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1.
Artigo em Inglês | MEDLINE | ID: mdl-38418356

RESUMO

OBJECTIVE: Analysis of rechallenge with nivolumab as 5th-line therapy for locally and nodally failed laryngeal squamous cell carcinoma following conventional therapeutic modalities: radiotherapy, surgery and chemotherapy. OBSERVATION: A 70-year-old male, with local and nodal progression of laryngeal squamous cell carcinoma after treatment with chemoradiotherapy and surgery, was initially treated for recurrence with carboplatin, 5-fluorouracile (FU) and cetuximab, followed by second-line nivolumab, and then two lines of conventional chemotherapy with paclitaxel and cetuximab followed by carboplatin and cetuximab. He underwent rechallenge with nivolumab in 5th line, achieving 12months' response, ongoing at the time of writing, and 42.5months' survival since initiation of exclusive systemic management after failure of conventional treatment. CONCLUSION: This case report highlights the benefit of nivolumab rechallenge in 5th line following previous failure as stand-alone therapy in 2nd line for a patient with laryngeal squamous cell carcinoma locally and nodally uncontrolled after conventional treatment. Clinical trials evaluating the efficacy of this approach are necessary to assess its contribution, as it is currently not a standard therapeutic option.

2.
Eur Ann Otorhinolaryngol Head Neck Dis ; 140(5): 221-225, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37321906

RESUMO

PURPOSE: To evaluate the consequences of treatment refusal in total laryngectomy (TL) candidates with T3-4M0 endolaryngeal squamous cell carcinoma (SCC). MATERIALS AND METHODS: A retrospective observational study was conducted in an inception cohort of 576 isolated T3-4M0 endolaryngeal SCC candidates for TL consecutively managed between 1970 and 2019 in a French university teaching hospital. The main endpoint was survival time and cause of death in 2 groups. Group A, 4.5% of the cohort, consisted of 26 patients who declined any laryngeal treatment. Group B consisted of 550 patients who accepted TL. Accessory endpoints were causes of TL refusal and associated variables. The STROBE guideline was applied. The significance threshold was set at P<0.005. RESULTS: One-and 3-year actuarial survival estimates increased significantly (P<0.0001) from 39% and 15% in group A, to 83% and 63% in group B, respectively. In group A, 92% of causes of death implicated index SCC progression, whereas in group B intercurrent disease, metachronous second primary, locoregional and/or metastatic SCC progression and postoperative complications accounted for 37%, 31%, 29%, and 2%, respectively. The actuarial survival estimates within group A increased significantly (P=0.0003) from 0% at 1-year in patients managed with isolated supportive care to 56% in patients managed with chemotherapy (reaching 0% at 5years). Reasons for TL refusal were fear of surgery, refusal of tracheostoma, loss of physiologic phonation, and certain comorbidities. Age and chronologic period correlated significantly with TL refusal. Median age decreased (P<0.001) from 69years in group A to 58 years in group B. Percentage TL refusal increased (P<0.0001) from 2% to 11% before and after start 1990, respectively. CONCLUSION: The current study determined loss of survival with refusal of any laryngeal treatment including TL, noted benefit of chemotherapy associated to supportive care, and discussed the possible contribution of immunotherapy.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Laríngeas , Laringe , Idoso , Humanos , Carcinoma de Células Escamosas/cirurgia , Neoplasias Laríngeas/cirurgia , Laringectomia , Laringe/patologia , Estadiamento de Neoplasias , Estudos Retrospectivos , Resultado do Tratamento , Recusa do Paciente ao Tratamento , Pessoa de Meia-Idade
3.
Leukemia ; 31(3): 565-572, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27694926

RESUMO

Pediatric acute myeloid leukemia (AML) is a rare disease whose prognosis is highly variable according to factors such as chromosomal abnormalities. Recurrent genomic rearrangements are detected in half of pediatric AML by karyotype. NUcleoPorin 98 (NUP98) gene is rearranged with 31 different fusion partner genes. These rearrangements are frequently undetected by conventional cytogenetics, as the NUP98 gene is located at the end of the chromosome 11 short arm (11p15). By screening a series of 574 pediatric AML, we detected a NUP98 rearrangement in 22 cases (3.8%), a frequency similar to CBFB-MYH11 fusion gene (4.0%). The most frequent NUP98 fusion gene partner is NSD1. These cases are homogeneous regarding their biological and clinical characteristics, and associated with bad prognosis only improved by bone marrow transplantation. We detailed the biological characteristics of these AML by exome sequencing which demonstrated few recurrent mutations (FLT3 ITD, WT1, CEBPA, NBPF14, BCR and ODF1). The analysis of the clonal structure in these cases suggests that the mutation order in the NUP98-rearranged pediatric AML begins with the NUP98 rearrangement leading to epigenetic dysregulations then followed by mutations of critical hematopoietic transcription factors and finally, activation of the FLT3 signaling pathway.


Assuntos
Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/genética , Complexo de Proteínas Formadoras de Poros Nucleares/genética , Translocação Genética , Alelos , Biomarcadores Tumorais , Proteínas Estimuladoras de Ligação a CCAAT/genética , Criança , Pré-Escolar , Epigênese Genética , Exoma , Feminino , Regulação Leucêmica da Expressão Gênica , Frequência do Gene , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Hibridização in Situ Fluorescente , Lactente , Recém-Nascido , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/mortalidade , Masculino , Mutação , Proteínas de Fusão Oncogênica/genética , Prognóstico , Transdução de Sinais , Proteínas WT1/genética , Tirosina Quinase 3 Semelhante a fms/metabolismo
6.
J Colloid Interface Sci ; 388(1): 130-6, 2012 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-23000208

RESUMO

The formation of a new hybrid material based on titanium dioxide as inorganic support and containing an iron organochelator (ICL670) is described. An organophosphorous coupling agent was used to graft the organic molecule on the oxide surface. The attachment of the organic substrate was well-confirmed by FTIR (DRIFT), solid-state (31)P and (13)C CPMAS NMR, thermal analysis and the integrity of the structural and morphological parameters were verified using XRD and TEM analyses. The interaction between the material and dissolved iron(III) was also investigated through potentiometric measurements and demonstrated the interest of this new non-siliceous based hybrid material. The obtained linear evolution of the open circuit potential from 10(-2) to 10(-6) mol L(-1) can be used for the analytical detection of iron(III).


Assuntos
Ferro/análise , Titânio/química , Espectroscopia de Ressonância Magnética , Microscopia Eletrônica de Transmissão , Potenciometria , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Difração de Raios X
8.
Leukemia ; 23(1): 85-94, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18818702

RESUMO

The t(8;16)(p11;p13) is a rare translocation involved in de novo and therapy-related myelomonocytic and monocytic acute leukemia. It fuses two genes encoding histone acetyltransferases (HATs), MYST3 located at 8p11 to CREBBP located at 16p13. Variant translocations involve other HAT-encoding genes such as EP300, MYST4, NCOA2 or NCOA3. MYST3-linked acute myeloid leukemias (AMLs) share specific clinical and biological features and a poor prognosis. Because of its rarity, the molecular biology of MYST3-linked AMLs remains poorly understood. We have established the genome and gene expression profiles of a multicentric series of 61 M4/M5 AMLs including 18 MYST3-linked AMLs by using array comparative genome hybridization (aCGH) (n=52) and DNA microarrays (n=44), respectively. We show that M4/5 AMLs have a variety of rare genomic alterations. One alteration, a gain of the MYB locus, was found recurrently and only in the MYST3-linked AMLs (7/18 vs 0/34). MYST3-AMLs have also a specific a gene expression profile, which includes overexpression of MYB, CD4 and HOXA genes. These features, reminiscent of T-cell acute lymphoid leukemia (ALL), suggest the targeting of a common T-myeloid progenitor.


Assuntos
Perfilação da Expressão Gênica/métodos , Genes myb/genética , Histona Acetiltransferases/genética , Leucemia Mielomonocítica Aguda/genética , Antígenos CD4/genética , Hibridização Genômica Comparativa , Regulação Neoplásica da Expressão Gênica , Genoma Humano , Proteínas de Homeodomínio/genética , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas Proto-Oncogênicas c-myb/genética
9.
Ann Fr Anesth Reanim ; 27(10): e53-7, 2008 Oct.
Artigo em Francês | MEDLINE | ID: mdl-18951753

RESUMO

In the literature, the distinction between medical errors, adverse events, complications of care and other terms related to patient safety is not well-established. Accordingly these terms are commonly interchangeable. There is consensus that common terminology and classification scheme (taxonomy) with standardisation of patient safety data would facilitate improvement in incidents reporting, tracking and analysis. In this report medical errors, adverse events, safety indicators and other terms such as preventability and safety practices are defined and submitted to the expert panel rating.


Assuntos
Unidades de Terapia Intensiva/normas , Erros Médicos/classificação , Guias de Prática Clínica como Assunto , Indicadores de Qualidade em Assistência à Saúde/classificação , Gestão de Riscos/normas , Gestão da Segurança/normas , Terminologia como Assunto , França , Humanos , Erros Médicos/prevenção & controle , Garantia da Qualidade dos Cuidados de Saúde/organização & administração , Garantia da Qualidade dos Cuidados de Saúde/normas , Reprodutibilidade dos Testes
11.
Leukemia ; 22(8): 1567-75, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18528428

RESUMO

Thirty cases of acute myeloid leukaemia (AML) with MYST histone acetyltransferase 3 (MYST3) rearrangement were collected in a retrospective study from 14 centres in France and Belgium. The mean age at diagnosis was 59.4 years and 67% of the patients were females. Most cases (77%) were secondary to solid cancer (57%), haematological malignancy (35%) or both (8%), and appeared 25 months after the primary disease. Clinically, cutaneous localization and disseminated intravascular coagulation were present in 30 and 40% of the cases, respectively. AMLs were myelomonocytic (7%) or monocytic (93%), with erythrophagocytosis (75%) and cytoplasmic vacuoles (75%). Immunophenotype showed no particularity compared with monocytic leukaemia without MYST3 abnormality. Twenty-eight cases carried t(8;16)(p11;p13) with MYST3-CREBBP fusion, one case carried a variant t(8;22)(p11;q13) and one case carried a t(8;19)(p11;q13). Type I (MYST3 exon 16-CREBBP exon 3) was the most frequent MYST3-CREBBP fusion transcript (65%). MYST3 rearrangement was associated with a poor prognosis, as 50% of patients deceased during the first 10 months. All those particular clinical, cytologic, cytogenetic, molecular and prognostic characteristics of AML with MYST3 rearrangement may have allowed an individualization into the World Health Organization classification.


Assuntos
Cromossomos Humanos Par 8 , Rearranjo Gênico , Histona Acetiltransferases/genética , Leucemia Mieloide Aguda/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Sequência de Bases , Primers do DNA , Feminino , Humanos , Imunofenotipagem , Hibridização in Situ Fluorescente , Cariotipagem , Leucemia Mieloide Aguda/imunologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Reação em Cadeia da Polimerase Via Transcriptase Reversa
12.
Leukemia ; 22(1): 132-7, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17928884

RESUMO

A series of 38 patients with acute myeloblastic leukemia (AML) with 49 or more chromosomes and without structural abnormalities was selected within the Groupe Francophone de Cytogénétique Hématologique (GFCH) to better define their characteristics. The median age of the patients was 65 years, and all FAB subtypes were represented. Although all chromosomes were gained, some seems to prevail: chromosome 8 (68%), 21 (47%), 19 (37%), and 13 and 14 (34% each). Since MLL rearrangement leads patients in a group with an unfavorable prognosis, search for cryptic rearrangements of MLL was performed in 34 patients and showed abnormalities in 5 (15%). When we applied the most frequent definition of complex karyotypes (three or more abnormalities), all patients with high hyperdiploid AML fall in the unfavorable category. Among the 18 patients without MLL rearrangement receiving an induction therapy, 16 (89%) reached CR and 6 (33%) were still alive after a 31-month median follow-up (14-61 months). Although this study was retrospective, these results suggest that high hyperdiploid AML without chromosome rearrangement seems to be a subgroup of uncommon AML (less than 1%), and may be better classified in the intermediate prognostic group.


Assuntos
Aberrações Cromossômicas , Cromossomos Humanos/genética , Leucemia Mieloide/genética , Ploidias , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Rearranjo Gênico , Histona-Lisina N-Metiltransferase , Humanos , Hibridização in Situ Fluorescente , Cariotipagem , Leucemia Mieloide/tratamento farmacológico , Leucemia Mieloide/epidemiologia , Masculino , Pessoa de Meia-Idade , Proteína de Leucina Linfoide-Mieloide/genética , Prognóstico , Estudos Prospectivos , Estudos Retrospectivos
13.
Pathol Biol (Paris) ; 55(1): 59-72, 2007 Feb.
Artigo em Francês | MEDLINE | ID: mdl-16690228

RESUMO

A cytological, immunophenotypical and cytogenetical study of 136 chronic B-cell proliferations (93 CLL, 43 B-cell lymphomas) was led in order to precise diagnosis and to characterize and appreciate chromosomal rearrangements. In this series, mainly selected on blood lymphocytosis criteria, B-CLL were twice more frequent than small B-cell lymphomas. Probes used revealed cryptic abnormalities, which remained unknown by conventional cytogenetics (CC). The frequency of clonal abnormalities (CC and FISH) was 74.8% for this series, with 74.4% for lymphomas and 75.3% for CLL, mainly of Binet stage A (69 A, 13 B, 1 C, 10 unspecified). Proportion was 88.4% in A stages and 84.6% in B stages. In CLL, 13q14 cryptic deletions and translocations were widely majority, 14q32 translocations and trisomy 12 being predominant in lymphoma series. Interphase FISH study of non-clonal metaphasic abnormalities with locus-specific probes often revealed unrecognised clones.


Assuntos
Aberrações Cromossômicas , Cromossomos Humanos/genética , Leucemia Linfocítica Crônica de Células B/genética , Linfoma de Células B/genética , Aneuploidia , Cromossomos Humanos/ultraestrutura , Cromossomos Humanos Par 13/genética , Cromossomos Humanos Par 13/ultraestrutura , Células Clonais/patologia , Estudos de Coortes , Feminino , Humanos , Imunofenotipagem , Hibridização in Situ Fluorescente , Cariotipagem , Leucemia Linfocítica Crônica de Células B/patologia , Linfoma de Células B/patologia , Transtornos Linfoproliferativos/genética , Masculino , Estadiamento de Neoplasias , Deleção de Sequência
14.
Leukemia ; 21(1): 121-8, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17039236

RESUMO

Recently, we and others described a new chromosomal rearrangement, that is, inv(7)(p15q34) and t(7;7)(p15;q34) involving the T-cell receptor beta (TCRbeta) (7q34) and the HOXA gene locus (7p15) in 5% of T-cell acute lymphoblastic leukemia (T-ALL) patients leading to transcriptional activation of especially HOXA10. To further address the clinical, immunophenotypical and molecular genetic findings of this chromosomal aberration, we studied 330 additional T-ALLs. This revealed TCRbeta-HOXA rearrangements in five additional patients, which brings the total to 14 cases in 424 patients (3.3%). Real-time quantitative PCR analysis for HOXA10 gene expression was performed in 170 T-ALL patients and detected HOXA10 overexpression in 25.2% of cases including all the cases with a TCRbeta-HOXA rearrangement (8.2%). In contrast, expression of the short HOXA10 transcript, HOXA10b, was almost exclusively found in the TCRbeta-HOXA rearranged cases, suggesting a specific role for the HOXA10b short transcript in TCRbeta-HOXA-mediated oncogenesis. Other molecular and/or cytogenetic aberrations frequently found in subtypes of T-ALL (SIL-TAL1, CALM-AF10, HOX11, HOX11L2) were not detected in the TCRbeta-HOXA rearranged cases except for deletion 9p21 and NOTCH1 activating mutations, which were present in 64 and 67%, respectively. In conclusion, this study defines TCRbeta-HOXA rearranged T-ALLs as a distinct cytogenetic subgroup by clinical, immunophenotypical and molecular genetic characteristics.


Assuntos
Proteínas de Homeodomínio/genética , Leucemia-Linfoma de Células T do Adulto/genética , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Adolescente , Adulto , Criança , Deleção Cromossômica , Inversão Cromossômica , Feminino , Rearranjo Gênico do Linfócito T , Proteínas Homeobox A10 , Humanos , Imunofenotipagem , Leucemia-Linfoma de Células T do Adulto/patologia , Leucemia-Linfoma de Células T do Adulto/fisiopatologia , Masculino , Pessoa de Meia-Idade , Receptor Notch1/genética , Ativação Transcricional , Translocação Genética
16.
Leukemia ; 18(8): 1340-6, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15190256

RESUMO

Imatinib mesylate (Gleevec), an inhibitor of the BCR-ABL tyrosine kinase, was introduced recently into the therapy of chronic myeloid leukemia (CML). Several cases of emergence of clonal chromosomal abnormalities after therapy with imatinib have been reported, but their incidence, etiology and prognosis remain to be clarified. We report here a large series of 34 CML patients treated with imatinib who developed Philadelphia (Ph)-negative clones. Among 1001 patients with Ph-positive CML treated with imatinib, 34 (3.4%) developed clonal chromosomal abnormalities in Ph-negative cells. Three patients were treated with imatinib up-front. The most common cytogenetic abnormalities were trisomy 8 and monosomy 7 in twelve and seven patients, respectively. In 15 patients, fluorescent in situ hybridization with specific probes was performed in materials archived before the initiation of imatinib. The Ph-negative clone was related to previous therapy in three patients, and represented a minor pre-existing clone that expanded after the eradication of Ph-positive cells with imatinib in two others. However, in 11 patients, the new clonal chromosomal abnormalities were not detected and imatinib may have had a direct effect. No myelodysplasia was found in our cohort. With a median follow-up of 24 months, one patient showed CML acceleration and two relapsed.


Assuntos
Aberrações Cromossômicas , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mieloide Crônica Atípica BCR-ABL Negativa/genética , Leucemia Mieloide Crônica Atípica BCR-ABL Negativa/patologia , Piperazinas/uso terapêutico , Pirimidinas/uso terapêutico , Adulto , Idoso , Aneuploidia , Benzamidas , Cromossomos Humanos Par 7 , Cromossomos Humanos Par 8 , Células Clonais/patologia , Feminino , Humanos , Mesilato de Imatinib , Incidência , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos
17.
Pathol Biol (Paris) ; 51(6): 356-65, 2003 Aug.
Artigo em Francês | MEDLINE | ID: mdl-12927893

RESUMO

Secondary leukemias group essentially together myelodysplastic syndromes and acute leukemias, therapy-related (chemo- or radio-), or consecutive to environmental factors. It's now proven that some recurrent abnormalities are associated with effects of therapeutic agents, as -5/del(5q), -7/del(7q) linked to alkylating agents, or 11q23 and 21q22 abnormalities linked to inhibitors of Topoisomerase II. Even if important differences between secondary and "de novo" forms exist, the discrimination between these 2 categories is not always obvious: many common chromosomal abnormalities, "de novo" leukemias in older patients having characteristics close to those of postalkylating leukemias, neonatal forms possibly secondary to maternal affect. Recent studies identified some others chromosomal abnormalities in the secondary leukemias and confirmed the poor prognosis of these hemopathies. This review sums up criterions, circumstances and cytogenetic abnormalities.


Assuntos
Aberrações Cromossômicas , Leucemia/etiologia , Leucemia/genética , Síndromes Mielodisplásicas/etiologia , Síndromes Mielodisplásicas/genética , Antineoplásicos Alquilantes/efeitos adversos , Inibidores Enzimáticos/efeitos adversos , Deleção de Genes , Humanos , Prognóstico , Radiação Ionizante , Inibidores da Topoisomerase II , Translocação Genética
18.
Ann Intern Med ; 132(8): 621-30, 2000 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-10766680

RESUMO

BACKGROUND: Optimal management of patients who are clinically suspected of having ventilator-associated pneumonia remains open to debate. OBJECTIVE: To evaluate the effect on clinical outcome and antibiotic use of two strategies to diagnose ventilator-associated pneumonia and select initial treatment for this condition. DESIGN: Multicenter, randomized, uncontrolled trial. SETTING: 31 intensive care units in France. PATIENTS: 413 patients suspected of having ventilator-associated pneumonia. INTERVENTION: The invasive management strategy was based on direct examination of bronchoscopic protected specimen brush samples or bronchoalveolar lavage samples and their quantitative cultures. The noninvasive ("clinical") management strategy was based on clinical criteria, isolation of microorganisms by nonquantitative analysis of endotracheal aspirates, and clinical practice guidelines. MEASUREMENTS: Death from any cause, quantification of organ failure, and antibiotic use at 14 and 28 days. RESULTS: Compared with patients who received clinical management, patients who received invasive management had reduced mortality at day 14 (16.2% and 25.8%; difference, -9.6 percentage points [95% CI, -17.4 to -1.8 percentage points]; P = 0.022), decreased mean Sepsis-related Organ Failure Assessment scores at day 3 (6.1+/-4.0 and 7.0+/-4.3; P = 0.033) and day 7 (4.9+/-4.0 and 5.8+/-4.4; P = 0.043), and decreased antibiotic use (mean number of antibiotic-free days, 5.0+/-5.1 and 2.2+/-3.5; P < 0.001). At 28 days, the invasive management group had significantly more antibiotic-free days (11.5+/-9.0 compared with 7.5+/-7.6; P < 0.001), and only multivariate analysis showed a significant difference in mortality (hazard ratio, 1.54 [CI, 1.10 to 2.16]; P = 0.01). CONCLUSIONS: Compared with a noninvasive management strategy, an invasive management strategy was significantly associated with fewer deaths at 14 days, earlier attenuation of organ dysfunction, and less antibiotic use in patients suspected of having ventilator-associated pneumonia.


Assuntos
Antibacterianos/uso terapêutico , Infecção Hospitalar/diagnóstico , Infecção Hospitalar/tratamento farmacológico , Pneumonia Bacteriana/diagnóstico , Pneumonia Bacteriana/tratamento farmacológico , Respiração Artificial/efeitos adversos , Lavagem Broncoalveolar , Broncoscopia , Infecção Hospitalar/etiologia , Interpretação Estatística de Dados , Humanos , Mortalidade , Insuficiência de Múltiplos Órgãos/etiologia , Pneumonia Bacteriana/etiologia , Resultado do Tratamento
19.
Hybridoma ; 19(1): 33-41, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10768839

RESUMO

Bispecific antibodies with specificity for tumor antigen and CD3 have been shown to redirect the cytotoxicity of T cells against relevant tumor. Our objective was to generate single-chain bispecific antibodies (bsSCA) that could retarget mouse cytotoxic T lymphocytes (CTL) to destroy human ovarian carcinoma in a xenogeneic setting. A bsSCA, 2C11 x B43.13, was constructed by genetic engineering and expressed in mammalian cells. Molecular characteristics, binding properties, and ability to retarget CTL were studied. Western blot analysis showed that the product is a 65-kDa protein. Purification of antibodies could be done by single-step affinity chromatography using protein L-agarose with an unoptimized yield of 200 microg/L. BsSCA 2C11 x B43.13 was capable of binding to mouse CD3 and human CA125 as detected by FACS analysis of EL4 and OVCAR Nu3H2 cells, respectively. It could also bridge activated splenic T cells and human ovarian carcinoma as demonstrated by a bridge FACS assay. Redirected mouse CTL could mediate human target cell lysis in a 20-h 51Cr release assay despite that they are xenogeneic. Prolonged incubation of redirected CTL and tumor targets resulted in a dramatic reduction in tumor cell number. CD28 co-stimulation enhanced redirected CTL function in both types of assays. BsSCA 2C11 x B43.13 thus can be used as a preclinical immunotherapeutic model for human ovarian cancer in a xenogeneic setting.


Assuntos
Anticorpos Biespecíficos/isolamento & purificação , Neoplasias Ovarianas/imunologia , Linfócitos T/imunologia , Animais , Anticorpos Biespecíficos/biossíntese , Anticorpos Biespecíficos/genética , Anticorpos Biespecíficos/toxicidade , Anticorpos Monoclonais/biossíntese , Anticorpos Monoclonais/genética , Anticorpos Monoclonais Murinos , Antígeno Ca-125/imunologia , Complexo CD3/imunologia , Técnicas de Cocultura , Citotoxicidade Imunológica , Feminino , Inibidores do Crescimento/biossíntese , Inibidores do Crescimento/genética , Inibidores do Crescimento/isolamento & purificação , Inibidores do Crescimento/toxicidade , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/terapia , Células Tumorais Cultivadas
20.
Biotechnol Bioeng ; 63(5): 516-28, 1999 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-10397808

RESUMO

It is now well documented that apoptosis represents the prevalent mode of death in lymphoid cultures and occurs spontaneously in late-exponential phase of batch cultures following nutrient exhaustion. In an attempt to enhance the cell survival of these cell lines, we have initially engineered nonproducing NS/0 myeloma cells with a vector expressing the adenoviral E1B-19K protein. NS/0 cells transfected with E1B-19K were found to be more resistant to apoptosis occurring in the late phase of batch culture and under stressful conditions such as cultivation in glutamine-free medium or following heat shock. In this study, we have characterised a number of NS/0 subclones constitutively expressing different levels of E1B-19K, as well as several subclones in which the expression of E1B-19K was regulated by a tetracycline-controllable gene switch. We have found that a threshold E1B-19K level was required in order to achieve protection against apoptosis. The extent of resistance against cell death induced by nutrient deprivation in glutamine-free medium and in the late phase of batch cultures correlated with the level of E1B-19K expression up to an optimal level where further increases in E1B-19K levels did not result in significant additional protection. To assess the effects of E1B-19K on antibody productivity, an apoptosis-resistant NS/0 clone was then transfected with a chimeric antibody construct. Despite their improved viability, the antibody productivity of E1B-19K clones in batch culture was not significantly improved. Moreover, while the use of E1B-19K considerably delayed cell death, cells eventually died by apoptosis. Surprisingly, E1B-19K had no beneficial effect on the efficiency of fusion of NS/0 myelomas and splenocytes for the generation of hybridoma cells. Furthermore, the resulting hybridomas, although expressing E1B-19K at levels comparable to the myeloma parent, were no longer resistant to apoptosis. This indicates that the ability of E1B-19K to prevent apoptosis is not only dose-dependent but also seems to be cell-type dependent.


Assuntos
Proteínas E1B de Adenovirus/genética , Apoptose/genética , Mieloma Múltiplo/patologia , Anticorpos Monoclonais/genética , Fusão Celular , Células Clonais , Meios de Cultura , Vetores Genéticos , Glutamina , Resposta ao Choque Térmico , Humanos , Hibridomas , Mieloma Múltiplo/genética , Baço/citologia , Transfecção , Células Tumorais Cultivadas
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