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1.
Braz J Biol ; 84: e269043, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36700587

RESUMO

Camel milk was obtained from A-block UVAS Ravi Campus Pattoki. After pasteurization at 72 °C (15 sec) it was cooled to 42 °C, then glutathione treated transglutaminase enzyme was added with the concentration of 0.5 g/300 mL, 1 g/300 mL, 1.5 g/300 mL, 2 g/300 mL while control sample with the addition of 1.5 g/300 mL gelatin. Then inoculation of milk was done with standard cultures of Yoghurt Lactobacillus delbrueckii subsp bulgaricus and Streptococcus thermophilus at the rate of 2% for 3-4 hours at 42 °C. Samples were stored at 4 °C and were analyzed on 1st day and 28th day of storage. In our findings, there was slight increase in sensorial properties of all the samples. It was also observed that syneresis was reduced with the increase of enzyme quantity.


Assuntos
Lactobacillus delbrueckii , Leite , Animais , Iogurte , Camelus , Fermentação
2.
Braz. j. biol ; 83: 1-8, 2023. graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468842

RESUMO

Poultry industry is expanding rapidly and producing million tons of feather waste annually. Massive production of keratinaceous byproducts in the form of industrial wastes throughout the world necessitates its justified utilization. Chemical treatment of keratin waste is proclaimed as an eco-destructive approach by various researchers since it generates secondary pollutants. Keratinase released by a variety of microbes (bacteria and fungi) can be used for the effective treatment of keratin waste. Microbial degradation of keratin waste is an emerging and eco-friendly approach and offers dual benefits, i.e., treatment of recalcitrant pollutant (keratin) and procurement of a commercially important enzyme (keratinase). This study involves the isolation, characterization, and potential utility of fungal species for the degradation of chicken-feather waste through submerged and solid-state fermentation. The isolated fungus was identified and characterized as Aspergillus (A.) flavus. In a trial of 30 days, it was appeared that 74 and 8% feather weight was reduced through sub-merged and solid-state fermentation, respectively by A. flavus. The pH of the growth media in submerged fermentation was changed from 4.8 to 8.35. The exploited application of keratinolytic microbes is, therefore, recommended for the treatment of keratinaceous wastes to achieve dual benefits of remediation.


A indústria avícola está se expandindo rapidamente e produzindo milhões de toneladas de resíduos de penas anualmente. A produção massiva de subprodutos queratinosos na forma de resíduos agrícolas e industriais em todo o mundo exige sua utilização justificada. O tratamento químico de resíduos de queratina é proclamado como uma abordagem ecodestrutiva por vários pesquisadores, uma vez que gera poluentes secundários. A queratinase liberada por uma variedade de micróbios (bactérias e fungos) pode ser usada para o tratamento eficaz de resíduos de queratina. A degradação microbiana de resíduos de queratina é uma abordagem emergente e ecológica e oferece benefícios duplos, ou seja, tratamento de poluente recalcitrante (queratina) e obtenção de uma enzima comercialmente importante (queratinase). Este estudo envolve o isolamento, caracterização e utilidade potencial de espécies de fungos para a degradação de resíduos de penas de frango por meio da fermentação submersa e em estado sólido. O fungo isolado foi identificado e caracterizado como Aspergillus (A.) flavus. Em um ensaio de 30 dias, constatou-se que 74% e 8% do peso das penas foram reduzidos por A. flavus, respectivamente, por meio da fermentação submersa e em estado sólido. O pH do meio de crescimento em fermentação submersa foi alterado de 4,8 para 8,35. A aplicação explorada de micróbios queratinolíticos é, portanto, recomendada para o tratamento de resíduos ceratinosos para obter benefícios duplos de remediação.


Assuntos
Aspergillus flavus/isolamento & purificação , Biotransformação , Queratinas/análise , Queratinas/toxicidade
3.
Braz. j. biol ; 832023.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469058

RESUMO

Abstract Poultry industry is expanding rapidly and producing million tons of feather waste annually. Massive production of keratinaceous byproducts in the form of industrial wastes throughout the world necessitates its justified utilization. Chemical treatment of keratin waste is proclaimed as an eco-destructive approach by various researchers since it generates secondary pollutants. Keratinase released by a variety of microbes (bacteria and fungi) can be used for the effective treatment of keratin waste. Microbial degradation of keratin waste is an emerging and eco-friendly approach and offers dual benefits, i.e., treatment of recalcitrant pollutant (keratin) and procurement of a commercially important enzyme (keratinase). This study involves the isolation, characterization, and potential utility of fungal species for the degradation of chicken-feather waste through submerged and solid-state fermentation. The isolated fungus was identified and characterized as Aspergillus (A.) flavus. In a trial of 30 days, it was appeared that 74 and 8% feather weight was reduced through sub-merged and solid-state fermentation, respectively by A. flavus. The pH of the growth media in submerged fermentation was changed from 4.8 to 8.35. The exploited application of keratinolytic microbes is, therefore, recommended for the treatment of keratinaceous wastes to achieve dual benefits of remediation.


Resumo A indústria avícola está se expandindo rapidamente e produzindo milhões de toneladas de resíduos de penas anualmente. A produção massiva de subprodutos queratinosos na forma de resíduos agrícolas e industriais em todo o mundo exige sua utilização justificada. O tratamento químico de resíduos de queratina é proclamado como uma abordagem ecodestrutiva por vários pesquisadores, uma vez que gera poluentes secundários. A queratinase liberada por uma variedade de micróbios (bactérias e fungos) pode ser usada para o tratamento eficaz de resíduos de queratina. A degradação microbiana de resíduos de queratina é uma abordagem emergente e ecológica e oferece benefícios duplos, ou seja, tratamento de poluente recalcitrante (queratina) e obtenção de uma enzima comercialmente importante (queratinase). Este estudo envolve o isolamento, caracterização e utilidade potencial de espécies de fungos para a degradação de resíduos de penas de frango por meio da fermentação submersa e em estado sólido. O fungo isolado foi identificado e caracterizado como Aspergillus (A.) flavus. Em um ensaio de 30 dias, constatou-se que 74% e 8% do peso das penas foram reduzidos por A. flavus, respectivamente, por meio da fermentação submersa e em estado sólido. O pH do meio de crescimento em fermentação submersa foi alterado de 4,8 para 8,35. A aplicação explorada de micróbios queratinolíticos é, portanto, recomendada para o tratamento de resíduos ceratinosos para obter benefícios duplos de remediação.

4.
Braz. j. biol ; 83: e246389, 2023. graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1285638

RESUMO

Abstract Poultry industry is expanding rapidly and producing million tons of feather waste annually. Massive production of keratinaceous byproducts in the form of industrial wastes throughout the world necessitates its justified utilization. Chemical treatment of keratin waste is proclaimed as an eco-destructive approach by various researchers since it generates secondary pollutants. Keratinase released by a variety of microbes (bacteria and fungi) can be used for the effective treatment of keratin waste. Microbial degradation of keratin waste is an emerging and eco-friendly approach and offers dual benefits, i.e., treatment of recalcitrant pollutant (keratin) and procurement of a commercially important enzyme (keratinase). This study involves the isolation, characterization, and potential utility of fungal species for the degradation of chicken-feather waste through submerged and solid-state fermentation. The isolated fungus was identified and characterized as Aspergillus (A.) flavus. In a trial of 30 days, it was appeared that 74 and 8% feather weight was reduced through sub-merged and solid-state fermentation, respectively by A. flavus. The pH of the growth media in submerged fermentation was changed from 4.8 to 8.35. The exploited application of keratinolytic microbes is, therefore, recommended for the treatment of keratinaceous wastes to achieve dual benefits of remediation.


Resumo A indústria avícola está se expandindo rapidamente e produzindo milhões de toneladas de resíduos de penas anualmente. A produção massiva de subprodutos queratinosos na forma de resíduos agrícolas e industriais em todo o mundo exige sua utilização justificada. O tratamento químico de resíduos de queratina é proclamado como uma abordagem ecodestrutiva por vários pesquisadores, uma vez que gera poluentes secundários. A queratinase liberada por uma variedade de micróbios (bactérias e fungos) pode ser usada para o tratamento eficaz de resíduos de queratina. A degradação microbiana de resíduos de queratina é uma abordagem emergente e ecológica e oferece benefícios duplos, ou seja, tratamento de poluente recalcitrante (queratina) e obtenção de uma enzima comercialmente importante (queratinase). Este estudo envolve o isolamento, caracterização e utilidade potencial de espécies de fungos para a degradação de resíduos de penas de frango por meio da fermentação submersa e em estado sólido. O fungo isolado foi identificado e caracterizado como Aspergillus (A.) flavus. Em um ensaio de 30 dias, constatou-se que 74% e 8% do peso das penas foram reduzidos por A. flavus, respectivamente, por meio da fermentação submersa e em estado sólido. O pH do meio de crescimento em fermentação submersa foi alterado de 4,8 para 8,35. A aplicação explorada de micróbios queratinolíticos é, portanto, recomendada para o tratamento de resíduos ceratinosos para obter benefícios duplos de remediação.


Assuntos
Animais , Galinhas , Plumas , Fermentação , Fungos , Resíduos Industriais , Queratinas/metabolismo
5.
Braz J Biol ; 83: e248026, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35544900

RESUMO

Poultry industry is amongst highly developed industries of Pakistan, fulfilling the protein demand of rapidly increasing population. On the other hand, the untreated poultry waste is causing several health and environmental problems. The current study was designed to check the potential of keratinolytic fungal species for the conversion of chicken-feather waste into biofortified compost. For the purpose, three fungal species were isolated from soil samples. These strains were pure cultured and then characterized phenotypically and genotypically. BLAST searches of 18S rDNA nucleotide sequence of the fungal isolates revealed that the two fungal isolates belonged to genus Aspergillus and one belonged to genus Chrysosporium. Optimum temperature for Aspergillus flavus, Aspergillus niger and Chrysosporium queenslandicum was 29, 26 and 25 oC, respectively. A. flavus showed maximum (53%) feather degradation, A. niger degraded feather waste up to 37%, while C. queenslandicum showed 21% keratinolytic activity on chicken feathers at their respective temperature optima. The degradation potential of these fungal species showed their ability to form compost that has agro-industrial importance.


Assuntos
Compostagem , Plumas , Animais , Galinhas , Plumas/metabolismo , Plumas/microbiologia , Aves Domésticas , Temperatura
6.
Braz J Biol ; 83: e246389, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34320050

RESUMO

Poultry industry is expanding rapidly and producing million tons of feather waste annually. Massive production of keratinaceous byproducts in the form of industrial wastes throughout the world necessitates its justified utilization. Chemical treatment of keratin waste is proclaimed as an eco-destructive approach by various researchers since it generates secondary pollutants. Keratinase released by a variety of microbes (bacteria and fungi) can be used for the effective treatment of keratin waste. Microbial degradation of keratin waste is an emerging and eco-friendly approach and offers dual benefits, i.e., treatment of recalcitrant pollutant (keratin) and procurement of a commercially important enzyme (keratinase). This study involves the isolation, characterization, and potential utility of fungal species for the degradation of chicken-feather waste through submerged and solid-state fermentation. The isolated fungus was identified and characterized as Aspergillus (A.) flavus. In a trial of 30 days, it was appeared that 74 and 8% feather weight was reduced through sub-merged and solid-state fermentation, respectively by A. flavus. The pH of the growth media in submerged fermentation was changed from 4.8 to 8.35. The exploited application of keratinolytic microbes is, therefore, recommended for the treatment of keratinaceous wastes to achieve dual benefits of remediation.


Assuntos
Galinhas , Plumas , Animais , Fermentação , Fungos , Resíduos Industriais , Queratinas/metabolismo
7.
ESMO Open ; 6(4): 100172, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34242968

RESUMO

BACKGROUND: More than 80% of anaplastic lymphoma kinase (ALK)-positive anaplastic large cell lymphoma (ALCL) patients harbor the (nucleophosmin) NPM1-ALK fusion gene t(2;5) chromosomal translocation. We evaluated the preclinical and clinical efficacy of ceritinib treatment of this aggressive lymphoma. MATERIALS AND METHODS: We studied the effects of ceritinib treatment in NPM1-ALK+ T-cell lymphoma cell lines in vitro and on tumor size and survival advantage in vivo utilizing tumor xenografts. We treated an NPM1-ALK+ ALCL patient with ceritinib. We reviewed all hematologic malignancies profiled by a large hybrid-capture next-generation sequencing (NGS)-based comprehensive genomic profiling assay for ALK alterations. RESULTS: In our in vitro experiments, ceritinib inhibited constitutive activation of the fusion kinase NPM1-ALK and downstream effector molecules STAT3, AKT, and ERK1/2, and induced apoptosis of these lymphoma cell lines. Cell cycle analysis following ceritinib treatment showed G0/G1 arrest with a concomitant decrease in the percentage of cells in S and G2/M phases. Further, treatment with ceritinib in the NPM1-ALK+ ALCL xenograft model resulted in tumor regression and improved survival. Of 19 272 patients with hematopoietic diseases sequenced, 58 patients (0.30%) harbored ALK fusions that include histiocytic disorders, multiple myeloma, B-cell neoplasms, Castleman's disease, and juvenile xanthogranuloma. A multiple relapsed NPM1-ALK+ ALCL patient treated with ceritinib achieved complete remission with ongoing clinical benefit to date, 5 years after initiation of therapy. CONCLUSIONS: This ceritinib translational study in NPM1-ALK+ ALCL provides a strong rationale for a prospective study of ceritinib in ALK+ T-cell lymphomas and other ALK+ hematologic malignancies.


Assuntos
Linfoma Anaplásico de Células Grandes , Quinase do Linfoma Anaplásico/genética , Humanos , Linfoma Anaplásico de Células Grandes/tratamento farmacológico , Linfoma Anaplásico de Células Grandes/genética , Nucleofosmina , Estudos Prospectivos , Pirimidinas , Receptores Proteína Tirosina Quinases/genética , Sulfonas
8.
Leukemia ; 28(1): 118-28, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23608884

RESUMO

Chronic lymphocytic leukemia (CLL) patients with deletion of chromosome 17p, where the p53 gene is located, often develop more aggressive disease with poor clinical outcomes. To investigate the underlying mechanisms for the highly malignant phenotype of 17p- CLL and to facilitate in vivo evaluation of potential drugs against CLL with p53 deletion, we have generated a mouse model with TCL1-Tg:p53(-/-) genotype. These mice develop B-cell leukemia at an early age with an early appearance of CD5+ / IgM+ B cells in the peritoneal cavity and spleen, and exhibit an aggressive path of disease development and drug resistance phenotype similar to human CLL with 17p deletion. The TCL1-Tg:p53(-/-) leukemia cells exhibit higher survival capacity and are more drug resistant than the leukemia cells from TCL1-Tg:p53wt mice. Analysis of microRNA expression reveals that p53 deletion resulted in a decrease of miR-15a and miR-16-1, leading to an elevated expression of Mcl-1. Primary leukemia cells from CLL patients with 17p deletion also show a decrease in miR-15a/miR-16-1 and an increase in Mcl-1. Our study suggests that the p53/miR15a/16-1/Mcl-1 axis may be an important pathway that regulates Mcl-1 expression and contributes to drug resistance and aggressive phenotype in CLL cells with loss of p53.


Assuntos
Modelos Animais de Doenças , Genes p53 , MicroRNAs/genética , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Proteínas Proto-Oncogênicas/genética , Animais , Linhagem Celular Tumoral , Humanos , Camundongos , Camundongos Transgênicos
9.
BMC Public Health ; 12: 1084, 2012 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-23253186

RESUMO

BACKGROUND: A clear understanding of the social and behavioral risk factors, and knowledge gaps, related to exposure to malaria are essential when developing guidelines and recommendations for more effective disease prevention in many malaria endemic areas of the world including Bangladesh and elsewhere in the South East Asia. To-date, the level of knowledge that human populations, residing in moderate to high malaria risk zones, have with respect to the basic pathogen transmission dynamics, risk factors for malaria or disease preventative strategies, has not been assessed in Bangladesh. The purpose of this study was to address this gap by conducting surveys of the knowledge, attitudes and practices (KAP) of people, from variable socio-demographic backgrounds, residing in selected rural malaria endemic areas in Bangladesh. METHODS: The KAP survey was conducted in portions of six different malaria endemic districts in Bangladesh from July to October 2011. The survey consisted of interviewing residence of these malaria endemic districts using a structured questionnaire and interviewers also completed observational checklists at each household where people were interviewed. The study area was further divided into two zones (1 and 2) based on differences in the physical geography and level of malaria endemicity in the two zones. Data from the questionnaires and observational checklists were analysised using Statistical Package for Social Sciences 16.0 (SPSS, Inc., Chicago, IL, USA). RESULTS: A total of 468 individuals from individual households were interviewed, and most respondents were female. Monthly incomes varied within and among the zones. It was found that 46.4% and 41% of respondents' family had malaria within the past one year in zones 1 and 2, respectively. Nearly 86% of the respondents did not know the exact cause of malaria or the role of Anopheles mosquitoes in the pathogen's transmission. Knowledge on malaria transmission and symptoms of the respondents of zones 1 and 2 were significantly (p<0.01) different. The majority of respondents from both zones believed that bed nets were the main protective measure against malaria, but a significant relationship was not found between the use of bed net and prevalence of malaria. A significant relationship (p<0.05) between level of education with malaria prevalence was found in zone 1. There was a positive correlation between the number of family members and the prevalence of malaria. Houses with walls had a strong positive association with malaria. Approximately 50% of the households of zones 1 and 2 maintained that they suffered from malaria within the last year. A significant association (p<0.01) between malaria and the possession of domestic animals in their houses was found in both zones. People who spent time outside in the evening were more likely to contract malaria than those who did not. CONCLUSION: To address the shortcomings in local knowledge about malaria, health personnel working in malaria endemic areas should be trained to give more appropriate counseling in an effort to change certain deeply entrenched traditional behaviors such as spending time outdoors in the evening, improper use of bed nets and irregular use of insecticides during sleep.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Malária/prevenção & controle , Malária/psicologia , Controle de Mosquitos/métodos , Adolescente , Adulto , Animais , Bangladesh/epidemiologia , Lista de Checagem , Feminino , Habitação/normas , Humanos , Mosquiteiros Tratados com Inseticida , Entrevistas como Assunto , Malária/epidemiologia , Malária/transmissão , Masculino , Pessoa de Meia-Idade , Prevalência , Características de Residência , Fatores de Risco , Fatores Socioeconômicos , Inquéritos e Questionários , Adulto Jovem
10.
Oncogene ; 29(21): 3044-53, 2010 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-20348955

RESUMO

SSBP proteins bind and stabilize transcriptional cofactor LIM domain-binding protein1 (LDB1) from proteosomal degradation to promote tissue-specific transcription through an evolutionarily conserved pathway. The human SSBP2 gene was isolated as a candidate tumor suppressor from a critical region of loss in chromosome 5q14.1. By gene targeting, we show increased predisposition to B-cell lymphomas and carcinomas in Ssbp2(-/-) mice. Remarkably, loss of Ssbp2 causes increased LDB1 turnover in the thymus, a pathway exploited in Trp53(-/-)Ssbp2(-/-) mice to develop highly aggressive, immature thymic lymphomas. Using T-cell differentiation as a model, we report a stage-specific upregulation of Ssbp2 expression, which in turn regulates LDB1 turnover under physiological conditions. Furthermore, transcript levels of pTalpha, a target of LDB1-containing complex, and a critical regulator T-cell differentiation are reduced in Ssbp2(-/-) immature thymocytes. Our findings suggest that disruption of the SSBP2-regulated pathways may be an infrequent but critical step in malignant transformation of multiple tissues.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Genes Supressores de Tumor , Animais , Diferenciação Celular , Cricetinae , Proteínas de Ligação a DNA/deficiência , Proteínas de Ligação a DNA/genética , Genes Letais , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Linfócitos T/citologia , Linfócitos T/imunologia , Timo/citologia , Timo/patologia , Transcrição Gênica , Proteína Supressora de Tumor p53/genética
11.
Leukemia ; 24(5): 1025-36, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20200556

RESUMO

Hedgehog (HH) signaling is important in the pathogenesis of several malignancies. Recently, we described that HH signaling proteins are commonly expressed in diffuse large B-cell lymphoma (DLBCL); however, the functional role of HH pathway in DLBCL has not been explored. Here, we assessed the possibility that HH pathway activation contributes to the survival of DLBCL. We found that HH signaling inhibition induces predominantly cell-cycle arrest in DLBCL cells of germinal center (GC) B-cell type, and apoptosis in DLBCL cells of activated B-cell (ABC) type. Apoptosis after HH signaling inhibition in DLBCL cells of ABC type was associated with downregulation of BCL2; however HH inhibition was not associated with BCL2 downregulation in DLBCL of GC type. Functional inhibition of BCL2 significantly increased apoptosis induced by HH inhibition in DLBCL cells of both types. We also showed that DLBCL cells synthesize, secrete and respond to endogenous HH ligands, providing support for the existence of an autocrine HH signaling loop. Our findings provide novel evidence that dysregulation of HH pathway is involved in the biology of DLBCL and have significant therapeutic implications as they identify HH signaling as a potential therapeutic target in DLBCL, in particular for those lymphomas expressing the HH receptor smoothened.


Assuntos
Proliferação de Células , Regulação Leucêmica da Expressão Gênica , Centro Germinativo/patologia , Proteínas Hedgehog/metabolismo , Linfoma Difuso de Grandes Células B/metabolismo , Linfoma Difuso de Grandes Células B/patologia , Transdução de Sinais , Apoptose , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Western Blotting , Ciclo Celular , Sobrevivência Celular , Proteínas Hedgehog/genética , Humanos , Linfoma Difuso de Grandes Células B/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas
12.
Leukemia ; 23(10): 1836-46, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19494838

RESUMO

Interleukin-21 (IL-21) has been recently shown to modulate the growth of specific types of B-cell neoplasm. Here, we studied the biological effects of IL-21 in mantle cell lymphoma (MCL). All MCL cell lines and tumors examined expressed the IL-21 receptor. Addition of recombinant IL-21 (rIL-21) in vitro effectively induced STAT1 activation and apoptosis in MCL cells. As STAT1 is known to have tumor-suppressor functions, we hypothesized that STAT1 is important in mediating IL-21-induced apoptosis in MCL cells. In support of this hypothesis, inhibition of STAT1 expression using siRNA significantly decreased the apoptotic responses induced by IL-21. To further investigate the mechanism of IL-21-mediated apoptosis, we employed oligonucleotide arrays to evaluate changes in the expression of apoptosis-related genes induced by rIL-21; rIL-21 significantly upregulated three proapoptotic proteins (BIK, NIP3 and HARAKIRI) and downregulated two antiapoptotic proteins (BCL-2 and BCL-XL/S) as well as tumor necrosis factor-alpha. Using an ELISA-based assay, we demonstrated that rIL-21 significantly decreased the DNA binding of nuclear factor-kappaB, a transcriptional factor known to be a survival signal for MCL cells. To conclude, IL-21 can effectively induce apoptosis in MCL via a STAT1-dependent pathway. Further understanding of IL-21-mediated apoptosis in MCL may be useful in designing novel therapeutic approaches for this disease.


Assuntos
Apoptose/efeitos dos fármacos , Interleucinas/farmacologia , Linfoma de Célula do Manto/patologia , Fator de Transcrição STAT1/metabolismo , Western Blotting , Citometria de Fluxo , Imunofluorescência , Perfilação da Expressão Gênica , Humanos , Immunoblotting , Linfoma de Célula do Manto/genética , Linfoma de Célula do Manto/metabolismo , Potencial da Membrana Mitocondrial , NF-kappa B/genética , NF-kappa B/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/farmacologia , Receptores de Interleucina-21/genética , Receptores de Interleucina-21/metabolismo , Proteínas Recombinantes/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Transcrição STAT1/antagonistas & inibidores , Fator de Transcrição STAT1/genética , Células Tumorais Cultivadas
13.
FASEB J ; 23(5): 1405-14, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19151334

RESUMO

Both signal transducer and activator of transcription 3 (STAT3) and SALL4 are important in maintaining the pluripotent and self-renewal state of embryonic stem cells. We hypothesized that STAT3, a latent transcriptional factor, may regulate the gene expression of SALL4. In support of this hypothesis, DNA sequence analysis of the SALL4 gene promoter revealed four putative STAT3-binding sites. Using a SALL4-luciferase reporter gene assay, we found that modulation of the STAT3 activity significantly up-regulated the luciferase activity. By chromatin immunoprecipitation, the segment of the SALL4 promoter showing the highest affinity to STAT3 was localized to -366 to -163, in which there was only one putative STAT3 binding site starting at -199. Site-directed mutagenesis of all four putative STAT3-binding sites in the SALL4 promoter significantly reduced its responsiveness to STAT3, although the most dramatic effect was seen at the binding site starting at -199. We further tested the functional relationship between STAT3 and SALL4 using MDA-MB-231, a breast cell line carrying constitutive SALL4 expression and STAT3 activity. Down-regulation of the STAT3 activity using a dominant-negative construct resulted in a significant decrease in the expression of SALL4. To conclude, our data suggest that STAT3 and SALL4 probably cooperate in both physiological and pathological states.


Assuntos
Fator de Transcrição STAT3/fisiologia , Fatores de Transcrição/genética , Sequência de Bases , Sítios de Ligação , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Imunoprecipitação da Cromatina , Sequência Consenso , Regulação para Baixo , Humanos , Mutagênese Sítio-Dirigida , Regiões Promotoras Genéticas , Tetraciclina/farmacologia
14.
Leukemia ; 22(8): 1595-603, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18509351

RESUMO

One of the characteristic features of anaplastic lymphoma kinase (ALK)(+), anaplastic large cell lymphoma (ALK(+)ALCL) is the constitutive activation of signal transducers and activators of transcription-3 (STAT3), a defect believed to be important for the pathogenesis of these tumors. In this report, we describe the existence of an autocrine stimulatory loop involving interleukin-22 (IL-22) that contributes to STAT3 activation and tumorigenicity of ALK(+)ALCL. The IL-22 receptor, a heterodimer composed of IL-22R1 and IL-10R2, was expressed in all ALK(+)ALCL cell lines and tumors examined. The expression of IL-22R1 in ALK(+)ALCL is aberrant, as this protein is absent in benign lymphocytes. Although ALK(+)ALCL cells produce endogenous IL-22, addition of recombinant IL-22 to ALK(+)ALCL cell lines significantly increased STAT3 activation, cell proliferation and colony formation in soft agar. Opposite biological effects were observed in cells treated with recombinant IL-22 binding protein (a naturally occurring IL-22 decoy) or IL-22-neutralizing antibody. Nucleophosmin (NPM)-ALK, the characteristic fusion gene oncoprotein expressed in ALK(+)ALCL, directly contributes to the aberrant expression of IL-22R1, as transfection of NPM-ALK in Jurkat cells-induced IL-22R1 expression and IL-22-mediated STAT3 activation. To conclude, for the first time, we demonstrate the importance of the IL-22 autocrine pathway in a lymphoid malignancy, and reveal yet another novel function of NPM-ALK.


Assuntos
Interleucinas/fisiologia , Linfoma Anaplásico de Células Grandes/patologia , Receptores de Interleucina/genética , Sequência de Bases , Primers do DNA , Ensaio de Imunoadsorção Enzimática , Humanos , Interleucinas/metabolismo , Linfoma Anaplásico de Células Grandes/genética , Sistema de Sinalização das MAP Quinases , Microscopia Confocal , Microscopia de Fluorescência , RNA Interferente Pequeno , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Interleucina 22
15.
J Pathol ; 212(4): 402-10, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17503411

RESUMO

Chronic myeloid leukaemia (CML) is characterized by t(9;22)(q34;q11) and the aberrant expression of the fusion protein Bcr-Abl that leads to constitutive activation of c-Abl kinase. Bcr-Abl plays a major role in the development and progression of CML through chronic, accelerated, and blast phases. The interaction between Bcr-Abl and other oncogenic molecules has been extensively documented. Nonetheless, negative regulatory mechanisms of Bcr-Abl are not completely defined. One major inhibitory pathway is mediated via the SH2 domain-containing protein tyrosine phosphatase Shp1. In the present study, we demonstrate that Shp1 levels are markedly decreased in advanced stage CML patients compared with those in chronic phase. This process was independent of DNA methylation. Furthermore, we did not detect mutations in the Shp1 gene in CML cell lines or patient samples. These data suggest that the decrease in Shp1 in advanced stage CML patients is due to post-transcriptional modifications. Our findings suggest that the decrease in Shp1 expression levels plays a role in the progression of CML. Also, the decrease in Shp1 and subsequently its inhibitory effect on Bcr-Abl could provide an explanation for imatinib resistance seen in advanced stage CML patients.


Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva/enzimologia , Proteínas de Neoplasias/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo , Adulto , Idoso , Metilação de DNA , Análise Mutacional de DNA/métodos , DNA Complementar/genética , DNA de Neoplasias/genética , Progressão da Doença , Feminino , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/genética , Proteína Fosfatase 1 , Proteína Tirosina Fosfatase não Receptora Tipo 6/genética , RNA Mensageiro/genética , RNA Neoplásico/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos
17.
Leukemia ; 20(9): 1602-9, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16871283

RESUMO

Anaplastic lymphoma kinase (ALK)-positive anaplastic large cell lymphoma (ALK+ ALCL) is characterized by constitutive activation of the Janus kinase (JAK)3/signal transducers and activators of transcription 3 (STAT3) signaling pathway. SHP1, a tyrosine phosphatase that negatively regulates JAK/STAT, is frequently absent in ALK+ ALCL owing to gene methylation. To test the hypothesis that loss of SHP1 contributes to JAK3/STAT3 activation in ALK+ ALCL cells, we induced SHP1 expression using 5-aza-2'-deoxycytidine (5-AZA), an inhibitor of DNA methyltransferase, in ALK+ ALCL cell lines, and correlated with changes in the JAK3/STAT3 pathway. 5-AZA gradually restored SHP1 expression in Karpas 299 and SU-DHL-1 cells over 5 days. The initially low level of SHP1 expression did not result in significant changes to the expression or tyrosine phosphorylation of JAK3 and STAT3. However, higher levels of SHP1 seen subsequently correlated with substantial decreases in JAK3 and pJAK3, followed by pSTAT3 (but not STAT3). Importantly, the decrease in JAK3 was abrogated by MG132, a proteasome inhibitor. 5-AZA induced no significant increase in apoptosis but it sensitized ALCL cells to doxorubicin-induced apoptosis. Our findings support the concept that loss of SHP1 contributes to the constitutive activation of JAK3/STAT3 in ALK+ ALCL cells. SHP1 appears to downregulate JAK3 by two mechanisms: tyrosine dephosphorylation and increased degradation via the proteasome pathway.


Assuntos
Azacitidina/análogos & derivados , Regulação para Baixo/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Linfoma Difuso de Grandes Células B/metabolismo , Proteínas Tirosina Fosfatases/metabolismo , Proteínas Tirosina Quinases/metabolismo , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Quinase do Linfoma Anaplásico , Apoptose/efeitos dos fármacos , Azacitidina/farmacologia , Sequência de Bases , Western Blotting , Ciclo Celular , Linhagem Celular , Primers do DNA , Decitabina , Doxorrubicina/farmacologia , Humanos , Janus Quinase 3 , Linfoma Difuso de Grandes Células B/enzimologia , Linfoma Difuso de Grandes Células B/patologia , Proteína Tirosina Fosfatase não Receptora Tipo 6 , Receptores Proteína Tirosina Quinases
18.
Leukemia ; 19(9): 1567-72, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16049515

RESUMO

Determining the percentage of peripheral blood (PB) and bone marrow (BM) blasts is important for diagnosing and classifying acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS). Although most patients with acute leukemia or MDS have a higher percentage of BM blasts than PB blasts, the relative proportion is reversed in some patients. We explored the clinical relevance of this phenomenon in MDS (n = 446), AML (n = 1314), and acute lymphoblastic leukemia (ALL) (n = 385). Among patients with MDS or ALL, but not AML, having a higher blast percentage in PB than in BM was associated with significantly shorter survival. In multivariate analyses, these associations were independent of other relevant predictors, including cytogenetic status. Our findings suggest that MDS and ALL patients who have a higher percentage of PB blasts than BM blasts have more aggressive disease. These data also suggest that MDS classification schemes should take into account the percentage of blasts in PB differently from the percentage of blasts in BM.


Assuntos
Crise Blástica/sangue , Medula Óssea/irrigação sanguínea , Leucemia Linfoide/sangue , Leucemia Mieloide/sangue , Síndromes Mielodisplásicas/sangue , Doença Aguda , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Crise Blástica/patologia , Criança , Feminino , Humanos , Leucemia Linfoide/classificação , Leucemia Linfoide/patologia , Leucemia Mieloide/classificação , Leucemia Mieloide/patologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Síndromes Mielodisplásicas/classificação , Síndromes Mielodisplásicas/patologia , Estudos Retrospectivos , Análise de Sobrevida
20.
Leukemia ; 18(11): 1872-8, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15385932

RESUMO

Using a cDNA microarray, we found that suppressor of cytokine signaling 3 (SOCS3) is highly expressed in anaplastic lymphoma kinase (ALK)+ anaplastic large cell lymphoma (ALCL) cell lines. As SOCS3 is induced by activated signal transducer and activator of transcription 3 (STAT3), and ALK activates STAT3, we hypothesized that SOCS3 may play a role in ALK+ ALCL pathogenesis via the Janus kinase 3 (JAK3)-STAT3 pathway. Using ALCL cell lines, we show by coimmunoprecipitation experiments that SOCS3 physically binds with JAK3 in vitro, and that JAK3 inhibition by WHI-P154 downregulates SOCS3 expression. Western blot analysis confirmed expression of SOCS3 and also showed coexpression of phosphorylated (activated) STAT3 (pSTAT3). Direct sequencing of the SOCS3 gene showed no mutations or alternative splicing. In ALCL tumors that were assessed by immunohistochemistry, nine of 12 (75%) ALK+ tumors were SOCS3 positive and eight (67%) coexpressed pSTAT3. In comparison, 18 of 25 (72%) ALK-- tumors were SOCS3 positive and seven (28%) coexpressed pSTAT3. These results show that SOCS3 is overexpressed in ALCL, attributable to JAK3-STAT3 activation and likely related to ALK in ALK+ tumors. However, SOCS3 is also expressed in tumors that lack STAT3 and ALK suggesting alternative mechanisms of upregulation.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Regulação Neoplásica da Expressão Gênica , Linfoma Anaplásico de Células Grandes/metabolismo , Proteínas Tirosina Quinases/metabolismo , Proteínas Repressoras/metabolismo , Transdução de Sinais , Transativadores/metabolismo , Fatores de Transcrição/metabolismo , Processamento Alternativo , Quinase do Linfoma Anaplásico , Perfilação da Expressão Gênica , Humanos , Imunoprecipitação , Janus Quinase 3 , Linfoma Anaplásico de Células Grandes/patologia , Mutação , Análise de Sequência com Séries de Oligonucleotídeos , Fosforilação , Proteínas Tirosina Quinases/antagonistas & inibidores , Quinazolinas/farmacologia , Receptores Proteína Tirosina Quinases , Proteínas Repressoras/genética , Fator de Transcrição STAT3 , Proteína 3 Supressora da Sinalização de Citocinas , Proteínas Supressoras da Sinalização de Citocina , Fatores de Transcrição/genética , Células Tumorais Cultivadas
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