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1.
Anticancer Res ; 40(2): 1007-1014, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32014946

RESUMO

BACKGROUND/AIM: Myeloid cell leukemia-1 (MCL-1) is a member of the B-cell lymphoma-2 (Bcl-2) family of proteins, which regulate the intrinsic (mitochondrial) apoptotic cascade. MCL-1 inhibits apoptosis, which may be associated with resistance to cancer therapy. Therefore, in this study, the clinical role of MCL-1 in non-small cell lung cancer (NSCLC) was explored. PATIENTS AND METHODS: This retrospective study included 80 patients with stage 1-3A NSCLC, who underwent surgery without preoperative treatment between 2010 and 2011. MCL-1 expression and Ki-67 index were determined via immunohistochemical staining. Apoptotic index (AI) was determined via terminal deoxynucleotidyl transferase dUTP nick end labeling. RESULTS: The receiver operating characteristic curve analysis (area under curve=0.6785) revealed that MCL-1 expression in 30.0% of the NSCLC tumor cells was a significant cut-off for predicting prognosis. Tumors were considered MCL-1-positive if staining was observed in >30% of the cells. Thirty-six tumors (45.0%) were MCL-1-positive. However, there were no significant differences between MCL-1 expression and clinical variables. AI was lower in MCL-1-positive (2.2±3.6%) than in MCL-1-negative (5.2±7.9%) tumors, although the difference was not significant (p=0.1080). The Ki-67 index was significantly higher in MCL-1-positive than in MCL-1-negative tumors (18.0% vs. 3.0%; p<0.001). Five-year survival rate was significantly worse in patients with MCL-1-positive tumors (68.3%) than in those with MCL-1-negative tumors (93.1%, p=0.0057). Univariate [hazard ratio (HR)=5.041, p=0.0013], and multivariate analyses revealed that MCL-1 expression was a significant prognostic factor (HR=3.983, p=0.0411). CONCLUSION: MCL-1 expression in NSCLC cells correlated inversely with AI and positively with Ki-67 index. MCL-1 may serve as a potential prognostic biomarker and a novel therapeutic target in NSCLC.


Assuntos
Biomarcadores Tumorais , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Expressão Gênica , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/mortalidade , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Adulto , Idoso , Apoptose/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Feminino , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Prognóstico , Modelos de Riscos Proporcionais , Curva ROC
2.
Cancer Genomics Proteomics ; 16(5): 333-344, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31467227

RESUMO

BACKGROUND: Vitamin C has been used in combination with several target genes in the treatment of leukemia. Tet methylcytosine dioxygenase (Tet2), B-cell lymphoma 2 (Bcl2), and solute carrier family 23 member 2 (Slc23a2) are the major target genes in the treatment of leukemia and are relevant to vitamin C. MATERIALS AND METHODS: Using whole-genome expression profiles from mouse livers, the expression quantitative trait locus (eQTL), correlation matrix, and gene network graph were constructed with probes from each of these three genes and with their relative genes. The function of key genes was examined by their pathways and reported information. The results indicated that although direct correlations among their expression levels were not strong, alternative connecting pathways were discovered. By comparing the expression levels of one probe with known sequences from each of the three genes, we identified several key genes, induced myeloid leukemia cell differentiation protein (Mcl1), far upstream element-binding protein 1 (Fubp1), and tumor protein D52-like 2 (Tpd52l2), which play important roles in acute lymphocytic leukemia and acute myelocytic leukemia. In conclusion, Alternative pathways and key genes that connect Tet2, Bcl2, and Slc23a2 for their therapeutic applications with vitamin C were identified.


Assuntos
Ácido Ascórbico/farmacologia , Proteínas de Ligação a DNA/genética , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas/genética , Transportadores de Sódio Acoplados à Vitamina C/genética , Animais , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Fígado/fisiologia , Camundongos , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Locos de Características Quantitativas , Proteínas de Ligação a RNA/genética
3.
Mol Med Rep ; 20(2): 1561-1568, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31257502

RESUMO

Oxidative stress participates in several heart diseases and is an important mechanism contributing to the pathological alterations of myocardial cell injury. In recent years, ubiquitylation has been demonstrated to be an important biochemical reaction associated with apoptosis. To investigate the effects and interactions of the E3 ligase F­box and WD repeat domain containing 7 (Fbw7) and MCL1 apoptosis regulator, BCL2 family member (Mcl­1) in myocardial cells during oxidative stress, Cell Counting Kit­8, flow cytometry, western blot, reactive oxygen species and co­immunoprecipitation assays were conducted. The current study revealed that Fbw7 may facilitate apoptosis via the Mcl­1­Bax pathway in oxidative stress­induced myocardial H9c2 cell injury. Mcl­1 inhibits the functions of Bcl­2 family members, including the mitochondrial apoptosis factor Bax, to maintain cell viability; however, the present study suggested that Fbw7 may degrade Mcl­1 and impaired this process. Therefore, it may be hypothesized that Fbw­7 promotes myocardial cell injury via interacting with Mcl­1.


Assuntos
Apoptose/genética , Proteína 7 com Repetições F-Box-WD/genética , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Miócitos Cardíacos/metabolismo , Proteína X Associada a bcl-2/genética , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Proteína 7 com Repetições F-Box-WD/antagonistas & inibidores , Proteína 7 com Repetições F-Box-WD/metabolismo , Regulação da Expressão Gênica , Peróxido de Hidrogênio/farmacologia , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Miócitos Cardíacos/citologia , Miócitos Cardíacos/efeitos dos fármacos , Estresse Oxidativo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Ratos , Transdução de Sinais , Proteína X Associada a bcl-2/metabolismo
4.
Elife ; 82019 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-31294695

RESUMO

Overexpression of anti-apoptotic proteins MCL1 and Bcl-xL are frequently observed in many cancers. Inhibitors targeting MCL1 are in clinical development, however numerous cancer models are intrinsically resistant to this approach. To discover mechanisms underlying resistance to MCL1 inhibition, we performed multiple flow-cytometry based genome-wide CRISPR screens interrogating two drugs that directly (MCL1i) or indirectly (CDK9i) target MCL1. Remarkably, both screens identified three components (CUL5, RNF7 and UBE2F) of a cullin-RING ubiquitin ligase complex (CRL5) that resensitized cells to MCL1 inhibition. We find that levels of the BH3-only pro-apoptotic proteins Bim and Noxa are proteasomally regulated by the CRL5 complex. Accumulation of Noxa caused by depletion of CRL5 components was responsible for re-sensitization to CDK9 inhibitor, but not MCL1 inhibitor. Discovery of a novel role of CRL5 in apoptosis and resistance to multiple types of anticancer agents suggests the potential to improve combination treatments.


Assuntos
Proteínas Culina/genética , Quinase 9 Dependente de Ciclina/genética , Neoplasias Pulmonares/tratamento farmacológico , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Proteína 11 Semelhante a Bcl-2/genética , Linhagem Celular Tumoral , Quinase 9 Dependente de Ciclina/antagonistas & inibidores , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Proteína de Sequência 1 de Leucemia de Células Mieloides/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-bcl-2/genética , Complexos Ubiquitina-Proteína Ligase/genética , Ubiquitina-Proteína Ligases/genética
5.
BMC Cancer ; 19(1): 739, 2019 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-31351462

RESUMO

BACKGROUND: Genipin is a compound derived from gardenia fruit extract. Although Genipin has anti-tumor effects in various cancers, its effect and mechanism in gastric cancer remain unclear. Here, we investigated the relationship between the anticancer effect of Genipin and signal transducer and activator of transcription (Stat3)/myeloid cell leukemia-1 (Mcl-1) in human gastric cancers. METHODS: MTT assays were performed to determine the cell viability of gastric cancer and gastric epithelial cell lines (AGS, MKN45, SNU638, MKN74, HFE-145). A TUNEL assay and Western blotting were carried out to investigate apoptosis. Stat3 activity was measured by proteome profiler phospho kinase array, immunofluorescence and immunoblotting. Mitochondria function was monitored with an XF24 analyzer and by flow cytometry, confocal microscopy using fluorescent probes for general mitochondrial membrane potential (MMP). RESULTS: Genipin induced apoptosis in gastric cancer cells, including AGS and MKN45 cells. Genipin also reduced Mcl-1 mRNA and protein levels. Furthermore, we found that phosphorylation of Stat3 is regulated by Genipin. Additionally, the protein level of phospho Janus kinase 2 (JAK2) was decreased by Genipin treatment, indicating that the Stat3/JAK2/Mcl-1 pathway is suppressed by Genipin treatment in gastric cancer cells. Mcl-1 is closely related to mitochondrial function. These findings suggest that Genipin contributes to the collapse of mitochondrial functions like MMP. CONCLUSIONS: Genipin induced apoptosis by suppressing the Stat3/Mcl-1 pathway and led to mitochondrial dysfunction. Our results reveal a novel mechanism for the anti-cancer effect of Genipin in gastric cancer.


Assuntos
Apoptose/efeitos dos fármacos , Regulação para Baixo , Iridoides/farmacologia , Mitocôndrias/metabolismo , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Fator de Transcrição STAT3/metabolismo , Neoplasias Gástricas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Humanos , Janus Quinase 2/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Fosforilação/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Neoplasias Gástricas/patologia , Transfecção
6.
Medicine (Baltimore) ; 98(28): e16245, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31305404

RESUMO

RATIONALE: Primary splenic angiosarcoma (PSA) is a rare mesenchymal malignancy of the splenic vascular origin often with a dismal prognosis. Genomic profile may provide evidence for the solution of therapy. PATIENT CONCERNS: We reported a case of a 51-year-old woman with splenectomy 4 years ago and the postoperative histopathology diagnosis revealed "splenic hemangioma" with spontaneous rupture. Two years after the operation, the patient's rechecked abdominal computed tomography (CT) showed multiple hepatic occupations. DIAGNOSES: Pathological test suggested PSA hepatic metastasis. INTERVENTIONS: The patient was treated with trans-catheter arterial chemoembolization (TACE) and a pathological diagnosis of PSA was highly suspected in the hepatic biopsy. Four somatic alterations, phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA), Fos proto-oncogene, AP-1 transcription factor subunit (FOS), MCL1 apoptosis regulator (MCL1), and phosphoinositide-3-kinase regulatory subunit 1 (PIK3R1) were detected in the tumor tissue using a Next generation sequencing (NGS) technology. The results prompted that the patient may get clinical benefit from using some agents for targeted therapy, Everolimus, Temsirolimus, or Copanlisib. OUTCOMES: The patient refused targeted therapy. As a result, the patient passed away within 51 months after splenectomy. LESSONS: PSA is an aggressive disease that often presented with a high propensity for metastasis and rupture hemorrhage. Some of these mutations were first discovered in PSA and these findings added new contents to the genomic mutation profile of PSA.


Assuntos
Hemangiossarcoma/cirurgia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/secundário , Esplenectomia , Neoplasias Esplênicas/cirurgia , Classe I de Fosfatidilinositol 3-Quinases/genética , Evolução Fatal , Feminino , Hemangiossarcoma/genética , Hemangiossarcoma/patologia , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/terapia , Pessoa de Meia-Idade , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas c-fos/genética , Neoplasias Esplênicas/genética , Neoplasias Esplênicas/patologia
7.
PLoS One ; 14(5): e0217657, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31150457

RESUMO

Lung cancer is among the common and deadly cancers. Although the treatment options for late-stage cancer patients have continued to increase in numbers, the overall survival rates for these patients have not shown significant improvement. This highlights the need for new targets and drugs to more effectively treat lung cancer patients. In this study, we characterize the MCL-1 inhibitor maritoclax alone or in combination with a BCL-2/xL inhibitor in a panel of lung cancer cell lines. BCL-2 family proteins, phosphorylated proteins, and apoptosis were monitored following the treatments. We found that maritoclax was effective at inhibiting growth in these lung cancer cells. We also establish that cell lines with EGFR mutations were most sensitive to the combined inhibition of MCL-1 and BCL-2/xL. In addition, a high level of phosphorylated AKT (S473) was identified as a marker for sensitivity to the combination treatment. This work has defined EGFR mutations and AKT phosphorylation as markers for sensitivity to combined MCL-1 and BCL-2/xL targeted therapy and establishes a rationale to explore multiple BCL-2 family members in patients who are refractory to EGFR inhibitor treatment. Our data support the design of a clinical trial that aims to employ inhibitors of the BCL-2 family of proteins in lung cancer patients.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Proteínas Proto-Oncogênicas c-bcl-2/genética , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/genética , Citometria de Fluxo , Humanos , Mutação/genética , Proteína de Sequência 1 de Leucemia de Células Mieloides/antagonistas & inibidores , Proteína Oncogênica v-akt/genética , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Pirróis/farmacologia , Proteína bcl-X/antagonistas & inibidores , Proteína bcl-X/genética
8.
Artif Cells Nanomed Biotechnol ; 47(1): 1384-1395, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31174432

RESUMO

lncRNA ANRIL was reported to be closely related to ischaemic stroke (IS). In this study, we used oxygen-glucose deprivation (OGD) to stimulate rat adrenal medulla-derived pheochromocytoma cell line PC-12 to construct an in vitro IS cell model and investigated the role of ANRIL and the underlying mechanism. PC-12 cells were stimulated by OGD and/or transfected with pc-ANRIL, si-ANRIL, miR-127 mimic, miR-127 inhibitor, pEX-Mcl-1, sh-Mcl-1 and their negative controls. Cell viability, apoptosis, mRNA and protein expression was detected using CCK-8 assay, flow cytometry assay, qRT-PCR and western blot, respectively. Results showed that OGD-induced PC-12 cell injury and decreased ANRIL expression. ANRIL overexpression significantly reduced OGD-induced PC-12 cell injury evidenced by increasing cell viability and decreasing apoptosis, while ANRIL silence led to the opposite results. Meanwhile, dysregulation of ANRIL altered the expression of apoptotic proteins. Furthermore, ANRIL negatively regulated miR-127 expression. miR-127 overexpression significantly enhanced OGD-induced PC-12 cell injury. In addition, Mcl-1 expression was negatively regulated by miR-127, besides ANRIL up-regulated Mcl-1 expression by down-regulation of miR-127. Mcl-1 overexpression alleviated cell injury and miR-127 silence up-regulated Mcl-1 expression. In conclusion, lncRNA ANRIL alleviated OGD-induced PC-12 cell injury as evidenced. PI3K/AKT pathway might be involved in this regulating progression.


Assuntos
Isquemia Encefálica/complicações , Glucose/metabolismo , Oxigênio/metabolismo , RNA Longo não Codificante/genética , Acidente Vascular Cerebral/genética , Acidente Vascular Cerebral/metabolismo , Animais , Regulação para Baixo/genética , MicroRNAs/genética , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Células PC12 , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Transdução de Sinais/genética , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/patologia
9.
Daru ; 27(1): 1-7, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31077090

RESUMO

BACKGROUND: Anaplastic thyroid carcinoma (ATC) is the most lethal malignancy in thyroid carcinomas. Long non-coding RNAs (lncRNAs) are a member of non-coding RNAs, regulating the expression of gene. Metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) is an onco-lncRNA that is overexpressed in several carcinomas including ATC. Evidence showed that MALAT1 has a crucial function in apoptosis, and cell cycle progression. OBJECTIVES: In order to take advantage of 3D cell culture system in cancer investigation, we have used a 3D in vitro ATC model to determine the effect of dual MEK/Aurora kinase inhibitor BI-847325 anticancer drug on the fundamental molecular mechanisms of MALAT1-mediated gene regulation in ATC. METHODS: In this study, ATC cell lines (C643 and SW1736) were grown in alginate scaffold. Encapsulated cells were treated by BI-847325. Changes in expression of MALAT1, Mcl1, miR-363-3p, and cyclinD1 were measured by qRT-PCR. RESULTS AND CONCLUSION: MALAT1 gene expression following BI-847325 treatment was significantly downregulated in C643 and SW1736 cell lines. Reversely, miR-363-3p expression was significantly upregulated by BI-847325 in both ATC cell lines. Mcl1 expression was significantly downregulated after treatment in C643 cell lines. Moreover, the expression of this gene was not significantly reduced following BI-847325 treatment in SW1736 cell line. Additionally, cyclin D1 expression was significantly downregulated after treatment in both ATC cell lines. Altogether, the result of this study was the first report of MALAT1's molecular function in ATC and suggested that BI-847325 which inhibits both MEK and Aurora kinase family could be effective against ATC by regulating the genes involved in cell cycle and apoptosis including MALAT1and its downstream genes. Graphical abstract Schematic representation of the biological role of MALAT1 in cyclin D1, miR-363-3p and Mcl1 gene regulations. Stimulation of receptor tyrosine kinase (RTK) by growth factors (GFs) phosphorylates RAS that subsequently activates RAF. Then, RAF phosphorylates MEK. Consequently, activated MEK phosphorylates ERK downstream effector, leading to the MALAT1 gene expression. MALAT1 is a negative regulator of Mcl1 mRNA by sponging of miR-363-3p. In addition, MALAT1 leads to Axin1 and APC downregulation and Wnt/ß-catenin signaling pathway activation. Stable ß-catenin translocates from the cytoplasm to the nucleus and promotes cyclin D1 gene expression.


Assuntos
Compostos de Anilina/farmacologia , Técnicas de Cultura de Células/métodos , Indóis/farmacologia , RNA Longo não Codificante/genética , Carcinoma Anaplásico da Tireoide/genética , Neoplasias da Glândula Tireoide/genética , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ciclina D1/genética , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , MicroRNAs/genética , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética
10.
J Agric Food Chem ; 67(18): 5159-5168, 2019 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-31006247

RESUMO

In the current study, nine amide alkaloids, including two new dimeric amides and a new natural product, were identified from Piper nigrum. Among them, seven compounds sensitized paclitaxel-resistant cervical cancer cells HeLa/PTX to paclitaxel. Piperine was a major component obtained from Piper nigrum, and its sensitization mechanism was investigated. Combination treatment enhanced cell apoptosis, which was mediated by downregulation of phospho-Akt and Mcl-1. Piperine (50 µM) combined with paclitaxel (200 nM) downregulated Mcl-1 protein expression with a decrease of 35.9 ± 9.5% ( P < 0.05). Moreover, overexpression of Mcl-1 attenuated the inhibitory effect of this combination. Furthermore, combination treatments of six dimeric amide alkaloids and paclitaxel all downregulated Mcl-1 protein expression with a decrease ranging from 23.5 ± 9.7% to 41.7 ± 7.2% ( P < 0.05). We reveal, for the first time, that dimeric amide alkaloids from plants possess a remarkable sensitization effect on cancer cells to paclitaxel.


Assuntos
Alcaloides/farmacologia , Antineoplásicos/farmacologia , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Paclitaxel/farmacologia , Piper nigrum/química , Extratos Vegetais/farmacologia , Neoplasias do Colo do Útero/genética , Alcaloides/química , Alcaloides/isolamento & purificação , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Sinergismo Farmacológico , Feminino , Células HeLa , Humanos , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/fisiopatologia
11.
BMC Cancer ; 19(1): 243, 2019 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-30885150

RESUMO

BACKGROUND: High-risk neuroblastoma with N-Myc amplification remains a therapeutic challenge in paediatric oncology. Antagonism of pro-death Bcl-2 homology (BH) proteins to pro-survival BH members such as Mcl-1 and Bcl-2 has become a treatment approach, but previous studies suggest that a combined inhibition of Bcl-2 and Mcl-1 is necessary. TW-37 inhibits Mcl-1 and Bcl-2 with almost the same affinity. However, single-agent cytotoxicity of TW-37 in neuroblastoma cell lines has not been investigated. METHODS: Cell viability, apoptosis, proliferation and changes in growth properties were determined in SKNAS, IMR-5, SY5Y and Kelly cells after treatment with TW-37. After transfection with Mcl-1 or Bcl-2 siRNA, apoptosis and proliferation were investigated in Kelly cells. Mice with Kelly cell line xenografts were treated with TW-37 and tumor growth, survival and apoptosis were determined. RESULTS: Cell lines with N-Myc amplification were more sensitive to TW-37 treatment, IC50 values for IMR-5 and Kelly cells being 0.28 µM and 0.22 µM, compared to SY5Y cells and SKNAS cells (IC50 0.96 µM and 0.83 µM). Treatment with TW-37 resulted in increased apoptosis and reduced proliferation rates, especially in IMR5 and Kelly cells. Bcl-2 as well as Mcl-1 knockdown induced apoptosis in Kelly cells. TW-37 led to a decrease in tumor growth and a favorable survival (p = 0.0379) in a Kelly neuroblastoma xenografts mouse model. CONCLUSION: TW-37 has strong single-agent cytotoxicity in vitro and in vivo. Therefore, combined inhibition of Bcl-2/Mcl-1 by TW-37 in N-Myc amplified neuroblastoma may represent an interesting therapeutic strategy.


Assuntos
Benzamidas/farmacologia , Proteína de Sequência 1 de Leucemia de Células Mieloides/antagonistas & inibidores , Neuroblastoma/tratamento farmacológico , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Sulfonas/farmacologia , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Benzamidas/uso terapêutico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Amplificação de Genes , Técnicas de Silenciamento de Genes , Humanos , Concentração Inibidora 50 , Camundongos , Camundongos Nus , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Proteína Proto-Oncogênica N-Myc/genética , Neuroblastoma/genética , Neuroblastoma/patologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Sulfonas/uso terapêutico , Resultado do Tratamento , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Cell Oncol (Dordr) ; 42(3): 287-301, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30859392

RESUMO

PURPOSE: Anti-apoptotic and pro-migratory phenotypes are hallmarks of neoplastic diseases, including primary brain malignancies. In this work, we examined whether reprogramming of the apoptotic and migratory machineries through a multi-targeting approach would induce enhanced cell death and enhanced inhibition of the migratory capacity of glioblastoma cells. METHODS: Preclinical testing and molecular analyses of combined inhibition of Bcl-2/Bcl-xL and RAC1 were performed in established, primary cultured and stem-like glioblastoma cell systems. RESULTS: We found that the combined inhibition of Bcl-2/Bcl-xL and RAC1 resulted in synergistic pro-apoptotic and anti-migratory effects in a broad range of different glioblastoma cells. At the molecular level, we found that RAC1 inhibition led to a decreased expression of the deubiquitinase Usp9X, followed by a decreased stability of Mcl-1. We also found that the combined inhibition led to a significantly decreased migratory activity and that tumor formation of glioblastoma cells on chorion allantoic membranes of chicken embryos was markedly impaired following the combined inhibition. CONCLUSIONS: Our data indicate that concomitant inhibition of RAC1 and Bcl-2/Bcl-xL induces pro-apoptotic and anti-migratory glioblastoma phenotypes as well as synergistic anti-neoplastic activities. The clinical efficacy of this inhibitory therapeutic strategy warrants further evaluation.


Assuntos
Compostos de Anilina/farmacologia , Proteínas Reguladoras de Apoptose/antagonistas & inibidores , Apoptose/efeitos dos fármacos , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Sulfonamidas/farmacologia , Ubiquitina Tiolesterase/metabolismo , Proteínas rac1 de Ligação ao GTP/antagonistas & inibidores , Antineoplásicos/farmacologia , Apoptose/genética , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Movimento Celular/genética , Regulação para Baixo/efeitos dos fármacos , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Interferência de RNA , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Ubiquitina Tiolesterase/genética , Proteína bcl-X/antagonistas & inibidores , Proteína bcl-X/genética , Proteína bcl-X/metabolismo , Proteínas rac1 de Ligação ao GTP/genética , Proteínas rac1 de Ligação ao GTP/metabolismo
13.
Proc Natl Acad Sci U S A ; 116(8): 2961-2966, 2019 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-30718431

RESUMO

Chemoresistance is a severe outcome among patients with ovarian cancer that leads to a poor prognosis. MCL1 is an antiapoptotic member of the BCL-2 family that has been found to play an essential role in advancing chemoresistance and could be a promising target for the treatment of ovarian cancer. Here, we found that deubiquitinating enzyme 3 (DUB3) interacts with and deubiquitinates MCL1 in the cytoplasm of ovarian cancer cells, which protects MCL1 from degradation. Furthermore, we identified that O6-methylguanine-DNA methyltransferase (MGMT) is a key activator of DUB3 transcription, and that the MGMT inhibitor PaTrin-2 effectively suppresses ovarian cancer cells with elevated MGMT-DUB3-MCL1 expression both in vitro and in vivo. Most interestingly, we found that histone deacetylase inhibitors (HDACis) could significantly activate MGMT/DUB3 expression; the combined administration of HDACis and PaTrin-2 led to the ideal therapeutic effect. Altogether, our results revealed the essential role of the MGMT-DUB3-MCL1 axis in the chemoresistance of ovarian cancer and identified that a combined treatment with HDACis and PaTrin-2 is an effective method for overcoming chemoresistance in ovarian cancer.


Assuntos
Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Endopeptidases/genética , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Neoplasias Ovarianas/tratamento farmacológico , Proteínas Supressoras de Tumor/genética , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Inibidores de Histona Desacetilases/farmacologia , Humanos , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Transdução de Sinais/efeitos dos fármacos
14.
In Vitro Cell Dev Biol Anim ; 55(3): 159-168, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30737632

RESUMO

Parthenogenetically developed embryos are efficient sources of in vitro embryo production, having less ethical issue and being useful for investigating culture conditions/treatments, early developmental, genomic studies, and homonymous source of stem cells. Keeping its advantages in mind, we aimed to study the effects of different activating agents on embryo production and its quality and gene expression. In the present study, 1348 immature oocytes recovered were parthenogenetically developed to embryos. Usable-quality immature oocytes were collected by puncturing the surface follicles and matured in in vitro maturation (IVM) medium for 27 h in a humidified 5% CO2 incubator at 38.5°C. The matured oocytes were parthenogenetically activated by exposure to 5 µM calcium ionophore for 5 min or 7% ethanol for 7 min sequentially followed by 4 h incubation in 2 mM 6-DMAP and then in vitro cultured (IVC) in RVCL/G-2 medium for 8 days. Matured oocytes were activated by calcium ionophore, the cleavage rate observed was 76.67 ± 3.47%, and further they developed into 4-cell, 8-16-cell, morula, blastocyst, and hatched blastocyst with 85.30 ± 1.57%, 70.60 ± 2.00%, 45.05 ± 2.66%, 22.89 ± 2.40%, and 5.70 ± 1.97%, respectively. Whereas ethanol-activated oocytes showed cleavage rate of 87.60 ± 1.70% and further culture developed into 4-cell, 8-16 cell, morula, blastocyst, and hatched blastocyst with 86.14 ± 1.03%, 71.56 ± 2.21%, 40.90 ± 2.45%, 19.02 ± 1.26%, and 2.22 ± 0.38%, respectively. Blastocyst developed from calcium ionophore-activated oocytes showed significantly (P < 0.05) higher total cell number (282.25 ± 27.02 vs 206.00 ± 40.46) and a lower apoptotic index (2.42 ± 0.46 vs 4.07 ± 1.44) than blastocyst developed from ethanol-activated oocytes. The relative expression of anti-apoptotic genes (BCL2, BCL2A1, MCL) at different stages of embryos produced by either calcium ionophore or ethanol activation was found to be increased in earlier stages and decreased in later stages of embryonic development. Similarly, when these embryos were subjected to pro-apoptotic genes (BAX, BAD, BAK), expression was found to be slightly higher in blastocysts than other stages. This study shows that calcium ionophore-activated blastocysts were developmentally more competent than the ethanol-activated blastocysts.


Assuntos
Blastocisto/efeitos dos fármacos , Ionóforos de Cálcio/farmacologia , Cabras/embriologia , Técnicas de Maturação in Vitro de Oócitos/métodos , Partenogênese/efeitos dos fármacos , Adenina/análogos & derivados , Adenina/farmacologia , Animais , Apoptose/genética , Blastocisto/citologia , Etanol/farmacologia , Feminino , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Genes bcl-2 , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Oócitos/efeitos dos fármacos , Oócitos/fisiologia , Partenogênese/fisiologia , Proteína X Associada a bcl-2/genética
15.
J Biol Chem ; 294(15): 5945-5955, 2019 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-30782845

RESUMO

GADD34 (growth arrest and DNA damage-inducible gene 34) plays a critical role in responses to DNA damage and endoplasmic reticulum stress. GADD34 has opposing effects on different stimuli-induced cell apoptosis events, but the reason for this is unclear. Here, using immunoblotting analyses and various molecular genetic approaches in HepG2 and SMMC-7721 cells, we demonstrate that GADD34 protects hepatocellular carcinoma (HCC) cells from tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-induced apoptosis by stabilizing a BCL-2 family member, myeloid cell leukemia 1 (MCL-1). We found that GADD34 knockdown decreased MCL-1 levels and that GADD34 overexpression up-regulated MCL-1 expression in HCC cells. GADD34 did not affect MCL-1 transcription but enhanced MCL-1 protein stability. The proteasome inhibitor MG132 abrogated GADD34 depletion-induced MCL-1 down-regulation, suggesting that GADD34 inhibits the proteasomal degradation of MCL-1. Furthermore, GADD34 overexpression promoted extracellular signal-regulated kinase (ERK) phosphorylation through a signaling axis that consists of the E3 ubiquitin ligase tumor necrosis factor receptor-associated factor 6 (TRAF6) and transforming growth factor-ß-activated kinase 1 (MAP3K7)-binding protein 1 (TAB1), which mediated the up-regulation of MCL-1 by GADD34. Of note, TRAIL up-regulated both GADD34 and MCL-1 levels, and knockdown of GADD34 and TRAF6 suppressed the induction of MCL-1 by TRAIL. Correspondingly, GADD34 knockdown potentiated TRAIL-induced apoptosis, and MCL-1 overexpression rescued TRAIL-treated and GADD34-depleted HCC cells from cell death. Taken together, these findings suggest that GADD34 inhibits TRAIL-induced HCC cell apoptosis through TRAF6- and ERK-mediated stabilization of MCL-1.


Assuntos
Apoptose , Carcinoma Hepatocelular/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Neoplasias Hepáticas/metabolismo , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Proteínas de Neoplasias/metabolismo , Proteína Fosfatase 1/metabolismo , Fator 6 Associado a Receptor de TNF/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , MAP Quinases Reguladas por Sinal Extracelular/genética , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Proteínas de Neoplasias/genética , Proteína Fosfatase 1/genética , Estabilidade Proteica , Fator 6 Associado a Receptor de TNF/genética , Ligante Indutor de Apoptose Relacionado a TNF/genética
16.
Structure ; 27(4): 606-617.e5, 2019 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-30773399

RESUMO

Understanding the relationship between protein sequence and structure well enough to design new proteins with desired functions is a longstanding goal in protein science. Here, we show that recurring tertiary structural motifs (TERMs) in the PDB provide rich information for protein-peptide interaction prediction and design. TERM statistics can be used to predict peptide binding energies for Bcl-2 family proteins as accurately as widely used structure-based tools. Furthermore, design using TERM energies (dTERMen) rapidly and reliably generates high-affinity peptide binders of anti-apoptotic proteins Bfl-1 and Mcl-1 with just 15%-38% sequence identity to any known native Bcl-2 family protein ligand. High-resolution structures of four designed peptides bound to their targets provide opportunities to analyze the strengths and limitations of the computational design method. Our results support dTERMen as a powerful approach that can complement existing tools for protein engineering.


Assuntos
Antígenos de Histocompatibilidade Menor/química , Proteína de Sequência 1 de Leucemia de Células Mieloides/química , Peptídeos/química , Proteínas Proto-Oncogênicas c-bcl-2/química , Sequência de Aminoácidos , Sítios de Ligação , Clonagem Molecular , Cristalografia por Raios X , Expressão Gênica , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Humanos , Antígenos de Histocompatibilidade Menor/genética , Antígenos de Histocompatibilidade Menor/metabolismo , Simulação de Acoplamento Molecular , Proteína de Sequência 1 de Leucemia de Células Mieloides/antagonistas & inibidores , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Peptídeos/genética , Peptídeos/metabolismo , Ligação Proteica , Conformação Proteica em alfa-Hélice , Engenharia de Proteínas , Domínios e Motivos de Interação entre Proteínas , Estrutura Terciária de Proteína , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Alinhamento de Sequência , Relação Estrutura-Atividade , Termodinâmica
17.
Leukemia ; 33(7): 1663-1674, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30700841

RESUMO

The viability of chronic lymphocytic leukemia (CLL) is critically dependent upon staving off death by apoptosis, a hallmark of CLL pathophysiology. The recognition that Mcl-1, a major component of the anti-apoptotic response, is intrinsically short-lived and must be continually resynthesized suggested a novel therapeutic approach. Pateamine A (PatA), a macrolide marine natural product, inhibits cap-dependent translation by binding to the initiation factor eIF4A. In this study, we demonstrated that a synthetic derivative of PatA, des-methyl des-amino PatA (DMDAPatA), blocked mRNA translation, reduced Mcl-1 protein and initiated apoptosis in CLL cells. This action was synergistic with the Bcl-2 antagonist ABT-199. However, avid binding to human plasma proteins limited DMDAPatA potency, precluding further development. To address this, we synthesized a new series of PatA analogs and identified three new leads with potent inhibition of translation. They exhibited less plasma protein binding and increased cytotoxic potency toward CLL cells than DMDAPatA, with greater selectivity towards CLL cells over normal lymphocytes. Computer modeling analysis correlated their structure-activity relationships and suggested that these compounds may act by stabilizing the closed conformation of eIF4A. Thus, these novel PatA analogs hold promise for application to cancers within the appropriate biological context, such as CLL.


Assuntos
Apoptose/efeitos dos fármacos , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Compostos de Epóxi/farmacologia , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Macrolídeos/farmacologia , Proteína de Sequência 1 de Leucemia de Células Mieloides/antagonistas & inibidores , Biossíntese de Proteínas/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Sulfonamidas/farmacologia , Tiazóis/farmacologia , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Sinergismo Farmacológico , Quimioterapia Combinada , Fator de Iniciação 4A em Eucariotos/química , Feminino , Seguimentos , Regulação Neoplásica da Expressão Gênica , Humanos , Leucemia Linfocítica Crônica de Células B/metabolismo , Leucemia Linfocítica Crônica de Células B/patologia , Masculino , Pessoa de Meia-Idade , Modelos Moleculares , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Prognóstico , Conformação Proteica , RNA Mensageiro/antagonistas & inibidores , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Células Tumorais Cultivadas
18.
Int J Biol Sci ; 15(3): 579-586, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30745844

RESUMO

Daunorubicin (Dnr) is at the forefront of acute myeloid leukemia (AML) therapy, but drug resistance poses a major threat to treatment success. MicroRNA (miR)-9 has been shown to have a pivotal role in AML development. However, little is known about the role of miR-9 in Dnr resistance in AML. We explored the potential role of miR-9 in Dnr resistance in AML cells and its mechanism of action. AML cell lines with high half-maximal inhibitory concentration to Dnr in vivo had significantly low miR-9 expression. miR-9 overexpresssion sensitized AML cells to Dnr, inhibited cell proliferation, and enhanced the ability of Dnr to induce apoptosis; miR-9 knockdown had the opposite effects. Mechanistic studies demonstrated that eukaryotic translation initiation factor 5A-2 (EIF5A2) was a putative target of miR-9, which was inversely correlated with the expression and role of miR-9 in AML cells. miR-9 improved the anti-tumor effects of Dnr by inhibiting myeloid cell leukemia-1 (MCL-1) expression, which was dependent on downregulation of EIF5A2 expression. These results suggest that miR-9 has an essential role in Dnr resistance in AML cells through inhibition of the EIF5A2/MCL-1 axis in AML cells. Our data highlight the potential application of miR-9 in chemotherapy for AML patients.


Assuntos
Leucemia Mieloide Aguda/metabolismo , MicroRNAs/metabolismo , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Fatores de Iniciação de Peptídeos/metabolismo , Proteínas de Ligação a RNA/metabolismo , Apoptose/efeitos dos fármacos , Apoptose/genética , Western Blotting , Linhagem Celular Tumoral , Proliferação de Células/genética , Proliferação de Células/fisiologia , Células HL-60 , Humanos , Leucemia Mieloide Aguda/genética , MicroRNAs/genética , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Fatores de Iniciação de Peptídeos/genética , Proteínas de Ligação a RNA/genética , Reação em Cadeia da Polimerase em Tempo Real
19.
Nat Commun ; 10(1): 137, 2019 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-30635584

RESUMO

Dysregulation of RNA splicing by spliceosome mutations or in cancer genes is increasingly recognized as a hallmark of cancer. Small molecule splicing modulators have been introduced into clinical trials to treat solid tumors or leukemia bearing recurrent spliceosome mutations. Nevertheless, further investigation of the molecular mechanisms that may enlighten therapeutic strategies for splicing modulators is highly desired. Here, using unbiased functional approaches, we report that the sensitivity to splicing modulation of the anti-apoptotic BCL2 family genes is a key mechanism underlying preferential cytotoxicity induced by the SF3b-targeting splicing modulator E7107. While BCL2A1, BCL2L2 and MCL1 are prone to splicing perturbation, BCL2L1 exhibits resistance to E7107-induced splicing modulation. Consequently, E7107 selectively induces apoptosis in BCL2A1-dependent melanoma cells and MCL1-dependent NSCLC cells. Furthermore, combination of BCLxL (BCL2L1-encoded) inhibitors and E7107 remarkably enhances cytotoxicity in cancer cells. These findings inform mechanism-based approaches to the future clinical development of splicing modulators in cancer treatment.


Assuntos
Proteínas Reguladoras de Apoptose/genética , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Melanoma/tratamento farmacológico , Antígenos de Histocompatibilidade Menor/genética , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Proteínas Proto-Oncogênicas c-bcl-2/genética , Processamento de RNA/efeitos dos fármacos , Proteína bcl-X/genética , Células A549 , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/genética , Linhagem Celular Tumoral , Doxiciclina/farmacologia , Sinergismo Farmacológico , Compostos de Epóxi/farmacologia , Feminino , Humanos , Neoplasias Pulmonares/genética , Macrolídeos/farmacologia , Melanoma/genética , Camundongos , Camundongos Nus , Interferência de RNA , Processamento de RNA/genética , RNA Interferente Pequeno/genética , Spliceossomos/efeitos dos fármacos , Spliceossomos/genética , Sequenciamento Completo do Exoma , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Am J Respir Crit Care Med ; 200(1): 84-97, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-30649895

RESUMO

Rationale: Antimicrobial resistance challenges therapy of pneumonia. Enhancing macrophage microbicidal responses would combat this problem but is limited by our understanding of how alveolar macrophages (AMs) kill bacteria. Objectives: To define the role and mechanism of AM apoptosis-associated bacterial killing in the lung. Methods: We generated a unique CD68.hMcl-1 transgenic mouse with macrophage-specific overexpression of the human antiapoptotic Mcl-1 protein, a factor upregulated in AMs from patients at increased risk of community-acquired pneumonia, to address the requirement for apoptosis-associated killing. Measurements and Main Results: Wild-type and transgenic macrophages demonstrated comparable ingestion and initial phagolysosomal killing of bacteria. Continued ingestion (for ≥12 h) overwhelmed initial killing, and a second, late-phase microbicidal response killed viable bacteria in wild-type macrophages, but this response was blunted in CD68.hMcl-1 transgenic macrophages. The late phase of bacterial killing required both caspase-induced generation of mitochondrial reactive oxygen species and nitric oxide, the peak generation of which coincided with the late phase of killing. The CD68.hMcl-1 transgene prevented mitochondrial reactive oxygen species but not nitric oxide generation. Apoptosis-associated killing enhanced pulmonary clearance of Streptococcus pneumoniae and Haemophilus influenzae in wild-type mice but not CD68.hMcl-1 transgenic mice. Bacterial clearance was enhanced in vivo in CD68.hMcl-1 transgenic mice by reconstitution of apoptosis with BH3 mimetics or clodronate-encapsulated liposomes. Apoptosis-associated killing was not activated during Staphylococcus aureus lung infection. Conclusions: Mcl-1 upregulation prevents macrophage apoptosis-associated killing and establishes that apoptosis-associated killing is required to allow AMs to clear ingested bacteria. Engagement of macrophage apoptosis should be investigated as a novel, host-based antimicrobial strategy.


Assuntos
Apoptose/fisiologia , Macrófagos Alveolares/fisiologia , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Fagocitose/genética , Fagossomos/fisiologia , Pneumonia Bacteriana , Animais , Apoptose/efeitos dos fármacos , Bactérias , Compostos de Bifenilo/farmacologia , Caspases/metabolismo , Ácido Clodrônico/farmacologia , Modelos Animais de Doenças , Haemophilus influenzae , Humanos , Macrófagos Alveolares/metabolismo , Camundongos , Camundongos Transgênicos , Mitocôndrias/metabolismo , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Óxido Nítrico/metabolismo , Nitrofenóis/farmacologia , Piperazinas/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Staphylococcus aureus , Streptococcus pneumoniae , Sulfonamidas/farmacologia
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