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1.
Methods Mol Biol ; 2777: 35-49, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38478334

RESUMO

Over the past 20 years, there has been a lot of interest in the study and investigation of cancer stem cells (CSCs) or tumor-initiating cells (TICs). CSCs are rare, dormant cells and able to self-renew and maintain tumor development and heterogeneity. A new age of basic and clinical cancer research, reclassification of human tumors, and the development of novel therapeutic approaches will undoubtedly result from a better knowledge of CSCs. In order to develop effective and therapeutic strategies to treat cancer, it is crucial to understand the basic characteristics of CSCs, their importance to cancer therapy, and methodologies to isolate, detect, and characterize them. Here, we outline the main methods and protocols to identify, isolate, and culture CSCs from primary tumors.


Assuntos
Neoplasias , Humanos , Neoplasias/patologia , Células-Tronco Neoplásicas/patologia
2.
Methods Mol Biol ; 2777: 83-89, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38478337

RESUMO

Cancer stem cells (CSCs) are a small tumor cell subpopulation, driving cancer initiation, progression, multidrug resistance, and metastasis. Several methods are used to detect and isolate CSCs by flow cytometry. Among these, measurement of aldehyde dehydrogenase (ALDH) activity within the cell is an assay widely used to identify and isolate CSCs from different types of solid tumors. The aldehyde dehydrogenase (ALDH) is a polymorphic enzyme responsible for the oxidation of aldehydes to carboxylic acids, overexpressed both in normal and cancer stem cells. In this chapter, it is described how CSCs are detected and isolated by using ALDH activity assay.


Assuntos
Neoplasias , Células-Tronco Neoplásicas , Linhagem Celular Tumoral , Células-Tronco Neoplásicas/metabolismo , Aldeído Desidrogenase/metabolismo , Citometria de Fluxo , Neoplasias/patologia
3.
Curr Opin Pharmacol ; 69: 102348, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36842387

RESUMO

Gastro-esophageal tumors constitute a big health problem. Treatment options still mainly rely on chemotherapy, and apart from human epidermal growth factor receptor 2 positive and microsatellite instable/Epstein-Barr Virus disease, there are no molecularly guided options. Therefore, despite the large number of identified molecular alterations, precision medicine is still far from the clinic. In this context, the recently developed technology of patient-derived organoids (PDOs) could offer the chance to accelerate drug development and biomarker discovery. Indeed, PDOs are 3D primary cultures that were shown to reproduce patient's tumor characteristics. Moreover, several reports indicated that PDOs can replicate patient's response to a given drug; therefore, they are one of the most promising tools for functional precision medicine.


Assuntos
Infecções por Vírus Epstein-Barr , Neoplasias Esofágicas , Humanos , Medicina de Precisão , Infecções por Vírus Epstein-Barr/metabolismo , Infecções por Vírus Epstein-Barr/patologia , Herpesvirus Humano 4 , Neoplasias Esofágicas/patologia , Organoides/metabolismo
4.
Cells ; 11(23)2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36497199

RESUMO

Type 1 diabetes (T1D) is an autoimmune disease with immune cells' islet infiltration (called "insulitis"), which leads to beta cell loss. Despite being the critical element of T1D occurrence and pathogenesis, insulitis is often present in a limited percentage of islets, also at diagnosis. Therefore, it is needed to define reproducible methods to detect insulitis and beta-cell decline, to allow accurate and early diagnosis and to monitor therapy. However, this goal is still far due to the morphological aspect of islet microvasculature, which is rather dense and rich, and is considerably rearranged during insulitis. More studies on microvasculature are required to understand if contrast-enhanced ultrasound sonography measurements of pancreatic blood-flow dynamics may provide a clinically deployable predictive marker to predict disease progression and therapeutic reversal in pre-symptomatic T1D patients. Therefore, it is needed to clarify the relation between insulitis and the dynamics of ß cell loss and with coexisting mechanisms of dysfunction, according to clinical stage, as well as the micro vessels' dynamics and microvasculature reorganization. Moreover, the ideal cell-based therapy of T1D should start from an early diagnosis allowing a sufficient isolation of specific Procr+ progenitors, followed by the generation and expansion of islet organoids, which could be transplanted coupled to an immune-regulatory therapy which will permit the maintenance of pancreatic islets and an effective and long-lasting insulitis reversal.


Assuntos
Diabetes Mellitus Tipo 1 , Células Secretoras de Insulina , Ilhotas Pancreáticas , Pancreatopatias , Humanos , Diabetes Mellitus Tipo 1/metabolismo , Pâncreas/patologia , Ilhotas Pancreáticas/metabolismo , Células Secretoras de Insulina/metabolismo , Células-Tronco/metabolismo
6.
Cells ; 10(11)2021 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-34831122

RESUMO

BACKGROUND: Hyaluronans exist in different forms, accordingly with molecular weight and degree of crosslinking. Here, we tested the capability to induce osteogenic differentiation in hDPSCs (human dental pulp stem cells) of three hyaluronans forms: linear pharmaceutical-grade hyaluronans at high and (HHA) low molecular weight (LHA) and hybrid cooperative complexes (HCC), containing both sizes. METHODS: hDPSCs were treated with HHA, LHA, HCC for 7, 14 and 21 days. The effects of hyaluronans on osteogenic differentiation were evaluated by qRT-PCR and WB of osteogenic markers and by Alizarin Red S staining. To identify the involved pathway, CD44 was analyzed by immunofluorescence, and YAP/TAZ expression was measured by qRT-PCR. Moreover, YAP/TAZ inhibitor-1 was used, and the loss of function of YAP/TAZ was evaluated by qRT-PCR, WB and immunofluorescence. RESULTS: We showed that all hyaluronans improves osteogenesis. Among these, HCC is the main inducer of osteogenesis, along with overexpression of bone related markers and upregulating CD44. We also found that this biological process is subordinate to the activation of YAP/TAZ pathway. CONCLUSIONS: We found that HA's molecular weight can have a relevant impact on HA performance for bone regeneration, and we unveil a new molecular mechanism by which HA acts on stem cells.


Assuntos
Osso e Ossos/citologia , Diferenciação Celular , Polpa Dentária/citologia , Ácido Hialurônico/farmacologia , Transdução de Sinais , Células-Tronco/citologia , Proteínas com Motivo de Ligação a PDZ com Coativador Transcricional/metabolismo , Proteínas de Sinalização YAP/metabolismo , Biomarcadores/metabolismo , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Separação Celular , Células Cultivadas , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Receptores de Hialuronatos/metabolismo , Sialoproteína de Ligação à Integrina/genética , Sialoproteína de Ligação à Integrina/metabolismo , Osteocalcina/genética , Osteocalcina/metabolismo , Osteogênese/efeitos dos fármacos , Osteogênese/genética , Osteopontina/genética , Osteopontina/metabolismo , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo
7.
Regen Biomater ; 8(3): rbaa052, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34211725

RESUMO

Gelatin hydrogels by microbial-transglutaminase crosslinking are being increasingly exploited for tissue engineering, and proved high potential in bone regeneration. This study aimed to evaluate, for the first time, the combination of enzymatically crosslinked gelatin with hyaluronan and the newly developed biotechnological chondroitin in enhancing osteogenic potential. Gelatin enzymatic crosslinking was carried out in the presence of hyaluronan or of a hyaluronan-chondroitin mixture, obtaining semi-interpenetrating gels. The latter proved lower swelling extent and improved stiffness compared to the gelatin matrix alone, whilst maintaining high stability. The heteropolysaccharides were retained for 30 days in the hydrogels, thus influencing cell response over this period. To evaluate the effect of hydrogel composition on bone regeneration, materials were seeded with human dental pulp stem cells and osteogenic differentiation was assessed. The expression of osteocalcin (OC) and osteopontin (OPN), both at gene and protein level, was evaluated at 7, 15 and 30 days of culture. Scanning electron microscopy (SEM) and two-photon microscope observations were performed to assess bone-like extracellular matrix (ECM) deposition and to observe the cell penetration depth. In the presence of the heteropolysaccharides, OC and OPN expression was upregulated and a higher degree of calcified matrix formation was observed. Combination with hyaluronan and chondroitin improved both the biophysical properties and the biological response of enzymatically crosslinked gelatin, fastening bone deposition.

8.
Materials (Basel) ; 14(13)2021 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-34279306

RESUMO

In oral implantology, the success and persistence of dental implants over time are guaranteed by the bone formation around the implant fixture and by the integrity of the peri-implant mucosa seal, which adheres to the abutment and becomes a barrier that hinders bacterial penetration and colonization close to the outer parts of the implant. Research is constantly engaged in looking for substances to coat the titanium surface that guarantees the formation and persistence of the peri-implant bone, as well as the integrity of the mucous perimeter surrounding the implant crown. The present study aimed to evaluate in vitro the effects of a titanium surface coated with polylysine homopolymers on the cell growth of dental pulp stem cells and keratinocytes to establish the potential clinical application. The results reported an increase in cell growth for both cellular types cultured with polylysine-coated titanium compared to cultures without titanium and those without coating. These preliminary data suggest the usefulness of polylysine coating not only for enhancing osteoinduction but also to speed the post-surgery mucosal healings, guarantee appropriate peri-implant epithelial seals, and protect the fixture against bacterial penetration, which is responsible for compromising the implant survival.

9.
Biomed Res Int ; 2021: 3582342, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33834063

RESUMO

In the field of biology and medicine, one hears often about stem cells and their potential. The dental implant new surfaces, subjected to specific treatments, perform better and allow for quicker healing times and better clinical performance. The purpose of this study is to evaluate from a biological point of view the interaction and cytotoxicity between stem cells derived from dental pulp (DPSCs) and titanium surfaces. Through the creation of complex cells/implant, this study is aimed at analyzing the cytotoxicity of dental implant surfaces (Myth (Maipek Manufacturer Industrial Care, Naples, Italy)) and the adhesion capacity of cells on them and at considering the essential factors for implant healing such as osteoinduction and vasculogenesis. These parameters are pointed out through histology (3D cell culture), immunofluorescence, proliferation assays, scanning electron microscopy, and PCR investigations. The results of the dental implant surface and its interaction with the DPSCs are encouraging, obtaining results increasing the mineralization of the tissues. The knowledge of this type of interaction, highlighting its chemical and biological features, is certainly also an excellent starting point for the development of even more performing surfaces for having better healing in the oral surgical procedures related to dental implant positioning.


Assuntos
Implantes Dentários , Polpa Dentária/citologia , Células-Tronco/citologia , Matriz Óssea/efeitos dos fármacos , Matriz Óssea/metabolismo , Adesão Celular/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Meios de Cultivo Condicionados/farmacologia , Humanos , Neovascularização Fisiológica/efeitos dos fármacos , Osseointegração/efeitos dos fármacos , Osteocalcina/metabolismo , Células-Tronco/efeitos dos fármacos , Células-Tronco/ultraestrutura , Propriedades de Superfície , Fator A de Crescimento do Endotélio Vascular/metabolismo
10.
Cell Death Dis ; 11(10): 850, 2020 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-33051434

RESUMO

The ß2-Adrenergic receptor (ß2-AR) is a G protein-coupled receptor (GPCR), involved in the development of many cancers, among which HNSCC. In this contest, ß2-AR signaling interacts with different pathways, such as PI3K and MAPK, commonly activated by TK receptors. For this reason, TK blockade is one of the most adopted therapeutic strategies in HNSCC patients. In our study we investigated the effects of the ß2-AR blocking in HNSCC cell lines, using the selective inhibitor ICI118,551 (ICI), in combination with the MAPK inhibitor U0126. We found that ICI leads to the blocking of p38 and NF-kB oncogenic pathways, strongly affecting also the ERK and PI3K pathways. Cotreatment with U0126 displays a synergic effect on cell viability and pathway alteration. Interestingly, we found that the ß2-AR blockade affects Nrf2-Keap1 stability and its nuclear translocation leading to a drastic ROS increase and oxidative stress. Our results are confirmed by a TCGA dataset analysis, showing that NFE2L2 gene is commonly overexpressed in HNSC, and correlated with a lower survival rate. In our system, the PI3K pathway inhibition culminated in the blocking of pro-survival autophagy, a mechanism normally adopted by cancer cells to became less responsive to the therapies. The mTOR expression, commonly upregulated in HNSC, was reduced in patients with disease-recurrence. It is well known that mTOR has a strong autophagy inhibition effect, therefore its downregulation promoted pro-survival autophagy, with a related increase recurrence rate. Our findings highlight for the first time the key role of ß2-AR and related pathway in HNSCC cell proliferation and drug resistance, proposing it as a valuable therapeutic molecular target.


Assuntos
Antagonistas de Receptores Adrenérgicos beta 2/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Fator 2 Relacionado a NF-E2/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Receptores Adrenérgicos beta 2/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Antagonistas de Receptores Adrenérgicos beta 2/administração & dosagem , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sinergismo Farmacológico , Neoplasias de Cabeça e Pescoço/metabolismo , Neoplasias de Cabeça e Pescoço/patologia , Humanos , MAP Quinase Quinase 1/antagonistas & inibidores , MAP Quinase Quinase 2/antagonistas & inibidores , Propanolaminas/administração & dosagem , Propanolaminas/farmacologia , Inibidores de Proteínas Quinases/administração & dosagem , Transdução de Sinais , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia
11.
Cancer Treat Rev ; 88: 102043, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32505806

RESUMO

Autophagy is a self-degradative cellular process, involved in stress response such as starvation, hypoxia, and oxidative stress. This mechanism balances macro-molecule recycling to regulate cell homeostasis. In cancer, autophagy play a role in the development and progression, while several studies describe it as one of the key processes in drug resistance. In the last years, in addition to standard anti-cancer treatments such as chemotherapies and irradiation, targeted therapy became one of the most adopted strategies in clinical practices, mainly due to high specificity and reduced side effects. However, similar to standard treatments, drug resistance is the main challenge in most patients. Here, we summarize recent studies that investigated the role of autophagy in drug resistance after targeted therapy in different types of cancers. We highlight positive results and limitations of pre-clinical and clinical studies in which autophagy inhibitors are used in combination with targeted therapies.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Animais , Anticorpos Monoclonais/farmacologia , Antineoplásicos Imunológicos/farmacologia , Autofagia/efeitos dos fármacos , Autofagia/fisiologia , Humanos , Imunotoxinas/farmacologia , Terapia de Alvo Molecular , Neoplasias/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Bibliotecas de Moléculas Pequenas/farmacologia
12.
J Exp Clin Cancer Res ; 38(1): 160, 2019 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-30987650

RESUMO

BACKGROUND: Glucose-6-phospate dehydrogenase (G6PD) is the limiting enzyme of the pentose phosphate pathway (PPP) correlated to cancer progression and drug resistance. We previously showed that G6PD inhibition leads to Endoplasmic Reticulum (ER) stress often associated to autophagy deregulation. The latter can be induced by target-based agents such as Lapatinib, an anti-HER2 tyrosine kinase inhibitor (TKI) largely used in breast cancer treatment. METHODS: Here we investigate whether G6PD inhibition causes autophagy alteration, which can potentiate Lapatinib effect on cancer cells. Immunofluorescence and flow cytometry for LC3B and lysosomes tracker were used to study autophagy in cells treated with lapatinib and/or G6PD inhibitors (polydatin). Immunoblots for LC3B and p62 were performed to confirm autophagy flux analyses together with puncta and colocalization studies. We generated a cell line overexpressing G6PD and performed synergism studies on cell growth inhibition induced by Lapatinib and Polydatin using the median effect by Chou-Talay. Synergism studies were additionally validated with apoptosis analysis by annexin V/PI staining in the presence or absence of autophagy blockers. RESULTS: We found that the inhibition of G6PD induced endoplasmic reticulum stress, which was responsible for the deregulation of autophagy flux. Indeed, G6PD blockade caused a consistent increase of autophagosomes formation independently from mTOR status. Cells engineered to overexpress G6PD became resilient to autophagy and resistant to lapatinib. On the other hand, G6PD inhibition synergistically increased lapatinib-induced cytotoxic effect on cancer cells, while autophagy blockade abolished this effect. Finally, in silico studies showed a significant correlation between G6PD expression and tumour relapse/resistance in patients. CONCLUSIONS: These results point out that autophagy and PPP are crucial players in TKI resistance, and highlight a peculiar vulnerability of breast cancer cells, where impairment of metabolic pathways and autophagy could be used to reinforce TKI efficacy in cancer treatment.


Assuntos
Antineoplásicos/farmacologia , Autofagia/efeitos dos fármacos , Neoplasias da Mama/metabolismo , Glucosefosfato Desidrogenase/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Apoptose/efeitos dos fármacos , Autofagia/genética , Neoplasias da Mama/genética , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Sinergismo Farmacológico , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Estresse do Retículo Endoplasmático/genética , Feminino , Expressão Gênica , Glucosefosfato Desidrogenase/genética , Glucosefosfato Desidrogenase/metabolismo , Humanos , Lapatinib/farmacologia , Prognóstico , Recidiva
13.
Cells ; 8(3)2019 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-30841579

RESUMO

Epigenetic regulation has been considered an important mechanism for influencing stem cell differentiation. In particular, histone deacetylases (HDACs) have been shown to play a role in the osteoblast differentiation of mesenchymal stem cells (MSCs). In this study, the effect of the HDAC inhibitor, valproic acid (VPA), on bone formation in vivo by MSCs was determined. Surprisingly, VPA treatment, unlike other HDAC inhibitors, produced a well-organized lamellar bone tissue when MSCs⁻collagen sponge constructs were implanted subcutaneously into nonobese diabetic/severe combined immunodeficiency (NOD/SCID) mice, although a decrease of osteocalcin (OC) expression was observed. Consequently, we decided to investigate the molecular mechanisms by which VPA exerts such effects on MSCs. We identified the glucocorticoid receptor (GR) as being responsible for that downregulation, and suggested a correlation between GR and HDAC2 inhibition after VPA treatment, as evidenced by HDAC2 knockdown. Furthermore, using co-immunoprecipitation analysis, we showed for the first time in the cytoplasm, binding between GR and HDAC2. Additionally, chromatin immunoprecipitation (ChIP) assays confirmed the role of GR in OC downregulation, showing recruitment of GR to the nGRE element in the OC promoter. In conclusion, our results highlight the existence of a cross-talk between GR and HDAC2, providing a mechanistic explanation for the influence of the HDAC inhibitor (namely VPA) on osteogenic differentiation in MSCs. Our findings open new directions in targeted therapies, and offer new insights into the regulation of MSC fate determination.


Assuntos
Citoplasma/metabolismo , Histona Desacetilase 2/metabolismo , Células-Tronco Mesenquimais/metabolismo , Osteocalcina/metabolismo , Receptores de Glucocorticoides/metabolismo , Ácido Valproico/farmacologia , Adulto , Biomarcadores/metabolismo , Citoplasma/efeitos dos fármacos , Polpa Dentária/citologia , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Inibidores de Histona Desacetilases/farmacologia , Humanos , Masculino , Células-Tronco Mesenquimais/efeitos dos fármacos , Mifepristona/farmacologia , Osteocalcina/genética , Osteogênese/efeitos dos fármacos , Osteogênese/genética , Implantação de Prótese , Ligação Proteica/efeitos dos fármacos , Elementos de Resposta/genética , Adulto Jovem
14.
J Exp Clin Cancer Res ; 37(1): 296, 2018 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-30509303

RESUMO

BACKGROUND: Cancer stem cells (CSCs) play a key role in cancer initiation, progression and chemoresistance. Epigenetic alterations have been identified as prominent factors that contribute to the CSCs phenotype. Here, we investigated the effects of the HDAC inhibitor valproic acid (VPA) and the demethylating agent, 5'azacytidine (DAC) on the stem phenotype of MG63 and Saos2 osteosarcoma cell lines. METHODS: Saos2 and MG63 cells were treated with DAC and VPA, alone and in combination. Untreated and treated cells were examined for stemness phenotype by cytometry and real-time PCR. Sarcospheres and colonies formation were also evaluated. Moreover, histone modification and methylation were tested by flow cytomery and western blotting. HDAC2 depleted cells were examined for stemness phenotype and their ability to generate tumors in NOD/SCID IL2R-gamma-0 (NSG) mice. HDAC2 expression on human osteosarcoma tissues was evaluated. RESULTS: We found that DAC and VPA induce an increased expression of stem markers including CD133, OCT4, SOX2 and NANOG, and an increased ability in sarcospheres and colonies formation efficiency. Interestingly, we showed that DAC and VPA treatment decreased repressive histone markers, while increased the active ones. These histone modifications were also associated with an increase of acetylation of histones H3, a decrease of DNA global methylation, HDAC2 and DNMT3a. Furthermore, HDAC2 silenced-MG63 and Saos2 cells acquired a stem phenotype, and promoted in vivo tumorigenesis. In human osteosarcoma tissues, HDAC2 was strongly expressed in nucleus. CONCLUSIONS: Collectively, our results suggest that VPA and DAC induce an expansion of osteosarcoma CSCs, and we report for the first time that HDAC2 is a key factor regulating both CSCs phenotype and in vivo cancer growth. In conclusion, we have identified HDAC2 as a potential therapeutic target in human osteosarcoma treatment.


Assuntos
Neoplasias Ósseas/enzimologia , Histona Desacetilase 2/deficiência , Células-Tronco Neoplásicas/enzimologia , Osteossarcoma/enzimologia , Animais , Azacitidina/farmacologia , Neoplasias Ósseas/genética , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Metilação de DNA , Xenoenxertos , Histona Desacetilase 2/antagonistas & inibidores , Histona Desacetilase 2/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/patologia , Osteossarcoma/genética , Osteossarcoma/patologia , Transfecção , Ácido Valproico/farmacologia
15.
Front Physiol ; 9: 547, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29892229

RESUMO

Human dental pulp is considered an interesting source of adult stem cells, due to the low-invasive isolation procedures, high content of stem cells and its peculiar embryological origin from neural crest. Based on our previous findings, a dental pulp stem cells sub-population, enriched for the expression of STRO-1, c-Kit, and CD34, showed a higher neural commitment. However, their biological properties were compromised when cells were cultured in adherent standard conditions. The aim of this study was to evaluate the ability of three dimensional floating spheres to preserve embryological and biological properties of this sub-population. In addition, the expression of the inwardly rectifying potassium channel Kir4.1, Fas and FasL was investigated in 3D-sphere derived hDPSCs. Our data showed that 3D sphere-derived hDPSCs maintained their fibroblast-like morphology, preserved stemness markers expression and proliferative capability. The expression of neural crest markers and Kir4.1 was observed in undifferentiated hDPSCs, furthermore this culture system also preserved hDPSCs differentiation potential. The expression of Fas and FasL was observed in undifferentiated hDPSCs derived from sphere culture and, noteworthy, FasL was maintained even after the neurogenic commitment was reached, with a significantly higher expression compared to osteogenic and myogenic commitments. These data demonstrate that 3D sphere culture provides a favorable micro-environment for neural crest-derived hDPSCs to preserve their biological properties.

16.
Cell Death Dis ; 9(5): 572, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29760380

RESUMO

Pentose phosphate pathway (PPP) is a major glucose metabolism pathway, which has a fundamental role in cancer growth and metastasis. Even though PPP blockade has been pointed out as a very promising strategy against cancer, effective anti-PPP agents are not still available in the clinical setting. Here we demonstrate that the natural molecule polydatin inhibits glucose-6-phosphate dehydrogenase (G6PD), the key enzyme of PPP. Polydatin blocks G6PD causing accumulation of reactive oxygen species and strong increase of endoplasmic reticulum stress. These effects are followed by cell cycle block in S phase, an about 50% of apoptosis, and 60% inhibition of invasion in vitro. Accordingly, in an orthotopic metastatic model of tongue cancer, 100 mg/kg polydatin induced an about 30% tumor size reduction with an about 80% inhibition of lymph node metastases and 50% reduction of lymph node size (p < 0.005). Polydatin is not toxic in animals up to a dose of 200 mg/kg and a phase II clinical trial shows that it is also well tolerated in humans (40 mg twice a day for 90 days). Thus, polydatin may be used as a reliable tool to limit human cancer growth and metastatic spread.


Assuntos
Glucosefosfato Desidrogenase/antagonistas & inibidores , Glucosídeos/farmacologia , Proteínas de Neoplasias/antagonistas & inibidores , Neoplasias/enzimologia , Via de Pentose Fosfato/efeitos dos fármacos , Pontos de Checagem da Fase S do Ciclo Celular/efeitos dos fármacos , Estilbenos/farmacologia , Animais , Glucosefosfato Desidrogenase/genética , Glucosefosfato Desidrogenase/metabolismo , Humanos , Células MCF-7 , Masculino , Camundongos Nus , Metástase Neoplásica , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias/patologia , Pontos de Checagem da Fase S do Ciclo Celular/genética , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Cell Physiol Biochem ; 44(3): 1078-1092, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29179206

RESUMO

BACKGROUND/AIMS: Adipose-derived Stem Cells (ASCs) are used in Regenerative Medicine, including fat grafting, recovery from local tissue ischemia and scar remodeling. The aim of this study was to evaluate hyaluronan based gel effects on ASCs differentiation and proliferation. METHODS: Comparative analyses using high (H) and low (L) molecular weight hyaluronans (HA), hyaluronan hybrid cooperative complexes (HCCs), and high and medium cross-linked hyaluronan based dermal fillers were performed. Human ASCs were characterized by flow cytometry using CD90, CD34, CD105, CD29, CD31, CD45 and CD14 markers. Then, cells were treated for 7, 14 and 21 days with hyaluronans. Adipogenic differentiation was evaluated using Oil red-O staining and expression of leptin, PPAR-γ, LPL and adiponectin using qRT-PCR. Adiponectin was analyzed by immunofluorescence, PPAR-γ and adiponectin were analyzed using western blotting. ELISA assays for adiponectin and leptin were performed. RESULTS: HCCs highly affected ASCs differentiation by up-regulating adipogenic genes and related proteins, that were also secreted in the culture medium. H-HA and L-HA induced a lower level of ASCs differentiation. CONCLUSION: HCCs-based formulations clearly enhance adipogenic differentiation and proliferation, when compared with linear HA and cross-linked hyaluronans. Injection of HCCs in subdermal fat compartment may recruit and differentiate stem cells in adipocytes, and considerably improving fat tissue renewal.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Ácido Hialurônico/farmacologia , Adipogenia/efeitos dos fármacos , Adiponectina/análise , Adiponectina/metabolismo , Tecido Adiposo/citologia , Adulto , Antígenos CD/metabolismo , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Ácido Hialurônico/química , Leptina/análise , Leptina/metabolismo , Lipase Lipoproteica/metabolismo , Microscopia de Fluorescência , Pessoa de Meia-Idade , Peso Molecular , PPAR gama/metabolismo , Fenótipo , Células-Tronco/citologia , Células-Tronco/metabolismo , Cirurgia Plástica
18.
Clin Sci (Lond) ; 131(8): 699-713, 2017 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-28209631

RESUMO

Human dental pulp stem cells (hDPSCs) are mesenchymal stem cells that have been successfully used in human bone tissue engineering. To establish whether these cells can lead to a bone tissue ready to be grafted, we checked DPSCs for their osteogenic and angiogenic differentiation capabilities with the specific aim of obtaining a new tool for bone transplantation. Therefore, hDPSCs were specifically selected from the stromal-vascular dental pulp fraction, using appropriate markers, and cultured. Growth curves, expression of bone-related markers, calcification and angiogenesis as well as an in vivo transplantation assay were performed. We found that hDPSCs proliferate, differentiate into osteoblasts and express high levels of angiogenic genes, such as vascular endothelial growth factor and platelet-derived growth factor A. Human DPSCs, after 40 days of culture, give rise to a 3D structure resembling a woven fibrous bone. These woven bone (WB) samples were analysed using classic histology and synchrotron-based, X-ray phase-contrast microtomography and holotomography. WB showed histological and attractive physical qualities of bone with few areas of mineralization and neovessels. Such WB, when transplanted into rats, was remodelled into vascularized bone tissue. Taken together, our data lead to the assumption that WB samples, fabricated by DPSCs, constitute a noteworthy tool and do not need the use of scaffolds, and therefore they are ready for customized regeneration.


Assuntos
Substitutos Ósseos , Polpa Dentária/citologia , Células-Tronco/citologia , Engenharia Tecidual/métodos , Adulto , Animais , Transplante Ósseo/métodos , Calcificação Fisiológica/fisiologia , Diferenciação Celular/fisiologia , Proliferação de Células , Separação Celular/métodos , Células Cultivadas , Quimiotaxia , Humanos , Camundongos Nus , Neovascularização Fisiológica/fisiologia , Osteocalcina/metabolismo , Osteogênese/fisiologia , Microtomografia por Raio-X/métodos , Adulto Jovem
19.
Cell Death Dis ; 8(1): e2568, 2017 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-28102844

RESUMO

Recent studies showed that mesenchymal stem cells derived from adipose tissue can promote tumour progression, raising some concerns regarding their use in regenerative medicine. In this context, we co-cultured either SAOS2 osteosarcoma or MCF7 breast cancer cells with human adipose stem cells (hASCs), in order to evaluate potential effects of cancer cells on hASCs differentiation, in vitro and in vivo. In this study we observed that both SAOS2 and MCF7 cell lines induced an increase in hASCs proliferation, compared to hASCs alone, but, surprisingly, neither changes in the expression of CD90, CD29, CD324 and vimentin, nor variations in the Twist and Slug mRNAs were detectable. Noteworthy, SAOS2 and MCF7 cells induced in hASCs an upregulation of CD34 expression and stemness genes, including OCT3/4, Nanog, Sox2 and leptin, and a decrease in angiogenic factors, including CD31, PDGFα, PDGFRα, PDGFRß and VEGF. SMAD and pSMAD2/3 increased only in hASCs alone. After 21 days of co-culture, hASCs differentiated both in adipocytes and endothelial cells. Moreover, co-injection of MCF7 cells with hASCs led to the formation of a highly vascularized tumour. Taken together our findings suggest that mesenchymal stem cells, under tumour cell induction, do not differentiate in vitro or facilitate the angiogenesis of the tumour in vivo, thus opening interesting new scenarios in the relationship between cancer and stem cells. These findings may also lead to greater caution, when managing autologous fat grafts in cancer patients.


Assuntos
Diferenciação Celular/genética , Proliferação de Células/genética , Células-Tronco Mesenquimais/citologia , Neovascularização Patológica/metabolismo , Adipócitos/citologia , Adipócitos/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Técnicas de Cocultura , Células Endoteliais/citologia , Citometria de Fluxo , Humanos , Células MCF-7 , Células-Tronco Mesenquimais/metabolismo , Camundongos , Neovascularização Patológica/genética , Neovascularização Patológica/patologia
20.
Front Physiol ; 7: 354, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27594842

RESUMO

Human dental pulp stem cells (hDPSCs), selected from the stromal-vascular fraction of dental pulp, are ecto-mesenchymal stem cells deriving from neural crests, successfully used in human bone tissue engineering. For their use in human therapy GMP procedures are required. For instance, the use of fetal bovine serum (FBS) is strongly discouraged in clinical practice due to its high risk of prions and other infections for human health. Alternatively, clinical grade sera have been suggested, including the New Zealand FBS (NZ-FBS). Therefore, the aim of this study was to evaluate the behavior of hDPSCs expanded in culture medium containing NZ-FBS. Since it was widely demonstrated hDPSCs display relevant capabilities to differentiate into osteogenic and angiogenic lineages, we performed a comparative study to assess if these features are also retained by cultivating the cells with a safer serum never tested on this cell line. hDPSCs were grown using NZ-FBS and conventional (C-FBS) for 7, 14, and 21 days, in both 2D and 3D cultures. Growth curves, expression of bone-related markers, calcification and angiogenesis were evaluated. NZ-FBS induced significant cell growth with respect to C-FBS and promoted an earlier increase expression of osteogenic markers, in particular of those involved in the formation of mineralized matrix (BSP and OPN) within 14 days. In addition, hDPSCs cultured in presence of NZ-FBS were found to produce higher mRNA levels of the angiogenic factors, such as VEGF and PDGFA. Taken together, our results highlight that hDPSCs proliferate, enhance their osteogenic commitment and increase angiogenic factors in NZ-FBS containing medium. These features have also been found when hDPSC were seeded on the clinical-grade collagen I scaffold (Bio-Gide®), leading to the conclusion that for human therapy some procedures and above all the use of GMP-approved materials have no negative impact.

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