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1.
Polymers (Basel) ; 14(17)2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-36080673

RESUMO

Nanotechnology is a powerful tool and fast-growing research area in many novel arenas, ranging from biomedicine to engineering and energy storage. Nanotechnology has great potential to make a significant positive contribution in forensic science, which deals with the identification and investigation of crimes, finding relationships between pieces of evidence and perpetrators. Nano-forensics is related to the development of nanosensors for crime investigations and inspection of terrorist activity by analyzing the presence of illicit drugs, explosives, toxic gases, biological agents, and so forth. In this regard, carbon nanomaterials have huge potential for next-generation nanosensors due to their outstanding properties, including strength combined with flexibility, large specific surface area, high electrical conductivity, and little noise. Moreover, their combination with polymers can provide nanocomposites with novel and enhanced performance owed to synergy between the composite components. This review concisely recapitulates up-to-date advances in the development of polymer composites incorporating carbon-based nanomaterials for forensic science. The properties of the different carbon nanomaterials, several methods used to analyze functional polymeric nanocomposites, and their applications in forensic investigation are discussed. Furthermore, present challenges and forthcoming outlooks on the design of new polymer/carbon nanomaterial composites for crime prevention are highlighted.

2.
Br J Haematol ; 187(1): 93-104, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31172513

RESUMO

Patients with low-risk myelodysplastic syndromes (MDS) usually develop iron overload. This leads to a high level of oxidative stress in the bone marrow (BM) and increases haematopoietic cell dysfunction. Our objective was to analyse whether chelation with deferasirox (DFX) alleviates the consequences of oxidative stress and improves BM cell functionality. We analysed 13 iron-overloaded MDS patients' samples before and 4-10 months after treatment with DFX. Using multiparametric flow cytometry analysis, we measured intracellular reactive oxygen species (ROS), DNA oxidation and double strand breaks. Haematopoietic differentiation capacity was analysed by colony-forming unit (CFU) assays. Compared to healthy donors, MDS showed a higher level of intracellular ROS and DNA oxidative damage in BM cells. DNA oxidative damage decreased following DFX treatment. Furthermore, the clonogenic assays carried out before treatment suggest an impaired haematopoietic differentiation. DFX seems to improve this capacity, as illustrated by a decreased cluster/CFU ratio, which reached values similar to controls. We conclude that BM cells from MDS are subject to higher oxidative stress conditions and show an impaired haematopoietic differentiation. These adverse features seem to be partially rectified after DFX treatment.


Assuntos
Dano ao DNA/efeitos dos fármacos , Deferasirox/uso terapêutico , Quelantes de Ferro/uso terapêutico , Síndromes Mielodisplásicas/tratamento farmacológico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/metabolismo , Células da Medula Óssea/fisiologia , Estudos de Casos e Controles , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Deferasirox/farmacologia , Humanos , Quelantes de Ferro/farmacologia , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/etiologia , Sobrecarga de Ferro/genética , Sobrecarga de Ferro/metabolismo , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/complicações , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/metabolismo , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Estudos Prospectivos , Espécies Reativas de Oxigênio/metabolismo , Células-Tronco/efeitos dos fármacos , Células-Tronco/fisiologia , Adulto Jovem
3.
Stem Cell Res Ther ; 10(1): 63, 2019 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-30795797

RESUMO

BACKGROUND: Posterolateral spinal fusion with autologous bone graft is considered the "gold standard" for lumbar degenerative disc disease (DDD) when surgical treatment is indicated. The potential role of mesenchymal stromal cells (MSCs) to replace the bone graft in this setting has not been fully addressed. OBJECTIVE: To analyze the safety, feasibility and potential clinical efficacy of the implantation of autologous MSCs embedded with tricalcium phosphate as a therapeutic alternative to bone graft in patients with DDD during posterolateral spine fusion. STUDY DESIGN: Phase I/II single-arm prospective clinical trial. METHODS: Eleven patients with monosegmental DDD at L4-L5 or L5-S1 level were included. Autologous bone marrow-derived MSC were expanded in our Good Manufacturing Practice (GMP) Facility and implanted during spinal surgery embedded in a tricalcium phosphate carrier. Monitoring of patients included a postoperative period of 12 months with four visits (after the 1st, 3rd, 6th, and 12th month), with clinical and radiological assessment that included the visual analog scale (VAS), the Oswestry disability index (ODI), the Short-Form Health Survey (SF-36), the vertebral fusion grade observed through a simple Rx, and the evaluation of possible complications or adverse reactions. In addition, all patients were further followed up to 5 years for outcome. RESULTS: Median age of patients included was 44 years (range 30-58 years), and male/female ratio was (6/5) L4-L5 and L5-S1 DDD was present five and six patients, respectively. Autologous MSCs were expanded in all cases. There were no adverse effects related to cell implantation. Regarding efficacy, both VAS and ODI scores improved after surgery. Radiologically, 80% of patients achieved lumbar fusion at the end of the follow-up. No adverse effects related to the procedure were recorded. CONCLUSIONS: The use of autologous MSCs for spine fusion in patients with monosegmental degenerative disc disease is feasible, safe, and potentially effective. TRIAL REGISTRATION: no. EudraCT: 2010-018335-17 ; code Identifier: NCT01513694 ( clinicaltrials.gov ).


Assuntos
Degeneração do Disco Intervertebral/terapia , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais , Fusão Vertebral , Adolescente , Adulto , Idoso , Fosfatos de Cálcio/química , Fosfatos de Cálcio/uso terapêutico , Terapia Baseada em Transplante de Células e Tecidos , Feminino , Seguimentos , Humanos , Degeneração do Disco Intervertebral/fisiopatologia , Região Lombossacral/fisiopatologia , Masculino , Pessoa de Meia-Idade , Transplante Autólogo/métodos , Adulto Jovem
4.
Br J Haematol ; 184(5): 797-807, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30548583

RESUMO

We conducted a phase 2 trial to evaluate the safety and efficacy of bendamustine instead of BCNU (carmustine) in the BEAM (BCNU, etoposide, cytarabine and melphalan) regimen (BendaEAM) as conditioning for autologous stem-cell transplantation (ASCT) in patients with aggressive lymphomas. The primary endpoint was 3-year progression-free survival (PFS). Sixty patients (median age 55 [28-71] years) were included. All patients (except one who died early) engrafted after a median of 11 (9-72) and 14 (4-53) days to achieve neutrophil and platelet counts of >0.5 × 109 /l and >20 × 109 /l, respectively. Non-relapse mortality at 100 days and 1 year were 3.3% and 6.7%, respectively. With a median follow-up of 67 (40-77) months, the estimated 3-year PFS and overall survival (OS) were 58% and 75%, respectively. Patients in partial response at study entry had significantly worse PFS and OS than patients who underwent ASCT in complete metabolic remission, and this was the only prognostic factor associated with both PFS (Relative risk [RR], 0.27 [95% confidence interval {CI} [0.12-0.56]) and OS (RR, 0.40 [95% CI 0.17-0.97]) in the multivariate analysis. BendaEAM conditioning is therefore a feasible and effective regimen in patients with aggressive lymphomas. However, patients not in complete metabolic remission at the time of transplant had poorer survival and so should be considered for alternative treatment strategies.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Cloridrato de Bendamustina/administração & dosagem , Linfoma/mortalidade , Linfoma/terapia , Transplante de Células-Tronco de Sangue Periférico , Condicionamento Pré-Transplante , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Autoenxertos , Cloridrato de Bendamustina/efeitos adversos , Carmustina/administração & dosagem , Carmustina/efeitos adversos , Citarabina/administração & dosagem , Citarabina/efeitos adversos , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Melfalan/administração & dosagem , Melfalan/efeitos adversos , Pessoa de Meia-Idade , Podofilotoxina/administração & dosagem , Podofilotoxina/efeitos adversos , Taxa de Sobrevida
5.
Eur J Haematol ; 2018 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-30084111

RESUMO

OBJECTIVE: No standard second-line treatment exists for acute graft-versus-host disease steroid-refractory (SR-aGvHD), and long-term outcomes remain poor. Mesenchymal stromal cells (MSCs) have been evaluated as treatment, but no disease model (DM) exists that integrates and extrapolates currently available evidence. The aim of this study was to develop such a DM to describe the natural history of SR-aGvHD and to predict long-term outcomes. METHOD: The DM was developed in collaboration with experts in haematology-oncology. Subsequently, a model simulation was run. Input parameters for transition and survival estimates were informed by published data of clinical trials on MSC treatment for SR-aGvHD. Parametric distributions were used to estimate long-term survival rates after MSCs. RESULTS: The newly developed DM is a cohort model that consists of eight health states. For the model simulation, we obtained data on 327 patients from 14 published phase II trials. Due to limited evidence, DM structure was simplified and several assumptions had to be made. Median overall survival was 3.2 years for complete response and 0.5 years for no complete response. CONCLUSION: The DM provides a comprehensive overview on the second-line treatment pathway for aGvHD and enables long-term predictions that can be used to perform a cost-effectiveness analysis comparing any treatment for SR-aGvHD.

6.
Stem Cell Res Ther ; 9(1): 150, 2018 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-29848379

RESUMO

Thromboangiitis obliterans (TAO), also known as Buerger's Disease, is an occlusive vasculitis linked with high morbidity and amputation risk. To date, TAO is deemed incurable due to the lack of a definitive treatment. The immune system and inflammation are proposed to play a central role in TAO pathogenesis. Due to their immunomodulatory effects, mesenchymal stromal cells (MSCs) are the subject of intense research for the treatment of a wide range of immune-mediated diseases. Thus far, local intramuscular injections of autologous or allogeneic MSCs have shown promising results in TAO. However, sequential intravenous allogeneic MSC administration has not yet been explored, which we hypothesized could exert a systemic anti-inflammatory effect in the vasculature and modulate the immune response. Here, we report the first case of a TAO patient at amputation risk treated with four sequential intravenous infusions of bone marrow-derived allogeneic MSCs from a healthy donor. Following administration, there was significant regression of foot skin ulcers and improvements in rest pain, Walking Impairment Questionnaire scores, and quality of life. Sixteen months after the infusion, the patient had not required any further amputations. This report highlights the potential of sequential allogeneic MSC infusions as an effective treatment for TAO, warranting further studies to compare this approach with the more conventionally used intramuscular MSC administration and other cell-based therapies.


Assuntos
Transplante de Células-Tronco Mesenquimais/métodos , Tromboangiite Obliterante/terapia , Transplante Homólogo/métodos , Administração Intravenosa , Adulto , Humanos , Masculino , Células-Tronco Mesenquimais , Tromboangiite Obliterante/patologia , Resultado do Tratamento
7.
PLoS One ; 12(8): e0182470, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28796790

RESUMO

There is evidence of continuous bidirectional cross-talk between malignant cells and bone marrow-derived mesenchymal stromal cells (BM-MSC), which favors the emergence and progression of myeloproliferative neoplastic (MPN) diseases. In the current work we have compared the function and gene expression profile of BM-MSC from healthy donors (HD-MSC) and patients with MPN (JAK2V617F), showing no differences in the morphology, proliferation and differentiation capacity between both groups. However, BM-MSC from MPN expressed higher mean fluorescence intensity (MIF) of CD73, CD44 and CD90, whereas CD105 was lower when compared to controls. Gene expression profile of BM-MSC showed a total of 169 genes that were differentially expressed in BM-MSC from MPN patients compared to HD-MSC. In addition, we studied the ability of BM-MSC to support the growth and survival of hematopoietic stem/progenitor cells (HSPC), showing a significant increase in the number of CFU-GM colonies when MPN-HSPC were co-cultured with MPN-MSC. Furthermore, MPN-MSC showed alteration in the expression of genes associated to the maintenance of hematopoiesis, with an overexpression of SPP1 and NF-kB, and a downregulation of ANGPT1 and THPO. Our results suggest that BM-MSC from JAK2+ patients differ from their normal counterparts and favor the maintenance of malignant clonal hematopoietic cells.


Assuntos
Neoplasias Hematológicas/patologia , Janus Quinase 2/metabolismo , Células-Tronco Mesenquimais/fisiologia , Adulto , Idoso , Apoptose , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Ciclo Celular , Linhagem Celular Tumoral , Técnicas de Cocultura , Feminino , Expressão Gênica , Neoplasias Hematológicas/sangue , Neoplasias Hematológicas/enzimologia , Hematopoese , Humanos , Masculino , Pessoa de Meia-Idade
8.
Oncotarget ; 8(17): 28187-28202, 2017 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-28390197

RESUMO

Histone deacetylases (HDACs) are involved in epigenetic modulation and their aberrant expression has been demonstrated in myeloproliferative neoplasms (MPN). HDAC8 inhibition has been shown to inhibit JAK2/STAT5 signaling in hematopoietic cells from MPN. Nevertheless, the role of HDAC8 expression in bone marrow-mesenchymal stromal cells (BM-MSC) has not been assessed. In the current work we describe that HDAC8 is significantly over-expressed in MSC from in JAK-2 positive MPN compared to those from healthy-donors (HD-MSC). Using a selective HDAC8 inhibitor (PCI34051), we verified that the subsequent decrease in the protein and mRNA expression of HDAC8 is linked with an increased apoptosis of malignant MSC whereas it has no effects on normal MSC. In addition, HDAC8 inhibition in MPN-MSC also decreased their capacity to maintain neoplastic hematopoiesis, by increasing the apoptosis, cell-cycle arrest and colony formation of JAK2+-hematopoietic cells. Mechanistic studies using different MPN cell lines revealed that PCI34051 induced their apoptosis, which is enhanced when were co-cultured with JAK2V617F-MSC, decreased their colony formation and the phosphorylation of STAT3 and STAT5. In summary, we show for the first time that the inhibition of HDAC8 in MSC from JAK2+ MPN patients selectively decreases their hematopoietic-supporting ability, suggesting that HDAC8 may be a potential therapeutic target in this setting by acting not only on hematopoietic cells but also on the malignant microenvironment.


Assuntos
Histona Desacetilases/genética , Janus Quinase 2/metabolismo , Células-Tronco Mesenquimais/metabolismo , Transtornos Mieloproliferativos/genética , Proteínas Repressoras/genética , Apoptose/efeitos dos fármacos , Células da Medula Óssea/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular/efeitos dos fármacos , Expressão Gênica , Hematopoese/efeitos dos fármacos , Inibidores de Histona Desacetilases/farmacologia , Histona Desacetilases/metabolismo , Humanos , Janus Quinase 2/genética , Células-Tronco Mesenquimais/efeitos dos fármacos , Terapia de Alvo Molecular , Mutação , Transtornos Mieloproliferativos/tratamento farmacológico , Transtornos Mieloproliferativos/metabolismo , Proteínas Repressoras/antagonistas & inibidores , Proteínas Repressoras/metabolismo , Fator de Transcrição STAT3/metabolismo , Fator de Transcrição STAT5/metabolismo
9.
Br J Haematol ; 173(2): 245-52, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26847165

RESUMO

Diffuse large B-cell lymphoma (DLBCL) patients failing rituximab-containing therapy have a poor outcome with the current salvage regimens. We conducted a phase 1b trial to determine the maximum tolerated dose (MTD) of lenalidomide in combination with R-ESHAP (rituximab, etoposide, cisplatin, cytarabine, methylprednisolone) (LR-ESHAP) in patients with relapsed or refractory DLBCL. Efficacy data were collected as a secondary objective. Subjects received 3 cycles of lenalidomide at escalating doses (5, 10 or 15 mg) given on days 1-14 of every 21-day cycle, in combination with R-ESHAP. Responding patients received BEAM (carmustine, etoposide, cytarabine, melphalan) followed by autologous stem-cell transplantation. Lenalidomide 10 mg/d was identified as the MTD because, in the 15 mg cohort, one patient experienced dose-limiting toxicity (grade 3 angioedema) and two patients had mobilization failure. A total of 19 patients (3, 12 and 4 in the 5, 10 and 15 mg cohorts, respectively) were evaluable. All toxicities occurring during LR-ESHAP cycles resolved appropriately and no grade 4-5 non-haematological toxicities were observed. The complete remission and overall response rates were 47·4% and 78·9%, respectively. With a median follow-up of 24·6 (17·4-38·2) months, the 2-year progression-free survival and overall survival were 44% and 63%, respectively. In conclusion, the LR-ESHAP regimen is feasible and yields encouraging outcomes.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Adolescente , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Doença Crônica , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Citarabina/administração & dosagem , Citarabina/efeitos adversos , Relação Dose-Resposta a Droga , Etoposídeo/administração & dosagem , Etoposídeo/efeitos adversos , Feminino , Humanos , Lenalidomida , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Prednisona/administração & dosagem , Prednisona/efeitos adversos , Indução de Remissão/métodos , Terapia de Salvação/métodos , Talidomida/administração & dosagem , Talidomida/efeitos adversos , Talidomida/análogos & derivados , Resultado do Tratamento , Adulto Jovem
10.
Cell Commun Signal ; 14: 2, 2016 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-26754424

RESUMO

BACKGROUND: Human mesenchymal stromal cells (hMSC) are multipotent cells with both regenerative and immunomodulatory activities making them an attractive tool for cellular therapy. In the last few years it has been shown that the beneficial effects of hMSC may be due to paracrine effects and, at least in part, mediated by extracellular vesicles (EV). EV have emerged as important mediators of cell-to-cell communication. Flow cytometry (FCM) is a routine technology used in most clinical laboratories and could be used as a methodology for hMSC-EV characterization. Although several reports have characterized EV by FCM, a specific panel and protocol for hMSC-derived EV is lacking. The main objective of our study was the characterization of hMSC-EV using a standard flow cytometer. METHODS: Human MSC from bone marrow of healthy donors, mesenchymal cell lines (HS-5 and hTERT) and a leukemic cell line (K562 cells) were used to obtain EV for FCM characterization. EV released from the different cell lines were isolated by ultracentrifugation and were characterized, using a multi-parametric analysis, in a conventional flow cytometer. EV characterization by transmission electron microscopy (TEM), western blot (WB) and Nano-particle tracking analysis (NTA) was also performed. RESULTS: EV membranes are constituted by the combination of specific cell surface molecules depending on their cell of origin, together with specific proteins like tetraspanins (e.g. CD63). We have characterized by FCM the EV released from BM-hMSC, that were defined as particles less than 0.9 µm, positive for the hMSC markers (CD90, CD44 and CD73) and negative for CD34 and CD45 (hematopoietic markers). In addition, hMSC-derived EV were also positive for CD63 and CD81, the two characteristic markers of EV. To validate our characterization strategy, EV from mesenchymal cell lines (hTERT/HS-5) were also studied, using the leukemia cell line (K562) as a negative control. EV released from mesenchymal cell lines displayed the same immunophenotypic profile as the EV from primary BM-hMSC, while the EV derived from K562 cells did not show hMSC markers. We further validated the panel using EV from hMSC transduced with GFP. Finally, EV derived from the different sources (hMSC, hTERT/HS-5 and K562) were also characterized by WB, TEM and NTA, demonstrating the expression by WB of the exosomal markers CD63 and CD81, as well as CD73 in those from MSC origin. EV morphology and size/concentration was confirmed by TEM and NTA, respectively. CONCLUSION: We described a strategy that allows the identification and characterization by flow cytometry of hMSC-derived EV that can be routinely used in most laboratories with a standard flow cytometry facility.


Assuntos
5'-Nucleotidase/análise , Vesículas Extracelulares/química , Citometria de Fluxo/métodos , Receptores de Hialuronatos/análise , Células-Tronco Mesenquimais/citologia , Antígenos Thy-1/análise , Adulto , Linhagem Celular , Células Cultivadas , Feminino , Humanos , Masculino , Células-Tronco Mesenquimais/química , Pessoa de Meia-Idade , Adulto Jovem
11.
Biol Blood Marrow Transplant ; 20(10): 1580-5, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24952358

RESUMO

We evaluated the feasibility, safety, and efficacy of the administration of 4 sequential doses (intravenously administered on days 1, 4, 11, and 18) of cryopreserved bone marrow-derived mesenchymal stromal cells (MSC) expanded with platelet lysate and obtained from third-party donors as a second-line treatment for steroid-refractory acute graft-versus-host (aGVHD) disease in a series of 25 patients. All patients received at least 2 doses of MSC, whereas 21 received 3 doses and 18 received the initially planned 4 doses. Because of the achievement of partial response, 4 patients received additional doses of MSC. Median single cell dose administered was 1.1 × 10(6) MSC/kg of recipient body weight. There were no adverse events related to the MSC infusion in the 99 procedures performed, with the exception of a cardiac ischemic event that occurred twice in a patient with prior history of cardiac ischemia. Response to MSC at 60 days after the first dose was evaluable in 24 patients. Seventeen patients (71%) responded (11 complete and 6 partial responses), with a median time to response of 28 days after the first MSC dose, whereas 7 patients did not respond. In summary, we can conclude that sequential cryopreserved third-party MSC therapy administered on days 1, 4, 11, and 18 is a safe procedure for patients with steroid-refractory aGVHD. This strategy may provide a high rate of overall responses of aGVHD with a low toxicity profile.


Assuntos
Criopreservação , Doença Enxerto-Hospedeiro/terapia , Neoplasias Hematológicas/terapia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Condicionamento Pré-Transplante/métodos , Doença Aguda , Adulto , Antineoplásicos/uso terapêutico , Plaquetas/química , Contagem de Células , Resistencia a Medicamentos Antineoplásicos , Feminino , Doença Enxerto-Hospedeiro/imunologia , Doença Enxerto-Hospedeiro/mortalidade , Doença Enxerto-Hospedeiro/patologia , Neoplasias Hematológicas/imunologia , Neoplasias Hematológicas/mortalidade , Neoplasias Hematológicas/patologia , Humanos , Imunossupressores/uso terapêutico , Masculino , Células-Tronco Mesenquimais/imunologia , Pessoa de Meia-Idade , Estudos Prospectivos , Esteroides/uso terapêutico , Análise de Sobrevida , Transplante Homólogo , Resultado do Tratamento , Doadores não Relacionados
12.
PLoS One ; 9(3): e92378, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24658332

RESUMO

Despite recent advances in the treatment of multiple myeloma (MM), it remains an incurable disease potentially due to the presence of resistant myeloma cancer stem cells (MM-CSC). Although the presence of clonogenic cells in MM was described three decades ago, the phenotype of MM-CSC is still controversial, especially with respect to the expression of syndecan-1 (CD138). Here, we demonstrate the presence of two subpopulations--CD138++ (95-99%) and CD138low (1-5%)--in eight MM cell lines. To find out possible stem-cell-like features, we have phenotypically, genomic and functionally characterized the two subpopulations. Our results show that the minor CD138low subpopulation is morphologically identical to the CD138++ fraction and does not represent a more immature B-cell compartment (with lack of CD19, CD20 and CD27 expression). Moreover, both subpopulations have similar gene expression and genomic profiles. Importantly, both CD138++ and CD138low subpopulations have similar sensitivity to bortezomib, melphalan and doxorubicin. Finally, serial engraftment in CB17-SCID mice shows that CD138++ as well as CD138low cells have self-renewal potential and they are phenotypically interconvertible. Overall, our results differ from previously published data in MM cell lines which attribute a B-cell phenotype to MM-CSC. Future characterization of clonal plasma cell subpopulations in MM patients' samples will guarantee the discovery of more reliable markers able to discriminate true clonogenic myeloma cells.


Assuntos
Mieloma Múltiplo/fisiopatologia , Sindecana-1/genética , Sindecana-1/fisiologia , Animais , Ácidos Borônicos/farmacologia , Bortezomib , Linhagem Celular Tumoral , Variações do Número de Cópias de DNA , Doxorrubicina/farmacologia , Xenoenxertos , Humanos , Imunofenotipagem , Melfalan/farmacologia , Camundongos SCID , Mieloma Múltiplo/imunologia , Células-Tronco Neoplásicas , Fenótipo , Plasmócitos/imunologia , Células Precursoras de Linfócitos B , Pirazinas/farmacologia , Sindecana-1/biossíntese
13.
Br J Haematol ; 164(5): 668-74, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24274082

RESUMO

The use of highly effective rituximab-containing therapy for treating diffuse large B-cell lymphoma (DLBCL) makes it more difficult to salvage relapsed or refractory patients. Autologous stem-cell transplantation (ASCT) is the reference treatment for these patients, but the impact of previous exposure to rituximab on the subsequent results of ASCT remains unknown. We analysed 248 patients with relapsed or refractory DLBCL or grade 3B follicular lymphoma pre-treated with rituximab as part of first-line therapy (R+ group) who received ASCT, in comparison with a control group of 127 patients without previous exposure to rituximab (R- group). The complete remission (CR) rates were similar in both groups. Multivariate analysis identified age-adjusted International Prognostic Index at diagnosis, extranodal involvement and disease status at transplant, and the number of previous chemotherapy lines as independent factors with a negative influence on CR rate. Compared with R- patients, those in the R+ group had a significantly better progression-free survival (63% vs. 48% at 5 years) and overall survival (72% vs. 61% at 5 years). This observation was independent of other prognostic factors that affected these outcomes. In conclusion, ASCT is no less effective in patients with relapsed or refractory aggressive B-cell lymphoma pre-treated with first-line rituximab-containing therapy than in rituximab-naive patients.


Assuntos
Anticorpos Monoclonais Murinos/administração & dosagem , Transplante de Medula Óssea , Linfoma Difuso de Grandes Células B/terapia , Adolescente , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Terapia Combinada , Feminino , Sobrevivência de Enxerto/efeitos dos fármacos , Humanos , Estimativa de Kaplan-Meier , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Prognóstico , Recidiva , Indução de Remissão , Estudos Retrospectivos , Rituximab , Terapia de Salvação/métodos , Resultado do Tratamento , Adulto Jovem
14.
Mediterr J Hematol Infect Dis ; 4(1): e2012074, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23205262

RESUMO

Follicular lymphoma (FL) remains incurable despite advances in new strategies of treatment, including monoclonal antibodies (MoAb). Except for early stages, FL is characterized by responses to treatments and systematic relapses. The main objective in this disease is to achieve a better progression free survival (PFS) and to increase overall survival (OS), mainly in young patients. In order to improve the results of conventional chemotherapy, autologous stem cell transplant (ASCT) is a feasible treatment in these patients. In this moment, ASCT is not recommended as first line treatment, except for transformed FL, but is a good strategy as salvage therapy with an improved PFS and OS. New drugs have been introduced to enhance responses of ASCT, but nowadays they are not part of conventional conditioning regimen.

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