RESUMEN
PURPOSE: In our clinic, patients with occult breast lesions are treated with a sentinel node biopsy combined with wire-guided tumour excision. The aim of this retrospective study was to determine the influence of the sequence of wire localisation and sentinel node procedure on visualisation of the sentinel node. METHODS: A total of 136 patients had a wire-guided tumour excision combined with a sentinel node procedure. Sixty-six patients had guide wire localisation prior to the sentinel node procedure. Seventy patients had sentinel node visualisation before insertion of the guide wire. RESULTS: The sentinel node was visualised in 41 (62%) of the patients who first underwent guide wire localisation. In the group of patients who underwent visualisation of the sentinel node before placement of the guide wire, the sentinel node was visualised in 62 (89%). This is a significant difference in visualisation (p<0.001). CONCLUSION: This study shows that guide wire localisation prior to the sentinel node procedure negatively influences visualisation of the sentinel node.
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Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/patología , Aumento de la Imagen/instrumentación , Ganglios Linfáticos/diagnóstico por imagen , Ganglios Linfáticos/patología , Biopsia del Ganglio Linfático Centinela/instrumentación , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/cirugía , Femenino , Humanos , Aumento de la Imagen/métodos , Ganglios Linfáticos/cirugía , Metástasis Linfática , Persona de Mediana Edad , Cintigrafía , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Biopsia del Ganglio Linfático Centinela/métodosRESUMEN
OBJECTIVE: To compare survival of patients with disseminated aggressive non-Hodgkin's lymphoma (NHL) who were treated either as part of a clinical trial or in routine clinical practice. DESIGN: Retrospective. METHOD: The survival was studied of patients with disseminated NHL of an intermediate or high degree of malignancy who were treated in the Meander Medical Centre, Amersfoort, the Netherlands, in the years 1994-2001 with chemotherapy consisting of cyclophosphamide, doxorubicin, vincristine and prednisone (CHOP). This took place either in routine clinical practice (RCP) or as part of a clinical trial where patients < or = 60 years of age received intensified CHOP and patients > 60 years received CHOP with growth factors. Treatment data, the response to therapy, survival and prognostic factors according to the International Prognostic Index for aggressive NHL were collected by a review of the patient records. RESULTS: Fifty-nine patients were eligible for this analysis: 32 men and 27 women with a median age of 63 years (range 30-83). Of these, 35 were treated within a clinical trial and 24 were treated in RCP. The patient characteristics in the two groups were comparable. There was no difference in median survival between the trial and RCP groups, this being 27 months for all patients, 34 months for the younger patients, 20 months for the elderly patients, and 42 months for patients who achieved complete remission following chemotherapy. CONCLUSION: No difference in overall survival was found between patients with disseminated aggressive NHL who underwent treatment according to either RCP or as part of a clinical trial. It demonstrates that both patients in clinical trials and patients treated according to RCP received equally effective therapy. Recent developments in NHL treatments are promising, and therefore participation in clinical trials should be encouraged.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Ciclofosfamida/uso terapéutico , Doxorrubicina/uso terapéutico , Linfoma no Hodgkin/tratamiento farmacológico , Linfoma no Hodgkin/mortalidad , Prednisona/uso terapéutico , Vincristina/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Ensayos Clínicos Fase III como Asunto , Femenino , Sustancias de Crecimiento/uso terapéutico , Humanos , Masculino , Persona de Mediana Edad , Ensayos Clínicos Controlados Aleatorios como Asunto , Inducción de Remisión , Estudios Retrospectivos , Análisis de Supervivencia , Resultado del TratamientoRESUMEN
Epstein-Barr virus lymphoproliferative disease (EBV-LPD) following allogeneic stem cell transplantation (allo-SCT) has a poor prognosis. We used a sensitive real-time polymerase chain reaction (PCR) assay for quantitative detection of EBV-DNA in plasma and serially measured EBV-DNA levels to assess the response to treatment in allo-SCT recipients with EBV-LPD. Fourteen allo-SCT recipients with EBV-LPD who received a T cell-depleted (TCD) sibling (n = 5) or matched unrelated donor (n = 9) graft were monitored from the time of EBV-LPD diagnosis, during therapy and assessment of clinical response. Seven patients had complete responses of EBV-LPD to therapy, of whom 21% (3 out of 14) survived beyond 6 months from EBV-LPD diagnosis. Clinically responding patients showed a rapid decline of EBV-DNA plasma levels within 72 h from the start of therapy. In contrast, all clinical non-responders showed an increase of EBV-DNA levels. Absolute EBV-DNA levels at the time of EBV-LPD diagnosis did not predict for response, but the pattern of EBV-DNA levels within 72 h from the start of therapy (> 50% decrease versus increase) strongly predicted for clinical response (P = 0.001). Quantitative monitoring of EBV-DNA levels from the start of and during therapy for EBV-LPD rapidly and accurately predicts for response to therapy as early as within 72 h. It may thus provide a powerful tool to adjust and select treatment in individuals with EBV-LPD following allo-SCT.
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ADN Viral/sangre , Trasplante de Células Madre Hematopoyéticas , Herpesvirus Humano 4/genética , Trastornos Linfoproliferativos/cirugía , Trastornos Linfoproliferativos/virología , Enfermedad Aguda , Adulto , Anemia Aplásica/mortalidad , Anemia Aplásica/cirugía , Anemia Aplásica/virología , Femenino , Estudios de Seguimiento , Humanos , Leucemia Mielógena Crónica BCR-ABL Positiva/mortalidad , Leucemia Mielógena Crónica BCR-ABL Positiva/cirugía , Leucemia Mielógena Crónica BCR-ABL Positiva/virología , Leucemia Mieloide/mortalidad , Leucemia Mieloide/cirugía , Leucemia Mieloide/virología , Leucemia Mielomonocítica Crónica/mortalidad , Leucemia Mielomonocítica Crónica/cirugía , Leucemia Mielomonocítica Crónica/virología , Trastornos Linfoproliferativos/mortalidad , Masculino , Persona de Mediana Edad , Mieloma Múltiple/mortalidad , Mieloma Múltiple/cirugía , Mieloma Múltiple/virología , Reacción en Cadena de la Polimerasa/métodos , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidad , Leucemia-Linfoma Linfoblástico de Células Precursoras/cirugía , Leucemia-Linfoma Linfoblástico de Células Precursoras/virología , Pronóstico , Tasa de Supervivencia , Trasplante Homólogo , Carga ViralRESUMEN
Mantle cell lymphoma (MCL) is an aggressive neoplasm characterized by the deregulated expression of cyclin D1 by t(11;14). The molecular mechanisms responsible for MCL's clinical behavior remain unclear. The authors have investigated the expression of p53, E2F-1, and the CDK inhibitors p27 and p21 in 110 MCLs, relating their expression to proliferative activity (Ki-67). For comparison, they have similarly analyzed low-grade (12 MALT, 16 CLL/SLL) and high-grade (19 DLCL) lymphomas. p53 was detected more frequently in large-cell MCL (l-MCL; 5 of 7) than in classical MCL (s-MCL; 13 of 103) and DLCL (8 of 19). In MCL and DLCL, the percentage of E2F-1+ nuclei was high, correlating with high Ki-67 expression. Most MCLs (91 of 112) and DLCLs (12 of 19) showed a loss of p27; MALT and CLL/SLL, however, were p27 positive. Reverse transcription-polymerase chain reaction and in vitro protein degradation assays demonstrated that MCLs have normal p27 mRNA expression but increased p27 protein degradation activity via the proteasome pathway. Correlation of MCL p53 and p27 expression with clinical data showed an association between reduced overall survival rates and the overexpression of p53 (P =.001), the loss of p27 (P =. 002), or both. Loss of p27 identified patients with a worse clinical outcome among p53 negative cases (P =.002). These findings demonstrated that MCL has a distinct cell cycle protein expression similar to that of high-grade lymphoma. The loss of p27 and the overexpression of p53 in MCL are prognostic markers that identify patients at high risk. The demonstration that low levels of p27 in MCL result from enhanced proteasome-mediated degradation should encourage additional clinical trials. (Blood. 2000;95:619-626) (Blood. 2000;95:619-626)
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Proteínas Portadoras , Proteínas de Ciclo Celular , Quinasas Ciclina-Dependientes/antagonistas & inhibidores , Cisteína Endopeptidasas/metabolismo , Proteínas de Unión al ADN , Linfoma de Células del Manto/genética , Proteínas Asociadas a Microtúbulos/genética , Proteínas Asociadas a Microtúbulos/metabolismo , Complejos Multienzimáticos/metabolismo , Proteínas Supresoras de Tumor , Linfocitos B/metabolismo , Biomarcadores de Tumor/análisis , Biomarcadores de Tumor/genética , Inhibidor p21 de las Quinasas Dependientes de la Ciclina , Inhibidor p27 de las Quinasas Dependientes de la Ciclina , Ciclinas/genética , Factores de Transcripción E2F , Factor de Transcripción E2F1 , Humanos , Antígeno Ki-67/análisis , Tejido Linfoide/metabolismo , Linfoma/genética , Linfoma/patología , Linfoma de Células B de la Zona Marginal/genética , Linfoma de Células B de la Zona Marginal/mortalidad , Linfoma de Células B de la Zona Marginal/patología , Linfoma de Células del Manto/mortalidad , Linfoma de Células del Manto/patología , Linfoma de Células del Manto/cirugía , Complejo de la Endopetidasa Proteasomal , Proteína 1 de Unión a Retinoblastoma , Tasa de Supervivencia , Factor de Transcripción DP1 , Factores de Transcripción/genética , Proteína p53 Supresora de Tumor/genéticaRESUMEN
Receptors of most hematopoietic growth factors are structurally related and grouped in the hematopoietin or cytokine receptor superfamily. In this paper, we will first review the general principles of hematopoietin receptor complex formation and cytoplasmic signaling. Subsequently, the significance of defective hematopoietic growth factor receptors for the development of hematological diseases will be discussed.
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Sustancias de Crecimiento/química , Hematopoyesis , Receptores del Factor Estimulante de Colonias/química , Secuencia de Aminoácidos , Animales , Humanos , Ligandos , Datos de Secuencia Molecular , Agregación de Receptores , Transducción de SeñalRESUMEN
The relative affinity of recombinant human interleukin-3 (IL-3) binding to normal rhesus monkey bone marrow cells was found to be 25- to 50-fold less than that of homologous IL-3, which explained the species specificity of human IL-3 observed when tested in Macaca species. In contrast, only a small difference was found between human and rhesus monkey IL-3 in relative binding affinity for receptors on human acute myelogenous leukemia (AML) cells, which confirmed that the species specificity of IL-3 is largely unidirectional. The biological significance of the findings was demonstrated by direct in vivo comparison of the effects of high-dose recombinant rhesus monkey and human IL-3. The binding characteristics of IL-3 receptors on rhesus monkey bone marrow and peripheral blood cells were further characterized by specific binding of radiolabeled rhesus monkey IL-3. Scatchard analysis of two bone marrow samples demonstrated high-affinity IL-3 receptors (25 and 80 sites/cell, respectively; equilibrium dissociation constants [Kd] of 8 and 3 pM/L) as well as low-affinity receptors (1070 and 1290 sites/cell; equilibrium dissociation constants of 2600 and 1200 pM/L). In addition, IL-3 receptor expression was also detected on purified CD34-positive bone marrow cells. Competition by human granulocyte-macrophage colony-stimulating factor (GM-CSF) of IL-3 binding to high- or low-affinity receptors on rhesus monkey peripheral blood and bone marrow cells could not be demonstrated, which may indicate that the growth factor-specific alpha-subunits of the GM-CSF and IL-3 receptors are expressed predominantly on different cell types.
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Células de la Médula Ósea , Médula Ósea/química , Factor Estimulante de Colonias de Granulocitos y Macrófagos/metabolismo , Interleucina-3/metabolismo , Receptores de Interleucina-3/análisis , Receptores de Interleucina-3/metabolismo , Animales , Antígenos CD/análisis , Antígenos CD34 , Unión Competitiva , Médula Ósea/ultraestructura , Células Cultivadas , Relación Dosis-Respuesta a Droga , Células Madre Hematopoyéticas/química , Células Madre Hematopoyéticas/citología , Células Madre Hematopoyéticas/metabolismo , Histamina/farmacología , Humanos , Radioisótopos de Yodo , Leucemia Mieloide Aguda/patología , Macaca mulatta , Masculino , Especificidad de la Especie , Células Tumorales CultivadasRESUMEN
Acute myeloid leukemia blasts express dual affinity (high and low) granulocyte-macrophage colony-stimulating factor (GM-CSF) binding, and the high affinity GM-CSF binding is counteracted by excess interleukin-3 (IL-3). Neutrophils express a single class of GM-CSF-R with intermediate affinity that lack IL-3 cross-reactivity. Here we demonstrate the differentiation associated changes of GM-CSF binding characteristics in three models representative of different stages of myeloid maturation. We find that high affinity GM-CSF binding is converted into intermediate affinity binding, which still cross-reacts with IL-3, beyond the stage of promyelocytes. During terminal maturation towards neutrophils, IL-3 cross-reactivity is gradually lost. We sought to determine the mechanism underlying the affinity conversion of the GM-CSF-R. Northern and reverse transcriptase-polymerase chain reaction analysis of GM-CSF-R alpha and -beta c (KH97) transcripts did not provide indications for the involvement of GM-CSF-R splice variants in the formation of the intermediate affinity GM-CSFR complex. In COS-cell transfectants with increasing amounts of beta c in the presence of a fixed number of GM-CSF-R alpha chains, the high affinity GM-CSF binding converted into intermediate affinity GM-CSF binding. These results are discussed in view of the concept that increasing expression of beta c subunits may cause alternative oligomerization of the GM-CSF-R alpha and -beta c subunits resulting in the formation of intermediate rather than high affinity GM-CSFR alpha.beta c complexes.
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Factor Estimulante de Colonias de Granulocitos y Macrófagos/metabolismo , Factor Estimulante de Colonias de Granulocitos y Macrófagos/farmacología , Leucemia Mielógena Crónica BCR-ABL Positiva/metabolismo , Leucemia Mieloide/metabolismo , Receptores de Factor Estimulante de Colonias de Granulocitos y Macrófagos/genética , Receptores de Factor Estimulante de Colonias de Granulocitos y Macrófagos/metabolismo , Enfermedad Aguda , Animales , Secuencia de Bases , Línea Celular , Humanos , Cinética , Leucemia Mielógena Crónica BCR-ABL Positiva/patología , Leucemia Mieloide/patología , Leucemia Promielocítica Aguda , Sustancias Macromoleculares , Datos de Secuencia Molecular , Oligodesoxirribonucleótidos , Reacción en Cadena de la Polimerasa/métodos , ARN Neoplásico/genética , ARN Neoplásico/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacología , Eliminación de Secuencia , Transcripción Genética , Transfección , Tretinoina/farmacología , Células Tumorales Cultivadas , Regulación hacia ArribaRESUMEN
We have investigated the stimulative effects of mast cell growth factor (MGF) in primary acute myeloid leukemia (AML) in vitro. MGF stimulated DNA synthesis of purified leukemic blasts in eight out of 10 cases and colony formation in four cases in serum-free (SF) culture. MGF synergized with interleukin-3 (IL-3; four out of 10 cases), granulocyte-macrophage colony-stimulating factor (GM-CSF; three out of 10 cases), granulocyte colony-stimulating factor (G-CSF; six out of 10 cases), macrophage colony-stimulating factor (M-CSF; one out of 10 cases) and erythropoietin (EPO; one out of 10 cases) when added to culture in combination. Synergistic effects of MGF in combination with other CSFs were also seen in the colony assay. Antibodies against GM-CSF, M-CSF, G-CSF, and IL-6 did not inhibit the MGF response, suggesting that the stimulative effect of MGF was not mediated through autocrine release of those cytokines. Cell recovery data in liquid cultures that contained MGF, IL-3, or MGF + IL-3, indicated that both MGF and IL-3 augmented the maintenance of clonogenic cells as compared to nonsupplemented cultures, but the effect of the combination of IL-3 + MGF did not show synergy. In contrast, activation of DNA synthesis by MGF was abrogated in the presence of tumor necrosis factor (TNF; four out of 10 cases) and interleukin-4 (IL-4; two out of 10 cases). Fluorescence-activated cell sorting (FACS) analysis with anti c-kit antibodies revealed MGF receptor expression in eight out of nine cases, often in a subpopulation of the cells. Scatchard analysis of MGF receptors in two cases indicated the presence of 1460 and 41,500 (mean) binding sites, respectively, of high affinity (Kd 40-160 pmol/l). The MGF dose-response curve in the presence of IL-3 or GM-CSF resulted in a higher plateau of DNA synthesis, however no shift in the dose response was apparent. The respective reciprocal dose response relations to GM-CSF, IL-3, or G-CSF were similarly elevated when MGF was added. MGF did not alter IL-3 and GM-CSF receptor expression, nor did IL-3, GM-CSF, G-CSF, TNF, or IL-4 influence MGF binding to AML cells.(ABSTRACT TRUNCATED AT 400 WORDS)
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Citocinas/farmacología , Factores de Crecimiento de Célula Hematopoyética/farmacología , Leucemia Mieloide/tratamiento farmacológico , Enfermedad Aguda , Anticuerpos/farmacología , División Celular/efectos de los fármacos , División Celular/fisiología , Interacciones Farmacológicas , Sinergismo Farmacológico , Factor Estimulante de Colonias de Granulocitos/farmacología , Factores de Crecimiento de Célula Hematopoyética/inmunología , Factores de Crecimiento de Célula Hematopoyética/fisiología , Humanos , Interleucina-3/farmacología , Leucemia Monocítica Aguda/tratamiento farmacológico , Leucemia Monocítica Aguda/patología , Leucemia Mieloide/patología , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/patología , Leucemia Mielomonocítica Aguda/tratamiento farmacológico , Leucemia Mielomonocítica Aguda/patología , Proteínas Proto-Oncogénicas/efectos de los fármacos , Proteínas Proto-Oncogénicas/fisiología , Proteínas Proto-Oncogénicas c-kit , Receptores de Factor Estimulante de Colonias de Granulocitos y Macrófagos/efectos de los fármacos , Receptores de Factor Estimulante de Colonias de Granulocitos y Macrófagos/fisiología , Receptores de Interleucina-3/efectos de los fármacos , Receptores de Interleucina-3/fisiología , Sensibilidad y Especificidad , Factor de Células Madre , Células Tumorales Cultivadas/efectos de los fármacos , Regulación hacia Arriba/efectos de los fármacosRESUMEN
Tumor necrosis factor (TNF) inhibits granulocyte-colony-stimulating factor (G-CSF)-induced human acute myeloid leukemia (AML) growth in vitro. Incubation of blasts from three patients with AML in serum-free medium with TNF (10(3) U/ml), and subsequent binding studies using 125I-G-CSF reveal that TNF downregulates the numbers of G-CSF receptors by approximately 70%. G-CSF receptor numbers on purified blood granulocytes are also downmodulated by TNF. Downregulation of G-CSF receptor expression becomes evident within 10 min after incubation of the cells with TNF at 37 degrees C and is not associated with an apparent change of the dissociation constant (Kd). The TNF effect does not occur at 0 degrees C and cannot be induced by IL-2, IL-6, or GM-CSF. TNF probably exerts its effect through activation of protein kinase C (PKC) as the TNF effect on G-CSF receptor levels can be mimicked by 12-O-tetradecanoylphorbol-13- acetate. The PKC inhibitor Staurosporine (Sigma Chemical Co., St. Louis, MO) as well as protease inhibitors can completely prevent G-CSF receptor downmodulation. Thus, it appears TNF may act as a regulator of G-CSF receptor expression in myeloid cells and shut off G-CSF dependent hematopoiesis. The regulatory ability of TNF may explain the antagonism between TNF and G-CSF stimulation.
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Factor Estimulante de Colonias de Granulocitos/metabolismo , Granulocitos/fisiología , Leucemia Mieloide/metabolismo , Receptores de Factor Estimulante de Colonias de Granulocito/genética , Factor de Necrosis Tumoral alfa/farmacología , Enfermedad Aguda , Alcaloides/farmacología , Regulación hacia Abajo/efectos de los fármacos , Granulocitos/efectos de los fármacos , Humanos , Técnicas In Vitro , Inhibidores de Proteasas/farmacología , Estaurosporina , Acetato de Tetradecanoilforbol/farmacología , Factores de TiempoRESUMEN
Tumor necrosis factor (TNF) acts as a potent enhancer of granulocyte-macrophage colony-stimulating factor (GM-CSF)- and interleukin-3 (IL-3)-induced human acute myeloid leukemia (AML) growth in vitro. We have analyzed the effects of TNF alpha on the expression of GM-CSF and IL-3 receptors on AML cells. Incubation of blasts from seven patients with AML in serum-free medium with TNF (10(3) U/mL) and subsequent binding studies using 125I-GM-CSF and 125I-IL-3 show that TNF increases the specific binding of GM-CSF (30% to 280%) and IL-3 (40% to 600%) in all cases. From Scatchard plot analysis it appears that TNF upregulates (1) low-affinity GM-CSF binding sites, (2) common high-affinity IL-3/GM-CSF binding sites, and (3) unique (non-GM-CSF binding) IL-3 binding sites. The effect of TNF is dose dependent and is half maximal at a concentration of 100 U/mL, and becomes evident at 18 hours of incubation with TNF at 37 degrees C, but not at 0 degree C. The GM-CSF dose-response curve of AML-colony-forming units plateaus at a higher level in the presence of TNF, which indicates that additional numbers of cells become responsive to GM-CSF. Incubation of AML blasts with the phorbol ester 12-0-tetradecanoylphorbol-13-acetate or formyl-Met-Leu-Phe (protein kinase C activators) does not influence GM-CSF receptor expression, suggesting that receptor upregulation by TNF is not mediated through activation of protein kinase C. On the other hand, the protein synthesis inhibitor cycloheximide abrogates receptor upregulation induced by TNF. In contrast to these findings in AML, TNF does not upregulate GM-CSF receptor numbers on blood granulocytes or monocytes. We conclude that TNF exerts positive effects on growth factor receptor expression of hematopoietic cells.
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Factor Estimulante de Colonias de Granulocitos y Macrófagos/metabolismo , Leucemia Monocítica Aguda/metabolismo , Leucemia Mieloide Aguda/metabolismo , Leucemia Mielomonocítica Aguda/metabolismo , Receptores de Factor Estimulante de Colonias de Granulocitos y Macrófagos/metabolismo , Receptores de Interleucina-3/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Factor de Necrosis Tumoral alfa/farmacología , Cicloheximida/farmacología , Relación Dosis-Respuesta a Droga , Humanos , Técnicas In Vitro , Interleucina-3/metabolismo , Proteína Quinasa C/metabolismo , Regulación hacia Arriba/efectos de los fármacosRESUMEN
Granulocyte macrophage colony-stimulating factor (GM-CSF) and interleukin-3 (IL-3) control the proliferation of human acute myeloid leukemia (AML) cells in vitro. Previously, we have shown that receptors for GM-CSF and IL-3 are often coexpressed on AML cells. Here we present experiments with purified AML blasts, normal monocytes, and granulocytes that were conducted to analyze the properties of GM-CSF and IL-3 binding proteins in more detail. On AML cells from eight cases we demonstrate two types of GM-CSF receptors: one with low affinity (dissociation constant [kd] 5.1 to 24.8 nmol/L) and one with a high affinity (kd 31 to 104 pmol/L). These AML cells also expressed high affinity receptors for IL-3 (kd 24 to 104 pmol/L). Cross-competition experiments showed that an excess concentration of nonlabeled IL-3 completely prevented the high affinity binding of radiolabled GM-CSF. This competition occurred at 37 degrees C as well as 4 degrees C. Low affinity GM-CSF binding was not affected by IL-3. Binding of radiolabeled IL-3 could be prevented by nonlabeled GM-CSF. In certain cases, this competition was complete, whereas in others only partial (49% to 77%) reduction of the radiolabeled IL-3 binding was seen. On the basis of these ligand binding features, we propose the existence of three receptor types on AML cells: (1) low affinity GM-CSF receptors that do not bind IL-3, (2) dual high affinity GM-CSF/IL-3 receptors, and (3) high affinity IL-3 receptors that do not bind GM-CSF. We could also demonstrate these receptor types on normal monocytes. In addition, a fourth type of receptor was apparent on normal granulocytes (4), incapable of binding IL-3 and with an intermediate affinity for GM-CSF (approximately 400 pmol/L). Chemical crosslinking showed that GM-CSF and IL-3 both bind to proteins with molecular weight values of 130, 105, and 75, which provides additional evidence for the existence of a common GM-CSF/IL-3 receptor complex.
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Factores Estimulantes de Colonias/metabolismo , Sustancias de Crecimiento/metabolismo , Interleucina-3/metabolismo , Leucemia Mieloide Aguda/metabolismo , Monocitos/metabolismo , Receptores de Superficie Celular/metabolismo , Receptores Inmunológicos/metabolismo , Unión Competitiva , Membrana Celular/inmunología , Membrana Celular/metabolismo , Factores Estimulantes de Colonias/farmacología , Factor Estimulante de Colonias de Granulocitos y Macrófagos , Sustancias de Crecimiento/farmacología , Humanos , Cinética , Leucemia Mieloide Aguda/sangre , Leucemia Mieloide Aguda/inmunología , Peso Molecular , Monocitos/inmunología , Receptores de Superficie Celular/efectos de los fármacos , Receptores de Superficie Celular/aislamiento & purificación , Receptores del Factor Estimulante de Colonias , Receptores de Interleucina-3 , Proteínas Recombinantes/metabolismo , TermodinámicaRESUMEN
The binding of granulocyte colony-stimulating factor (G-CSF) to normal and human acute myeloid leukemia (AML) cells was investigated with radiolabeled recombinant human G-CSF (rhG-CSF). In all 14 cases of primary AML specific receptors for G-CSF were demonstrated on purified blast cells. The average numbers of G-CSF receptors ranged from very low to 428 receptors per cell (mean). Normal granulocytes showed G-CSF binding sites on their surface at higher densities (703 to 1,296 sites per cell). G-CSF receptors appeared to be of a single affinity type with a dissociation constant (kd) ranging between 214 and 378 pmol/L for AML blasts and 405 to 648 pmol/L for granulocytes. In 12 of 14 cases, including those with relatively low specific binding, G-CSF was a potent inducer of DNA synthesis of blasts in vitro; therefore, apparently relatively few receptors are required to permit activation of AML cell growth. However, in two cases cell cycling was not activated in response to G-CSF despite G-CSF receptor availability. The results show that G-CSF receptors of high affinity are frequently expressed on the blasts of human AML, but their presence may not be a strict indicator of the proliferative responsiveness of the cells to G-CSF.
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Factores Estimulantes de Colonias/metabolismo , Leucemia Mieloide Aguda/metabolismo , Receptores de Superficie Celular/metabolismo , División Celular/efectos de los fármacos , Factores Estimulantes de Colonias/farmacología , Factor Estimulante de Colonias de Granulocitos , Granulocitos/metabolismo , Humanos , Leucemia Mieloide Aguda/patología , Receptores de Factor Estimulante de Colonias de Granulocito , Células Tumorales CultivadasRESUMEN
Interleukin-3 (IL-3) and granulocyte-monocyte-colony-stimulating factor (GM-CSF) stimulate proliferation of human acute myeloid leukemia (AML) in vitro, although patterns of response among clinical cases are diverse. Whether regulatory abnormalities related to growth factor responses in human AML may establish the outgrowth of the neoplasm is unclear. We determined receptor numbers and affinity for IL-3 and GM-CSF on human AML cells using human recombinant IL-3 (rIL-3) and GM-CSF (rGM-CSF). In 13 of 15 cases of primary AML high-affinity (kd 26 to 414 pmol/L) receptors for IL-3 were demonstrable on the cells. The average numbers of IL-3 receptors ranged from 21 to 145 receptors per cell. Normal WBCs showed IL-3 receptors on their surface at similar densities. IL-3 receptor positivity often correlated with GM-CSF receptor positivity of AML; GM-CSF receptors were demonstrated on the cells of 11 of 15 cases, although average numbers of GM-CSF receptors were ten times greater. The in vitro response of the cells to exogenous IL-3 or GM-CSF was examined by measuring thymidine uptake. Because IL-3 and GM-CSF were potent inducers of DNA synthesis in vitro, apparently relatively few receptors are required to permit activation of growth. These experiments did not provide evidence for overexpression or increased receptor sensitivity as an explanation for AML growth. In a minority of cases, however, the cells were unable to respond to IL-3 (four of 15 cases) or GM-CSF (four of 15 cases) despite normal receptor availability on the cell surface.