RESUMO
We describe a spectrin variant characterized by a truncated beta chain and associated with hereditary spherocytosis. The clinical phenotype consists of a moderate hemolytic anemia with striking spherocytosis and mild spiculation of the red cells. We describe the biochemical characteristics of this truncated protein which constitutes only 10% of the total beta spectrin present on the membrane, resulting in spectrin deficiency. Analysis of reticulocyte cDNA revealed the deletion of exons 22 and 23. We show, using Southern blot analysis, that this truncation results from a 4.6-kb genomic deletion. To elucidate the basis for the decreased amount of the truncated protein on the membrane and the overall spectrin deficiency, we show that (a) the mutated gene is efficiently transcribed and its mRNA abundant in reticulocytes, (b) the mutant protein is normally synthesized in erythroid progenitor cells, (c) the stability of the mutant protein in the cytoplasm of erythroblasts parallels that of the normal beta spectrin, and (d) the abnormal protein is inefficiently incorporated into the membrane of erythroblasts. We conclude that the truncation within the beta spectrin leads to inefficient incorporation of the mutant protein into the skeleton despite its normal synthesis and stability. We postulate that this misincorporation results from conformational changes of the beta spectrin subunit affecting the binding of the abnormal heterodimer to ankyrin, and we provide evidence based on binding assays of recombinant synthetic peptides to inside-out-vesicles to support this model.
Assuntos
Anquirinas/metabolismo , Variação Genética , Espectrina/deficiência , Espectrina/genética , Esferocitose Hereditária/genética , Sequência de Bases , Sítios de Ligação , Southern Blotting , Pré-Escolar , Clonagem Molecular , Citoplasma/metabolismo , Primers do DNA , Eritroblastos/metabolismo , Membrana Eritrocítica/metabolismo , Feminino , Humanos , Substâncias Macromoleculares , Masculino , Proteínas de Membrana/biossíntese , Proteínas de Membrana/sangue , Proteínas de Membrana/isolamento & purificação , Modelos Moleculares , Dados de Sequência Molecular , Fragmentos de Peptídeos/síntese química , Fragmentos de Peptídeos/metabolismo , Reação em Cadeia da Polimerase , Conformação Proteica , RNA Mensageiro/análise , RNA Mensageiro/biossíntese , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/isolamento & purificação , Reticulócitos/metabolismo , Espectrina/química , Esferocitose Hereditária/sangueRESUMO
While outcomes for children with T-cell acute lymphoblastic leukemia (T-ALL) have improved dramatically, survival rates for patients with relapsed/refractory disease remain dismal. Prior studies indicate that glucocorticoid (GC) resistance is more common than resistance to other chemotherapies at relapse. In addition, failure to clear peripheral blasts during a prednisone prophase correlates with an elevated risk of relapse in newly diagnosed patients. Here we show that intrinsic GC resistance is present at diagnosis in early thymic precursor (ETP) T-ALLs as well as in a subset of non-ETP T-ALLs. GC-resistant non-ETP T-ALLs are characterized by strong induction of JAK/STAT signaling in response to interleukin-7 (IL7) stimulation. Removing IL7 or inhibiting JAK/STAT signaling sensitizes these T-ALLs, and a subset of ETP T-ALLs, to GCs. The combination of the GC dexamethasone and the JAK1/2 inhibitor ruxolitinib altered the balance between pro- and anti-apoptotic factors in samples with IL7-dependent GC resistance, but not in samples with IL7-independent GC resistance. Together, these data suggest that the addition of ruxolitinib or other inhibitors of IL7 receptor/JAK/STAT signaling may enhance the efficacy of GCs in a biologically defined subset of T-ALL.
Assuntos
Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos , Glucocorticoides/farmacologia , Interleucina-7/metabolismo , Janus Quinases/metabolismo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/metabolismo , Fatores de Transcrição STAT/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Antineoplásicos/uso terapêutico , Proteína 11 Semelhante a Bcl-2/metabolismo , Linhagem Celular Tumoral , Dexametasona/farmacologia , Modelos Animais de Doenças , Humanos , Inibidores de Janus Quinases/farmacologia , Camundongos , Leucemia-Linfoma Linfoblástico de Células T Precursoras/tratamento farmacológico , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Ras GTPases are activated by RasGEFs and inactivated by RasGAPs, which stimulate the hydrolysis of RasGTP to inactive RasGDP. GTPase-impairing somatic mutations in RAS genes, such as KRAS(G12D), are among the most common oncogenic events in metastatic cancer. A different type of cancer Ras signal, driven by overexpression of the RasGEF RasGRP1 (Ras guanine nucleotide-releasing protein 1), was recently implicated in pediatric T-cell acute lymphoblastic leukemia (T-ALL) patients and murine models, in which RasGRP1 T-ALLs expand in response to treatment with interleukins (ILs) 2, 7 and 9. Here, we demonstrate that IL-2/7/9 stimulation activates Erk and Akt pathways downstream of Ras in RasGRP1 T-ALL but not in normal thymocytes. In normal lymphocytes, RasGRP1 is recruited to the membrane by diacylglycerol (DAG) in a phospholipase C-γ (PLCγ)-dependent manner. Surprisingly, we find that leukemic RasGRP1-triggered Ras-Akt signals do not depend on acute activation of PLCγ to generate DAG but rely on baseline DAG levels instead. In agreement, using three distinct assays that measure different aspects of the RasGTP/GDP cycle, we established that overexpression of RasGRP1 in T-ALLs results in a constitutively high GTP-loading rate of Ras, which is constantly counterbalanced by hydrolysis of RasGTP. KRAS(G12D) T-ALLs do not show constitutive GTP loading of Ras. Thus, we reveal an entirely novel type of leukemogenic Ras signals that is based on a RasGRP1-driven increased in flux through the RasGTP/GDP cycle, which is mechanistically very different from KRAS(G12D) signals. Our studies highlight the dynamic balance between RasGEF and RasGAP in these T-ALLs and put forth a new model in which IL-2/7/9 decrease RasGAP activity.
Assuntos
Citocinas/farmacologia , Proteínas de Ligação a DNA/metabolismo , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas ras/metabolismo , Animais , Western Blotting , Linhagem Celular Tumoral , Criança , Diglicerídeos/metabolismo , Guanosina Difosfato/metabolismo , Guanosina Trifosfato/metabolismo , Humanos , Interleucina-2/farmacologia , Interleucina-7/farmacologia , Interleucina-9/farmacologia , Camundongos , Fosfolipase C gama/metabolismo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , Receptores de Citocinas/metabolismo , Transdução de Sinais/efeitos dos fármacosRESUMO
Acute lymphoblastic leukemia (ALL), the most common cancer in childhood, is characterized by clonal proliferation of transformed lymphoblasts that comprise the majority of marrow and/or blood specimens. Although the leukemic cells typically express antigens associated with lymphoid maturation or activation (ie CD19, CD38, etc), it has been suggested that ALL blasts may evolve from a more primitive precursor. Increased understanding of the phenotypic and molecular heterogeneity of cells in ALL may provide clues to leukemogenesis and/ or impact prognostication or treatment. We utilized a phenotype/genotype approach to measure the prevalence and frequency of cytogenetically aberrant cells in a phenotypically defined primitive compartment (CD34+33-19-38-; CD34+Lin-). Bone marrow cells were flow cytometrically sorted into CD34-Lin+, CD34+Lin+ and CD34+Lin- subpopulations. Fluorescence in situ hybridization (FISH) was used to quantify the frequency of cells with aneusomies in the sorted populations. Approximately 26% (5/19) of ALL cases at diagnosis contain cytogenetically aberrant CD34+Lin- cells. The frequency of cytogenetically aberrant cells in the CD34+Lin- compartment is independent of FAB, WBC and blast counts. These data indicate that cytogenetically aberrant cells may reside in a phenotypically defined primitive subpopulation and suggest that ALL blasts in some patients may evolve from a precursor compartment.
Assuntos
Medula Óssea/patologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , ADP-Ribosil Ciclase , ADP-Ribosil Ciclase 1 , Adolescente , Aneuploidia , Antígenos CD/análise , Antígenos CD19/análise , Antígenos CD34/análise , Antígenos de Diferenciação/análise , Antígenos de Diferenciação Mielomonocítica/análise , Criança , Pré-Escolar , Aberrações Cromossômicas , Feminino , Citometria de Fluxo , Humanos , Imunofenotipagem , Hibridização in Situ Fluorescente , Lactente , Masculino , Glicoproteínas de Membrana , NAD+ Nucleosidase/análise , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Lectina 3 Semelhante a Ig de Ligação ao Ácido SiálicoRESUMO
The Philadelphia chromosome translocation t(9;22)(q34;q11) may give rise to different BCR/ABL fusion mRNAs due to different genomic breakpoints and alternative splicing. The e1a2, b2a2 or b3a2 and c3a2 fusion mRNAs encode distinct fusion proteins (p190, p210 and p230, respectively), which are associated with different forms of leukemogenesis in humans and animal models. Our patient presented with acute pre-B cell lymphoblastic leukemia (ALL) with normal cytogenetics. After 3 years of standard ALL therapy, he relapsed with t(9;22)-positive chronic myelogenous leukemia (CML). Retrospective molecular analyses of the pre-treatment pre-B cell ALL sample showed the b3a2 (p210) and e1a2 (p190) BCR/ABL fusion transcripts. Only the b3a2 (p210) transcript was detected at relapse. Southern and immunoglobulin heavy chain (IgH) analyses of the presentation and relapse samples revealed an identical BCR rearrangement in both samples. However, only the ALL sample harbored an IgH gene rearrangement. These findings show a clonal relationship between the more differentiated pre-B cell and less differentiated CML clones and that the p210 and p190 fusion mRNAs were alternatively spliced from a single genomic breakpoint. Our patient's unusual molecular findings provide circumstantial evidence that the p190 protein may promote a more differentiated phenotype in a comparatively less differentiated p210-transformed precursor cell.
Assuntos
Proteínas de Fusão bcr-abl/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , RNA Mensageiro/análise , Adolescente , Rearranjo Gênico , Genes de Imunoglobulinas , Humanos , Masculino , Cromossomo Filadélfia , RecidivaRESUMO
Significant predictors of treatment outcome are poorly defined for patients with T-lineage acute lymphoblastic leukemia (T-ALL). A high WBC at diagnosis, which has traditionally been a predictor of poor response in T-ALL, has considerably weakened prognostic significance in the face of modern, more intensive chemotherapy. To test the hypothesis that bone marrow stroma-supported leukemic cell recovery might identify children at high risk for relapse, we measured the ex vivo recovery of T-ALL lymphoblasts from 29 newly diagnosed patients using a stromal cell co-culture assay. In all cases the T-ALL lymphoblasts showed an increase in recovery of T-ALL cells (RTC), ranging from 4 to 343%, in comparison to samples maintained without stroma. Since we were blinded to patient outcome in this case-control study, we then correlated patient outcome with RTC. The RTC for 18 patients in complete continuous remission (CCR) for greater than 4 years was stochastically larger than for the 11 patients who eventually relapsed (P = 0.011, by the two-sided Wilcoxon test). Furthermore, 100% of patients with an RTC of more than 26% had a CCR greater than 4 years while 78% of the patients with an RTC of less than 25% relapsed within 4 years. This is the first report to show that higher lymphoblast recovery may predict a more favorable outcome for children with T-ALL. A prospective study is needed to test whether stroma-supported leukemic cell recovery might serve as a basis for assigning risk-adjusted therapy.
Assuntos
Células da Medula Óssea/citologia , Técnicas de Cocultura/métodos , Leucemia-Linfoma de Células T do Adulto/tratamento farmacológico , Recidiva Local de Neoplasia/diagnóstico , Células Estromais/fisiologia , Adolescente , Adulto , Estudos de Casos e Controles , Linhagem Celular , Linhagem da Célula , Sobrevivência Celular , Criança , Pré-Escolar , Humanos , Lactente , Leucemia-Linfoma de Células T do Adulto/diagnóstico , Leucemia-Linfoma de Células T do Adulto/patologia , Contagem de Leucócitos , Resultado do Tratamento , Células Tumorais CultivadasRESUMO
Distinction of normal B-lymphoid proliferations including precursors known as hematogones from acute lymphoblastic leukemia (ALL) is critical for disease management. We present a multiparameter assessment of 27 bone marrow samples containing at least 25% hematogones (range, 25%-72%) by morphologic review. We used flow cytometry to evaluate B-cell differentiation antigen and adhesion molecule expression and immunohistochemistry on clot sections to evaluate architectural distribution. Flow cytometry revealed that intermediately differentiated cells (CD19+, CD10+) predominated, followed in frequency by CD20+, surface immunoglobulin-positive cells, with CD34+, terminal deoxynucleotidyl transferase (TdT)-positive cells as the smallest subset. Adhesion molecules (CD44, CD54) were expressed more heterogeneously compared with expression in acute lymphoblastic leukemia. Immunohistochemistry revealed that CD34+, TdT-positive cells were dispersed without significant clustering, while CD20+ cells exceeded CD34/TdT-positive cells in 24 of 25 cases. This multidisciplinary study demonstrates that hematogone-rich lymphoid proliferations exhibit a spectrum of B-lymphoid differentiation antigen expression with predominance of intermediate and mature B-lineage cells, heterogeneity of adhesion molecule expression, and nonclustered bone marrow architectural distribution.
Assuntos
Linfoma de Burkitt/imunologia , Linfoma de Burkitt/patologia , Moléculas de Adesão Celular/metabolismo , Adolescente , Medula Óssea/patologia , Linfoma de Burkitt/metabolismo , Divisão Celular , Criança , Pré-Escolar , Feminino , Citometria de Fluxo , Células-Tronco Hematopoéticas/patologia , Humanos , Imunofenotipagem , Lactente , Masculino , Células Tumorais Cultivadas/patologiaRESUMO
Early detection of relapse in children with acute lymphoblastic leukemia (ALL), as well as distinction of leukemic blasts from hematogones, can be difficult by morphologic examination alone. Using CD34 and terminal deoxynucleotidyl transferase (TdT) immunoperoxidase stains, we studied specimens from 25 children with ALL in morphologic remission to determine if we could identify children at risk of relapse. We studied morphologic remission bone marrow specimens from 9 patients who experienced relapse during the subsequent 6 months and 16 children who remained in complete remission, including 10 specimens with increased numbers of hematogones. Despite morphologic remission, clusters of more than 5 CD34+ and/or TdT-positive cells were identified before overt relapse in 6 of 9 cases of relapse, but were noted in only 1 of 10 specimens from children in continuous complete remission and none of 10 specimens with increased numbers of hematogones. Clusters of CD34+ or TdT-positive cells can identify individual patients at risk for imminent relapse. Hematogones may be differentiated from lymphoblasts by this method.
Assuntos
Antígenos CD34 , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais , Recidiva Local de Neoplasia/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Adolescente , Medula Óssea/patologia , Contagem de Células , Criança , Pré-Escolar , DNA Nucleotidilexotransferase/análise , Feminino , Células-Tronco Hematopoéticas/patologia , Humanos , Técnicas Imunoenzimáticas , Lactente , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Indução de Remissão , Estudos RetrospectivosRESUMO
BACKGROUND: Rhabdomyosarcoma is an aggressive tumor that is rarely found in pregnancy, and is usually treated with multiagent chemotherapy. Chemotherapy given during pregnancy is associated with several maternal-fetal complications, including risks for mutagenicity, myelosuppression, and fetal death. CASE: An 18-year-old woman had stage III facial rhabdomyosarcoma diagnosed early in the third trimester. She achieved clinical remission with multiagent chemotherapy given during pregnancy, with no fetal complications. CONCLUSION: Invasive rhabdomyosarcoma is biologically predisposed to metastasize, and in the absence of effective chemotherapy, most patients will develop sites of distant recurrence. Chemotherapy plays an important role as frontline treatment in pregnant women with rhabdomyosarcoma.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias dos Seios Paranasais/tratamento farmacológico , Complicações Neoplásicas na Gravidez/tratamento farmacológico , Rabdomiossarcoma Alveolar/tratamento farmacológico , Adolescente , Antibióticos Antineoplásicos/administração & dosagem , Antineoplásicos Alquilantes/administração & dosagem , Antineoplásicos Fitogênicos/administração & dosagem , Ciclofosfamida/administração & dosagem , Dactinomicina/administração & dosagem , Feminino , Humanos , Imageamento por Ressonância Magnética , Estadiamento de Neoplasias , Gravidez , Indução de Remissão , Vincristina/administração & dosagemRESUMO
We evaluated the analgesic efficacy of EMLA cream after repeated bone marrow aspirations or lumbar punctures (LPs) in children with cancer, and compared the ratings among patients, their parents, physicians, and nurses. Data from LPs were analyzed at the last procedure without EMLA (T1) and the first and last procedures with EMLA (T2 and T3). Friedman's nonparametric analysis of variance was used for statistical analysis. A total of 272 procedures in 29 children were analyzed. For 179 procedures without EMLA, physicians rated pain lower than other raters, and for the 93 with EMLA physicians rated pain less than the children. Children rated pain at T2 lower than at T1 or T3. Physicians rated pain at T2 less than at T3. Both children and physicians rated pain at T3 as not different from that at T1. No differences were noted at these time points for other raters in LP distress ratings, or in bone marrow aspiration pain or distress ratings. Thus EMLA was associated with decreased pain ratings for LPs, but this effect was not sustainable with repeated procedures. The cream alone should not be relied on to control pain of bone marrow aspiration or repeated LPs in children. Physicians underestimated pain, which may have implications for undertreatment in this patient population.
Assuntos
Anestésicos Locais/uso terapêutico , Lidocaína/uso terapêutico , Neoplasias/complicações , Dor/prevenção & controle , Prilocaína/uso terapêutico , Punção Espinal/efeitos adversos , Adolescente , Anestésicos Locais/administração & dosagem , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Lidocaína/administração & dosagem , Combinação Lidocaína e Prilocaína , Masculino , Variações Dependentes do Observador , Dor/etiologia , Medição da Dor , Prilocaína/administração & dosagemRESUMO
This work reports the tumoricidal effects of a novel investigational humanized anti-CD19 monoclonal antibody (Medi-551). An a-fucosylated antibody with increased affinity for human FcγRIIIA, Medi-551 is shown to mediate both antibody-dependent cellular cytotoxicity (ADCC) and antibody-dependent cellular phagocytosis (ADCP). Medi-551/CD19 complexes internalize slowly (>5 h) and thus remain accessible to effector cells for prolonged periods. We evaluated in vitro ADCC and ADCP activities of primary human natural killer (NK) cells and macrophages against precursor-B (pre-B) acute lymphoblastic leukemia (ALL) cell lines and pediatric patient blasts. Fluorescent imaging studies document immunological synapses formed between anti-CD19-bound target leukemia cells and effector cells and capture the kinetics of both NK-mediated killing and macrophage phagocytosis. Genetic polymorphisms in FcγRIIIA-158F/V modulate in vitro activities of effector cells, with FcγRIIIA-158V homozygotes or heterozygotes showing the strongest activity. Medi-551 treatment of severe combined immunodeficiency (SCID) mice engrafted with human pre-B cells led to prolonged animal survival and markedly reduced disease burden in blood, liver and bone marrow. These data show that anti-CD19 antibodies effectively recruit immune cells to pre-B ALL cells and support a move forward to early phase trials in this disease.
Assuntos
Anticorpos Monoclonais Humanizados/imunologia , Antígenos CD19/imunologia , Células Matadoras Naturais/imunologia , Leucemia de Células B/imunologia , Macrófagos/imunologia , Doença Aguda , Animais , Anticorpos Monoclonais Humanizados/metabolismo , Citotoxicidade Celular Dependente de Anticorpos , Linhagem Celular Tumoral , Feminino , Imunofluorescência , Fucose/metabolismo , Humanos , Masculino , Camundongos , Camundongos SCID , Transplante HeterólogoAssuntos
Proteínas Adaptadoras de Sinalização CARD/fisiologia , Sistema Nervoso Central/patologia , Guanilato Ciclase/fisiologia , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , Animais , Linhagem Celular Tumoral , Movimento Celular , Criança , Xenoenxertos , Humanos , Camundongos , Invasividade Neoplásica , Transdução GenéticaRESUMO
Gamma secretase inhibitors (GSIs) comprise a growing class of compounds that interfere with the membrane-bound Notch signaling protein and its downstream intra-nuclear transcriptional targets. As GSI-I (Z-LLNle-CHO) is also a derivative of a widely used proteosome inhibitor MG-132, we hypothesized that this compound might be active in precursor-B acute lymphoblastic leukemia (ALL) cell lines and patient samples. We found that GSI-I treatment of precursor-B ALL blasts induced apoptotic cell death within 18-24 h. With confirmation using RNA and protein analyses, GSI-I blocked nuclear accumulation of cleaved Notch1 and Notch2, and inhibited Notch targets Hey2 and Myc. Microarray analyses of 207 children with high-risk precursor-B ALL demonstrate that Notch pathway expression is a common feature of these neoplasms. However, microarray studies also implicated additional transcriptional targets in GSI-I-dependent cell death, including genes in the unfolded protein response, nuclear factor-κB and p53 pathways. Z-LLNle-CHO blocks both γ-secretase and proteosome activity, inducing more robust cell death in precursor-B ALL cells than either proteosome-selective or γ-secretase-selective inhibitors alone. Using Z-LLNle-CHO in a nonobese diabetes/severe combined immunodeficiency (NOD/SCID) precursor-B ALL xenograft model, we found that GSI-I alone delayed or prevented engraftment of B-lymphoblasts in 50% of the animals comprising the experimental group, suggesting that this compound is worthy of additional testing.
Assuntos
Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Proteínas de Neoplasias/antagonistas & inibidores , Oligopeptídeos/farmacologia , Leucemia-Linfoma Linfoblástico de Células Precursoras B/enzimologia , Inibidores de Proteases/farmacologia , Inibidores de Proteassoma , Receptores Notch/fisiologia , Secretases da Proteína Precursora do Amiloide/metabolismo , Animais , Antineoplásicos/uso terapêutico , Linfócitos B/efeitos dos fármacos , Linfócitos B/enzimologia , Linhagem Celular Tumoral/efeitos dos fármacos , Linhagem Celular Tumoral/enzimologia , Criança , Estudos de Coortes , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Proteínas de Neoplasias/efeitos dos fármacos , Proteínas de Neoplasias/metabolismo , Oligopeptídeos/uso terapêutico , Leucemia-Linfoma Linfoblástico de Células Precursoras B/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras B/patologia , Inibidores de Proteases/uso terapêutico , Complexo de Endopeptidases do Proteassoma/efeitos dos fármacos , RNA Mensageiro/metabolismo , RNA Neoplásico/metabolismo , Receptores Notch/genética , Risco , Organismos Livres de Patógenos Específicos , Transcrição Gênica/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Adulto JovemAssuntos
Linhagem da Célula , Resistencia a Medicamentos Antineoplásicos/genética , Histona-Lisina N-Metiltransferase/genética , Proteínas de Homeodomínio/genética , Proteína de Leucina Linfoide-Mieloide/genética , Recidiva Local de Neoplasia/genética , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Adolescente , Adulto , Criança , Pré-Escolar , Intervalo Livre de Doença , Feminino , Rearranjo Gênico , Humanos , Masculino , Recidiva Local de Neoplasia/mortalidade , Leucemia-Linfoma Linfoblástico de Células T Precursoras/mortalidade , Prognóstico , Estudos RetrospectivosAssuntos
Cromossomos Humanos Par 1/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Cromossomo Filadélfia , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Translocação Genética/genética , Antígenos CD/metabolismo , Antígenos de Neoplasias/metabolismo , Criança , Feminino , Humanos , Hibridização in Situ Fluorescente , Cariotipagem , Leucemia Mielogênica Crônica BCR-ABL Positiva/terapia , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapiaRESUMO
Ultrasonographic records of 75 children with sickle cell disease and hepatobiliary symptoms were reviewed. Seventeen had gallbladder sludge, nine with concurrent stones and eight with sludge alone. Because all the children eventually had gallstones, we recommend that elective cholecystectomy be performed on patients with gallbladder sludge.
Assuntos
Anemia Falciforme/complicações , Doenças da Vesícula Biliar/complicações , Doença da Hemoglobina SC/complicações , Criança , Colecistectomia , Colelitíase/complicações , Colelitíase/diagnóstico por imagem , Colelitíase/cirurgia , Estudos de Coortes , Procedimentos Cirúrgicos Eletivos , Feminino , Doenças da Vesícula Biliar/diagnóstico por imagem , Doenças da Vesícula Biliar/cirurgia , Humanos , Masculino , Estudos Retrospectivos , Fatores de Tempo , UltrassonografiaRESUMO
Interactions between erythropoietin (Epo) and its receptor (EpoR) are critical for the normal proliferation and differentiation of erythroid progenitor cells. EpoR is expressed in low numbers during early stages of erythroid maturation, while higher levels are expressed during later stages, suggesting that the expression of the EpoR gene is tightly regulated throughout erythropoiesis. We used the TF-1 erythroleukemia cell line to analyze the effects of various cytokines and reagents on the regulation of human EpoR gene expression. Human EpoR gene expression was significantly upregulated by IL-1 alpha and the protein inhibitor cycloheximide, but significantly downregulated by the calcium ionophore ionomycin and the phorbol ester PMA. These effects on EpoR gene expression were not due to changes in EpoR mRNA stability, suggesting that these agents directly affected EpoR gene transcription. The selective in vitro modification of EpoR expression by these agents highlights the complexity of human EpoR gene expression, and provides clues to its in vivo regulation.
Assuntos
Receptores da Eritropoetina/genética , Antígenos de Superfície/análise , Northern Blotting , Divisão Celular , Células Cultivadas , Cicloeximida/farmacologia , Eritropoetina/farmacologia , Humanos , Interleucina-1/farmacologia , Ionomicina/farmacologia , Ionóforos/farmacologia , Inibidores da Síntese de Proteínas/farmacologia , Acetato de Tetradecanoilforbol/farmacologia , Regulação para CimaRESUMO
BACKGROUND: The ex vivo survival of leukemic cells maintained on bone marrow stroma is an important tool for the investigation of cell survival and leukemogenesis. Currently, ex vivo survival of leukemic cell survival is measured by coculture on stromal cell monolayers. In these assays, we postulated that two important sources of error might be introduced through either variations in flow volume or in donor stromal cells. METHODS: A previously reported coculture assay that maintains leukemic cells on bone marrow stromal cells was employed. RESULTS: We identified two means of optimizing the coculture assay. First, biologically inert beads having well-characterized fluorescent properties were added to each sample to mathematically adjust for flow-based variations in volume acquisition. The inclusion of fluorescent beads to the basic stromal cell assay showed a significantly lower coefficient of variation as compared to samples analyzed without beads or manually counted using a hemacytometer. Second, in order to minimize variability in bone marrow hematopoietic function between donors, an adherent stromal cell line known to support hematopoiesis (HS-5) was used. When normal human donor stromal cells were used, variability in the survival of leukemic cells was observed on stromal cells derived from different donors. In contrast, statistically significant variability in survival of leukemic cells was not seen on HS-5 monolayers. Finally, we demonstrate that patient-derived leukemic samples may be examined for cell survival using these modifications. CONCLUSIONS: The novel use of fluorescent beads and a hematopoietic-supportive stromal cell line together makes the quantification of stroma-supported cell survival more reproducible, accurate, and amenable to patient-derived samples. These improvements in flow cytometry-based cell quantification are an important step in establishing a role for stromal cell assays in the study of leukemia biology and therapy.
Assuntos
Células da Medula Óssea/citologia , Técnicas de Cultura de Células/métodos , Citometria de Fluxo/métodos , Células Estromais/citologia , Linhagem Celular Transformada/citologia , Sobrevivência Celular/fisiologia , Citometria de Fluxo/normas , Corantes Fluorescentes , Hematopoese/fisiologia , Humanos , Leucemia-Linfoma de Células T do Adulto , Microesferas , Reprodutibilidade dos TestesRESUMO
Ki-1 lymphoma is a rare, large-cell anaplastic non-Hodgkin's lymphoma that most commonly affects older children and young adults. Presentation usually occurs as a localized infiltration of the skin and lymph nodes. We report an unusual case of childhood Ki-1 lymphoma that presented as a buttock mass in an eight-year-old girl, Pathologic evaluation revealed the characteristic lymphoma cells expressing Ki-1 antigen (CD-30), HLA-DR, interleukin 2 (CD-25), T-cell gene rearrangement, and the cytogenetic karyotype t(2;5). The patient is in complete remission following treatment with combination chemotherapy. This report broadens the clinical spectrum associated with Ki-1 lymphomas and illustrates the importance of combining routine pathologic examination with other specialized diagnostic techniques in the evaluation of childhood soft-tissue masses.
Assuntos
Nádegas , Linfoma Difuso de Grandes Células B/patologia , Neoplasias de Tecidos Moles/patologia , Aneuploidia , Antígenos CD/análise , Antígenos de Neoplasias/análise , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/análise , Bleomicina/administração & dosagem , Nádegas/lesões , Criança , Ciclofosfamida/administração & dosagem , Citarabina/administração & dosagem , Doxorrubicina/administração & dosagem , Etoposídeo/administração & dosagem , Feminino , Rearranjo Gênico do Linfócito T , Humanos , Antígeno Ki-1 , Metástase Linfática , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/imunologia , Metotrexato/administração & dosagem , Prednisona/administração & dosagem , Indução de Remissão , Neoplasias de Tecidos Moles/tratamento farmacológico , Neoplasias de Tecidos Moles/genética , Neoplasias de Tecidos Moles/imunologia , Linfócitos T Auxiliares-Indutores/patologia , Vincristina/administração & dosagemRESUMO
PURPOSE: We report a case of an isolated optic nerve relapse 3.5 years after diagnosis of hyperdiploid acute lymphoblastic leukemia (ALL) in a 6-year-old boy who had been off treatment for 3 months. The use of interphase fluorescence in situ hybridization (FISH) for clonal identification of chromosome abnormalities is described. PATIENT AND METHODS: An asymptomatic lesion over the right optic nerve head was identified on routine funduscopic exam. Fine needle aspiration of the optic nerve infiltrate provided tissue for morphologic, immunohistochemical, and FISH analyses. RESULTS: FISH showed similar but not identical chromosome makeup of the leukemic blasts at the time of relapse as compared to tissue samples obtained at the time of diagnosis. CONCLUSION: Despite antimetabolite therapy, hyperdiploid ALL can rarely recur isolated to an optic nerve. FISH is a useful adjunct for confirming relapse when low numbers of white blood cells are obtained with fine needle aspiration.