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1.
Neuropathol Appl Neurobiol ; 44(4): 427-438, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-28543916

RESUMO

AIMS: Peripheral neuropathy (PN), the major neurological complication of chronic HCV infection, is frequently associated with mixed cryoglobulinaemia (MC) and small-vessel systemic vasculitis. While humoral and cell-mediated immune mechanisms are suspected to act together in an aberrant immune response that results in peripheral nerve damage, the role of HCV remains largely speculative. The possible demonstration of HCV in peripheral nerve tissue would obviously assume important pathogenic implications. METHODS: We studied sural nerve biopsies from 11 HCV-positive patients with neuropathic symptoms: five with and six without MC. In situ hybridization (ISH) and immunofluorescence studies were carried out to detect genomic and antigenomic HCV RNA sequences and HCV-encoded E2-glycoprotein, respectively. RESULTS: Epineurial vascular deposits of E2-glycoprotein were found in four (80%) MC and in two (33.3%) non-MC patients, respectively. These findings were enhanced by the perivascular deposition of positive-, though not negative-strand replicative RNA, as also found in the nerve extracts of all patients. Mild inflammatory cell infiltrates with no deposits of immunoglobulins and/or complement proteins were revealed around small vessels, without distinct vasculitis changes between MC and non-MC patients. CONCLUSIONS: These results indicate that nerve vascular HCV RNA/E2 deposits associated to perivascular inflammatory infiltrates were similar in chronically HCV-infected patients, regardless of cryoglobulin occurrence. Given the failure to demonstrate HCV productive infection in the examined sural nerve biopsies, nerve damage is likely to result from virus-triggered immune-mediated mechanisms.


Assuntos
Hepacivirus/isolamento & purificação , Hepatite C/virologia , Doenças do Sistema Nervoso Periférico/virologia , Nervo Sural/virologia , Proteínas do Envelope Viral/metabolismo , Idoso , Sequência de Bases , Biópsia , Feminino , Hepatite C/metabolismo , Hepatite C/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Doenças do Sistema Nervoso Periférico/metabolismo , Doenças do Sistema Nervoso Periférico/patologia , Nervo Sural/metabolismo , Nervo Sural/patologia
2.
Lupus ; 27(12): 1926-1935, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30180771

RESUMO

Belimumab, a specific inhibitor of the soluble B lymphocyte stimulator (BlyS), is the first biological drug approved by the United States Food and Drug Administration for the treatment of patients with active systemic lupus erythematosus (SLE) refractory to standard therapy. Given that an imbalance between regulatory T cells (Treg) and interleukin (IL)-17A-secreting T cells (Th17) has been reported in various autoimmune disorders, we assessed the frequency of both Treg and Th17 peripheral blood populations before and after belimumab administration in 20 patients with active SLE refractory to standard therapy. After six months of treatment, the mean SELENA-SLEDAI score as well as the mean anti-double-stranded DNA antibody titers were significantly decreased. In addition, we observed a significant increase in Treg percentages and a parallel, significant decrease in Th17 percentages, accompanied by significantly reduced serum levels of IL-21. In vitro studies showed that Treg purified from belimumab-treated patients were fully functional and displayed a suppressor function similar to that of Treg purified from healthy donors. Belimumab can restore Treg/Th17 balance in SLE patients with uncontrolled disease activity, and this results in decreased flare rate and reduced glucocorticoid dosage.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Fator Ativador de Células B/antagonistas & inibidores , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Linfócitos T Reguladores/efeitos dos fármacos , Células Th17/efeitos dos fármacos , Adulto , Anticorpos Antinucleares/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Linfócitos T Reguladores/imunologia , Células Th17/imunologia , Resultado do Tratamento
3.
Clin Exp Immunol ; 182(3): 323-31, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26219420

RESUMO

Immunoglobulin variable region heavy chain (IgVH ) somatic gene diversification is instrumental in the transformation process that characterizes hepatitis C virus (HCV)-related B cell lymphoproliferative disorders. However, the extent to which activation-induced cytidine deaminase (AID), an enzyme essential for IgV gene somatic hypermutation (SHM), is active in cryoglobulinaemic vasculitis (CV) remains unclear. AID mRNA expression in the peripheral blood of 102 chronically hepatitis C virus (HCV)-infected patients (58 with and 44 without CV) and 26 healthy subjects was investigated using real-time reverse transcription-polymerase chain reaction (RT-PCR). The features of activation-induced cytidine deaminase (AID) protein and mRNA transcripts were explored in liver tissue biopsies and portal tracts isolated using laser capture microdissection. In chronically HCV-infected patients, AID mRNA expression was almost threefold higher in those with than in those without CV and sevenfold higher than in healthy subjects (median-fold: 6.68 versus 2.54, P = 0.03 and versus 0.95, P = 0.0003). AID transcript levels were significantly higher in polyclonal than in clonally restricted B cell preparations in either CV or non-CV patients (median-fold, 15.0 versus 2.70, P = 0.009 and 3.46 versus 1.58, P = 0.02, respectively). AID gene expression was found to be related negatively to age and virological parameters. AID protein was found in portal tracts containing inflammatory cells that, in several instances, expressed AID mRNA transcripts. Our data indicate that the aberrant expression of AID may reflect continuous B cell activation and sustained survival signals in HCV-related CV patients.


Assuntos
Linfócitos B , Crioglobulinemia , Citidina Desaminase , Hepacivirus/imunologia , Hepatite C Crônica , Vasculite , Fatores Etários , Idoso , Linfócitos B/enzimologia , Linfócitos B/imunologia , Linfócitos B/patologia , Sobrevivência Celular/imunologia , Crioglobulinemia/complicações , Crioglobulinemia/enzimologia , Crioglobulinemia/imunologia , Crioglobulinemia/patologia , Citidina Desaminase/biossíntese , Citidina Desaminase/imunologia , Feminino , Regulação Enzimológica da Expressão Gênica/imunologia , Hepatite C Crônica/complicações , Hepatite C Crônica/enzimologia , Hepatite C Crônica/imunologia , Hepatite C Crônica/patologia , Humanos , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Transdução de Sinais/imunologia , Vasculite/complicações , Vasculite/enzimologia , Vasculite/imunologia , Vasculite/patologia
4.
Int J Immunopathol Pharmacol ; 24(1): 195-200, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21496403

RESUMO

Common drugs in the therapy of chronic idiopathic urticaria (CIU) include antihistamines alone or combined with corticosteroids, but severe unresponsive patients require alternative treatments. This retrospective study aims to evaluate clinical response and safety of low-dose and long-term oral Cyclosporin-A (CyA) in unresponsive patients. One hundred and ten CIU patients, unresponsive to a previous treatment (antihistamines plus prednisone 0.2 mg/kg/day), received additional oral CyA 1–3 mg/kg/day for 6 months. The patients were subdivided into three groups (A, B, C) according to the different CyA doses. Parameters of clinical efficacy including pruritus, and size and number of wheals were evaluated at baseline, after three and six months. All adverse events were recorded. The mean total symptom severity score decreased by 63% in Group A, 76% in Group B, and 85% in Group C after 6 months. Total disappearance of the symptoms was recorded in 43 patients (39.1%): 7 (28%) of Group A; 12 (37.5%) of Group B and 24 (45%) of Group C. After a mean of 2 months from CyA suspension, 14 patients (11%) had recurrence of symptoms. Minor side effects were noted in 8 patients (7%). Our study indicates that low-dose, long-term CyA therapy is efficacious and safe in severe unresponsive CIU.


Assuntos
Ciclosporina/uso terapêutico , Urticária/tratamento farmacológico , Adulto , Idoso , Doença Crônica , Ciclosporina/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
5.
J Exp Med ; 184(6): 2287-300, 1996 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-8976184

RESUMO

Previous studies have demonstrated that T cell-reactive antibodies in HIV-1 infection contribute to lymphocyte depletion by cytotoxicity that involves differential membrane targets, such as the 43.5-kD receptor on CEM cells. Here, we show that these antibodies bind Fas as result of a molecular mimicry of the gp120. Both flow cytometry and immunoblotting using the human Fas-transfected mouse WC8 lymphoma revealed positive binding of immunoglobulin G from several patients to a 43.8-kD membrane receptor that also reacts with the CH11 anti-Fas monoclonal antibody. Specificity to Fas was further confirmed to chimeric recombinant human Fas-Fc by ELISA, whereas overlapping peptide mapping of a Fas domain (VEINCTR-N) shared by gp120 V3 loop demonstrated a predominant affinity to the full-length 10-mer peptide. Four anti-Fas affinity preparations greatly increased the subdiploid DNA peak of CEM cells similar to agonist ligands of Fas. In addition, anti-Fas immunoglobulin G strongly inhibited the [3H]thymidine uptake of CEM cells in proliferative assays, inducing a suppression as high as provoked by both CH11 mAb and recombinant human Fas ligand. Since anti-Fas were reactive to gp120, it is conceivable that antibodies binding that domain within the V3 region are effective cross-linkers of Fas and increase apoptosis in peripheral T cells. These results suggest that autologous stimulation of the Fas pathway, rather than of lymphocytotoxic antibodies, may aggravate lymphopenia in a number of HIV-1+ subjects.


Assuntos
Síndrome da Imunodeficiência Adquirida/imunologia , Anticorpos Anti-HIV/imunologia , Proteína gp120 do Envelope de HIV/química , Proteína gp120 do Envelope de HIV/imunologia , HIV-1/imunologia , Estrutura Secundária de Proteína , Linfócitos T/imunologia , Receptor fas/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais , Apoptose , Sítios de Ligação de Anticorpos , Linhagem Celular , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Linfoma , Camundongos , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/imunologia , Proteínas Recombinantes/química , Proteínas Recombinantes/imunologia , Transfecção , Receptor fas/química
6.
J Intern Med ; 267(3): 260-77, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20201920

RESUMO

The B lymphocyte-associated antigen CD20 is becoming an important immunotherapy target for autoimmune diseases, although its biological function has not been defined. Besides rheumatoid arthritis, growing experience with B cell-depleting therapy indicates that it may be effective in Sjögren's syndrome, dermatomyositis-polymyositis, systemic lupus erythematosus and some types of vasculitides. However, controlled clinical trials are still lacking for some of these indications. Infection has not been seen as a major limitation to this therapy, but reports of progressive multifocal leukoencephalopathy in an extremely small number of patients are of concern. Here, we review the therapeutic actions of anti-CD20 antibodies, and the recent and ongoing clinical trials with CD20-depleting therapy in autoimmune diseases.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Antígenos CD20/imunologia , Doenças Autoimunes/tratamento farmacológico , Linfócitos B/imunologia , Fatores Imunológicos/uso terapêutico , Animais , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais Murinos , Doenças Autoimunes/imunologia , Humanos , Fatores Imunológicos/efeitos adversos , Fatores Imunológicos/imunologia , Camundongos , Ensaios Clínicos Controlados Aleatórios como Assunto , Rituximab
7.
G Ital Nefrol ; 26(2): 161-70, 2009.
Artigo em Italiano | MEDLINE | ID: mdl-19382072

RESUMO

Biosimilars are medicinal products proposed as copies of biotech drugs whose patents have expired. Their entry into the therapeutic armamentarium entails knowledge of the rules established in Europe relevant to their use in clinical practice. In September 2007, an Italian panel of experts comprising two nephrologists, a clinical immunologist, an oncohematologist, a pharmacologist, and a hospital pharmacist examined the main features of biotech drugs and the issues faced by the regulatory authorities in the definition of a specific approval pathway for biosimilars in Europe. The panel of experts agreed that it is important to inform the medical and scientific community that biosimilars are not exact copies of their reference products; therefore the rules governing their clinical use are not the same as those established for biotech drugs in general. Patient safety should be the fundamental principle guiding therapeutic choices, and making these choices should be the prerogative of physicians.


Assuntos
Produtos Biológicos/normas , Segurança , Humanos
8.
Curr Med Chem ; 15(2): 117-26, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18220767

RESUMO

Recognition of hepatitis C virus (HCV) as an etiological factor in mixed cryoglobulinemia (MC) has dramatically changed our point of view in its treatment. Emphasis is placed on abatement and clearance of viral load and deletion of clonal expansions of IgM molecules with rheumatoid factor activity-synthesising B cells. The purpose of this review is to discuss the underlying scientific rationale and results of clinical studies of new treatment approaches to MC, with a focus on cell-depleting therapies and chemokine blockade. Additional antiviral agents directed to several phases of HCV life cycle acting with different or alternate mechanisms are proposed with the goal to enhance response rates more broadly suitable for MC patients with vasculitis and peripheral neuropathies. The majority of the available data on these new treatment approaches stems from open-label studies, but controlled trials are under way. Therapy directed against chemokines and/or cytokines represents an interesting and promising future target.


Assuntos
Crioglobulinemia/tratamento farmacológico , Crioglobulinemia/virologia , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/tratamento farmacológico , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Murinos , Antivirais/uso terapêutico , Linfócitos B/citologia , Linfócitos B/imunologia , Linfócitos B/metabolismo , Crioglobulinemia/etiologia , Crioglobulinemia/genética , Inibidores Enzimáticos/uso terapêutico , Hepacivirus/metabolismo , Hepatite C Crônica/virologia , Humanos , Imunoglobulina M/metabolismo , Interferons/uso terapêutico , Oligonucleotídeos Antissenso/uso terapêutico , Fator Reumatoide/metabolismo , Ribavirina/uso terapêutico , Rituximab , Transdução de Sinais
9.
Clin Exp Immunol ; 154(2): 247-54, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18795942

RESUMO

Imbalance of cytokine homeostasis is a prominent feature of both experimental and human systemic lupus erythematosus (SLE). Because interleukin (IL)-12 promotes interferon (IFN)-gamma production leading to polarization of peripheral cells toward a T helper (Th) 1 phenotype, we investigated its role in lupus nephritis (LN). Soluble Th1 and Th2 cytokines were measured by enzyme-linked immunosorbent assay (ELISA) in sera and urines of SLE patients and controls. Th1/Th2 peripheral lymphocyte polarization was determined by flow cytometry. Glomerular accumulation of IL-12 was evaluated by immunohistochemistry, whereas urinary IL-12 was evaluated by ELISA. Higher serum IL-12 levels in SLE were associated with LN, whereas IL-4 was unrelated to the renal damage. Peripheral cells from LN patients showed a Th1 phenotype with a high IFN-gamma expression that paralleled the severity of renal damage. IL-12 was present within glomerular mononuclear cells in classes IV and V LN, and its accumulation was correlated strongly with urinary levels. IL-12 overexpression in SLE may contribute to the development of LN. Both serum and urinary IL-12 elevation reflect its glomerular production and parallel Th1 polarization of peripheral T cells and high IFN-gamma production. In SLE patients, IL-12 measurement may thus be predictive of the development of LN.


Assuntos
Interleucina-12/metabolismo , Nefrite Lúpica/imunologia , Células Th1/imunologia , Adulto , Biomarcadores/urina , Células Cultivadas , Feminino , Humanos , Imunofenotipagem , Interferon gama/sangue , Interleucina-12/sangue , Interleucina-12/urina , Interleucina-4/sangue , Glomérulos Renais/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Regulação para Cima/imunologia
10.
Eur J Clin Invest ; 38(12): 966-8, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19021723

RESUMO

We report a strikingly positive, late response to bortezomib in conjunction with pegylated liposomal doxorubicin in a 79-year old woman with multiple myeloma (MM). The patient obtained a partial remission after eight courses of therapy and a complete remission about 10 months after the end of therapy. This delayed complete remission may be similar to the spontaneous regression reported for other malignancies such as melanoma or lymphoma. We postulate that the immune response and a persistent anti-angiogenic effect of bortezomib could well explain the delayed complete remission in our patient.


Assuntos
Ácidos Borônicos/administração & dosagem , Doxorrubicina/análogos & derivados , Mieloma Múltiplo/tratamento farmacológico , Polietilenoglicóis/administração & dosagem , Pirazinas/administração & dosagem , Indução de Remissão , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica , Bortezomib , Doxorrubicina/administração & dosagem , Feminino , Humanos , Fatores de Tempo
11.
J Clin Apher ; 23(3): 118-22, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18484642

RESUMO

Hepatitis C virus (HCV) is the major cause of cryoglobulinemia. Skin lesions are frequent and can be cured from the removal of cryoglobulins by therapeutic apheresis. We describe a case of HCV-positive type I cryoglobulinemia with severe leg ulcers, not responsive to antiviral and immunosuppressive treatment. Thirty sessions of double filtration plasmapheresis were performed, over a period of 6 months, with no other associated treatment. Before and after each session an assessment of immunoglobulins, complement, cryocrit, and fibrinogen was made. HCV RNA levels were determined in serum cryoprecipitate, supernatant before and after each session, and in the collection bag. No differences in pre and postapheresis values were observed in the serum concentrations and the supernatant, whereas the postapheresis cryoprecipitate showed a significantly reduced viral load (P < 0.02) as compared with the preapheresis values. There was improvement in the condition of ulcers in the leg during apheresis and had completely regressed by the end of the cycle.


Assuntos
Crioglobulinemia/terapia , Úlcera da Perna/terapia , Plasmaferese/métodos , Adulto , Crioglobulinemia/sangue , Crioglobulinemia/complicações , Hepacivirus , Hepatite C/sangue , Hepatite C/complicações , Hepatite C/terapia , Anticorpos Anti-Hepatite C/sangue , Humanos , Úlcera da Perna/sangue , Úlcera da Perna/etiologia , Masculino , RNA Viral/sangue
12.
Leukemia ; 20(6): 1145-54, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16617326

RESUMO

We demonstrate that in three cases of MC (two with immunocytoma), the IgM-RF+ component of their cryoprecipitated represents the circulating counterpart of the B-cell receptor (BCR) of the monoclonal overexpanded B-cell population. These IgMs were isolated and used to demonstrate a crossreactivity against both hepatitis C virus (HCV) NS3 antigen and the Fc portion of IgG. Epitopes were identified in a fraction of exemplary samples by using epitope excision approach (NS(31250-1334) and IgG Fc(345-355)). The same phenomenon of crossreactivity has been shown to occur in vivo after immunization of a mouse with the NS3(1251-1270) peptide. To verify if the same reaction was also present in MC samples characterized by an oligo/polyclonal B-cell proliferation, IgM crossreactivity was tested in 14 additional samples. Five out of the 14 were reactive against HCV NS3 and 11 out of 14 were reactive against IgG-Fc peptide. The data support the role of HCV NS3 antigen in a subset of patients with MC, whereas the high frequency of the IgG-Fc epitope suggests that these B cells originate from precursors strongly selected for auto-IgG specificity. We suggest that engagement of specific BCRs by NS3 (or NS3-immunocomplex) antigen could explain the prevalence of IgM cryoglobulins in these patients.


Assuntos
Crioglobulinemia/classificação , Crioglobulinemia/imunologia , Fragmentos Fc das Imunoglobulinas/imunologia , Imunoglobulina M/imunologia , Linfoma de Células B/imunologia , Proteínas não Estruturais Virais/imunologia , Células Clonais , Crioglobulinemia/diagnóstico , Epitopos/imunologia , Humanos , Imunoglobulina M/efeitos dos fármacos , Modelos Moleculares , Fragmentos de Peptídeos/imunologia , Ligação Proteica , Conformação Proteica , Estrutura Secundária de Proteína , Receptores de Antígenos de Linfócitos B/imunologia , Fator Reumatoide/efeitos dos fármacos , Fator Reumatoide/imunologia , Proteínas não Estruturais Virais/farmacologia
13.
Clin Exp Med ; 7(3): 83-97, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17972050

RESUMO

The melphalan-prednisone regimen has been considered as standard therapy for patients with multiple myeloma (MM) for many years. Recently, high-dose chemotherapy with stem-cell support has extended progression-free survival and increased overall survival, and it is now considered conventional therapy in younger patients. However, most patients relapse and the salvage treatment is not very effective. New active drugs, including immunomodulatory agents, thalidomide (Thal) and lenalidomide, and the proteasome inhibitor bortezomib, have shown promising anti-myeloma activity. These novel treatments are aimed at overcoming resistance of tumour cells to conventional chemotherapy, acting both directly on myeloma cells and indirectly by blocking the interactions of myeloma cells with their local microenvironment and suppressing growth and survival signals induced by autocrine and paracrine loops in the bone marrow. Thal has been widely studied, mostly in combination regimens in patients with relapsed MM and, more recently, in front-line therapy, showing efficacy in terms of response rate and event-free survival. Bortezomib has been found to possess remarkable activity, especially in combination with other chemotherapeutic agents, in relapsed/refractory and newly diagnosed MM, as well as in patients presenting adverse prognostic factors. Lenalidomide, in combination with dexamethasone, is showing high overall response rates in relapsed and refractory MM and promising results also in first-line therapy. In this paper, the results of the most significant trials with Thal, bortezomib and lenalidomide are reported. Several ongoing clinical studies will hopefully allow the identification of the most active combinations capable of improving survival in patients with MM.


Assuntos
Antineoplásicos/uso terapêutico , Ácidos Borônicos/uso terapêutico , Mieloma Múltiplo/tratamento farmacológico , Pirazinas/uso terapêutico , Talidomida/análogos & derivados , Talidomida/uso terapêutico , Bortezomib , Ensaios Clínicos como Assunto , Humanos , Lenalidomida
14.
Leukemia ; 30(3): 640-8, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26487273

RESUMO

Bortezomib (bort) has improved overall survival in patients with multiple myeloma (MM), but the majority of them develop drug resistance. In this study, we demonstrate that bone marrow (BM) fibroblasts (cancer-associated fibroblasts; CAFs) from bort-resistant patients are insensitive to bort and protect the RPMI8226 and patients' plasma cells against bort-induced apoptosis. Bort triggers CAFs to produce high levels of interleukin (IL)-6, IL-8, insulin-like growth factor (IGF)-1 and transforming growth factor (TGF) ß. Proteomic studies on CAFs demonstrate that bort resistance parallels activation of oxidative stress and pro-survival autophagy. Indeed, bort induces reactive oxygen species in bort-resistant CAFs and activates autophagy by increasing light chain 3 protein (LC3)-II and inhibiting p62 and phospho-mammalian target of rapamycin. The small-interfering RNA knockdown of Atg7, and treatment with 3-methyladenine, restores bort sensitivity in bort-resistant CAFs and produces cytotoxicity in plasma cells co-cultured with CAFs. In the syngeneic 5T33 MM model, bort-treatment induces the expansion of LC3-II(+) CAFs. TGFß mediates bort-induced autophagy, and its blockade by LY2109761, a selective TßRI/II inhibitor, reduces the expression of p-Smad2/3 and LC3-II and induces apoptosis in bort-resistant CAFs. A combination of bort and LY2109761 synergistically induces apoptosis of RPMI8226 co-cultured with bort-resistant CAFs. These data define a key role for CAFs in bort resistance of plasma cells and provide the basis for a novel targeted therapeutic approach.


Assuntos
Antineoplásicos/farmacologia , Bortezomib/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Mieloma Múltiplo/tratamento farmacológico , Pirazóis/farmacologia , Pirróis/farmacologia , Fator de Crescimento Transformador beta/antagonistas & inibidores , Idoso , Idoso de 80 Anos ou mais , Animais , Autofagia/efeitos dos fármacos , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/metabolismo , Células da Medula Óssea/patologia , Combinação de Medicamentos , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/patologia , Humanos , Masculino , Camundongos , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Pessoa de Meia-Idade , Mieloma Múltiplo/genética , Mieloma Múltiplo/mortalidade , Mieloma Múltiplo/patologia , Plasmócitos/efeitos dos fármacos , Plasmócitos/metabolismo , Plasmócitos/patologia , Cultura Primária de Células , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Transdução de Sinais , Análise de Sobrevida , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
15.
J Clin Oncol ; 9(3): 444-8, 1991 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1999714

RESUMO

The efficacy of alternating vincristine, melphalan (M), cyclophosphamide, prednisone/vincristine, carmustine, doxorubicin, and prednisone (VMCP/VBAP) polychemotherapy was compared with the M and prednisone (MP) regimen as induction treatment in multiple myeloma (MM). Three hundred four MM patients entered this study between March 1983 and July 1986; the analysis was performed in December 1989. The treatment groups did not show significant differences with respect to major prognostic factors. Median overall survival was 33.8 months. In the VMCP/VBAP and MP arms, after 12 induction chemotherapy cycles, 59.0% and 47.3% (P less than .068) of the patients achieved an M component reduction greater than 50%. No significant difference was observed in the two treatment arms in terms of remission duration (21.3 v 19.6 months, P less than .66) and survival (31.6 v 37.0 months, P less than .28). Patients younger than 65 years did not show any advantage from the alternating polychemotherapy. At diagnosis, the plasma cell labeling index (LI) and serum beta-2 microglobulin (beta 2-m) were evaluated in 173 and 183 patients, respectively. A significantly reduced survival was observed for patients with LI greater than or equal to 2% (16.4 months) or beta 2-m greater than or equal to 6 mg/L (20.4 months). Even in these poor-risk subgroups, VMCP/VBAP was not superior to MP.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Mieloma Múltiplo/tratamento farmacológico , Idoso , Carmustina/administração & dosagem , Ciclofosfamida/administração & dosagem , Doxorrubicina/administração & dosagem , Esquema de Medicação , Feminino , Humanos , Masculino , Melfalan/administração & dosagem , Pessoa de Meia-Idade , Mieloma Múltiplo/mortalidade , Mieloma Múltiplo/patologia , Prednisona/administração & dosagem , Prognóstico , Vincristina/administração & dosagem , Microglobulina beta-2/isolamento & purificação
16.
Mech Dev ; 100(2): 157-63, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11165474

RESUMO

It is generally accepted that vasculogenesis is limited to early embryogenesis and is believed not to occur in adult, whereas angiogenesis occurs in both the developing embryo and postnatal life. However, the distinction between them is not absolute, because both require endothelial cell proliferation and migration and three-dimensional reorganization of newly formed blood vessels, nor are they mutually exclusive, inasmuch as angioblasts can be incorporated into expanding pre-existing blood vessels. Recent observations indicate that vasculogenesis may not be restricted to early embryogenesis, but may also have a physiological role or contribute to the pathology of vascular diseases in adults. The major evidence in favor of this new view comes from: (i) demonstration of the presence of circulating endothelial cells and endothelial precursor cells; (ii) newly described mechanisms of blood vessel formation in tumor growth. The potential biomedical applications of endothelial precursor cells and the new opportunities for the development of new forms of tumor-targeted treatments are discussed.


Assuntos
Vasos Sanguíneos/embriologia , Neovascularização Fisiológica , Animais , Divisão Celular , Movimento Celular , Endotélio Vascular/embriologia , Humanos , Modelos Biológicos , Neovascularização Patológica
17.
Leukemia ; 18(6): 1054-8, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15057248

RESUMO

Extensive studies have identified reliable markers of lymphatic endothelial cells, and mechanisms and molecules that regulate development and growth of the lymphatic vessels. Vascular endothelial growth factors (VEGF)-C and VEGF-D, and their cognate receptor tyrosine kinase, VEGF receptor-3 (VEGFR-3), are critical regulators of lymphangiogenesis. By binding to its endothelial cell surface receptors VEGFR-1 and VEGFR-2, VEGF-A mediates vascular leakage, endothelial proliferation and migration. Angiopoietin-2 (Ang-2) is expressed at sites of blood vessel remodeling and invasion, and factors that induce angiogenesis in vivo, such as VEGF-A, upregulate Ang-2 in endothelial cells. In this review, we summarize the literature concerning the crosstalk between angiogenesis and lymphangiogenesis in tumor progression, that is, involvement of VEGF-C, VEGF-D and VEGFR-3 in angiogenesis, and the role played by VEGF-A and Ang-2 in lymphangiogenesis, respectively.


Assuntos
Linfangiogênese/fisiologia , Metástase Linfática/fisiopatologia , Neovascularização Patológica/fisiopatologia , Fatores de Crescimento do Endotélio Vascular/fisiologia , Humanos , Neovascularização Patológica/patologia
18.
Leukemia ; 17(10): 1961-6, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14513045
19.
Leukemia ; 16(9): 1680-4, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12200681

RESUMO

Bone marrow samples from 30 patients with myelodysplastic syndromes (MDS) grouped according to the International Prognostic Scoring System for MDS were investigated for counts of microvessels, total metachromatic mast cells (MC) and MC expressing tryptase, an angiogenesis-inducing molecule. Counts were higher in patients with a poor prognosis. The observation of a high correlation between microvessel counts and both total metachromatic and tryptase-reactive MC in all samples suggests that angiogenesis in MDS increases with their progression and that MC may intervene in the angiogenic response in MDS through tryptase contained in their secretory granules.


Assuntos
Medula Óssea/irrigação sanguínea , Mastócitos/enzimologia , Síndromes Mielodisplásicas/patologia , Neovascularização Patológica/patologia , Serina Endopeptidases/metabolismo , Antígenos CD34/análise , Medula Óssea/patologia , Progressão da Doença , Humanos , Técnicas Imunoenzimáticas , Microcirculação/química , Microcirculação/patologia , Síndromes Mielodisplásicas/enzimologia , Triptases
20.
Clin Exp Med ; 5(4): 141-60, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16362794

RESUMO

Most autoimmune diseases (ADs) are still associated with high morbidity and mortality despite the use of a wide range of drugs that can delay their progression, control their symptoms, but never bring about a complete cure. This failure has aroused interest in new forms of monoclonal antibody-based experimental immunotherapy (IT), aiming at targeting cellular antigens or cytokines involved in the pathogenesis of ADs. The first part of this review offers a general overview of the molecular mechanisms that mediate the immune response and the molecule regarded as potential IT targets. A critical evaluation will then be made of some forms of IT, with particular emphasis on TNF-alpha and CD20-blocking reagents. Lastly an account will be given of active IT whereby an endogenous response against antigens regarded as the target of passive IT can be induced by anti-idiotype or peptides.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Doenças Autoimunes/tratamento farmacológico , Anticorpos Monoclonais/efeitos adversos , Humanos
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