RESUMO
BACKGROUND: Pompe's disease is a metabolic myopathy caused by a deficiency of acid alpha glucosidase (GAA), an enzyme that degrades lysosomal glycogen. Late-onset Pompe's disease is characterized by progressive muscle weakness and loss of respiratory function, leading to early death. We conducted a randomized, placebo-controlled trial of alglucosidase alfa, a recombinant human GAA, for the treatment of late-onset Pompe's disease. METHODS: Ninety patients who were 8 years of age or older, ambulatory, and free of invasive ventilation were randomly assigned to receive biweekly intravenous alglucosidase alfa (20 mg per kilogram of body weight) or placebo for 78 weeks at eight centers in the United States and Europe. The two primary end points were distance walked during a 6-minute walk test and percentage of predicted forced vital capacity (FVC). RESULTS: At 78 weeks, the estimated mean changes from baseline in the primary end points favored alglucosidase alfa (an increase of 28.1+/-13.1 m on the 6-minute walk test and an absolute increase of 3.4+/-1.2 percentage points in FVC; P=0.03 and P=0.006, respectively). Similar proportions of patients in the two groups had adverse events, serious adverse events, and infusion-associated reactions; events that occurred only in patients who received the active study drug included anaphylactic reactions and infusion-associated reactions of urticaria, flushing, hyperhidrosis, chest discomfort, vomiting, and increased blood pressure (each of which occurred in 5 to 8% of the patients). CONCLUSIONS: In this study population, treatment with alglucosidase alfa was associated with improved walking distance and stabilization of pulmonary function over an 18-month period. (ClinicalTrials.gov number, NCT00158600.)
Assuntos
Doença de Depósito de Glicogênio Tipo II/tratamento farmacológico , alfa-Glucosidases/uso terapêutico , Adolescente , Adulto , Idade de Início , Idoso , Análise de Variância , Criança , Hipersensibilidade a Drogas/etiologia , Feminino , Doença de Depósito de Glicogênio Tipo II/fisiopatologia , Humanos , Imunoglobulina G/sangue , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Capacidade Vital/efeitos dos fármacos , Caminhada , Adulto Jovem , alfa-Glucosidases/efeitos adversos , alfa-Glucosidases/imunologiaRESUMO
OBJECTIVE: Retinoids are crucial in the regulation of fundamental cellular processes including terminal differentiation of both normal and malignant myeloid progenitors. The aim of this study was to identify and characterize retinoic acid (RA) target genes. METHODS AND RESULTS: RTP801 is a recently cloned stress response gene that acts as a negative regulator of the mTOR pathway. Here we identified RTP801 as a novel early RA target gene in myeloid cells. RTP801 mRNA levels are induced in acute myeloid leukemia (AML) cell lines during RA-dependent differentiation and are differentially expressed during maturation of normal CD34(+) cells. The myeloid-specific, differentiation-related transcription factor C/EBPepsilon also induces RTP801 expression. Overexpression of RTP801 in the U937 leukemic cells leads to growth inhibition and apoptosis. Conversely, silencing of endogenous RTP801 by shRNA reduces RA-induced differentiation of the U937 cells. Downregulation of RTP801 also abrogates hypoxia-induced inhibition of mTOR in those cells. CONCLUSION: Taken together, our data suggest that RTP801 is an important RA-regulated gene involved in myeloid differentiation, which could represent a therapeutic target in leukemia.
Assuntos
Diferenciação Celular/genética , Leucemia Mieloide/patologia , Fatores de Transcrição/genética , Doença Aguda , Apoptose , Divisão Celular , Granulócitos/citologia , Humanos , Leucemia Mieloide/genética , Fosforilação , Proteínas Quinases/metabolismo , RNA Mensageiro/genética , Serina-Treonina Quinases TOR , Células U937RESUMO
Drug-induced scleroderma is a rare adverse effect of some chemotherapeutic drugs, such as taxanes and bleomycin. Capecitabine, an oral fluoropyrimidine approved for the treatment of metastatic breast and colon cancer, commonly causes cutaneous side effects including the hand-and-foot syndrome (HFS). Scleroderma-like skin changes associated with HFS associated with capecitabine is rare. However, diffuse scleroderma has never before been reported. We report a case of capecitabine-induced diffuse/systemic scleroderma in an 86-year-old female treated with capecitabine for metastatic colorectal cancer. She developed progressive skin and visceral sclerosis involving the lungs. We discuss the association between chemotherapy and scleroderma. We believe this is the first case of diffuse/systemic capecitabine-induced scleroderma without the presence of HFS. Early diagnosis is essential as fibrosis might be prevented in early stages. The capecitabine should be discontinued as early as possible.
RESUMO
CCAAT-enhancer binding protein-epsilon (C/EBPepsilon) is a nuclear transcription factor implicated in the regulation of terminal myeloid differentiation. Using a yeast two-hybrid screen, potential interaction partners of C/EBPepsilon involved in myeloid development were identified. C/EBPepsilon was found to associate with other C/EBP family members, including C/EBPepsilon and CHOP as well as other proteins that are known to contain a leucine-zipper protein interaction motif including CREB2, LDOC1, E6TP1, and AF-17. In addition, C/EBPepsilon demonstrated the potential for interaction with proteins that do not possess a leucine-zipper motif, including proteins that may be involved in sumoylation (protein inhibitor of activated STAT1 [PIAS1] and ubiquitin-conjugating enzyme E2I). As expected, the association of C/EBPepsilon with other C/EBP family members depends on the presence of a functional leucine-zipper motif. Mapping studies of C/EBPepsilon with PIAS1 (as an example of a nonleucine-zipper-containing protein) showed that C/EBPepsilon interacts with the amino-terminal domain of PIAS1. The function of C/EBPepsilon interacting proteins was further investigated. Co-expression of C/EBPepsilon with C/EBPdelta resulted in potent transactivation in a lactoferrin reporter system. A gel mobility shift assay suggests that C/EBPepsilon, C/EBPalpha, and C/EBPdelta proteins can bind as heterodimers to a C/EBP consensus DNA-binding site. As CHOP is known to represent a transcriptional repressor, the functional interaction between C/EBPepsilon and CHOP was investigated. Co-expression of C/EBPepsilon and c-Myb with CHOP caused marked transcriptional repression of target reporter genes. Our results suggest heterodimeric partners of C/EBPepsilon modulate the function of C/EBPepsilon in mediating gene transcription during myelopoiesis.
Assuntos
Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Diferenciação Celular/fisiologia , Mielopoese/fisiologia , Proteínas Modificadoras Pequenas Relacionadas à Ubiquitina/metabolismo , Fatores de Transcrição/metabolismo , Enzimas de Conjugação de Ubiquitina/metabolismo , Proteínas Estimuladoras de Ligação a CCAAT/genética , Ensaio de Desvio de Mobilidade Eletroforética , Regulação da Expressão Gênica/genética , Regulação da Expressão Gênica/fisiologia , Genes Reporter/genética , Humanos , Células Jurkat , Lactoferrina/genética , Lactoferrina/metabolismo , Mielopoese/genética , Ligação Proteica/fisiologia , Proteínas Inibidoras de STAT Ativados , Estrutura Terciária de Proteína/genética , Estrutura Terciária de Proteína/fisiologia , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Proteínas Modificadoras Pequenas Relacionadas à Ubiquitina/genéticaRESUMO
PURPOSE: This phase Ib study evaluated the safety, pharmacokinetics, pharmacodynamics, and antitumor activity of AMG 102, a fully human monoclonal antibody against hepatocyte growth factor/scatter factor (HGF/SF), in combination with bevacizumab or motesanib in patients with advanced solid tumors. EXPERIMENTAL DESIGN: Patients with treatment-refractory advanced solid tumors were sequentially enrolled into four cohorts (3, 10, or 20 mg/kg AMG 102 plus 10 mg/kg bevacizumab i.v. every 2 weeks, or 3 mg/kg AMG 102 i.v. every 2 weeks plus 75 mg motesanib orally once daily). RESULTS: Fourteen patients were enrolled and received AMG 102. The combination of AMG 102 with bevacizumab (n = 12) seemed to have acceptable toxicity. The number of patients (n = 2) who received AMG 102 plus motesanib was insufficient to adequately assess safety. No dose-limiting toxicities were reported. Enrollment in the motesanib cohort was suspended because of reports of cholecystitis in other motesanib studies. Treatment-emergent adverse events among patients receiving AMG 102 plus bevacizumab were generally mild and included fatigue (75%), nausea (58%), constipation (42%), and peripheral edema (42%). No anti-AMG 102 antibodies were detected. Bevacizumab did not seem to affect AMG 102 pharmacokinetics. Circulating total HGF/SF increased from baseline throughout the study. Eight of 10 evaluable patients had reductions in tumor dimensions, and stable disease at > or =8, > or =16, and > or =24 weeks occurred in 9, 7, and 4 patients, respectively. Progression-free survival ranged from 7.9 to 121.9 weeks. CONCLUSIONS: AMG 102 in combination with bevacizumab was well tolerated. Further evaluation of AMG 102 in combination with antiangiogenic agents is warranted.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais/farmacocinética , Anticorpos Monoclonais Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Área Sob a Curva , Bevacizumab , Estudos de Coortes , Constipação Intestinal/induzido quimicamente , Relação Dose-Resposta a Droga , Fadiga/induzido quimicamente , Feminino , Fator de Crescimento de Hepatócito/sangue , Humanos , Indóis/administração & dosagem , Indóis/efeitos adversos , Indóis/farmacocinética , Masculino , Taxa de Depuração Metabólica , Pessoa de Meia-Idade , Náusea/induzido quimicamente , Estadiamento de Neoplasias , Neoplasias/patologia , Niacinamida/administração & dosagem , Niacinamida/efeitos adversos , Niacinamida/análogos & derivados , Niacinamida/farmacocinética , Oligonucleotídeos , Resultado do TratamentoRESUMO
Acute promyelocytic leukemia (APL) is associated with chromosomal translocations involving retinoic acid receptor alpha (RAR alpha) and its fusion partners including promyelocytic leukemia (PML) and promyelocytic leukemia zinc finger (PLZF). Using oligonucleotide arrays, we examined changes in global gene expression mediated by the ectopic expression of either PML/RAR alpha (retinoid-sensitive) or PLZF/RAR alpha (retinoid-resistant) in U937 cells. Of more than 5000 genes analyzed, 16 genes were commonly up-regulated, and 57 genes were down-regulated by both fusion proteins suggesting their role in the APL phenotype. In our APL model, for example, TNFAIP2, TNFR2, ELF4, RAR gamma, and HoxA1 were down-regulated by both fusion proteins in the absence of retinoic acid (RA). RA strongly up-regulated these genes in PML/RAR alpha, but not in PLZF/RAR alpha expressing U937 cells. Expression studies in NB4, retinoid-resistant NB4-R2, normal human CD34+ cells, and APL patient samples strongly suggest their role in the regulation of granulocytic differentiation. Furthermore, combined treatment with tumor necrosis factor alpha (TNF alpha) and RA synergistically enhanced granulocytic differentiation in NB4 cells but not in NB4-R2 cells. Our data indicate that APL pathogenesis and retinoid-induced granulocytic differentiation of APL cells involve genes in the cell death pathway, and that cooperation between the RA and TNFalpha signaling pathways exists. Targeting both the retinoid-dependent differentiation and the cell death pathways may improve leukemic therapy, especially in retinoid-resistant acute myeloid leukemia.
Assuntos
Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Proteínas de Neoplasias/fisiologia , Proteínas de Fusão Oncogênica/fisiologia , Tretinoína/farmacologia , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Resistencia a Medicamentos Antineoplásicos , Sinergismo Farmacológico , Granulócitos/patologia , Humanos , Leucemia Promielocítica Aguda/etiologia , Leucemia Promielocítica Aguda/genética , Leucemia Promielocítica Aguda/patologia , Análise de Sequência com Séries de Oligonucleotídeos , Fator de Necrose Tumoral alfa/farmacologia , Células U937RESUMO
The transcription factor C/EBPalpha plays a critical role in the process of granulocytic differentiation. Recently, mutations that abrogated transcriptional activation of C/EBPalpha were detected in acute myeloid leukemia patient samples. Moreover, the progression of chronic myelogenous leukemia (CML) to blast crisis in patients was correlated with down-modulation of C/EBPalpha. The KCL22 cell line, derived from BCR-ABL+ CML in blast crisis, expressed wild-type C/EBPepsilon protein but not a functional C/EBPalpha, -beta, and -gamma. Restoration of C/EBPalpha expression in KCL22 cells triggered a profound proliferative arrest, a block in the G2/M phase of the cell cycle and a gradual increase in apoptosis. Within 3 days of inducing expression of C/EBPalpha, a remarkable neutrophilic differentiation of the KCL22 blast cells occurred as shown by morphologic changes, induction of expression of CD11b, primary, secondary, and tertiary granule proteins, and granulocyte colony-stimulating factor receptor. Using high density oligonucleotide microarrays, the gene expression profile of KCL22 cells stably transfected with C/EBPalpha was compared with that of empty vector, and we identified genes not previously known to be regulated by C/EBPalpha. These included the up-regulation of those genes important for regulation of hematopoietic stem cell homing, granulocytic differentiation, and cell cycle, whereas down-regulation occurred for genes coding for signaling molecules and transcription factors that are implicated in regulation of proliferation and differentiation of hematopoietic cells. Our study showed that restoration of C/EBPalpha expression in BCR-ABL+ leukemic cells in blast crisis is sufficient for rapid neutrophil differentiation suggesting a potential therapeutic role for ectopic transfer of C/EBPalpha in acute phase of CML.
Assuntos
Proteína alfa Estimuladora de Ligação a CCAAT/biossíntese , Proteínas de Fusão bcr-abl/metabolismo , Apoptose , Northern Blotting , Western Blotting , Proteína alfa Estimuladora de Ligação a CCAAT/química , Antígeno CD11b/biossíntese , Diferenciação Celular , Linhagem Celular , Linhagem Celular Tumoral , Separação Celular , Regulação para Baixo , Citometria de Fluxo , Fase G2 , Regulação da Expressão Gênica , Vetores Genéticos , Granulócitos/citologia , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Microscopia de Fluorescência , Mitose , Mutação , Análise de Sequência com Séries de Oligonucleotídeos , Oligonucleotídeos/química , Plasmídeos/metabolismo , RNA/química , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Fatores de Tempo , Ativação Transcricional , Transfecção , Regulação para CimaRESUMO
Members of the CCAAT/enhancer-binding protein (C/EBP) family are involved in the regulation of cellular differentiation and function of many tissues. Unlike the other members of the family, C/EBP epsilon expression is restricted to granulocytes, macrophages, and lymphocytes. C/EBP epsilon is highly conserved between human and rodents and is essential for terminal granulopoiesis in both species. To study the role that C/EBP epsilon plays in macrophages, wild-type and C/EBP epsilon-deficient (-/-) murine macrophages obtained from thioglycollate-elicited peritoneal lavages and differentiated bone marrow cells were compared. Although macrophage development occurred in both types of mice, the C/EBP epsilon -/- cells had a lower expression of macrophage markers and a morphologic and ultrastructural appearance of immaturity. Phagocytic function, measured by calculating the percentage of internalized opsonized fluorescein isothiocyanate (FITC)-labeled yeast, was significantly impaired in the C/EBP epsilon -/- macrophages compared with their wild-type counterparts. Furthermore, the differential expression of 26 macrophage-specific genes between wild-type and C/EBP-/- mice was analyzed. A subset of genes involved in differentiation, immune, and inflammatory responses was found down-regulated in the C/EBP-/- macrophages. Taken together, this study implicates the C/EBP epsilon gene as an important transcription factor required for normal function and development of macrophages.
Assuntos
Proteínas Estimuladoras de Ligação a CCAAT/fisiologia , Citocinas/biossíntese , Macrófagos/fisiologia , Animais , Células da Medula Óssea/citologia , Proteínas Estimuladoras de Ligação a CCAAT/genética , Proteínas Estimuladoras de Ligação a CCAAT/farmacologia , Técnicas de Cultura de Células/métodos , Diferenciação Celular/efeitos dos fármacos , Citocinas/efeitos dos fármacos , Perfilação da Expressão Gênica , Humanos , Macrófagos/citologia , Macrófagos/metabolismo , Macrófagos Peritoneais/metabolismo , Macrófagos Peritoneais/fisiologia , Camundongos , Camundongos Knockout , Fagocitose/efeitos dos fármacos , TioglicolatosRESUMO
Retinoic acid (RA) promotes granulocytic differentiation of normal hematopoietic cells and acute promyelocytic leukemia (APL) blasts by transcriptional modulation of myeloid regulatory genes. In this study, we have identified the C/EBP homologous protein (CHOP) as a novel retinoid-responsive gene using a polymerase chain reaction (PCR)-based cDNA subtraction method. All-trans retinoic acid (ATRA) induced a biphasic expression of CHOP mRNA in the NB4 and HL60 AML cell lines. Levels of CHOP expression increased within 1 hour of exposure to ATRA. ATRA expression became nearly absent between 6 and 24 hours, and a second phase of induction occurred after 48 hours. Retinoid-dependent regulation of CHOP expression was also observed in normal human neutrophils but not in peripheral blood mononuclear cells. In addition, retinoid-dependent regulation of CHOP expression was not observed in retinoid-nonresponsive cell lines HL60R and NB4-R2. CHOP expression was regulated at the transcriptional level and was independent of new protein synthesis. CHOP heterodimerized with C/EBPepsilon and negatively regulated the myeloid-specific gene lactoferrin. Furthermore, CHOP transcriptionally inhibited C/EBPalpha- and C/EBPepsilon-dependent induction of secondary granule gene expression. RA signaling in granulocytic differentiation involves regulated expression of CHOP and C/EBPepsilon in a coordinated fashion.
Assuntos
Proteínas Estimuladoras de Ligação a CCAAT/genética , Regulação Neoplásica da Expressão Gênica/genética , Fatores de Transcrição/genética , Tretinoína/farmacologia , Dano ao DNA , DNA Complementar/genética , Células HL-60 , Humanos , Reação em Cadeia da Polimerase/métodos , RNA Mensageiro/genética , Fator de Transcrição CHOPRESUMO
CCAAT/enhancer binding proteins (C/EBPs) are a family of factors that regulate cell growth and differentiation. These factors, particularly C/EBPalpha and C/EBPepsilon, have important roles in normal myelopoiesis. In addition, loss of C/EBP activity appears to have a role in the pathogenesis of myeloid disorders including acute myeloid leukemia (AML). Acute promyelocytic leukemia (APL) is a subtype of AML in which a role for C/EBPs has been postulated. In almost all cases of APL, a promyelocytic leukemia-retinoic acid receptor alpha (PML-RARalpha) fusion protein is expressed as a result of a t(15;17)(q22;q12) chromosomal translocation. PML-RARalpha inhibits expression of C/EBPepsilon, whereas all-trans retinoic acid (tRA), a differentiating agent to which APL is particularly susceptible, induces C/EBPepsilon expression. PML-RARalpha may also inhibit C/EBPalpha activity. Thus, the effects of PML-RARalpha on C/EBPs may contribute to both the development of leukemia and the unique sensitivity of APL to tRA. We tested the hypothesis that increasing the activity of C/EBPs would revert the leukemic phenotype. C/EBPalpha and C/EBPepsilon were introduced into the FDC-P1 myeloid cell line and into leukemic cells from PML-RARA transgenic mice. C/EBP factors suppressed growth and induced partial differentiation in vitro. In vivo, enhanced expression of C/EBPs prolonged survival. By using a tamoxifen-responsive version of C/EBPepsilon, we observed that C/EBPepsilon could mimic the effect of tRA, driving neutrophilic differentiation in leukemic animals. Our results support the hypothesis that induction of C/EBP activity is a critical effect of tRA in APL. Furthermore, our findings suggest that targeted modulation of C/EBP activities could provide a new approach to therapy of AML.