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1.
Leukemia ; 18(3): 616-23, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14749704

RESUMO

Survivin is a member of the inhibitor of apoptosis protein (IAP) family and functions both as an apoptosis inhibitor and a regulator of cell division. Survivin overexpression is common in many human tumors and correlates with survival in large cell non-Hodgkin's lymphoma. To evaluate this molecule as a potential therapeutic target in large-cell lymphoma, we evaluated the effect of survivin inhibition both in vitro and in vivo. Using an antisense oligonucleotide (ASO) approach, cell growth was significantly inhibited in the DoHH2, RL and HT lymphoma cell lines. In a lymphoma xenograft model, the development of tumors as well as the growth of established tumors was inhibited in the survivin ASO-treated mice compared to controls. To assess the efficacy of the survivin ASO in combination with other biological agents, we combined the survivin ASO with an anti-CD20 monoclonal antibody, rituximab. The effect of survivin ASO and rituximab in combination was additive in vitro. In vivo, however, suppression of tumor growth with the combination was not significantly superior to controls. We conclude that inhibition of survivin expression is an attractive therapeutic strategy in aggressive non-Hodgkin's lymphomas, and that combining survivin ASO with rituximab may enhance the efficacy of this approach.


Assuntos
Regulação Neoplásica da Expressão Gênica , Linfoma não Hodgkin/patologia , Proteínas Associadas aos Microtúbulos/antagonistas & inibidores , Animais , Apoptose/efeitos dos fármacos , Caspase 3 , Caspases/metabolismo , Divisão Celular/efeitos dos fármacos , Humanos , Proteínas Inibidoras de Apoptose , Linfoma não Hodgkin/genética , Linfoma não Hodgkin/prevenção & controle , Camundongos , Camundongos SCID , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas de Neoplasias , Oligonucleotídeos Antissenso/farmacologia , Survivina , Células Tumorais Cultivadas
2.
Blood Cancer J ; 5: e281, 2015 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-25700246

RESUMO

To determine the biological and clinical relevance of programmed death 1 (PD-1) in follicular lymphoma (FL), we characterized PD-1(+) T-cell subsets and assessed their biological function as well as potential clinical impact. We found that PD-1 is expressed on intratumoral CD4(+) T cells with both bright and dim intensity, representing two different sub-populations of cells. By immunohistochemistry, we found that CD4(+)PD-1(high) T cells predominantly reside in the lymph node follicles, while PD-1(low) T cells are mainly located in an interfollicular pattern. Intratumoral CD4(+)PD-1(high) T cells have a TFH cell phenotype, express CXCR5, secrete IL-21 and are BCL-6 positive with no TIM-3 expression. In contrast, CD4(+)PD-1(low) T cells have an exhausted phenotype, express TIM-3 and do not express BCL-6 and CXCR5. Functionally, CD4(+)PD-1(high) T cells actively supported B-cell growth, while CD4(+)PD-1(low) T cells displayed a reduced cytokine production and cell-signal transduction. Clinically, we observed that the numbers of CD4(+) or CD8(+)PD-1(low) T cells significantly correlate with a reduced overall survival in FL patients (P=0.007 and 0.04 respectively; n=32). In contrast, the number of CD4(+)PD-1(high) T cells was not associated with patient outcome. Taken together, these results indicated that PD-1 expression defines two sub-populations with distinct functions that differentially impact patient outcome in FL.


Assuntos
Linfoma Folicular/genética , Receptor de Morte Celular Programada 1/biossíntese , Análise de Sobrevida , Subpopulações de Linfócitos T/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Feminino , Citometria de Fluxo , Regulação Neoplásica da Expressão Gênica , Humanos , Linfonodos/metabolismo , Linfonodos/patologia , Linfoma Folicular/epidemiologia , Linfoma Folicular/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Receptor de Morte Celular Programada 1/genética , Subpopulações de Linfócitos T/metabolismo
3.
Blood Cancer J ; 5: e328, 2015 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-26230952

RESUMO

The biological role of monocytes and macrophages in B-cell non-Hodgkin lymphoma (NHL) is not fully understood. We have previously reported that monocytes from patients with B-cell NHL have an immunosuppressive CD14(+)HLA-DR(low/-) phenotype that correlates with a poor prognosis. However, the underlying mechanism by which CD14(+)HLA-DR(low/-) monocytes develop in lymphoma is unknown. In the present study, we found that interleukin (IL)-10, which is increased in the serum of patients with B-cell NHL, induced the development of the CD4(+)HLA-DR(low/-) population. Using peripheral blood samples from patients with B-cell NHL, we found that absolute numbers of CD14(+) monocytic cells with an HLA-DR(low/-) phenotype were higher than healthy controls and correlated with a higher International Prognostic Index score. IL-10 serum levels were elevated in lymphoma patients compared with controls and were associated with increased peripheral monocyte counts. Treatment of monocytes with IL-10 in vitro significantly decreased HLA-DR expression and resulted in the expansion of CD14(+)HLA-DR(low/-) population. We found that lymphoma B cells produce IL-10 and supernatants from cultured lymphoma cells increased the CD14(+)HLA-DR(low/-) population. Furthermore, we found that IL-10-induced CD14(+)HLA-DR(low/-) monocytes inhibited the activation and proliferation of T cells. Taken together, these results suggest that elevated IL-10 serum levels contribute to increased numbers of immunosuppressive CD14(+)HLA-DR(low/-) monocytes in B-cell NHL.


Assuntos
Interleucina-10/fisiologia , Linfoma não Hodgkin/imunologia , Monócitos/metabolismo , Linfócitos B/metabolismo , Estudos de Casos e Controles , Proliferação de Células , Células Cultivadas , Antígenos HLA-DR/metabolismo , Humanos , Tolerância Imunológica , Receptores de Lipopolissacarídeos/metabolismo , Ativação Linfocitária , Linfoma não Hodgkin/sangue , Linfócitos T/imunologia , Linfócitos T/metabolismo
4.
Blood Cancer J ; 5: e346, 2015 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-26314988

RESUMO

Lack of remission or early relapse remains a major clinical issue in diffuse large B-cell lymphoma (DLBCL), with 30% of patients failing standard of care. Although clinical factors and molecular signatures can partially predict DLBCL outcome, additional information is needed to identify high-risk patients, particularly biologic factors that might ultimately be amenable to intervention. Using whole-exome sequencing data from 51 newly diagnosed and immunochemotherapy-treated DLBCL patients, we evaluated the association of somatic genomic alterations with patient outcome, defined as failure to achieve event-free survival at 24 months after diagnosis (EFS24). We identified 16 genes with mutations, 374 with copy number gains and 151 with copy number losses that were associated with failure to achieve EFS24 (P<0.05). Except for FOXO1 and CIITA, known driver mutations did not correlate with EFS24. Gene losses were localized to 6q21-6q24.2, and gains to 3q13.12-3q29, 11q23.1-11q23.3 and 19q13.12-19q13.43. Globally, the number of gains was highly associated with poor outcome (P=7.4 × 10(-12)) and when combined with FOXO1 mutations identified 77% of cases that failed to achieve EFS24. One gene (SLC22A16) at 6q21, a doxorubicin transporter, was lost in 54% of EFS24 failures and our findings suggest it functions as a doxorubicin transporter in DLBCL cells.


Assuntos
Exoma/genética , Linfoma Difuso de Grandes Células B/genética , Proteínas de Transporte de Cátions Orgânicos/genética , Idoso , Idoso de 80 Anos ou mais , Transporte Biológico , Terapia Combinada , Variações do Número de Cópias de DNA , Análise Mutacional de DNA , Doxorrubicina/metabolismo , Feminino , Estudos de Associação Genética , Genoma Humano , Humanos , Estimativa de Kaplan-Meier , Linfoma Difuso de Grandes Células B/mortalidade , Linfoma Difuso de Grandes Células B/terapia , Masculino , Pessoa de Meia-Idade , Deleção de Sequência , Resultado do Tratamento
5.
J Anal Toxicol ; 9(5): 222-6, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-4057960

RESUMO

An analytical procedure for simultaneous determination of codeine and morphine in urine is described. The detection of codeine and morphine is based on liquid-liquid extraction and derivatization to the acetylated compounds. The acetylated codeine and morphine are separated by capillary gas chromatography and identified mass spectrometrically by selected ion monitoring (SIM). Quantitative determination was carried out by SIM using nalorphine as internal standard. Excellent linearity was obtained over a concentration range of 25 to 800 ng/mL. The overall recovery for codeine and morphine in the extraction was found to be 58% and 40%, respectively. The on-column sensitivity for both compounds was 2 ng at a peak-to-noise ratio of 5:1. The derivatives, acetylcodeine, diacetylmorphine, and diacetylnalorphine were stable at room temperature for 72 hr.


Assuntos
Codeína/urina , Cromatografia Gasosa-Espectrometria de Massas , Morfina/urina , Humanos
6.
Math Popul Stud ; 5(1): 75-85, 121, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-12288880

RESUMO

"The aim of the present paper is to illustrate how extremely complex patterns may be generated in a simple model of educational planning. In particular, we will show that certain dependencies of the flow rates on the teacher/student ratio imply nonlinearities which are substantial enough to generate erratic behaviour of the time paths. The main message is that chaos in educational planning may result from assumptions which are indeed qualitatively realistic but which are quantitatively exaggerated." (SUMMARY IN FRE)


Assuntos
Educação , Planejamento em Saúde , Modelos Teóricos
7.
Leukemia ; 28(9): 1872-84, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24569779

RESUMO

Transforming growth factor beta (TGF-ß) has an important role in mediating T-cell suppression in B-cell non-Hodgkin lymphoma (NHL). However, the underlying mechanism responsible for TGF-ß-mediated inhibition of effector memory T (Tm) cells is largely unknown. As reported here, we show that exhaustion is a major mechanism by which TGF-ß inhibits Tm cells, and TGF-ß mediated exhaustion is associated with upregulation of CD70. We found that TGF-ß upregulates CD70 expression on effector Tm cells while it preferentially induces Foxp3 expression in naive T cells. CD70 induction by TGF-ß is Smad3-dependent and involves IL-2/Stat5 signaling. CD70+ T cells account for TGF-ß-induced exhaustion of effector Tm cells. Both TGF-ß-induced and preexisting intratumoral CD70+ effector Tm cells from B-cell NHL have an exhausted phenotype and express higher levels of PD-1 and TIM-3 compared with CD70- T cells. Signaling transduction, proliferation and cytokine production are profoundly decreased in these cells, and they are highly susceptible to apoptosis. Clinically, intratumoral CD70-expressing T cells are prevalent in follicular B-cell lymphoma (FL) biopsy specimens, and increased numbers of intratumoral CD70+ T cells correlate with an inferior patient outcome. These findings confirm TGF-ß-mediated effector Tm cell exhaustion as an important mechanism of immune suppression in B-cell NHL.


Assuntos
Ligante CD27/fisiologia , Memória Imunológica , Linfoma de Células B/imunologia , Linfócitos T/imunologia , Fator de Crescimento Transformador beta/farmacologia , Apoptose , Ligante CD27/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Receptor Celular 2 do Vírus da Hepatite A , Humanos , Interleucina-2/fisiologia , Proteínas de Membrana/análise , Receptor de Morte Celular Programada 1/análise , Fator de Transcrição STAT5/fisiologia , Transdução de Sinais , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/fisiologia
8.
Blood Cancer J ; 4: e183, 2014 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-24531446

RESUMO

Massively parallel sequencing analyses have revealed a common mutation within the MYD88 gene (MYD88L265P) occurring at high frequencies in many non-Hodgkin lymphomas (NHLs) including the rare lymphoplasmacytic lymphoma, Waldenström's macroglobulinemia (WM). Using whole-exome sequencing, Sanger sequencing and allele-specific PCR, we validate the initial studies and detect the MYD88L265P mutation in the tumor genome of 97% of WM patients analyzed (n=39). Due to the high frequency of MYD88 mutation in WM and other NHL, and its known effects on malignant B-cell survival, therapeutic targeting of MYD88 signaling pathways may be clinically useful. However, we are lacking a thorough characterization of the role of intermediary signaling proteins on the biology of MYD88L265P-expressing B cells. We report here that MYD88L265P signaling is constitutively active in both WM and diffuse large B-cell lymphoma cells leading to heightened MYD88L265P, IRAK and TRAF6 oligomerization and NF-κB activation. Furthermore, we have identified the signaling protein, TAK1, to be an essential mediator of MYD88L265P-driven signaling, cellular proliferation and cytokine secretion in malignant B cells. Our studies highlight the biological significance of MYD88L265P in NHL and reveal TAK1 inhibition to be a potential therapeutic strategy for the treatment of WM and other diseases characterized by MYD88L265P.

10.
Blood Cancer J ; 1(6): e24, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22829168

RESUMO

MicroRNAs (miRNAs) are involved in the regulation of many cellular processes including hematopoiesis, with the aberrant expression of differentiation-stage specific miRNA associated with lymphomagenesis. miRNA profiling has been essential for understanding the underlying biology of many hematological malignancies; however the miRNA signature of the diverse tumor clone associated with Waldenstrom's macroglobulinemia (WM), consisting of B lymphocytes, plasmacytes and lymphoplasmacytic cells, has not been characterized. We have investigated the expression of over 13 000 known and candidate miRNAs in both CD19(+) and CD138(+) WM tumor cells, as well as in their malignant and non-malignant counterparts. Although neither CD19(+) nor CD138(+) WM cells were defined by a distinct miRNA profile, the combination of all WM cells revealed a unique miRNA transcriptome characterized by the dysregulation of many miRNAs previously identified as crucial for normal B-cell lineage differentiation. Specifically, miRNA-9(*)/152/182 were underexpressed in WM, whereas the expression of miRNA-21/125b/181a/193b/223/363 were notably increased (analysis of variance; P<0.0001). Future studies focusing on the effects of these dysregulated miRNAs will provide further insight into the mechanisms responsible for the pathogenesis of WM.

12.
Leukemia ; 22(12): 2240-6, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18830264

RESUMO

Multiple myeloma (MM) is a progressive disease that results from dysregulated proliferation of plasma cells. Although, causative factors such as genetic events and altered expression of anti-apoptotic factors have been described in a number of patients, the mechanistic details that drive myeloma development and continued growth of malignant cells remain largely undefined. Numerous growth factors, including interleukin (IL)-6, Insulin-like growth factor-1 and IL-10 have been shown to promote growth of MM cells suggesting a significant role for cytokines in this disease. Interferon (IFN)-lambda1 is a new member of the Class II cytokine family that, similar to IFN-alpha, has been shown to mediate viral immunity. In light of data supporting a role for cytokines in myeloma, we investigated the significance of IFN-lambda1 on myeloma cell biology. Our studies show for the first time that myeloma cells bind to soluble IFN-lambda1, and that IFN-lambda1 induces myeloma cell growth and protects against dexamethasone-induced cell death. Our data also show that IFN-lambda1 induces phosphorylation of STAT1, STAT3 and Erk. Taken together, our results suggest that IFN-lambda1 may regulate myeloma cell biology and could prove to be therapeutically important.


Assuntos
Linfócitos B/metabolismo , Linfócitos B/patologia , Interleucinas/metabolismo , Mieloma Múltiplo/metabolismo , Mieloma Múltiplo/patologia , Linfócitos B/imunologia , Morte Celular/efeitos dos fármacos , Morte Celular/imunologia , Divisão Celular/efeitos dos fármacos , Divisão Celular/imunologia , Linhagem Celular Tumoral , Dexametasona/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Glucocorticoides/farmacologia , Humanos , Interferons , Interleucinas/genética , Interleucinas/imunologia , Mieloma Múltiplo/imunologia , Fosforilação , Fator de Transcrição STAT1/metabolismo , Fator de Transcrição STAT3/metabolismo , Células Tumorais Cultivadas
13.
Leukemia ; 22(6): 1139-43, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18401419

RESUMO

Peripheral T-cell lymphomas (PTCLs) are fatal in the majority of patients and novel treatments, such as protein tyrosine kinase (PTK) inhibition, are needed. The recent finding of SYK/ITK translocations in rare PTCLs led us to examine the expression of Syk PTK in 141 PTCLs. Syk was positive by immunohistochemistry (IHC) in 133 PTCLs (94%), whereas normal T cells were negative. Western blot on frozen tissue (n=6) and flow cytometry on cell suspensions (n=4) correlated with IHC results in paraffin. Additionally, western blot demonstrated that Syk-positive PTCLs show tyrosine (525/526) phosphorylation, known to be required for Syk activation. Fluorescence in situ hybridization showed no SYK/ITK translocation in 86 cases. Overexpression of Syk, phosphorylation of its Y525/526 residues and the availability of orally available Syk inhibitors suggest that Syk merits further evaluation as a candidate target for pharmacologic PTK inhibition in patients with PTCL.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Linfoma de Células T Periférico/enzimologia , Proteínas Tirosina Quinases/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Western Blotting , Criança , Pré-Escolar , Cromossomos Humanos Par 5/genética , Cromossomos Humanos Par 9/genética , Feminino , Citometria de Fluxo , Humanos , Técnicas Imunoenzimáticas , Imunofenotipagem , Hibridização in Situ Fluorescente , Peptídeos e Proteínas de Sinalização Intracelular/genética , Linfoma Extranodal de Células T-NK/enzimologia , Linfoma Extranodal de Células T-NK/genética , Linfoma Extranodal de Células T-NK/patologia , Linfoma Anaplásico de Células Grandes/enzimologia , Linfoma Anaplásico de Células Grandes/genética , Linfoma Anaplásico de Células Grandes/patologia , Linfoma Cutâneo de Células T/enzimologia , Linfoma Cutâneo de Células T/genética , Linfoma Cutâneo de Células T/patologia , Linfoma de Células T Periférico/genética , Linfoma de Células T Periférico/patologia , Masculino , Pessoa de Meia-Idade , Fosforilação , Proteínas Tirosina Quinases/genética , Quinase Syk , Translocação Genética , Tirosina/metabolismo
14.
JAMA ; 265(22): 2961-2, 1991 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-2033765
15.
Dent Manage ; 11(1): 38 passim, 1971 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-5277274
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