. The ex vivo-expanded MSCs are currently being evaluated as a strategy for the restoration of function in damaged skeletal tissue, both in cell therapy and tissue engineering applications. The aim of this study was to define gene expression patterns underlying the differentiation of MSCs into mature osteoblasts during the expansion in vitro, and to explore a variety of cell functions that cannot be easily evaluated using morphological, cytochemical, and biochemical assays. Cell cultures were obtained from bone marrow samples of six individuals undergoing total hip replacement, and a large-scale transcriptome analysis, using Affymetrix HG-U133A Plus 2.0 array (Affymetrix((R)), Santa Clara, CA), was performed at the occurrence of specific events, including the appearance of MSC surface markers, formation of colonies, and deposition of mineral nodules. We focused our attention on 213 differentially upregulated genes, some belonging to well-known pathways and some having one or more Gene Ontology annotations related to bone cell biology, including angiogenesis, bone-related genes, cell communication, development and morphogenesis, transforming growth factor-beta signaling, and Wnt signaling. Twenty-nine genes, whose role in bone cell pathophysiology has not been described yet, were found. In conclusion, gene expression patterns that characterize the early, intermediate, and late phases of the osteogenic differentiation process of ex vivo-expanded MSCs were defined. These signatures represent a useful tool to monitor the osteogenic process, and to analyze a broad spectrum of functions of MSCs cultured on scaffolds, especially when the constructs are conceived for releasing growth factors or other signals to promote bone regeneration.


Assuntos
Osso e Ossos/citologia , Diferenciação Celular/genética , Perfilação da Expressão Gênica , Células-Tronco Hematopoéticas/citologia , Células-Tronco Mesenquimais/citologia , Humanos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
16.
Histochem Cell Biol ; 132(5): 547-57, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19711092

RESUMO

The nonadherent (NA) population of bone-marrow-derived mononuclear cells (MNC) has been demonstrated to be a source of osteogenic precursors in addition to the plastic-adherent mesenchymal stromal cells (MSC). In the current study, two subpopulations of late adherent (LA) osteoprogenitors were obtained by subsequent replating of NA cells, and their phenotypic, functional, and molecular properties were compared with those of early adherent (EA) MSC. Approximately 35% of MNC were LA cells, and they acquired a homogeneous expression of MSC antigens later than EA cells. In EA-MSC, the alkaline phosphatase (ALP) activity increased significantly from time of seeding to the first confluence, whereas in LA cells it raised later, after the addition of mineralization medium. All subpopulations were able to produce type I collagen and to deposit extracellular matrix with organized collagen fibrils. The proportion of large colonies with more than 50% of ALP positive cells as well as the calcium content was higher in LA than in EA cells. Molecular analysis highlighted the upregulation of bone-related genes in LA-MSC, especially after the addition of mineralization medium. Our results confirm that bone marrow contains LA osteoprogenitors which exhibit a delay in the differentiation process, despite an osteogenic potential similar to or better than EA-MSC. LA cells represent a reservoir of osteoprogenitors to be recruited to gain an adequate bone tissue repair and regeneration when a depletion of the most differentiated component occurs. Bone tissue engineering and cell therapy strategies could take advantage of LA cells, since an adequate amount of osteogenic MSCs may be obtained while avoiding bone marrow manipulation and cell culture expansion.


Assuntos
Células da Medula Óssea/citologia , Osteogênese/fisiologia , Células Estromais/citologia , Células Estromais/fisiologia , Adesão Celular/fisiologia , Células Cultivadas , Humanos , Imuno-Histoquímica , Fenótipo
17.
Chir Organi Mov ; 92(3): 161-8, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19043663

RESUMO

The role of growth factors (GF) in bone repair is widely recognised, particularly for bone morphogenetic proteins (BMPs), fibroblast growth factor (FGF), insulin-like growth factors (IGFs), platelet-derived growth factor (PDGF), transforming growth factor-beta (TGF-beta) and vascular endothelial growth factor (VEGF). GF are usually stored in the extracellular matrix (ECM), but after injury are actively released by ECM, cells and platelets. In this paper, the use of different recombinant GF for bone repair stimulation is summarised in experimental research and clinical applications. Drug delivery systems, including carriers, cell or gene therapy, are needed to ensure a sustained local release of the factors, but efficacy and potential side effects of such systems require additional research prior to clinical applications. Current sources for delivery of a GF mixture into the site of bone repair are platelet gel and demineralised bone matrix. Nevertheless, the levels of GF in such preparations are affected by variability among donors and differences in preparation. Autogenous GF, produced by the patient himself during the bone repair process, potentially interfere with prosthetic devices or even have a role in implant loosening due to the periprosthetic tissue reaction. In conclusion, GF are key components of functional bone regeneration: screening of basic research results and controlled clinical trials are accelerating the development of GF in orthopaedic surgery.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Osteogênese/efeitos dos fármacos , Animais , Doenças Ósseas/tratamento farmacológico , Matriz Óssea/efeitos dos fármacos , Proteínas Morfogenéticas Ósseas/farmacologia , Medicina Baseada em Evidências , Fatores de Crescimento de Fibroblastos/farmacologia , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/uso terapêutico , Fator de Crescimento Derivado de Plaquetas/farmacologia , Somatomedinas/farmacologia , Fator de Crescimento Transformador beta/farmacologia , Fator A de Crescimento do Endotélio Vascular/farmacologia
18.
Chir Organi Mov ; 92(2): 97-103, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18791684

RESUMO

Marrow stromal cells (MSC) are increasingly being introduced in orthopaedic practice as potentially powerful effectors of bone regeneration. Since cell recovery of MSC is affected by a high degree of individual variability, sources for collecting adequate amounts of safe and effective MSC under routine conditions are needed. We analysed if femoral bone marrow, which is usually discarded during total hip arthroplasty procedures, is a reliable source of MSC to enhance bone healing and regeneration. Mononuclear cells were isolated, assayed for typical MSC markers, harvested under appropriate culture conditions and evaluated for their ability to differentiate into osteoblasts. Cell recovery and osteogenic potential were independent from donor gender or age, suggesting that elderly individuals are eligible for autologous cell therapy. Although heterogeneous, the pool of MSC recovered from femoral marrow without further in vitro selection or manipulation proved highly effective in proliferating and differentiating along the osteogenic lineage. In conclusion, this source of MSC offers a valuable tool to be used to promote osteogenesis and implant fixation.


Assuntos
Células da Medula Óssea/citologia , Fêmur/citologia , Osteogênese , Células Estromais/citologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Artroplastia de Quadril , Biomarcadores , Regeneração Óssea/fisiologia , Adesão Celular , Diferenciação Celular , Linhagem da Célula , Separação Celular , Células Cultivadas/química , Células Cultivadas/citologia , Feminino , Luxação Congênita de Quadril/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite do Quadril/cirurgia , Osteoblastos/citologia , Fatores Sexuais , Engenharia Tecidual , Adulto Jovem
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