RESUMO
Acute myeloid leukemia (AML) is frequently linked to genetic abnormalities, with the t (8; 21) translocation, resulting in the production of a fusion oncoprotein AML1-ETO (AE), being a prevalent occurrence. This protein plays a pivotal role in t (8; 21) AML's onset, advancement, and recurrence, making it a therapeutic target. However, the development of drug molecules targeting AML1-ETO are markedly insufficient, especially used in clinical treatment. In this study, it was uncovered that Neratinib could significantly downregulate AML1-ETO protein level, subsequently promoting differentiation of t (8; 21) AML cells. Based on "differentiated active" probes, Neratinib was identified as a functional inhibitor against HNRNPA3 through covalent binding. The further studies demonstrated that HNRNPA3 function as a putative m6A reader responsible for recognizing and regulating the alternative splicing of AML-ETO pre-mRNA. These findings not only contribute to a novel insight to the mechanism governing post-transcriptional modification of AML1-ETO transcript, but also suggest that Neratinib would be promising therapeutic potential for t (8; 21) AML treatment.
Assuntos
Diferenciação Celular , Subunidade alfa 2 de Fator de Ligação ao Core , Leucemia Mieloide Aguda , Proteínas de Fusão Oncogênica , Quinolinas , Proteína 1 Parceira de Translocação de RUNX1 , Humanos , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/metabolismo , Quinolinas/farmacologia , Diferenciação Celular/efeitos dos fármacos , Proteína 1 Parceira de Translocação de RUNX1/genética , Proteína 1 Parceira de Translocação de RUNX1/metabolismo , Precursores de RNA/metabolismo , Precursores de RNA/genética , Ribonucleoproteínas Nucleares Heterogêneas Grupo A-B/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas Grupo A-B/genética , Translocação Genética/efeitos dos fármacos , Adenosina/análogos & derivados , Adenosina/metabolismo , Adenosina/farmacologia , Processamento Alternativo/efeitos dos fármacos , Linhagem Celular Tumoral , Animais , CamundongosRESUMO
B-cell non-Hodgkin lymphoma (NHL) is among the ten most common malignancies. Survival rates range from very poor to over 90% and highly depend on the stage and subtype. Characteristic features of NHL are recurrent translocations juxtaposing an oncogene (e.g. MYC, BCL2) to the enhancers in the immunoglobulin heavy chain (IGH) locus. Survival and proliferation of many B-cell lymphomas depend on the expression of the translocated oncogene. Thus, targeting IGH enhancers as an anti-lymphoma treatment seems a promising strategy. Recently, a small molecule - 7-[[(4-methyl-2-pyridinyl)amino](2-pyridinyl)methyl]-8-quinolinol (compound 30666) was identified to decrease activity of the Eµ enhancer and reduce the expression of translocated oncogenes in multiple myeloma and some NHL cell lines (Dolloff, 2019). Here, we aimed to test the effect of compound 30666 in Burkitt lymphoma (BL) and diffuse large B-cell lymphoma (DLBCL) and shed light on its mechanism of action. We report that both IGH-translocation positive NHL cells as well as IGH-translocation negative B cells and non-B cell controls treated with compound 30666 exhibited consistent growth inhibition. A statistically significant increase in cell percentage in sub-G1 phase of cell cycle was observed, suggesting induction of apoptosis. Compound 30666 downregulated MYC levels in BL cell lines and altered IGH enhancer RNA expression. Moreover, a global decrease of H3K27ac and an increase of H3K4me1 was observed upon 30666 treatment, which suggests switching enhancers to a poised or primed state. Altogether, our findings indicate that 30666 inhibitor affects enhancer activity but might not be as specific for IGH enhancers as previously reported.
Assuntos
Linfoma de Burkitt/tratamento farmacológico , Elementos Facilitadores Genéticos/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Hidroxiquinolinas/farmacologia , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Piridinas/farmacologia , Translocação Genética/efeitos dos fármacos , Linfoma de Burkitt/genética , Linfoma de Burkitt/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Ensaios de Seleção de Medicamentos Antitumorais , Código das Histonas/efeitos dos fármacos , Humanos , Hidroxiquinolinas/uso terapêutico , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/patologia , Piridinas/uso terapêuticoRESUMO
Fructans such as fructo-oligosaccharides (FOS) and inulin have been reported to directly regulate ileal inflammatory responses in lipopolysaccharide (LPS)-induced endotoxemic mice, without alterations in the colonic microbiota. Firstly, we replicated this model and found that a single gavage of 10 mg g-1 of fructans directly promoted caecal acetate and propionate production. Thus, the previous understanding of microbiota-independent effects of prebiotic fructans in endotoxemic mice has been challenged. In parallel, we performed a daily gavage of 160 mg kg-1 of inulin, xylan, or Dendrobium officinale polysaccharides (DOP) for two weeks prior to LPS injection. The long-term intake of prebiotic fibres reduced the bacterial load in the spleen and mesenteric lymph nodes (MLNs), and in comparison, a single gavage of fructans increased that. However, the long-term intake was unable to improve the short-chain fatty acid (SCFA) synthesis and epithelial barrier function that were impaired by LPS. Notably, the three fibre types consistently reduced the expression of mucin 2 (MUC2) and variously modulated critical mediators (IL-18, IL-22, and HIF-1α) to regulate the host-commensal microbiota interactions in the ileum. In addition, the three fibre types consistently inhibited the inflammatory T helper (Th) cell response in the ileum, while they diversely modulated the peripheral and systemic Th cell responses. Overall, the prebiotic fibres displayed microbiota-related changes in endotoxemic mice, and the potential associations with the in vivo anti-inflammatory effects of prebiotic fibres need further investigation.
Assuntos
Endotoxemia/metabolismo , Ácidos Graxos Voláteis/metabolismo , Microbioma Gastrointestinal/efeitos dos fármacos , Íleo/metabolismo , Prebióticos/administração & dosagem , Translocação Genética/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Lipopolissacarídeos , Camundongos , Camundongos Endogâmicos C57BLRESUMO
Venetoclax is a highly potent, selective BCL2 inhibitor capable of inducing apoptosis in cells dependent on BCL2 for survival. Most myeloma is MCL1-dependent; however, a subset of myeloma enriched for translocation t(11;14) is codependent on BCL2 and thus sensitive to venetoclax. The biology underlying this heterogeneity remains poorly understood. We show that knockdown of cyclin D1 does not induce resistance to venetoclax, arguing against a direct role for cyclin D1 in venetoclax sensitivity. To identify other factors contributing to venetoclax response, we studied a panel of 31 myeloma cell lines and 25 patient samples tested for venetoclax sensitivity. In cell lines, we corroborated our previous observation that BIM binding to BCL2 correlates with venetoclax response and further showed that knockout of BIM results in decreased venetoclax sensitivity. RNA-sequencing analysis identified expression of B-cell genes as enriched in venetoclax-sensitive myeloma, although no single gene consistently delineated sensitive and resistant cells. However, a panel of cell surface makers correlated well with ex vivo prediction of venetoclax response in 21 patient samples and may serve as a biomarker independent of t(11;14). Assay for transposase-accessible chromatin sequencing of myeloma cell lines also identified an epigenetic program in venetoclax-sensitive cells that was more similar to B cells than that of venetoclax-resistant cells, as well as enrichment for basic leucine zipper domain-binding motifs such as BATF. Together, these data indicate that remnants of B-cell biology are associated with BCL2 dependency and point to novel biomarkers of venetoclax-sensitive myeloma independent of t(11;14).
Assuntos
Linfócitos B/metabolismo , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Epigênese Genética/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Mieloma Múltiplo , Sulfonamidas/farmacologia , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Linhagem Celular Tumoral , Cromossomos Humanos Par 11/genética , Cromossomos Humanos Par 11/metabolismo , Cromossomos Humanos Par 14/genética , Cromossomos Humanos Par 14/metabolismo , Ciclina D1/genética , Ciclina D1/metabolismo , Técnicas de Silenciamento de Genes , Humanos , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/genética , Mieloma Múltiplo/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Translocação Genética/efeitos dos fármacosRESUMO
Mutations in the glucocerebrosidase gene (GBA) encoding the lysosomal enzyme glucocerebrosidase (GCase) cause Gaucher disease (GD) and are the most commonly known genetic risk factor for Parkinson disease (PD). Ambroxol is one of the most effective pharmacological chaperones of GCase. Fourteen GD patients, six PD patients with mutations in the GBA gene (GBA-PD), and thirty controls were enrolled. GCase activity and hexosylsphingosine (HexSph) concentration were measured in dried blood and macrophage spots using liquid chromatography coupled with tandem mass spectrometry. The effect of ambroxol on GCase translocation to lysosomes was assessed using confocal microscopy. The results showed that ambroxol treatment significantly increased GCase activity in cultured macrophages derived from patient blood monocytic cell (PBMC) of GD (by 3.3-fold) and GBA-PD patients (by 3.5-fold) compared to untreated cells (p < 0.0001 and p < 0.0001, respectively) four days after cultivation. Ambroxol treatment significantly reduced HexSph concentration in GD (by 2.1-fold) and GBA-PD patients (by 1.6-fold) (p < 0.0001 and p < 0.0001, respectively). GD macrophage treatment resulted in increased GCase level and increased enzyme colocalization with the lysosomal marker LAMP2. The possible binding modes of ambroxol to mutant GCase carrying N370S amino acid substitution at pH 4.7 were examined using molecular docking and molecular dynamics simulations. The ambroxol position characterized by minimal binding free energy was observed in close vicinity to the residue, at position 370. Taken together, these data showed that PBMC-derived macrophages could be used for assessing ambroxol therapy response for GD patients and also for GBA-PD patients.
Assuntos
Ambroxol/farmacologia , Inibidores Enzimáticos/farmacologia , Doença de Gaucher/tratamento farmacológico , Glucosilceramidase/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Chaperonas Moleculares/farmacologia , Doença de Parkinson/tratamento farmacológico , Translocação Genética/efeitos dos fármacos , Adulto , Idoso , Idoso de 80 Anos ou mais , Células Cultivadas , Feminino , Glucosilceramidase/antagonistas & inibidores , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Venetoclax is efficacious in relapsed/refractory t(11;14) multiple myeloma, thus warranting investigation in light-chain amyloidosis (AL). This retrospective cohort includes 43 patients with previously treated AL, from 14 centers in the US and Europe. Thirty-one patients harbored t(11;14), 11 did not, and one t(11;14) status was unknown. Patients received a venetoclax-containing regimen for at least one 21- or 28-day cycle; the median prior treatments was three. The hematologic response rate for all patients was 68%; 63% achieved VGPR/CR. t(11;14) patients had higher hematologic response (81% vs. 40%) and higher VGPR/CR rate (78% vs. 30%, odds ratio: 0.12, 95% CI 0.02-0.62) than non-t(11;14) patients. For the unsegregated cohort, median progression-free survival (PFS) was 31.0 months and median OS was not reached (NR). For t(11;14), median PFS was NR and for non-t(11;14) median PFS was 6.7 months (HR: 0.14, 95% CI 0.04-0.53). Multivariate analysis incorporating age, sex, prior lines of therapy, and disease stage suggested a risk reduction for progression or death in t(11;14) patients. Median OS was NR for either subgroup. The organ response rate was 38%; most responders harbored t(11;14). Grade 3 or higher adverse events occurred in 19% with 7% due to infections. These promising results require confirmation in a randomized clinical trial.
Assuntos
Antineoplásicos/uso terapêutico , Compostos Bicíclicos Heterocíclicos com Pontes/uso terapêutico , Amiloidose de Cadeia Leve de Imunoglobulina/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Sulfonamidas/uso terapêutico , Idoso , Feminino , Humanos , Amiloidose de Cadeia Leve de Imunoglobulina/genética , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/genética , Intervalo Livre de Progressão , Estudos Retrospectivos , Translocação Genética/efeitos dos fármacos , Resultado do TratamentoRESUMO
The purpose of the present investigation is to analyze the in vivo genotoxicity dose-response data of ethylene oxide (EO) and the applicability of the derived point-of-departure (PoD) values when estimating permitted daily exposure (PDE) values. A total of 40 data sets were identified from the literature, and benchmark dose analyses were conducted using PROAST software to identify a PoD value. Studies employing the inhalation route of exposure and assessing gene or chromosomal mutations and chromosomal damage in various tissues were considered the most relevant for assessing risk from EO, since these effects are likely to contribute to adverse health consequences in exposed individuals. The PoD estimates were screened for precision and the values were divided by data-derived adjustment factors. For gene mutations, the lowest PDE was 285 parts per trillion (ppt) based on the induction of lacI mutations in the testes of mice following 48 weeks of exposure to EO. The corresponding lowest PDE value for chromosomal mutations was 1,175 ppt for heritable translocations in mice following 8.5 weeks of EO exposure. The lowest PDE for chromosomal aberrations was 238 ppt in the mouse peripheral blood lymphocytes following 48 weeks of inhalation exposure. The diverse dose-response data for EO-induced genotoxicity enabled the derivation of PoDs for various endpoints, tissues, and species and identified 238 ppt as the lowest PDE in this retrospective analysis.
Assuntos
Óxido de Etileno/toxicidade , Mutagênicos/toxicidade , Animais , Aberrações Cromossômicas/efeitos dos fármacos , Relação Dose-Resposta a Droga , Óxido de Etileno/administração & dosagem , Camundongos , Testes de Mutagenicidade , Mutagênicos/administração & dosagem , Mutação/efeitos dos fármacos , Ratos , Medição de Risco , Translocação Genética/efeitos dos fármacosRESUMO
Cytogenetic abnormalities are found in most multiple myeloma (MM) patients. Although their prognostic value has been well studied, there are limited data on the association of primary cytogenetic abnormalities with disease characteristics and treatment response. This study was designed to evaluate these associations. This is a retrospective study including 2027 Mayo Clinic patients diagnosed with MM between February 2004 and February 2018 who had cytogenetic testing by FISH at diagnosis. Translocations t(4;14), t(14;16), t(6;14), and t(14;20) were associated with anemia, beta2microglobulin >5.5 µg/ml and ≥50% bone marrow plasma cells; t(4;14) was associated with higher serum monoclonal protein and plasma cell proliferation. Overall response rate to proteasome inhibitor (PI)-based treatment was higher for IgH translocations compared to trisomies (83% vs. 71%, P = 0.002), but was higher for trisomies with immunomodulatory drug (IMiD)-based treatment (87% vs. 75%, P < 0.001). Time to next treatment was longer with trisomies than IgH translocation with IMiD-based (32.1 vs. 18.4 months, P < 0.001) and PI + IMiD-based (44.0 vs. 27.4 months, P = 0.003) treatments. Outcomes were superior with PI + IMiD combinations in all groups. Our results show that t(4;14), t(14;16), t(6;14), and t(14;20) are associated with high-risk disease characteristics, and IgH translocations and trisomies may be associated with better responses to PIs and IMiDs, respectively.
Assuntos
Fatores Imunológicos/uso terapêutico , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/genética , Inibidores de Proteassoma/uso terapêutico , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Aberrações Cromossômicas/efeitos dos fármacos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/diagnóstico , Prognóstico , Estudos Retrospectivos , Translocação Genética/efeitos dos fármacos , Resultado do Tratamento , Trissomia/genéticaRESUMO
Chromosomal NUP98-PHF23 translocation is associated with an aggressive form of acute myeloid leukemia (AML) and poor survival rate. Here, we report the molecular mechanisms by which NUP98-PHF23 recognizes the histone mark H3K4me3 and is inhibited by small molecule compounds, including disulfiram that directly targets the PHD finger of PHF23 (PHF23PHD). Our data support a critical role for the PHD fingers of NUP98-PHF23, and related NUP98-KDM5A and NUP98-BPTF fusions in driving leukemogenesis, and demonstrate that blocking this interaction in NUP98-PHF23 expressing AML cells leads to cell death through necrotic and late apoptosis pathways. An overlap of NUP98-KDM5A oncoprotein binding sites and H3K4me3-positive loci at the Hoxa/b gene clusters and Meis1 in ChIP-seq, together with NMR analysis of the H3K4me3-binding sites of the PHD fingers from PHF23, KDM5A and BPTF, suggests a common PHD finger-dependent mechanism that promotes leukemogenesis by this type of NUP98 fusions. Our findings highlight the direct correlation between the abilities of NUP98-PHD finger fusion chimeras to associate with H3K4me3-enriched chromatin and leukemic transformation.
Assuntos
Cromatina/metabolismo , Proteínas de Homeodomínio/metabolismo , Leucemia Mieloide/metabolismo , Complexo de Proteínas Formadoras de Poros Nucleares/metabolismo , Proteínas de Fusão Oncogênica/metabolismo , Doença Aguda , Antígenos Nucleares/genética , Antígenos Nucleares/metabolismo , Cromatina/genética , Dissulfiram/farmacologia , Histonas/metabolismo , Proteínas de Homeodomínio/genética , Humanos , Leucemia Mieloide/genética , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Complexo de Proteínas Formadoras de Poros Nucleares/genética , Proteínas de Fusão Oncogênica/genética , Dedos de Zinco PHD/genética , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Proteína 2 de Ligação ao Retinoblastoma/genética , Proteína 2 de Ligação ao Retinoblastoma/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Translocação Genética/efeitos dos fármacos , Translocação Genética/genéticaAssuntos
Antineoplásicos/uso terapêutico , Compostos Bicíclicos Heterocíclicos com Pontes/uso terapêutico , Amiloidose de Cadeia Leve de Imunoglobulina/tratamento farmacológico , Sulfonamidas/uso terapêutico , Translocação Genética/efeitos dos fármacos , Idoso , Feminino , Humanos , Amiloidose de Cadeia Leve de Imunoglobulina/genética , Masculino , Pessoa de Meia-Idade , Resultado do TratamentoRESUMO
BACKGROUND: It has been confirmed that NF-κB p65 signaling pathway is involved in the regulation of alveolar hypercoagulation and fibrinolysis inhibition in acute respiratory distress syndrome (ARDS). Whether SN50, a NF-κB cell permeable inhibitor, could attenuate alveolar hypercoagulation and fibrinolysis inhibition in ARDS remains to be elucidated. PURPOSE: We explored the efficacy and potential mechanism of SN50 on alveolar hypercoagulation and fibrinolysis inhibition in ARDS in mice. MATERIALS AND METHODS: Mouse ARDS was made by 50 µl of lipopolysaccharide (LPS) (4 mg/ml) inhalation. Male BALB/c mice were intraperitoneally injected with different does of SN50 1 h before LPS inhalation. Lung tissues were collected for hematoxylin-eosin (HE) staining, wet/dry ratio. Pulmonary expressions of tissue factor (TF), plasminogen activator inhibitor-1 (PAI-1), collagen III, as well as phosphorylated p65 (p-p65), p65 in nucleus (p'-p65), IκBα and IKKα/ß were measured. Bronchoalveolar lavage fluid (BALF) was gathered to test the concentrations of TF, PAI-1, activated protein C (APC) and thrombinantithrombin complex (TAT). DNA binding activity of NF-κB p65 was also determined. RESULTS: After LPS stimulation, pulmonary edema and exudation and alveolar collapse occured. LPS also stimulated higher expressions of TF and PAI-1 in lung tissues, and higher secretions of TF, PAI-1, TAT and low level of APC in BALF. Pulmonary collagen III expression was obviously enhanced after LPS inhalation. At same time, NF-κB signaling pathway was activated with LPS injury, shown by higher expressions of p-p65, p'-p65, p-IKKα/ß, p-Iκα in pulmonary tissue and higher level p65 DNA binding activity. SN50 dose-dependently inhibited TF, PAI-1 and collagen IIIexpressions, and decreased TF, PAI-1, TAT but increased APC in BALF. SN50 treatment attenuated pulmonary edema, exudation and reduced lung tissue damage as well. SN50 application significantly reduced p'-p65 expression and weakened p65 DNA binding activity, but expressions of p-p65, p-IKKα/ß, p-Iκα in cytoplasm of pulmonary tissue were not affected. CONCLUSIONS: SN 50 attenuates alveolar hypercoagulation and fibrinolysis inhibition in ARDS via inhibition of NF-κB p65 translocation. Our data demonstrates that NF-κB p65 pathway is a viable new therapeutic target for ARDS treatment.
Assuntos
Fibrinólise/efeitos dos fármacos , Peptídeos/uso terapêutico , Síndrome do Desconforto Respiratório/tratamento farmacológico , Trombofilia/tratamento farmacológico , Fator de Transcrição RelA/antagonistas & inibidores , Translocação Genética/efeitos dos fármacos , Animais , Fibrinólise/fisiologia , Lipopolissacarídeos/toxicidade , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Peptídeos/farmacologia , Alvéolos Pulmonares/efeitos dos fármacos , Alvéolos Pulmonares/metabolismo , Distribuição Aleatória , Síndrome do Desconforto Respiratório/induzido quimicamente , Síndrome do Desconforto Respiratório/metabolismo , Trombofilia/induzido quimicamente , Trombofilia/metabolismo , Fator de Transcrição RelA/metabolismo , Translocação Genética/fisiologiaRESUMO
Bioflavonoids have a similar chemical structure to etoposide, the well-characterized topoisomerase II (Top2) poison, and evidence shows that they also induce DNA double-strand breaks (DSBs) and promote genome rearrangements. The purpose of this study was to determine the kinetics of bioflavonoid-induced DSB appearance and repair, and their dependence on Top2. Cells were exposed to bioflavonoids individually or in combination in the presence or absence of the Top2 catalytic inhibitor dexrazoxane. The kinetics of appearance and repair of γH2AX foci were measured. In addition, the frequency of resultant MLL-AF9 breakpoint cluster region translocations was determined. Bioflavonoids readily induced the appearance of γH2AX foci, but bioflavonoid combinations did not act additively or synergistically to promote DSBs. Myricetin-induced DSBs were mostly reduced by dexrazoxane, while genistein and quercetin-induced DSBs were only partially, but significantly, reduced. By contrast, luteolin and kaempferol-induced DSBs increased with dexrazoxane pre-treatment. Sensitivity to Top2 inhibition correlated with a significant reduction of bioflavonoid-induced MLL-AF9 translocations. These data demonstrate that myricetin, genistein, and quercetin act most similar to etoposide although with varying Top2-dependence. By contrast, luteolin and kaempferol have distinct kinetics that are mostly Top2-independent. These findings have implications for understanding the mechanisms of bioflavonoid activity and the potential of individual bioflavonoids to promote chromosomal translocations. Further, they provide direct evidence that specific Top2 inhibitors or targeted drugs could be developed that possess less leukemic potential or suppress chromosomal translocations associated with therapy-related and infant leukemias.
Assuntos
Reparo do DNA/efeitos dos fármacos , Flavonoides/toxicidade , Genisteína/toxicidade , Quempferóis/toxicidade , Luteolina/toxicidade , Quercetina/toxicidade , Animais , Linhagem Celular , Pontos de Quebra do Cromossomo/efeitos dos fármacos , Cromossomos de Mamíferos/efeitos dos fármacos , DNA/química , Quebras de DNA de Cadeia Dupla/efeitos dos fármacos , DNA Topoisomerases Tipo II/genética , DNA Topoisomerases Tipo II/metabolismo , Dexrazoxano/farmacologia , Etoposídeo/toxicidade , Histonas/genética , Histonas/metabolismo , Camundongos , Células-Tronco Embrionárias Murinas/efeitos dos fármacos , Células-Tronco Embrionárias Murinas/metabolismo , Células-Tronco Embrionárias Murinas/ultraestrutura , Inibidores da Topoisomerase II/farmacologia , Translocação Genética/efeitos dos fármacosRESUMO
Idiosyncratic drug-induced liver injury (IDILI) is a severe disease that cannot be detected during drug development. It has been shown that hepatotoxicity of some compounds associated with IDILI becomes apparent when these are combined in vivo and in vitro with LPS or TNF. Among these compounds trovafloxacin (TVX) induced apoptosis in the liver and increased pro-inflammatory cytokines in mice exposed to LPS/TNF. The hepatocyte survival and the cytokine release after TNF/LPS stimulation relies on a pulsatile activation of NF-κB. We set out to evaluate the dynamic activation of NF-κB in response to TVX + TNF or LPS models, both in mouse and human cells. Remarkably, TVX prolonged the first translocation of NF-κB induced by TNF both in vivo and in vitro. The prolonged p65 translocation caused by TVX was associated with an increased phosphorylation of IKK and MAPKs and accumulation of inhibitors of NF-κB such as IκBα and A20 in HepG2. Coherently, TVX suppressed further TNF-induced NF-κB translocations in HepG2 leading to decreased transcription of ICAM-1 and inhibitors of apoptosis. TVX prolonged LPS-induced NF-κB translocation in RAW264.7 macrophages increasing the secretion of TNF. In summary, this study presents new, relevant insights into the mechanism of TVX-induced liver injury underlining the resemblance between mouse and human models. In this study we convincingly show that regularly used toxicity models provide a coherent view of relevant pathways for IDILI. We propose that assessment of the kinetics of activation of NF-κB and MAPKs is an appropriate tool for the identification of hepatotoxic compounds during drug development.
Assuntos
Antibacterianos/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/patologia , Fluoroquinolonas/toxicidade , Lipopolissacarídeos/farmacologia , Naftiridinas/toxicidade , Fator de Transcrição RelA/efeitos dos fármacos , Fator de Transcrição RelA/genética , Translocação Genética/efeitos dos fármacos , Fator de Necrose Tumoral alfa/farmacologia , Animais , Apoptose/efeitos dos fármacos , Doença Hepática Induzida por Substâncias e Drogas/genética , Citocinas/metabolismo , Humanos , Proteínas I-kappa B/metabolismo , Camundongos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Células RAW 264.7 , Fator de Necrose Tumoral alfa/metabolismoRESUMO
BACKGROUND: Adenosine receptors are involved in tumor growth, progression, and response to therapy. Among them, A2B receptor is highly expressed in various tumors. Furthermore, ionizing radiation induces translocation of epidermal growth factor receptor (EGFR), which promotes DNA repair and contributes to radioresistance. We hypothesized that A2B receptor might be involved in the translocation of EGFR. METHODS: We investigated whether A2B receptor is involved in EGFR translocation and DNA damage response (γH2AX/53BP1 focus formation) of lung cancer cells by means of immunofluorescence studies. Radiosensitivity was evaluated by colony formation assay after γ-irradiation. RESULTS: A2B receptor was expressed at higher levels in cancer cells than in normal cells. A2B receptor antagonist treatment or A2B receptor knockdown suppressed EGFR translocation, γH2AX/53BP1 focus formation, and colony formation of lung cancer cell lines A549, calu-6 and NCI-H446, compared with a normal cell line (beas-2b). γ-Irradiation-induced phosphorylation of src and EGFR was also attenuated by suppression of A2B receptor expression. CONCLUSION: Activation of A2B receptor mediates γ-radiation-induced translocation of EGFR and phosphorylation of src and EGFR, thereby promoting recovery of irradiated lung cancer cells from DNA damage. GENERAL SIGNIFICANCE: Our results indicate that A2B receptors contribute to radiation resistance in a cancer-cell-specific manner, and may be a promising target for radiosensitizers in cancer radiotherapy.
Assuntos
Neoplasias Pulmonares/radioterapia , Tolerância a Radiação/genética , Receptor A2B de Adenosina/genética , Células A549 , Dano ao DNA/efeitos da radiação , Reparo do DNA/efeitos da radiação , Receptores ErbB/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Histonas/genética , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Fosforilação/efeitos da radiação , Radiação , Radiossensibilizantes/farmacologia , Translocação Genética/efeitos dos fármacos , Translocação Genética/efeitos da radiação , Proteína 1 de Ligação à Proteína Supressora de Tumor p53/genética , Quinases da Família src/genéticaRESUMO
Gastrodin (GAS) is a component of Gastrodia elata Blume, with strong antioxidant activity in neurodegenerative diseases. Ferroptosis is similar to glutamate-induced cell death. This study was designed to explore the protective effects of GAS against glutamate-induced neurotoxicity in mice hippocampal neurons (HT-22) cells. HT-22 cells were cultured with glutamate in the presence or absence of GAS (1, 5, 25⯵M). Results showed that GAS inhibited glutamate-induced ferroptosis via Nrf2/HO-1 signaling pathway. Pretreatment of HT-22 cells with GAS significantly decreased glutamate-induced cell death and release of LDH. Ferrostatin-1, liproxstatin-1, and DFO treatments canceled these effect. GAS decreased glutamate-treatment ROS production in HT-22 cells. The concentration of iron ion was analyzed using ICP-MS. Metal analysis showed that GAS pretreatment normalized iron ion concentration in HT-22 cells. We found that GAS increased the nuclear translocation of Nrf2, up-regulated the downstream HO-1 protein expression in HT-22 cells following treatment with glutamate. Nrf2 knockdown greatly decreased glutamate-induced ferroptosis through HO-1. In conclusion, these results show that GAS protects HT-22 cells from the ferroptosis induced by glutamate through a new mechanism of Nrf2/HO-1 signaling pathway.
Assuntos
Álcoois Benzílicos/farmacologia , Ferroptose/efeitos dos fármacos , Glucosídeos/farmacologia , Ácido Glutâmico/toxicidade , Heme Oxigenase-1/efeitos dos fármacos , Proteínas de Membrana/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Transdução de Sinais/efeitos dos fármacos , Animais , Linhagem Celular , Gastrodia , L-Lactato Desidrogenase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Camundongos , Neurônios/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Translocação Genética/efeitos dos fármacosRESUMO
PURPOSE: Mantle Cell Lymphoma (MCL) is a B-cell neoplasm with CCND1 [t(11;14)(q13;q32), cyclin D1] translocation. The guidelines recommend various treatment options based on age, performance status and comorbidities. Our purpose was to analyze the clinical features and evaluate prognostic factors for survival of 78 MCL patients. METHODS: We retrospectively analyzed all MCL patients in two reference Hematology Departments between January 2001 and September 2018. RESULTS: The patient median age was 62 years (34-86) and 78.2% of them were male. The treatment regimens were RïCHOP in 42.3%, RïBendamustine in 26.9%, HyperCVAD in 9% and RïCHOP/RïDHAP alternating in 7.7%. Only 13 patients underwent autologous stem cell transplantation. Median overall survival (OS) was 77.8 months (53.8ï101.8) and median disease-free survival (DFS) was 20.6 months (14.2ï26.9), all patients included. Univariate analysis showed that MCL International Prognostic Index and neutrophil count effected OS in all groups (pï½0.047 and pï½0.001). Multivariate analysis showed that the neutrophil count at diagnosis was independent prognostic risk factor (HR=0.209, 95% confidence interval 0.069-0.629, pï½0.005) for OS. The median OS was 77.8 months in absolute neutrophil count (ANC) less than 7.5ï´103/µL and 14.8 months in ANC more than 7.5ï´103/µL (pï½0.001). CONCLUSIONS: Median OS is somewhat prolonged in the last years with new treatment approaches but MCL is still an incurable disease. The first choice of treatment in MCL patients was R-CHOP. Higher neutrophil count at the time of diagnosis has a detrimental effect on OS.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Linfócitos B/efeitos dos fármacos , Linfoma de Célula do Manto/tratamento farmacológico , Prognóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Linfócitos B/patologia , Cloridrato de Bendamustina/administração & dosagem , Terapia Combinada , Ciclofosfamida/administração & dosagem , Ciclofosfamida/efeitos adversos , Intervalo Livre de Doença , Doxorrubicina/administração & dosagem , Doxorrubicina/efeitos adversos , Feminino , Transplante de Células-Tronco Hematopoéticas , Humanos , Linfoma de Célula do Manto/genética , Linfoma de Célula do Manto/patologia , Masculino , Pessoa de Meia-Idade , Neutrófilos/efeitos dos fármacos , Prednisona/administração & dosagem , Prednisona/efeitos adversos , Fatores de Risco , Rituximab/administração & dosagem , Translocação Genética/efeitos dos fármacos , Vincristina/administração & dosagem , Vincristina/efeitos adversosRESUMO
OBJECTIVE: Understanding the clinical and genetic characteristics of pediatric acute lymphoblastic leukemia (ALL)
patients may help assigning the appropriate treatment. This study aims to understand patients' characteristics, "real-world"
treatment practice and outcomes of pediatric ALL. METHODS: A cohort of 213 pediatric ALL patients, treated at (King
Faisal Specialist Hospital and Research Center -Jeddah branch) KFSH and RC-J during the period of January 2002 to
December 2015 were analyzed retrospectively. Statistical analyses were performed on patients' demographic, clinical
and genetics characteristics and outcomes of different treatment protocols. Survival was evaluated using Kaplan-Meier
method, and differences in survival were tested using Log-Rank. Significance was set at 0.05 level. RESULTS: Median
age of the study cohort was 5 years (range 0.5-15 years) with 55.4% of male population. Majority of the patients had
pre-B-cell ALL (88.7%), WBC count <50, 000/µL at diagnosis (76.1%, median = 13.5/µL with a range of 0.51-553.0/
µL) with involvement of central nervous system (CNS) disease in 8.5%patients.Different common chromosomal
anomalies or abnormalities, including t(12, 21) translocation, MLL genre arrangements, trisomy (4, 10, 17)and others,
were detected. Early response to the risk-directed treatment received by the patients (91.1% achieving <5% blast in
the bone marrow) as well as the end of induction outcome (96.2%) was encouraging. CONCLUSION: We found that the
patients' clinical characteristics and distribution of genetic abnormalities were similar to those of the western countries.
Our findings show that the earlier gap between the western countries and KSA in terms of survival has been closed and
that competitive outcomes can be achieved with local infrastructure.
Assuntos
Antineoplásicos/uso terapêutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Adolescente , Medula Óssea/efeitos dos fármacos , Criança , Pré-Escolar , Aberrações Cromossômicas/efeitos dos fármacos , Feminino , Humanos , Lactente , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Estudos Retrospectivos , Arábia Saudita , Translocação Genética/efeitos dos fármacos , Translocação Genética/genéticaRESUMO
In a 2-year study the herbicide metazachlor (BAS 479H) was shown to significantly increase the incidence of liver tumours in female Wistar rats at a dietary level of 8000â¯ppm. As metazachlor is not a genotoxic agent, a series of in vivo and in vitro investigative studies were undertaken to elucidate the mode of action (MOA) for metazachlor-induced female rat liver tumour formation. Male and female Wistar rats were given diets containing 0 (control), 200 and 8000â¯ppm metazachlor for 3, 7, 14 and 28 days. The treatment of male rats with 200 and 8000â¯ppm metazachlor and female rats with 8000â¯ppm metazachlor resulted in significant increases in relative liver weight, which was associated with a centrilobular hepatocyte hypertrophy. Hepatocyte replicative DNA synthesis (RDS) was significantly increased in male rats given 8000â¯ppm metazachlor for 3 and 7 days and in female rats given 200â¯ppm metazachlor for 7-28 days and 8000â¯ppm metazachlor for 3-28 days. Significant increases in relative liver weight, centrilobular hepatocyte hypertrophy and hepatocyte RDS were also observed in male and female Wistar rats given and 500â¯ppm sodium phenobarbital (NaPB) for 3-28 days. The treatment of female Wistar rats with either 8000â¯ppm metazachlor for 7 days or with 500â¯ppm NaPB for 3 and 7 days resulted in the nuclear translocation of the hepatic constitutive androstane receptor (CAR). Treatment of male and female Wistar rats with 8000â¯ppm metazachlor for 14 days resulted in significant increases in hepatic microsomal total cytochrome P450 (CYP) content, CYP2B subfamily-dependent enzyme activities and mRNA levels, together with some increases in CYP3A enzyme activity and mRNA levels. The treatment of male Wistar rat hepatocytes with metazachlor (concentration range 0.5-50⯵M) and NaPB (500 µM) for 4 days resulted in increased CYP2B enzyme activities and mRNA levels; with metazachlor and NaPB also producing significant increases in hepatocyte RDS levels. Studies were also performed with hepatocytes from male Sprague-Dawley wild type (WT) rats and CAR knockout (CAR KO) rats. While both treatment with metazachlor and NaPB for 4 days increased CYP2B enzyme activities and mRNA levels in WT rat hepatocytes, only minor effects were observed in CAR KO rat hepatocytes. Treatment with both metazachlor and NaPB only increased RDS in WT but not in CAR KO rat hepatocytes. The treatment of hepatocytes from two male human donors with 0.5-25⯵M metazachlor or 500⯵M NaPB for 4 days resulted in increases in CYP2B6 and CYP3A4 mRNA levels but had no effect on hepatocyte RDS. EGF as concurrently used positive control demonstrated the expected RDS response in all rat and human hepatocyte cultures. In conclusion, a series of in vivo and in vitro investigative studies have demonstrated that metazachlor is a CAR activator in rat liver, with similar properties to the prototypical CAR activator phenobarbital. A robust MOA for metazachlor-induced female rat liver tumour formation has been established. Based on the lack of effect of metazachlor on RDS in human hepatocytes, it is considered that the MOA for metazachlor-induced rat liver tumour formation is qualitatively not plausible for humans.
Assuntos
Acetamidas/toxicidade , Herbicidas/toxicidade , Neoplasias Hepáticas Experimentais/induzido quimicamente , Animais , Células Cultivadas , Proteína de Membrana Semelhante a Receptor de Coxsackie e Adenovirus/efeitos dos fármacos , Proteína de Membrana Semelhante a Receptor de Coxsackie e Adenovirus/metabolismo , Replicação do DNA/efeitos dos fármacos , Feminino , Técnicas de Inativação de Genes , Hepatócitos/efeitos dos fármacos , Hepatócitos/patologia , Humanos , Fígado/patologia , Neoplasias Hepáticas Experimentais/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Tamanho do Órgão/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Ratos Wistar , Translocação Genética/efeitos dos fármacosRESUMO
INTRODUCTION: Human exposure to persistent organic pollutants (POPs) has been linked to genitourinary health-related conditions such as decreased sperm quality, hypospadias, and prostate cancer (PCa). Conventional risk assessment of POPs focuses on individual compounds. However, in real life, individuals are exposed to many compounds simultaneously. This might lead to combinatorial effects whereby the global effect of the mixture is different from the effect of the single elements or subgroups. POP mixtures may act as endocrine disruptors via the androgen receptor (AR) and potentially contribute to PCa development. AIM: To determine the endocrine disrupting activity of a POP mixture and sub-mixtures based upon exposure levels detected in a human Scandinavian population, on AR transactivation and translocation in vitro. MATERIALS AND METHODS: The Total POP mixture combined 29 chemicals modelled on the exposure profile of a Scandinavian population and 6 sub-mixtures: brominated (Br), chlorinated (Cl), Clâ¯+â¯Br, perfluorinated (PFAA), PFAA + Br, PFAA + Cl, ranging from 1/10× to 500× relative to what is found in human blood. Transactivation was measured by reporter gene assay (RGA) and translocation activity was measured by high content analysis (HCA), each using stably transfected AR model cell lines. RESULTS: No agonist activity in terms of transactivation and translocation was detected for any POP mixtures. In the presence of testosterone the Clâ¯+â¯Br mixture at 100× and 500× blood level antagonised AR transactivation, whereas the PFAA mixture at blood level increased AR transactivation (Pâ¯<â¯0.05). In the presence of testosterone the Cl and PFAA + Br mixtures at 1/10×, 1×, and 50× blood level antagonised AR translocation (Pâ¯<â¯0.05). CONCLUSION: Taken together, some combinations of POP mixtures can interfere with AR translocation. However, in the transactivation assay, these combinations did not affect gene transactivation. Other POP combinations were identified here as modulators of AR-induced gene transactivation without affecting AR translocation. Thus, to fully evaluate the effect of environmental toxins on AR signalling, both types of assays need to be applied.
Assuntos
Antagonistas de Receptores de Andrógenos/sangue , Disruptores Endócrinos/sangue , Poluentes Ambientais/sangue , Poluentes Ambientais/toxicidade , Receptores Androgênicos , Ativação Transcricional/efeitos dos fármacos , Antagonistas de Receptores de Andrógenos/toxicidade , Células Cultivadas , Disruptores Endócrinos/toxicidade , Genes Reporter , Humanos , Testosterona/farmacologia , Translocação Genética/efeitos dos fármacosRESUMO
Epidemiological studies of 1,3-butadiene (BD) exposures have reported a possible association with chronic myelogenous leukemia (CML), which is defined by the presence of the t(9;22) translocation (Philadelphia chromosome) creating an oncogenic BCR-ABL fusion gene. Butadiene diepoxide (DEB), the most mutagenic of three epoxides resulting from BD, forms DNA-DNA crosslink adducts that can lead to DNA double-strand breaks (DSBs). Thus, a study was designed to determine if (±)-DEB exposure of HL60â¯cells, a promyelocytic leukemia cell line lacking the Philadelphia chromosome, can produce t(9;22) translocations. In HL60â¯cells exposed for 3â¯h to 0-10⯵M DEB, overlapping dose-response curves suggested a direct relationship between 1,4-bis-(guan-7-yl)-2,3-butanediol crosslink adduct formation (Râ¯=â¯0.977, Pâ¯=â¯0.03) and cytotoxicity (Râ¯=â¯0.961, Pâ¯=â¯0.002). Experiments to define the relationships between cytotoxicity and the induction of micronuclei (MN), a dosimeter of DNA DSBs, showed that 24â¯h exposures of HL60â¯cells to 0-5.0⯵M DEB caused significant positive correlations between the concentration and (i) the degree of cytotoxicity (Râ¯=â¯0.998, pâ¯=â¯0.002) and (ii) the frequency of MN (Râ¯=â¯0.984, pâ¯=â¯0.016) at 48â¯h post exposure. To determine the relative induction of MN and t(9;22) translocations following exposures to DEB, or x-rays as a positive control for formation of t(9;22) translocations, HL60â¯cells were exposed for 24â¯h to 0, 1, 2.5, or 5⯵M DEB or to 0, 2.0, 3.5, or 5.0â¯Gy x-rays, or treatments demonstrated to yield 0, 20%, 50%, or 80% cytotoxicity. Treatments between 0 and 3.5â¯Gy x-rays caused significant dose-related increases in both MN (pâ¯<â¯0.001) and t(9;22) translocations (pâ¯=â¯0.01), whereas DEB exposures causing similar cytotoxicity levels did not increase translocations over background. These data indicate that, while DEB induces DNA DSBs required for formation of MN and translocations, acute DEB exposures of HL60â¯cells did not produce the Philadelphia chromosome obligatory for CML.