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1.
Artigo em Inglês | MEDLINE | ID: mdl-36361431

RESUMO

Parental socioeconomic position (SEP) is a known determinant of a child's health. We aimed to investigate whether a low parental education, as proxy of SEP, has a direct effect on physician-diagnosed asthma, current asthma and current allergic rhinitis in children, or whether associations are mediated by exposure to other personal or environmental risk factors. This study was a secondary data analysis of two cross-sectional studies conducted in Italy in 2006. Data from 2687 adolescents (10-14 years) were analyzed by a path analysis model using generalized structural equation modelling. Significant direct effects were found between parental education and family characteristics (number of children (coefficient = 0.6229, p < 0.001) and crowding index (1.1263, p < 0.001)) as well as with exposure to passive smoke: during pregnancy (maternal: 0.4697, p < 0.001; paternal: 0.4854, p < 0.001), during the first two years of children's life (0.5897, p < 0.001) and currently (0.6998, p < 0.001). An indirect effect of parental education was found on physician-diagnosed asthma in children mediated by maternal smoking during pregnancy (0.2350, p < 0.05) and on current allergic rhinitis mediated by early environmental tobacco smoke (0.2002; p < 0.05). These results suggest the importance of promotion of ad-hoc health policies for promoting smoking cessation, especially during pregnancy.


Assuntos
Asma , Rinite Alérgica , Rinite , Poluição por Fumaça de Tabaco , Criança , Adolescente , Masculino , Feminino , Gravidez , Humanos , Rinite/epidemiologia , Rinite/etiologia , Estudos Transversais , Asma/induzido quimicamente , Poluição por Fumaça de Tabaco/efeitos adversos , Rinite Alérgica/induzido quimicamente , Pai , Fatores de Risco
2.
Pediatr Pulmonol ; 53(6): 728-734, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29611353

RESUMO

BACKGROUND: The sweat test is one of the main diagnostic tools used in newborn screening programs and as a confirmatory test, in case of suspect of Cystic Fibrosis (CF). Since sweat chloride (Cl) concentration is also considered an appropriate parameter to explore the efficacy of CFTR modulators in clinical trials, it is crucial to evaluate the biological variability of this test in healthy and pathological conditions. The aim of this pilot study was to determine the intra-individual biological variability of sweat Cl, both in healthy individuals and CF patients and to assess its correlation with diet, season, and menstrual cycle. METHODS: Thirty-five out of 36 selected subjects (6-18 years) were enrolled by 2 CF care centers and assigned to 3 cohorts: CF, CFTR-related disorder (CFTR-RD) and healthy volunteers. Each participant was subjected to eight sweat tests in different conditions and time of the year. Data were analyzed using linear mixed effects models for repeated measures, taking also into account intra-individual correlations. RESULTS: We observed a high intra-individual variability of sweat Cl, with the lowest mean CV% values among CF patients (20.21 in CF, 29.74 in CFTR-RD, and 31.15 in healthy subjects). Gender and diet had no influence on sweat Cl variability, nor had pubertal age and menstrual phase. CONCLUSION: Results of this pilot study confirmed that sweat Cl variability is high in CF patients, although non-CF individuals displayed even higher mean CV% values. Season significantly influenced sweat test values only in CF patients, likely due to changes in their hydration status.


Assuntos
Cloretos/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Fibrose Cística/metabolismo , Suor/metabolismo , Adolescente , Variação Biológica Individual , Criança , Feminino , Voluntários Saudáveis , Humanos , Modelos Lineares , Masculino , Projetos Piloto
3.
Gynecol Oncol ; 132(2): 389-96, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24269902

RESUMO

OBJECTIVES: Reliable assessment of estrogen, progesterone (ER and PR), and HER2 receptor status are essential in breast cancer (BC) treatment. Immunohistochemical methods are limited by intra- and inter-laboratory variability. Furthermore, current methods are not the ideal approach for reproducing the biological continuum of ER, PR, and HER2 receptor levels, due to their intrinsic, semi-quantitative nature, relying in part on subjective interpretation. METHODS: In the present study, we tested a molecular approach to define ER, PR, and HER2 status in fine-needle-aspirate (FNA) samples from patients with early BC. We performed flow cytometry analysis on 88 FNA specimens from suspect BC patients to determine cellularity. We used quantitative Real Time PCR (QRT-PCR) to assess ER, PR, HER2 status, and qPCR for HER2 gene copy number (GCN). RESULTS: ER and PR mRNA levels showed a highly significant correlation with IHC data on surgical samples. qPCR showed greater accuracy than IHC in defining HER2 status. QRT-PCR defined better than IHC the continuous spectrum of the expression of the assessed receptors. Moreover, PCR analysis demonstrated a strict correlation between HER2 status and higher levels of its transcript, correctly stratifying HER2+ and HER2- patients. Finally, there was a strongly significant agreement between HER2 GCN assessed on FNA specimens by qPCR and FISH data obtained on pathological tissue specimens. CONCLUSIONS: The present results support a comprehensive approach to determine ER, PR, and HER2 status by PCR (QRT-PCR and qPCR) in FNA specimens, with high relevance for therapeutic strategies like neoadjuvant treatment.


Assuntos
Neoplasias da Mama/metabolismo , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Biomarcadores Tumorais/metabolismo , Biópsia por Agulha Fina , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Estudos de Coortes , Feminino , Citometria de Fluxo , Humanos , Imuno-Histoquímica , Estudos Prospectivos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Receptor ErbB-2/genética , Receptores de Estrogênio/genética , Receptores de Progesterona/genética
4.
Curr Cancer Drug Targets ; 13(7): 779-90, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23906053

RESUMO

Chronic myeloid leukemia (CML) is a hematological disease accounting for about 15-20% of all adult leukemias. The clinical and biologic advances achieved in such a malignancy, represent one of the best successes obtained by translational medicine. Indeed, identification of the fusion oncogene BCR-ABL has allowed using of small molecule inhibitors of its tyrosine kinase activity which, in turn, have literally revolutionized the treatment of CML. Importantly the successfully clinical management was also realized on appropriate diagnosis, disease monitoring as well as early identification of such mutations causing drug resistance. Notably the recent availability of refined laboratory equipments represented by the Next Generation Sequencing (NGS) and genomic analyses has further contributed to gain ground towards the cure of this tumor. These issues are discussed here together with an overview on how patients treated with tyrosine kinase inhibitors should be monitored.


Assuntos
Antineoplásicos/uso terapêutico , Proteínas de Fusão bcr-abl/antagonistas & inibidores , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Animais , Análise Mutacional de DNA , Monitoramento de Medicamentos , Proteínas de Fusão bcr-abl/genética , Proteínas de Fusão bcr-abl/metabolismo , Testes Genéticos , Genômica/métodos , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/enzimologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Técnicas de Diagnóstico Molecular , Terapia de Alvo Molecular , Mutação , Seleção de Pacientes , Medicina de Precisão , Valor Preditivo dos Testes , Transdução de Sinais/efeitos dos fármacos , Resultado do Tratamento
5.
Leuk Lymphoma ; 54(2): 342-52, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22762548

RESUMO

Chronic myeloid leukemia (CML) is a clonal myeloproliferative disorder characterized by the expansion of a leukemic stem cell (LSC) clone, carrying a Philadelphia translocation, able to overcome the non-malignant hematopoietic stem cells. The tyrosine kinase inhibitors (TKIs) imatinib, nilotinib and dasatinib are gold-standard for CML treatment. Each shows an impressive rate of complete cytogenetic response in chronic phase (CP)-CML. However, relapse and treatment failure are major problems with long-term use of TKIs. A polymerase chain reaction (PCR) assay to detect the mRNA expression of BCR-ABL1 represents the main molecular approach to monitoring response to treatment. However, using this analysis it is currently not possible to prospectively identify patients whose disease will relapse due to LSC reappearance. The aim of our study was to investigate whether the mRNA expression analysis of two Hedgehog (Hh) stemness signaling molecules, Smoothened (SMO) and Patched-1 (PTCH1), could predict upcoming molecular relapse. At the time of diagnosis, patients with high Sokal risk (n = 12) showed higher and lower levels of SMO and PTCH1, respectively (p = 0.0132), compared with patients with different Sokal scores (p = 0.0316 for intermediate risk and p = 0.0340 for low risk). These data suggest that Hh signaling was functionally more active in this risk group at the time of diagnosis. Furthermore, the kinetics of Hh signaling activity during the individual medical history correlated with BCR-ABL1 mRNA level and with upcoming molecular relapse. Also, mutation analysis of BCR-ABL1 revealed that activation of Hh signaling precedes molecular relapse by several months, mostly in patients carrying the gatekeeper mutation T315I. Importantly, in vitro data showed a synergistic effect of chemical inhibitors of Hh signaling and TKIs in both wild-type and resistant (T315I) CML cell lines. Collectively our data show that monitoring Hh pathway activity contemporaneously with BCR-ABL1 mRNA level may improve the chance of early detection of patients who will experience a relapse (mainly in the high Sokal risk group), paving the way for an innovative management of this hematologic malignancy.


Assuntos
Antineoplásicos/farmacologia , Proteínas Hedgehog/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Inibidores de Proteínas Quinases/farmacologia , Transdução de Sinais/efeitos dos fármacos , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/uso terapêutico , Antineoplásicos/toxicidade , Linhagem Celular Tumoral , Feminino , Proteínas de Fusão bcr-abl/genética , Regulação Leucêmica da Expressão Gênica , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/patologia , Masculino , Pessoa de Meia-Idade , Mutação , Receptores Patched , Receptor Patched-1 , Inibidores de Proteínas Quinases/uso terapêutico , Inibidores de Proteínas Quinases/toxicidade , Receptores de Superfície Celular/genética , Receptores Acoplados a Proteínas G/genética , Recidiva , Receptor Smoothened , Resultado do Tratamento , Adulto Jovem
6.
Br J Haematol ; 151(3): 252-64, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20813004

RESUMO

The present study showed that engagement of CD31 delivers a survival signal in chronic lymphocytic leukaemia (CLL) cells. We describe two groups of CLL, showing different kinetics of apoptosis in vitro and distinct ratios between anti-apoptotic and pro-apoptotic proteins: CLL-I displayed low Bcl-x(L) /Bax and Bcl-2/Bax ratio and underwent rapid apoptosis in vitro; CLL-II had high Bcl-x(L) /Bax and Bcl-2/Bax ratio and were resistant to apoptosis for several days. Nurse-like cells, expressing vimentin, CD68 and CD31 were detected mainly in CLL-II cultures. Of note, CD31 cross-linking, obtained with a specific monoclonal antibody (mAb), induced phosphatidylinositol-3-kinase-dependent Akt phosphorylation and nuclear translocation of the nuclear factor-kBp65 and p52 subunits in both CLL groups, leading to upregulation of Bcl-2 and Bcl-x(L) transcription and increased cell survival. Binding to CD31(+) stable transfectants, could also deliver an anti-apoptotic signal in B cells of both CLL-I and CLL-II, increasing the Bcl-2 and Bcl-x(L) protein content, regardless the expression of CD38. On the other hand, the addition of the F(ab')2 (that is unable to oligomerize the target molecule) of the anti-CD31 mAb prevented these effects. These data suggest that the CD31 adhesion system may play a role also in vivo in maintaining CLL survival.


Assuntos
Leucemia Linfocítica Crônica de Células B/metabolismo , Molécula-1 de Adesão Celular Endotelial a Plaquetas/fisiologia , ADP-Ribosil Ciclase 1/metabolismo , Idoso , Idoso de 80 Anos ou mais , Anticorpos Heterófilos/fisiologia , Apoptose/fisiologia , Adesão Celular/fisiologia , Sobrevivência Celular/fisiologia , Feminino , Humanos , Leucemia Linfocítica Crônica de Células B/patologia , Masculino , Glicoproteínas de Membrana/metabolismo , Pessoa de Meia-Idade , Proteínas de Neoplasias/metabolismo , Transdução de Sinais/fisiologia , Células Tumorais Cultivadas
8.
Bioorg Med Chem ; 18(9): 3320-34, 2010 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-20346684

RESUMO

Novel alpha-mannosidase inhibitors of the type (2R,3R,4S)-2-({[(1R)-2-hydroxy-1-arylethyl]amino}methyl)pyrrolidine-3,4-diol have been prepared and assayed for their anticancer activities. Compound 30 with the aryl group=4-trifluoromethylbiphenyl inhibits the proliferation of primary cells and cell lines of different origins, irrespective of Bcl-2 expression levels, inducing a G2/Mcell cycle arrest and by modification of genes involved in cell cycle progression and survival.


Assuntos
Neoplasias Hematológicas , Neoplasias , Teprotida , alfa-Manosidase/antagonistas & inibidores , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Estrutura Molecular , Teprotida/síntese química , Teprotida/química , Teprotida/farmacologia
9.
Curr Cancer Drug Targets ; 10(2): 168-75, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20088787

RESUMO

Lapatinib, a dual HER2 and EGFR tyrosine kinase inhibitor is highly active in HER2+ breast cancer. However, its efficacy is limited by either primary or acquired resistance. Although mutations in ras genes are rarely found in breast cancer, H-ras overexpression is frequently observed. Moreover, genetic alterations that do not directly involve ras such as Brk amplification, ultimately result in increased ras signaling. Using SKBR3 cells, a HER2+ breast cancer cell line that is naturally devoid of mutations in PI3KCA, PTEN, BRAF, and ras we show that both H-ras overexpression and expression of an oncogenic ras allele (ras V12) reduce susceptibility to lapatinib in analogy to what observed with activating PI3KCA mutations and with a constitutively active form of Akt. Importantly, we found that resistance to lapatinib due to ras overexpression or to ras V12 is overcome by MEK inhibition with U0126, suggesting a key role for the MEK-Erk pathway in ras-induced resistance. Similar results were obtained in BT474 cells, another HER+ breast cancer cell line. Therefore, our data indicate that overexpressed/mutated ras may act as a biological modifier of the response to lapatinib. Combining MEK inhibitors with lapatinib may help overcome this form of resistance and increase the efficacy of lapatinib in these tumors.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos , Genes ras/efeitos dos fármacos , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Quinazolinas/farmacologia , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Butadienos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Transformação Celular Neoplásica/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Feminino , Genes ras/fisiologia , Humanos , Immunoblotting , Lapatinib , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Mutação/genética , Nitrilas/farmacologia , Receptor ErbB-2/metabolismo , Transdução de Sinais
10.
Leuk Lymphoma ; 51(2): 275-8, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20038234

RESUMO

Acquired resistance to imatinib in the advanced phase of chronic myeloid leukemia (CML) has been associated with mutations in the kinase domain (KD) of BCR-ABL. On the contrary, the prognostic implication of KD mutations in early chronic phase (CP) patients at diagnosis before imatinib-based therapy has not yet been established. We have reviewed the status of mutations in 43 patients with early CP-CML on the samples collected at diagnosis. Mutations were identified by direct sequencing (DS) with BidDye Terminator v 1.1. cycle sequencing kit and analyzed with a 3130 ABI capillary electrophoresis system. Eight out 13 (61.5%) high Sokal risk patients showed the following mutations: Y253C, S265R, E255K, F359Y, N374S, E255V, E255V, E255V. Three patients progressed during imatinib and second-line inhibitors and died of blastic phase CML at 23, 33, and 69 months. Another patient with intermediate Sokal risk showed D363G mutation at diagnosis, progressed under imatinib, was allografted and he is now alive in major molecular remission (MMR). No low-risk patient carried KD mutation at diagnosis. In conclusion, KD mutations conferring high-level imatinib resistance are present in patients with de novo CML and in some of them lead to disease progression.


Assuntos
Proteínas de Fusão bcr-abl/genética , Leucemia Mieloide de Fase Crônica/tratamento farmacológico , Mutação , Piperazinas/uso terapêutico , Pirimidinas/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Benzamidas , Análise Mutacional de DNA , Progressão da Doença , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Humanos , Mesilato de Imatinib , Leucemia Mieloide de Fase Crônica/diagnóstico , Leucemia Mieloide de Fase Crônica/genética , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Inibidores de Proteínas Quinases/uso terapêutico , Adulto Jovem
12.
Cancer Genet Cytogenet ; 177(2): 115-9, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17854665

RESUMO

Chromosomal translocations involving the 12q14 band are rarely detected in hematological disorders, and are usually correlated with HMGA2 gene expression. HMGA2 is highly expressed during embryonic cell growth and differentiation, and regulates transcription and chromatin organization, but is rarely detectable in adult tissues. We describe a case of polycythemia vera with a t(12;21)(q14;q22). The 12q14 breakpoint was characterized by fluorescence in situ hybridization analysis using the bacterial artificial chromosome RP11-366L20 containing 3' sequences of the HMGA2 gene. Qualitative and quantitative polymerase chain reaction showed the presence of high levels of HMGA2 gene expression, which were temporarily reduced with hydroxyurea therapy. The present case confirms that involvement of the 12q14 band may be associated with HMGA2 overexpression in chronic Philadelphia chromosome-negative myeloproliferative disease, regardless of the partner chromosome involved in the translocation. Such overexpression may contribute to the pathogenesis of the disease, which otherwise of itself shows a favorable and stable course.


Assuntos
Cromossomos Humanos Par 12/genética , Cromossomos Humanos Par 21/genética , Proteína HMGA2/genética , Cromossomo Filadélfia , Policitemia Vera/genética , Translocação Genética , Idoso , Bandeamento Cromossômico , Feminino , Humanos , Hibridização in Situ Fluorescente , Cariotipagem , Transcrição Gênica
13.
Eur J Immunol ; 36(3): 681-9, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16479541

RESUMO

Proteasome inhibitors possess potent antitumor activity against a broad spectrum of human malignancies. However, the effects of these compounds on the immune system still have to be clearly determined. In the present study, we have investigated the effects of proteasome inhibitors on dendritic cells (DC), antigen-presenting cells playing a key role in the initiation of immune responses. Exposure to the proteasome inhibitors bortezomib, MG132 or epoxomicin was found to promote apoptosis of human monocyte-derived DC and to reduce the yield of viable DC when given to monocytes early during differentiation to DC. DC apoptosis via proteasome inhibition was accompanied by mitochondria disruption and subsequent activation of the caspase cascade. Up-regulation and intracellular redistribution of Bcl-2-associated X protein (Bax), a pro-apoptotic Bcl-2 family protein, were observed in DC treated with these compounds and represent a suitable mechanism leading to activation of the intrinsic apoptotic pathway. Finally, active protein synthesis was found to represent an upstream prerequisite for DC apoptosis induced by proteasome inhibitors, since the translation inhibitor cycloheximide blocked all of the steps of the observed apoptotic response. In conclusion, induction of apoptosis in DC may represent a novel mechanism by which proteasome inhibitors affect the immune response at the antigen-presenting cell level.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Células Dendríticas/imunologia , Monócitos/imunologia , Inibidores de Proteases/farmacologia , Inibidores de Proteassoma , Apoptose/imunologia , Células Cultivadas , Células Dendríticas/citologia , Humanos , Mitocôndrias/imunologia , Monócitos/citologia , Complexo de Endopeptidases do Proteassoma/imunologia , Biossíntese de Proteínas/efeitos dos fármacos , Biossíntese de Proteínas/imunologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/imunologia , Proteína X Associada a bcl-2/imunologia
14.
Blood ; 105(8): 3255-62, 2005 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-15613543

RESUMO

Proteasome inhibitors exhibit antitumor activity against malignancies of different histology. Yet, the mechanisms underlying this effect are poorly understood. Recent evidence indicates that antiapoptotic factors may also accumulate as a consequence of exposure to these drugs, possibly reducing their cytotoxicity. These include the Bcl-2 family member Mcl-1, whose down-regulation has been proposed to initiate apoptosis in response to genotoxic stimuli. In this study, we found that proteasome inhibitors release cyotochrome c and second mitochondria-derived activator of caspase (SMAC)/Diablo and trigger the subsequent apoptotic cascade in spite of concomitant Mcl-1 increase. However, our data indicate that subtraction of Mcl-1 during apoptosis, although not required for early release of proapoptotic factors, is probably relevant in speeding up cell demise, since RNA interference-mediated Mcl-1 silencing is lethal in lymphoma cells. Consistent with this, the cytotoxic effects of proteasome inhibitors are enhanced when Mcl-1 increase is impeded. Thus, this study identifies Mcl-1 accumulation as an unwanted molecular consequence of exposure to proteasome inhibitors, which slows down their proapoptotic effects. Pharmacologic or genetic approaches targeting Mcl-1, including therapeutic RNAi, may increase the effectiveness of these compounds.


Assuntos
Acetilcisteína/análogos & derivados , Apoptose/fisiologia , Linfócitos/fisiologia , Proteínas de Neoplasias/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Inibidores de Proteassoma , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Acetilcisteína/farmacologia , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose , Proteínas de Transporte/metabolismo , Caspases/metabolismo , Sobrevivência Celular/imunologia , Complexo de Ataque à Membrana do Sistema Complemento , Proteínas do Sistema Complemento , Inibidores de Cisteína Proteinase/farmacologia , Citocromos c/metabolismo , Expressão Gênica/imunologia , Glicoproteínas/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Células Jurkat , Leupeptinas/farmacologia , Linfócitos/citologia , Linfócitos/efeitos dos fármacos , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Proteína de Sequência 1 de Leucemia de Células Mieloides , Proteínas de Neoplasias/genética , Oligopeptídeos/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Interferência de RNA
15.
Clin Cancer Res ; 10(4): 1463-70, 2004 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-14977850

RESUMO

PURPOSE: Overexpression of antiapoptotic Bcl-2 family members has recently been related to resistance to chemo/radiotherapy in several human malignancies, particularly lymphomas. Hence, innovative approaches bypassing this resistance mechanism are required in the therapeutic approach. This study evaluated whether chemoresistance associated with Bcl-2 and Bcl-x(L) overexpression would be overcome by activating the death receptor pathway by tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) in the Jurkat cell model EXPERIMENTAL DESIGN: We made use of genetically modified Jurkat cells to evaluate the effect of Bcl-2 or Bcl-x(L) overexpression on the cytotoxic effect produced by the anticancer drugs doxorubicin, etoposide, and oxaliplatin and TRAIL. Caspase activation was detected by cleavage of caspase-8 and -3. The mitochondrial transmambrane potential was assessed by staining with DiOC(6) and flow cytometry. Caspase activity was blocked by the broad-spectrum caspase inhibitor zVAD-fmk. RESULTS: Bcl-2 and Bcl-x(L) overexpression but not lack of caspase-8 protects the Jurkat cells from the anticancer drug-induced cytolysis. However, Bcl-2/Bcl-x(L) Jurkat cells retained some susceptibility to TRAIL-induced cytolysis. A highly synergistic cytotoxic effect of the combination of TRAIL with any of the antiblastic used in this study was detected in the chemoresistant cells. This effect was associated with mitochondrial disassemblage and dependent on caspase activation CONCLUSIONS: The combination of TRAIL with conventional anticancer drugs may prove to be useful in the treatment of antiapoptotic Bcl-2 family proteins-expressing malignancies.


Assuntos
Antineoplásicos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Glicoproteínas de Membrana/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Clorometilcetonas de Aminoácidos/farmacologia , Proteínas Reguladoras de Apoptose , Caspase 3 , Caspase 8 , Caspases/metabolismo , Relação Dose-Resposta a Droga , Doxorrubicina/farmacologia , Ativação Enzimática , Etoposídeo/farmacologia , Citometria de Fluxo , Humanos , Immunoblotting , Células Jurkat , Ligantes , Linfoma/metabolismo , Potenciais da Membrana , Compostos Organoplatínicos/farmacologia , Oxaliplatina , Ligante Indutor de Apoptose Relacionado a TNF , Fatores de Tempo , Proteína bcl-X
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