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1.
Cancer Treat Rev ; 127: 102750, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38703592

RESUMO

Traditional chemotherapy-based adjuvant therapies for locally advanced pancreatic ductal adenocarcinoma (PDAC) have been associated with poor clinical outcomes driven partly by its complex anatomy and molecular heterogeneity. Treatment for PDAC is challenged by presence of a dense tumour microenvironment involving an interplay of multiple tumoural and stromal components which promote metastatic oncogenic behaviour. PDAC also involves aberrations in multiple signalling pathways with paucity of treatment options against the most common mutations including KRAS, TP53, CDKN2A andSMAD4. However, recent discovery of new mechanisms implicated in pancreatic carcinogenesis have led to identification of promising mechanistic therapeutic targets such as NET1 and ULK1. Early evidence also suggests the utility of targeting multiple DNA repair processes, modulators of DNA replication and major DNA damage response regulators. We explore the clinical rationale behind a neoadjuvant therapeutic strategy and emerging predictors of survival benefit associated with this approach. We also discuss challenges and opportunities originating from recent clinical trials evaluating neoadjuvant treatments composed of various combinations of radiotherapy, chemotherapy and immunotherapeutic regimens that have aimed to address some of these biological challenges. Selective treatment of patients harbouring specific genomic aberrations with targeted agents and immunotherapy can translate into optimum survival outcomes in PDAC. We also share perspectives on emerging prospective clinical evidence regarding stromal modifying agents, such as Tumour Growth Factor-Beta and Connective Tissue Growth Factor inhibitors along with novel vaccination-based approaches in improving PDAC outcomes.


Assuntos
Carcinoma Ductal Pancreático , Terapia Neoadjuvante , Neoplasias Pancreáticas , Humanos , Carcinoma Ductal Pancreático/terapia , Carcinoma Ductal Pancreático/patologia , Terapia Neoadjuvante/métodos , Neoplasias Pancreáticas/terapia , Neoplasias Pancreáticas/patologia , Microambiente Tumoral
2.
J Neuromuscul Dis ; 10(4): 685-699, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37248912

RESUMO

BACKGROUND: Duchenne muscular dystrophy (DMD) is a neuromuscular disease stemming from dystrophin gene mutations. Lack of dystrophin leads to progressive muscle damage and replacement of muscle with fibrotic and adipose tissue. Pamrevlumab (FG-3019), a fully human monoclonal antibody that binds to connective tissue growth factor (CTGF), is in Phase III development for treatment of DMD and other diseases. METHODS: MISSION (Study 079; NCT02606136) was an open-label, Phase II, single-arm trial of pamrevlumab in 21 non-ambulatory patients with DMD (aged≥12 years, receiving corticosteroids) who received 35-mg/kg intravenous infusions every 2 weeks for 2 years. The primary endpoint was change from baseline in percent predicted forced vital capacity (ppFVC). Secondary endpoints included other pulmonary function tests, upper limb function and strength assessments, and changes in upper arm fat and fibrosis scores on magnetic resonance imaging. RESULTS: Fifteen patients completed the trial. Annual change from baseline (SE) in ppFVC was -4.2 (0.7) (95% CI -5.5, -2.8). Rate of decline in ppFVC in pamrevlumab-treated patients was slower than observed in historical published trials of non-ambulatory patients. MISSION participants experienced slower-than-anticipated muscle function declines compared with natural history and historical published trials of non-ambulatory patients with DMD. Pamrevlumab was well-tolerated. Treatment-emergent adverse events were mild to moderate, and none led to study discontinuation. CONCLUSIONS: nti-CTGF therapy with pamrevlumab represents a potential treatment for DMD. The lack of internal control group limits the results.


Assuntos
Distrofia Muscular de Duchenne , Humanos , Distrofia Muscular de Duchenne/genética , Distrofina , Anticorpos Monoclonais/uso terapêutico , Fator de Crescimento do Tecido Conjuntivo
3.
Ther Adv Med Oncol ; 13: 17588359211059586, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34868352

RESUMO

The treatment paradigm for locally advanced pancreatic cancer (LAPC) is evolving rapidly. The development of neoadjuvant therapies composed of combination therapies and the evaluation of their impact on conversion to borderline resectable (BR) status, resection, and ultimately overall survival (OS) are presently being pursued. These efforts justify re-visiting study endpoints in order to better predict therapeutic effects on OS, by capturing not only the achievement of R0 resection at the end of induction therapy but also the long-term reductions in the rate of local and distal recurrence. The proposed herein event-free survival (EFS) endpoint, with its novel definition specific to LAPC, is formulated to achieve these objectives. It is an analog to disease-free survival (DFS) endpoint in the adjuvant setting applied to the neoadjuvant setting and may be a valuable surrogate endpoint for this patient population.

4.
ESMO Open ; 5(4)2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32817130

RESUMO

PURPOSE: Pancreatic ductal adenocarcinomas exhibit a high degree of desmoplasia due to extensive extracellular matrix deposition. Encasement of mesenteric vessels by stroma in locally advanced pancreatic cancer (LAPC) prevents surgical resection. This study sought to determine if the addition of a monoclonal antibody to connective tissue growth factor, pamrevlumab, to neoadjuvant chemotherapy would be safe and lead to improved resectability in this surgically adverse patient population. METHODS: In this phase I/II trial, 37 patients with LAPC were randomised 2:1 to gemcitabine/nab-paclitaxel plus (Arm A, n=24) or minus (Arm B, n=13) pamrevlumab. Those who completed six cycles of treatment were assessed for surgical eligibility by protocol-defined criteria. Resection rates, progression-free and overall survival were evaluated. RESULTS: Eighteen (75%) patients in Arm A and seven (54%) in Arm B completed six cycles of therapy with similar toxicity patterns. In Arms A and B, carbohydrate antigen 19-9 response, as defined by ≥50% decline from baseline, occurred in 13 (65%) and 5 (42%), respectively. Sixteen (16%) per cent of patients were radiographically downstaged by National Comprehensive Cancer Network criteria (5 in Arm A (21%) and 1 (8%) in Arm B). Positron emission tomography normalised in 9 (38%) vs 3 (23%) of patients in Arm A vs Arm B, respectively, and correlated with surgical exploration. Eligibility for surgical exploration was 17 (71%) vs 2 (15%) (p=0.0019) and resection was achieved in 8 (33%) vs 1 (8%) of patients in Arm A vs Arm B (p=0.1193), respectively. Postoperative complication rates were not different between arms. CONCLUSIONS: Neoadjuvant chemotherapy with pamrevlumab holds promise for enhancing resection rates in patients with LAPC without added toxicity. This combination merits evaluation in a larger patient cohort.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Pancreáticas , Adolescente , Adulto , Idoso , Albuminas , Desoxicitidina/análogos & derivados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Paclitaxel , Pâncreas , Tomografia Computadorizada por Raios X , Adulto Jovem , Gencitabina
5.
Cell Tissue Bank ; 14(2): 175-86, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22592563

RESUMO

Cryopreservation is a common procedure widely used in biological and clinical sciences. Similar protocols are also applied in preserving cancer stem cells, a field with high promises and challenges. Specific cell surface membrane proteins are considered to be biomarkers of cancer stem cells and they may play a critical role in differentiating stem cells from non stem cells. We have looked at the possible effect of long-term cryopreservation on the molecular integrity of breast MCF7 and lung, A549 and H460, cancer stem cells and to assess if these cells are more sensitive to long-term storage process. We analyzed the expression of CD24 and CD38 as two potent biomarkers of lung cancer stem cells and EpCAM and ALDH that are used as biomarkers of a wide range of cancer stem cells. We also selected three genes essential for the normal functioning of the cells, Fos, MUC1, and HLA. Our results indicate a pattern of down-regulation in the expression of the genes following freezing, in particular among cell surface marker proteins. Global gene expression of the post-thaw breast and lung cancer stem cells also reveals a significant down-regulation in freeze-thaw cells independent from each other. Analyzing the canonical pathways between two populations reveals a significant alteration in the gene expression of the pathways involved in cell cycle, mitosis, and ataxia telangiectasia mutated pathways. Overall, our results indicate that current protocols for long-term storage of lung and breast cancer stem cells may substantially influence the activity and function of genes.


Assuntos
Bancos de Espécimes Biológicos , Neoplasias da Mama/genética , Criopreservação/métodos , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/genética , Neoplasias Pulmonares/genética , Células-Tronco Neoplásicas/metabolismo , ADP-Ribosil Ciclase 1/genética , ADP-Ribosil Ciclase 1/metabolismo , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Antígeno CD24/genética , Antígeno CD24/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/fisiologia , Regulação para Baixo/genética , Feminino , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Mucina-1/genética , Mucina-1/metabolismo , Células-Tronco Neoplásicas/patologia , Fatores de Tempo , Receptor fas/genética , Receptor fas/metabolismo
6.
J Transl Med ; 9: 213, 2011 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-22168535

RESUMO

BORIS, or CTCFL, the so called Brother of the Regulator of Imprinted Sites because of the extensive homology in the central DNA binding region of the protein to the related regulator, CTCF, is expressed in early gametogenesis and in multiple cancers but not in differentiated somatic cells. Thus it is a member of the cancer testes antigen group (CTAs). Since BORIS and CTCF target common DNA binding sites, these proteins function on two levels, the first level is their regulation via the methylation context of the DNA target site and the second level is their distinct and different epigenetic associations due to differences in the non-homologous termini of the proteins. The regulation on both of these levels is extensive and complex and the sphere of influence of each of these proteins is associated with vastly different cellular signaling processes. On the level of gene expression, BORIS has three known promoters and multiple spliced mRNAs which adds another level of complexity to this intriguing regulator. BORIS expression is observed in the majority of cancer tissues and cell lines analyzed up to today. The expression profile and essential role of BORIS in cancer make this molecule very attractive target for cancer immunotherapy. This review summarizes what is known about BORIS regarding its expression, structure, and function and then presents some theoretical considerations with respect to its genome wide influence and its potential for use as a vaccine for cancer immunotherapy.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Epigênese Genética , Genoma Humano/genética , Fator de Ligação a CCCTC , Proteínas de Ligação a DNA/genética , Humanos , Neoplasias/genética , Neoplasias/imunologia , Neoplasias/terapia , Ligação Proteica , Proteínas Repressoras
7.
J Transl Med ; 9: 34, 2011 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-21450109

RESUMO

BACKGROUND: Many peptide-based cancer vaccines have been tested in clinical trials with a limited success, mostly due to difficulties associated with peptide stability and delivery, resulting in inefficient antigen presentation. Therefore, the development of suitable and efficient vaccine carrier systems remains a major challenge. METHODS: To address this issue, we have engineered polylactic-co-glycolic acid (PLGA) nanoparticles incorporating: (i) two MHC class I-restricted clinically-relevant peptides, (ii) a MHC class II-binding peptide, and (iii) a non-classical MHC class I-binding peptide. We formulated the nanoparticles utilizing a double emulsion-solvent evaporation technique and characterized their surface morphology, size, zeta potential and peptide content. We also loaded human and murine dendritic cells (DC) with the peptide-containing nanoparticles and determined their ability to present the encapsulated peptide antigens and to induce tumor-specific cytotoxic T lymphocytes (CTL) in vitro. RESULTS: We confirmed that the nanoparticles are not toxic to either mouse or human dendritic cells, and do not have any effect on the DC maturation. We also demonstrated a significantly enhanced presentation of the encapsulated peptides upon internalization of the nanoparticles by DC, and confirmed that the improved peptide presentation is actually associated with more efficient generation of peptide-specific CTL and T helper cell responses. CONCLUSION: Encapsulating antigens in PLGA nanoparticles offers unique advantages such as higher efficiency of antigen loading, prolonged presentation of the antigens, prevention of peptide degradation, specific targeting of antigens to antigen presenting cells, improved shelf life of the antigens, and easy scale up for pharmaceutical production. Therefore, these findings are highly significant to the development of synthetic vaccines, and the induction of CTL for adoptive immunotherapy.


Assuntos
Apresentação de Antígeno/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Imunoterapia/métodos , Nanopartículas/química , Neoplasias/terapia , Peptídeos/imunologia , Animais , Biodegradação Ambiental , Diferenciação Celular , Linhagem Celular Tumoral , Células Dendríticas/citologia , Células Dendríticas/metabolismo , Endocitose , Humanos , Proteínas Imobilizadas/imunologia , Ácido Láctico/metabolismo , Camundongos , Nanopartículas/ultraestrutura , Neoplasias/imunologia , Fenótipo , Ácido Poliglicólico/metabolismo , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Linfócitos T Citotóxicos/imunologia
8.
Curr Top Med Chem ; 11(13): 1599-605, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21446910

RESUMO

Due to the recent advancements in stem cell biology and engineering, scientists have been increasingly interested in creating in vitro niches for embryonic and adult stem cells, and, following induction and differentiation with the appropriate media, the production of large scale blood production. This artificially created niche for hematopoietic cells will be composed of three materials: the stem cells themselves, the scaffold surrounding the stem cell, and the media used to expand and differentiate the stem cells. This paper will examine the recent advancements in technology for each of these relating to the development of an artificial stem cell niche. Many key aspects of the artificial niche need to be improved on before we can scale up the engineered device for large scale blood production including more efficient methods of retrieval of the embroid bodies produced from the microfluidic channels. The current state of experimental methods such as these as well as relevant discoveries in related fields that could be applied to artificial niche technology is described in this paper. Furthermore, we present a mathematical model to describe cell expansion in the artificial hematopoietic stem cell niche in order to design and optimize a scaled-up bioreactor. The mathematical model describes the dynamics of expansion, and maintenance of homeostasis in the bioreactor.


Assuntos
Células-Tronco Hematopoéticas/citologia , Nicho de Células-Tronco , Engenharia Tecidual/métodos , Técnicas de Cultura de Células/instrumentação , Humanos , Técnicas Analíticas Microfluídicas , Engenharia Tecidual/instrumentação
9.
Support Care Cancer ; 19(12): 2015-20, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21116652

RESUMO

PURPOSE: Patients with malignancy sometimes develop painful mucositis and require patient-controlled analgesia (PCA) to treat their pain. Pain disrupts sleep and there is some evidence that analgesic medications also disrupt sleep. This study examined whether treatment with the sedative hypnotic eszopiclone could improve self-reports of sleep, fatigue, and pain as well as decrease opioid self-administered via PCA. METHODS: Inpatients who developed mucositis severe enough to require PCA treatment were randomized double-blind to a 2-day trial on eszopiclone or placebo-administered at bedtime. Patients completed questionnaires which assessed sleep, pain, and fatigue. PCA medication was calculated in terms of morphine equivalents. Data were analyzed with unpaired t tests and repeated measures analysis of variance. RESULTS: Twenty-two patients were randomized to placebo and 23 to eszopiclone. Groups were comparable in age and treatment characteristics. Mean pain scores were lower in the eszopiclone group at all time points (morning p = 0.01, afternoon p = 0.04, evening p = 0.04). The eszopiclone group reported increased sleep time (p < 0.05), fewer nighttime awakenings (p < 0.001), better self-reported sleep quality (p = 0.01), and depth (p = 0.04). There were no significant differences between eszopiclone and placebo in terms of self-reports of fatigue or opioid usage. CONCLUSION: Sedative hypnotic agents improve sleep and analgesia even in the setting of considerable pain and discomfort.


Assuntos
Compostos Azabicíclicos/uso terapêutico , Fadiga/induzido quimicamente , Hipnóticos e Sedativos/uso terapêutico , Mucosite/etiologia , Dor/tratamento farmacológico , Piperazinas/uso terapêutico , Sono/efeitos dos fármacos , Adulto , Compostos Azabicíclicos/administração & dosagem , Zopiclona , Neoplasias Hematológicas/complicações , Humanos , Hipnóticos e Sedativos/administração & dosagem , Pessoa de Meia-Idade , Mucosite/complicações , Mucosite/fisiopatologia , Dor/etiologia , Piperazinas/administração & dosagem , Inquéritos e Questionários
10.
Cell Immunol ; 263(2): 138-47, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20434139

RESUMO

Induction of tumor-specific immunity is an attractive approach to cancer therapy, however to date every major pivotal trial has resulted in failure. While the phenomena of tumor-mediated immune suppression has been known for decades, only recently have specific molecular pathways been elucidated, and for the first time, rationale means of intervening and observing results of intervention have been developed. In this review we describe major advances in our understanding of tumor escape from immunological pressure and provide some possible therapeutic scenarios for enhancement of efficacy in future cancer vaccine trials.


Assuntos
Antígenos de Neoplasias , Vacinas Anticâncer/imunologia , Vacinas Anticâncer/uso terapêutico , Neoplasias/imunologia , Neoplasias/terapia , Células Dendríticas/imunologia , Humanos , Tolerância Imunológica/imunologia , Estresse Oxidativo , Linfócitos T/imunologia
11.
J Transl Med ; 8: 16, 2010 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-20158898

RESUMO

The medical use of low level laser (LLL) irradiation has been occurring for decades, primarily in the area of tissue healing and inflammatory conditions. Despite little mechanistic knowledge, the concept of a non-invasive, non-thermal intervention that has the potential to modulate regenerative processes is worthy of attention when searching for novel methods of augmenting stem cell-based therapies. Here we discuss the use of LLL irradiation as a "photoceutical" for enhancing production of stem cell growth/chemoattractant factors, stimulation of angiogenesis, and directly augmenting proliferation of stem cells. The combination of LLL together with allogeneic and autologous stem cells, as well as post-mobilization directing of stem cells will be discussed.


Assuntos
Terapia com Luz de Baixa Intensidade , Doença Pulmonar Obstrutiva Crônica/terapia , Células-Tronco , Animais , Diferenciação Celular/efeitos da radiação , Proliferação de Células/efeitos da radiação , Ensaios Clínicos como Assunto , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Neovascularização Fisiológica/efeitos da radiação , Transplante de Células-Tronco , Células-Tronco/fisiologia , Células-Tronco/efeitos da radiação
12.
Biol Blood Marrow Transplant ; 16(5): 587-94, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-19895894

RESUMO

Recent years have brought significant breakthroughs in the understanding of tumor biology, related to discovery of cancer stem cells (CSCs) in acute myelogenous leukemia as well as in a number of solid tumors. This finding revealed that not all tumor cells are able to divide indefinitely, and that the bulk of tumor cells are expanded because of divisions and differentiation of CSC fraction. Although the CSCs identified in acute leukemia have a phenotype of early hematopoietic progenitors, it seems that CSCs in multiple myeloma (MM) may resemble the memory B cell fraction. Previous studies in patients with MM have documented the existence of cells without plasma cell characteristics expressing MM-type immunoglobulin genes--so-called "clonotypic" B cells. These cells have been characterized functionally and phenotypically as chemoresistant recirculating B cells. They have been found to self-renew and to be capable of initiating MM growth in immunocompromised animals. Controversy exists as to whether these cells truly belong to an MM clone, however; they may represent only the remaining clones of premalignant B cells. The identification of MM stem cells responsible for the recurrence of MM is of primary importance in designing targeted therapies to definitely cure this disease. This article summarizes the current state of knowledge on these hypothetical "MM stem cells."


Assuntos
Mieloma Múltiplo/patologia , Células-Tronco Neoplásicas/patologia , Linfócitos B/patologia , Células Clonais/patologia , Humanos
13.
Biol Blood Marrow Transplant ; 15(10): 1306-13, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19747639

RESUMO

Autologous peripheral blood stem/progenitor cell transplantation (APBSCT) has been investigated as a potential therapeutic option to improve outcome in patients with acute myelogenous leukemia (AML). However, its optimal role in treatment for adults in remission has not been clearly established. We performed a retrospective analysis on 45 patients aged 21 to 73 years (median 51 years) with de novo AML who underwent APBSCT stratified by age, complete remission status, and cytogenetic risk. The 5-year disease-free survival (DFS) for all patients was 33.9% (95% confidence interval [CI], 20.1%-53.7%) and overall survival (OS) was 43.6% (CI, 29.2%-62.8%). For patients under the age of 60 years, the 5-year DFS for intermediate and high cytogenetic risk was 53.3% (CI, 23.5%-85.6%) and 50.0% (CI, 16.1%-100.0%); the 5-year OS for patients under the age of 60 years with low, intermediate, and high cytogenetic risk was 80.0% (CI, 40.0%-100.0%), 60.0% (CI, 31.2%-90.7%), and 75.0% (CI, 39.0%-100.0%), respectively. For patients over the age of 60 years, the 5-year DFS and OS for intermediate cytogenetic risk was 21.4% (CI, 7.9%-58.4%) and 21.4% (CI, 7.9%-58.4%). The DFS and OS of these patients are comparable to the historic survival of those who underwent allogeneic stem cell transplantation when adjusted by age. In addition, there was no treatment-related mortality (TRM). We conclude that APBSCT is a reasonable and safe intensive consolidation for patients with AML who do not have a suitable HLA-matched donor.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda/mortalidade , Leucemia Mieloide Aguda/terapia , Adulto , Fatores Etários , Idoso , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida , Fatores de Tempo , Transplante Autólogo
14.
J Transl Med ; 7: 27, 2009 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-19386101

RESUMO

BACKGROUND: It has been suggested that the initial differentiation of endothelial and hematopoietic cells during embryogenesis occurs from a common progenitor, called hemangioblast (hB). We hypothesized that these cells with dual hematopoietic/endothelial potential could be used in future regenerative medicine. METHODS: We used the two-step differentiation technology to generate bipotential blast cells from human embryonic stem cells (hES). This involved short differentiation in our in vitro EB system followed by differentiation in semisolid culture medium supplemented with mixture of cytokines. RESULTS: The occurrence of blast-colony-forming cells (BL-CFC) during EB differentiation (day 0-6) was transient and peaked on day 3. The emergence of this event was associated with expression of mesoderm gene T, and inversely correlated with expression of endoderm gene FoxA2. Similarly, the highest BL-CFC number was associated with increase in expression of early hematopoietic/endothelial genes: CD34, CD31 and KDR. The derived colonies were composed of 30-50 blast cells on day 6 in culture. These cells had homogenous appearance in Wright-Giemsa stain, but to a different extent expressed markers of immature hematopoietic and endothelial cells (CD31, CD34, VE-cadherin, Flt-1) and mature differentiated cells (CD45, CD33, CD146). We found that some of them expressed fetal and embryonic globin genes. Interestingly, these cells expressed also HLA class I molecules, however at very low levels compared to endothelial and hematopoietic cells. The blast cells could be successfully differentiated to hematopoietic cells in a CFU assay. In these conditions, blast cells formed CFU-M colonies (63.4 +/- 0.8%) containing macrophages, BFU-E colonies (19.5 +/- 3.5%) containing nucleated red blood cells, and CFU-EM colonies (17.1 +/- 2.7%) composed of macrophages and nucleated erythrocytes. Cells of CFU-EM and BFU-E colonies expressed both epsilon - and gamma- globin genes, but not adult-type gamma-globin. When in endothelial cell culture conditions, blast cells differentiated to endothelial cells which had the ability to take up Dil-Ac-LDL and to form complex vascular networks in Matrigel. CONCLUSION: 1) Hematoendothelial precursors exist transiently in early embryonic development and form single cell-derived colonies; 2) their differentiation can be tracked by the use of chosen molecular markers; 3) blast colonies consist of cells having properties of endothelial and hematopoietic precursors, however the issue of their ability to maintain dual properties over time needs to be further explored; 4) blast cells can potentially be used in regenerative medicine due to their low expression of HLA molecules.


Assuntos
Células-Tronco Embrionárias/imunologia , Antígenos HLA-A/genética , Hemangioblastos/imunologia , Vasos Sanguíneos/embriologia , Vasos Sanguíneos/crescimento & desenvolvimento , Diferenciação Celular , Divisão Celular , Colágeno , Combinação de Medicamentos , Desenvolvimento Embrionário , Células-Tronco Embrionárias/citologia , Células Endoteliais/citologia , Células Endoteliais/fisiologia , Imunofluorescência , Hemangioblastos/citologia , Hematopoese , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/fisiologia , Humanos , Laminina , Proteoglicanas
15.
Curr Pharm Biotechnol ; 10(3): 345-6, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19355944

RESUMO

"Niche" is defined as a specialized regulatory microenvironment, consisting of components which control the fate specification of stem and progenitor cells, as well as maintaining their development by supplying the requisite factors. Bone marrow (BM) niche has a well-organized architecture and is composed of osteoblasts, osteoclasts, bone marrow endothelial cells, stromal cells, adipocytes and extracellular matrix proteins (ECM). These elements play an essential role in the survival, growth and differentiation of diverse lineages of blood cells, but also provide optimal growth environment for multiple hematological malignancies including multiple myeloma (MM). MM is a neoplastic plasma cell disorder which not only resides in BM but also converts it into specialized neoplastic niche. This niche aids the growth and spreading of tumor cells by a complex interplay of cytokines, chemokines, proteolytic enzymes and adhesion molecules. Moreover, the MM BM microenvironment was shown to confer survival and chemoresistance of MM cells to current therapies. However, our knowledge in this field is still in infancy and many details are unknown. Therefore, there is a strong need to further dissect the MM BM niche and understand the process of how the complex interactions with BM milieu influence MM growth, survival and development of resistance to chemotherapy. A better and more detailed understanding of neoplastic MM niche will provide a guiding model for identifying and validating novel targeted therapies directed against MM. Therefore, in the present review, we have focused principally on the basic features, physical structures, and functions of the BM niche and have highlighted its interaction with MM cells.


Assuntos
Medula Óssea/patologia , Mieloma Múltiplo/patologia , Adipócitos/fisiologia , Animais , Células Dendríticas/fisiologia , Células Endoteliais/fisiologia , Matriz Extracelular/patologia , Humanos , Osteoblastos/fisiologia , Osteoclastos/fisiologia , Células Estromais/metabolismo , Células Estromais/patologia
16.
Cell Cycle ; 8(4): 606-10, 2009 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-19197154

RESUMO

Animal studies have demonstrated that selective tropism of mesenchymal stem cells (MSC) for glioma may be used as a means of selective delivery of cytotoxic payloads. Endometrial Regenerative Cells (ERC) are a population of mesenchymal-like cells which possesse pluripotent differentiation capacity and is characterized by unique surface markers and growth factor production. In this study we sought to determine whether unmanipulated ERC would alter the growth of glioma using the aggressive C6/LacZ7 (C6) into Sprague Dawley rat model. ERC administration by intravenous (i.v.) or intratumoral (i.t.) showed significant inhibition of glioma: volume reduction of 49% after i.v. treatment (p < 0.05), and about 46% i.t. treatment (p < 0.05). Tumor reduction was associated with inhibition of angiogenesis and reduced numbers of CD133 positive cells in the incranial tumor. Despite the angiogenic potential of ERC in the hindlimb ischemia model, these data support a paradoxical tumor inhibitory activity of ERC. Further studies are needed to determine the qualitative differences between physiological angiogenesis, which seems to be supported by ERC and tumor angiogenesis which appeared to be inhibited.


Assuntos
Endométrio , Glioma , Regeneração/fisiologia , Animais , Antígenos CD/metabolismo , Endométrio/citologia , Endométrio/fisiologia , Feminino , Glioma/patologia , Glioma/fisiopatologia , Humanos , Masculino , Mesotelina , Transplante de Neoplasias , Ratos , Ratos Sprague-Dawley
17.
Blood ; 113(12): 2646-54, 2009 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-19164600

RESUMO

Translation of small interfering RNA (siRNA)-based approaches into practical therapeutics is limited because of lack of an effective and cell-specific delivery system. Herein, we present a new method of selectively delivering siRNA to dendritic cells (DCs) in vivo using CD40 siRNA-containing immunoliposomes (siILs) that were decorated with DC-specific DEC-205 mAb. Administration of CD40 siILs resulted in DC-specific cell targeting in vitro and in vivo. On treatment with CD40 siILs, the expression of CD40 in DCs, as well allostimulatory activity was inhibited. In vivo administration resulted in selective siRNA uptake into immune organs and functional immune modulation as assessed using a model antigen. In conclusion, this is the first demonstration of DC-specific siRNA delivery and gene silencing in vivo, which highlights the potential of DC-mediated immune modulation and the feasibility of siRNA-based clinical therapy.


Assuntos
Apresentação de Antígeno/efeitos dos fármacos , Antígenos CD40/antagonistas & inibidores , Células Dendríticas/efeitos dos fármacos , Terapia Genética/métodos , Terapia de Imunossupressão/métodos , Interferência de RNA , RNA Interferente Pequeno/administração & dosagem , Animais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/imunologia , Antígenos CD/imunologia , Células da Medula Óssea/citologia , Antígenos CD40/biossíntese , Antígenos CD40/genética , Antígenos CD40/imunologia , Células Cultivadas/efeitos dos fármacos , Células Cultivadas/imunologia , Células Dendríticas/imunologia , Sistemas de Liberação de Medicamentos , Imunoconjugados/administração & dosagem , Lectinas Tipo C/imunologia , Lipossomos , Ativação Linfocitária/efeitos dos fármacos , Tecido Linfoide/efeitos dos fármacos , Tecido Linfoide/ultraestrutura , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Antígenos de Histocompatibilidade Menor , RNA Interferente Pequeno/farmacologia , RNA Interferente Pequeno/uso terapêutico , Receptores de Superfície Celular/imunologia , Linfócitos T/imunologia
18.
Blood ; 113(7): 1581-8, 2009 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-18974373

RESUMO

Relapse of malignancy after allogeneic hematopoietic cell transplantation (allo-HCT) remains a therapeutic challenge. Blockade of the CTLA4 molecule can effectively augment antitumor immunity mediated by autologous effector T cells. We have assessed the safety and preliminary efficacy of a neutralizing, human anti-CTLA4 monoclonal antibody, ipilimumab, in stimulating the graft-versus-malignancy (GVM) effect after allo-HCT. Twenty-nine patients with malignancies that were recurrent or progressive after allo-HCT, received ipilimumab as a single infusion at dose cohorts between 0.1 and 3.0 mg/kg. Dose-limiting toxicity was not encountered, and ipilimumab did not induce graft-versus-host disease (GVHD) or graft rejection. Organ-specific immune adverse events (IAE) were seen in 4 patients (grade 3 arthritis, grade 2 hyperthyroidism, recurrent grade 4 pneumonitis). Three patients with lymphoid malignancy developed objective disease responses following ipilimumab: complete remission (CR) in 2 patients with Hodgkin disease and partial remission (PR) in a patient with refractory mantle cell lymphoma. At the 3.0 mg/kg dose, active serum concentrations of ipilimumab were maintained for more than 30 days after a single infusion. Ipilimumab, as administered in this clinical trial, does not induce or exacerbate clinical GVHD, but may cause organ-specific IAE and regression of malignancy. This study is registered at (http://clinicaltrials.gov) under NCI protocol ID P6082.


Assuntos
Transferência Adotiva , Anticorpos Monoclonais/administração & dosagem , Antígenos CD/metabolismo , Efeito Enxerto vs Leucemia/efeitos dos fármacos , Leucemia/terapia , Recidiva Local de Neoplasia/prevenção & controle , Adulto , Idoso , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais/farmacocinética , Antígenos CD/imunologia , Artrite Reumatoide/induzido quimicamente , Antígeno CTLA-4 , Feminino , Doença Enxerto-Hospedeiro/etiologia , Humanos , Ipilimumab , Estimativa de Kaplan-Meier , Leucemia/mortalidade , Linfoma/mortalidade , Linfoma/terapia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/mortalidade , Pneumonia/induzido quimicamente , Transplante Homólogo
19.
J Transl Med ; 6: 45, 2008 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-18713449

RESUMO

Critical limb ischemia (CLI) is an advanced form of peripheral artery disease which is responsible for approximately 100,000 amputations per year in the US. Trials to date have reported clinical improvement and reduced need for amputation in CLI patients receiving autologous bone marrow or mobilized peripheral blood stem cells for stimulation of angiogenesis. While such treatments are currently entering Phase III trials, practical and scientific pitfalls will limit widespread implementation if efficacy is proven. Hurdles to be overcome include: a) reduced angiogenic potential of autologous cells in aged patients with cardiovascular risk factors; b) invasiveness/adverse effects of bone marrow extraction and G-CSF mobilization, respectively; and c) need for on-site cellular manipulation. The Endometrial Regenerative Cell (ERC) is a mesenchymal-like stem cell derived from the menstrual blood that is believed to be associated with endometrial angiogenesis. We discuss the possibility of using allogeneic ERCs as an "off the shelf" treatment for CLI based on the following properties: a) High levels of growth factors and matrix metalloprotease production; b) Ability to inhibits inflammatory responses and lack of immunogenicity; and c) Expandability to great quantities without loss of differentiation ability or karyotypic abnormalities.


Assuntos
Endométrio/citologia , Endométrio/transplante , Isquemia/terapia , Perna (Membro)/irrigação sanguínea , Regeneração , Animais , Feminino , Humanos , Neovascularização Fisiológica , Transplante Homólogo
20.
Curr Pharm Biotechnol ; 8(5): 305-17, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17979728

RESUMO

Cellular therapies derived from embryonic stem (ES) cells have gained a renewed interest with the experimental demonstration that an embryonic stem cell lines can be established from human blastocyst-stage embryos and prompted to differentiate into almost all types of cells present in the body including hematopoietic cells. Hematopoiesis is a series of cellular processes whereby short-lived mature blood cells are continuously replenished from a pool of rare pluripotential hematopoietic stem cells, in a highly orchestrated process. Aberrances in this intricate process may lead to a malignancy of essential blood-forming organs, causing diseases such as leukemia, aplastic anemia, lymphoma, myelodysplasia and myeloproliferative disorders. Embryonic stem cells show great potential and it may be technologically feasible to transplant differentiated ES cells and to cure various kinds of blood disorders. Understanding the biology of ES cell derived hematopoiesis may lead to the development of co-transplantation protocols that will result in a decreased morbidity and mortality by providing safer and simpler transplantation procedures for patients with malignant and non-malignant conditions. The potential utility of ES cells for gene therapy, tissue engineering and the treatment of a wide variety of currently untreatable diseases is simply too essential to ignore, however, our knowledge and ability to deliver these forms of therapy in a safe and efficient manner requires additional advances in the understanding of the basic biology of ES cells. In this article, we will discuss the factors and methodologies responsible for the differentiation of ES cells into hematopoietic progenitors and their potential to treat different blood related diseases.


Assuntos
Células-Tronco Embrionárias/transplante , Doenças Hematológicas/cirurgia , Transplante de Células-Tronco Hematopoéticas/tendências , Animais , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/fisiologia , Doenças Hematológicas/patologia , Hematopoese/fisiologia , Transplante de Células-Tronco Hematopoéticas/métodos , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/fisiologia , Humanos
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