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1.
Pediatr Hematol Oncol ; : 1-8, 2021 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-34369269

RESUMO

Hemophagocytic lymphohistiocytosis (HLH) is a syndrome of pathologic immune activation. It occurs because of severe inflammation due to uncontrolled proliferation of activated lymphocytes and histiocytes, characterized by the production of excessive levels of cytokines. Virus-associated HLH is a well-known entity, and parvovirus B19 is one of the common causes. Parvovirus B19 can also affect blood cell lineages. Therefore, HLH may be accompanied by several diseases such as cytopenia, aplastic anemia, and myelodysplastic syndrome. Herein, we report the case of a patient with hereditary spherocytosis who was diagnosed with parvovirus B19-induced HLH and aplastic crisis. A 7-year-old girl presented to our hospital with fever, pleural effusion, pancytopenia, hepatosplenomegaly, and hypotension. A bone marrow biopsy was performed under the suspicion of HLH, which revealed hemophagocytes. The diagnostic criteria for HLH were met, and prompt chemoimmunotherapy was initiated considering the clinically unstable situation. Her health improved rapidly after initiating treatment. Further study revealed that she had hereditary spherocytosis, and parvovirus B19 had caused aplastic crisis and HLH. The patient's clinical progress was excellent, and chemoimmunotherapy was reduced and discontinued at an early stage. This case shows that aplastic crisis and HLH can coexist with parvovirus B19 infection in patients with hereditary spherocytosis. Although the prognosis was good in this case of HLH caused by parvovirus B19, early detection and active treatment are essential.

2.
Blood Res ; 56(S1): S51-S64, 2021 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-33935036

RESUMO

Myelodysplastic syndromes (MDS) are a heterogeneous group of clonal hematological neoplasms characterized by ineffective hematopoiesis, morphologic dysplasia, and cytopenia. MDS overlap syndromes include various disorders, such as myelodysplastic/myeloproliferative neoplasms and hypoplastic MDS with aplastic anemia characteristics. MDS overlap syndromes share the characteristics of other diseases, which make differential diagnoses challenging. Advances in genomic studies have led to the discovery of frequent mutations in MDS and overlap syndromes; however, most of the mutations are not specific for the diagnosis of these diseases. The molecular characteristics of the overlap syndromes usually do not show a just "in-between" form but rather heterogeneous features. Established diagnostic criteria for these diseases based on clinical, morphologic, and laboratory features are still useful when combined with genomic data. It is expected that further studies for MDS and overlap syndromes will place emphasis on the roles of mutations as therapeutic targets and prognostic indicators.

3.
Leuk Res ; 79: 22-26, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30831479

RESUMO

We hypothesized that a subset of idiopathic cytopenia of undetermined significance (ICUS) is associated with an increased autonomous proliferation with exhaustion of hematopoiesis. The aim of this study was to investigate the cell turnover rate and replicative history of the bone marrow cells of ICUS patients. To this end, we examined telomere length (TL), proliferation, and apoptosis of the bone marrow cells of ICUS patients and healthy controls (HCs) using telomere quantitative fluorescence in situ hybridization and immunohistochemical staining for Ki-67 and cleaved caspase-3. We also performed targeted sequencing of 88 myeloid-associated genes. A total of 37 patients with ICUS were enrolled in this study, with a median age of 66 years (range: 31-83). TLs were significantly shorter in patients with ICUS than in the HCs (8.8, interquartile range [IQR] 6.8-12.1 vs 18.4, IQR 14.4-22.0, p < 0.0001). Proliferation (Ki-67-positive) and apoptosis (cleaved caspase-3-positive) were significantly increased in patients with ICUS compared to HCs (median = 20.0% vs 5.0%, p = 0.0003; 45.0% vs 22.5%, p = 0.0005, respectively). The shortening of TL and the increased proliferation and apoptotic activity was also prominent in patients with ICUS without mutation and dysplasia than in HCs (p < 0.0001, p < 0.0001, and p = 0.0093, respectively). TL was not associated with mutational profile and clinical characteristics as well in patients with ICUS. To our knowledge, this is the first study to show that ICUS is associated with premature replicative senescence with increased proliferation and apoptosis of bone marrow cells. Further study is needed to address the cause of replicative exhaustion in ICUS patients.


Assuntos
Senescência Celular/fisiologia , Células-Tronco Hematopoéticas/fisiologia , Síndromes Mielodisplásicas/fisiopatologia , Trombocitopenia/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Hematopoese/fisiologia , Humanos , Hibridização in Situ Fluorescente , Masculino , Pessoa de Meia-Idade , Mutação , Síndromes Mielodisplásicas/complicações , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/patologia , Telômero/fisiologia , Encurtamento do Telômero/fisiologia , Trombocitopenia/complicações , Trombocitopenia/genética , Trombocitopenia/patologia
4.
Biopreserv Biobank ; 17(4): 319-325, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30888199

RESUMO

Precision medicine has received increased attention as an effective approach for the treatment of cancer patients. Because of challenges associated with the availability of archived tissue, liquid biopsies are often performed to detect cancer-specific mutations. One of the major advantages of the liquid biopsy is that the treatment can be monitored longitudinally, even after the tumor tissue is no longer available. In a clinical setting, one component of precision medicine is the detection of cancer-specific mutations using archived samples. In this study, we evaluated the epidermal growth factor receptor (EGFR) mutation status of samples of lung cancer patients stored before introduction of the plasma EGFR test at our institution. The aim of this study was to validate the utility of archived plasma samples for detection of the EGFR mutation in nonsmall cell lung cancer (NSCLC) patients. The Cobas® EGFR Mutation Test v2 was the first liquid biopsy test approved as a companion diagnostic test for patients with NSCLC treated with tyrosine kinase inhibitors. We tested for the EGFR mutation in 116 plasma samples archived in the biobank, and the results were compared with those obtained in the tissue or cytology EGFR mutation test. The EGFR mutation-positive rate from archived plasma was lower than that determined from tissue or cytology at 19.0% and 53.4%, respectively, and the concordance rate between the two tests was 58.6%. Of interest, five (4.3%) samples showed the T790M mutation in the plasma test, whereas this mutation was only detected in two (1.7%) tissue/cytology samples. Five (4.3%) samples were additionally positive in the plasma test. Overall, these results indicate that archived plasma samples can serve as an alternative source for the plasma EGFR mutation test when tissue samples are not available, and can improve precision medicine and long-term follow-up in a noninvasive manner.


Assuntos
Bancos de Espécimes Biológicos , Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Pulmonares/genética , Mutação/genética , Plasma , Adulto , Idoso , Idoso de 80 Anos ou mais , Receptores ErbB/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medicina de Precisão
5.
Oncol Rep ; 41(5): 3119-3126, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30864724

RESUMO

Redd1 is a stress response protein that functions as a repressor of mTORC1, a central regulator of protein translation, resulting in the inhibition of cell growth and metabolism. However, paradoxically, high Redd1 expression favors cancer progression and generates resistance to cancer therapy. Herein, we revealed that constitutive overexpression of Redd1 induced HSP27 and HSP70 expression in lung cancer cells. The expression of Redd1, HSP27 and HSP70 was highly increased in lung cancer tissues compared with that in normal lung tissues. Inhibition of HSP27 or HSP70 suppressed AKT phosphorylation, which was induced by constitutive overexpression of Redd1 and enhanced the inhibitory effects on viability of Redd1­overexpressing cells. Inhibition of AKT phosphorylation resulted in a decrease of HSP27 and HSP70 expression in Redd1­overexpressing cells. These data indicated that HSPs and AKT in Redd1­overexpressing cells positively regulated the function and expression of each other and were involved in lung cancer cell survival. Knockdown of HSP27, HSP70 or AKT enhanced ionizing radiation (IR) sensitivity, particularly in lung cancer cells in which Redd1 was stably overexpressed. Collectively, constitutive overexpression of Redd1 led to HSP27 and HSP70 induction and AKT activation, which were involved in lung cancer cell survival and resistance to IR, suggesting that Redd1 may be used as a therapeutic target for lung cancer.


Assuntos
Proteínas de Choque Térmico HSP27/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Neoplasias Pulmonares/radioterapia , Tolerância a Radiação , Fatores de Transcrição/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos da radiação , Proteínas de Choque Térmico , Humanos , Pulmão/patologia , Neoplasias Pulmonares/patologia , Chaperonas Moleculares , Fosforilação , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Interferente Pequeno/metabolismo , Radiação Ionizante , Transdução de Sinais/efeitos da radiação , Fatores de Transcrição/genética
6.
Leuk Lymphoma ; 60(4): 1053-1061, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30714451

RESUMO

A revised WHO classification of hematopoietic neoplasm introduced the new category 'Myeloid Neoplasms with Germline Predisposition', reflecting the growing importance of genetic testing for myeloid neoplasms. Here, we investigated monozygotic twins with the same de novo mutation in GATA2 but different phenotypes. The patient suffering a bleeding tendency was diagnosed with myelodysplastic syndrome (MDS), and her monozygotic twin showed dysmegakaryopoietic features in the bone marrow. Targeted sequencing revealed the same germline mutation in GATA2, c.1192C > T, in both sisters and different somatic mutations in 14 genes between the sisters. The GATA2 mutation was absent in both parents, and their hemograms were normal. The methylation profile of the GATA2 promoter region was different between the twins, showing denser promoter methylation in the patient, correlated with MDS. Thus, we concluded that the twins had acquired a de novo GATA2 mutation but showed different phenotypes, possibly due to the critical role of epigenetic changes.


Assuntos
Metilação de DNA , Fator de Transcrição GATA2/genética , Mutação , Fenótipo , Regiões Promotoras Genéticas , Gêmeos Monozigóticos , Adulto , Medula Óssea/patologia , Análise Citogenética , Feminino , Testes Genéticos , Mutação em Linhagem Germinativa , Humanos , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/genética , Síndromes Mielodisplásicas/diagnóstico , Síndromes Mielodisplásicas/genética , Linhagem
7.
Am J Clin Pathol ; 151(4): 416-423, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30561492

RESUMO

OBJECTIVES: Diagnosis of central nervous system involvement in acute lymphoblastic leukemia (ALL) requires morphologic expertise; therefore, we evaluated interphase fluorescence in situ hybridization (iFISH) of cerebrospinal fluid (CSF) cytospin preparations as a potential complementary test. METHODS: Twenty-three CSF cytospin specimens from 13 pediatric patients with ALL were included. iFISH probes detecting BCR-ABL1, ETV6-RUNX1, and KMT2A rearrangement and CDKN2A deletion, which were present at initial diagnosis, were used on follow-up CSF cytospin specimens and were compared with cytology. RESULTS: Seventeen (73.9%) follow-up specimens showed concordant results between iFISH and cytology. Two (8.7%) samples with discordant results were positive by iFISH but not by cytology; one (4.3%) was positive only by cytology. In the remaining three (13.0%) specimens, too few cells were available for cytology, whereas iFISH interpretation was possible. CONCLUSIONS: iFISH of CSF cytospin preparations improves malignant cell detection in pediatric ALL.


Assuntos
Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Adolescente , Criança , Pré-Escolar , Análise Citogenética , Feminino , Seguimentos , Humanos , Hibridização in Situ Fluorescente , Lactente , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/líquido cefalorraquidiano , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia
8.
Clin Lab ; 64(9): 1573-1579, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-30273999

RESUMO

BACKGROUND: This study aimed to investigate the detection of methylated Septin 9 (mSEPT9) in Korean patients with colorectal cancer (CRC) and compare the results with those of previous studies. METHODS: A total of 127 plasma samples (111 patients with untreated CRC, 5 patients with adenomas, and 11 CRC patients treated with concurrent chemoradiotherapy before surgery) were collected. mSEPT9 was measured qualitatively with the Abbott RealTime ms9 Colorectal Cancer Assay. RESULTS: mSEPT9 was detected in 44 of 111 (39.6%) cases of untreated CRC but was not detected in the adenoma cases. The difference in the sensitivity of mSEPT9 among patients with adenomas and those with each stage of untreated CRC was statistically significant (Dukes' staging, p = 0.002 and TNM staging, p = 0.008). The sensitivity of mSEPT9 for each of the stages (I - IV) of untreated CRC patients were 20.7%, 54.1%, 36.6%, and 75.0%, respectively. The positive mSEPT9 results in untreated CRC patients reverted to negative in 19 of 21 patients (90.5%) after treatment. CONCLUSIONS: Compared to previous studies, the overall sensitivity of mSEPT9 was lower, but similar patterns were found in the sensitivities for each stage. Additionally, mSEPT9 appeared to have potential as a monitoring tool for CRC.


Assuntos
Adenoma/genética , Biomarcadores Tumorais/genética , Neoplasias Colorretais/genética , Metilação de DNA , Septinas/genética , Adenoma/etnologia , Adenoma/patologia , Adenoma/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Grupo com Ancestrais do Continente Asiático/genética , Neoplasias Colorretais/etnologia , Neoplasias Colorretais/patologia , Neoplasias Colorretais/terapia , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Fenótipo , Valor Preditivo dos Testes , Estudos Prospectivos , Reação em Cadeia da Polimerase em Tempo Real , República da Coreia/epidemiologia
10.
Biochem Biophys Res Commun ; 486(4): 1083-1089, 2017 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-28377224

RESUMO

HER family receptors are frequently deregulated in breast cancer and the deregulation of these receptors is associated with poor prognosis. Thus, these receptors are considered therapeutic targets. In the present study, we found that piperlongumine (PL) downregulates the expression of HER family receptors HER1, HER2, and HER3 in breast cancer cells. Downregulation of these receptors by PL is mediated through the generation of reactive oxygen species (ROS), as N-acetyl-cysteine blocks it. Interestingly, the HER2-overexpressing cell lines BT474 and SkBr3 are somewhat more sensitive to PL than the low HER2-expressing cell line MCF7. In addition, the overexpression of HER2 increases the sensitivity of MCF7 cells to PL. Collectively, our data indicate the therapeutic potential of PL in the treatment of breast cancer.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Dioxolanos/administração & dosagem , Receptores ErbB/biossíntese , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Antineoplásicos/administração & dosagem , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Humanos , Células MCF-7
11.
Sci Rep ; 6: 28945, 2016 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-27358039

RESUMO

As the activation of autophagy contributes to the efficacy of many anticancer therapies, deciphering the precise role of autophagy in cancer therapy is critical. Here, we report that the dual mTORC1/2 inhibitors PP242 and OSI-027 decreased cell viability but did not induce apoptosis in the non-small cell lung cancer (NSCLC) cell lines H460 and A549. PP242 induced autophagy in NSCLC cells as demonstrated by the formation of massive vacuoles and acidic vesicular organelles and the accumulation of LC3-II. JNK was activated by PP242, and PP242-induced autophagy was blocked by inhibiting JNK pathway with SP600125 or JNK siRNA, suggesting that JNK activation is required for the mTORC1/2 inhibitor-mediated induction of autophagy in NSCLC cells. Inhibiting JNK or autophagy increased the sensitivity of H460 cells to mTORC1/2 inhibitors, indicating that JNK or autophagy promoted survival in NSCLC cells treated with mTORC1/2 inhibitors. Together, these data suggest that combining mTORC1/2 inhibitors with inhibitors of JNK or autophagy might be an effective approach for improving therapeutic outcomes in NSCLC.


Assuntos
Autofagia/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/patologia , MAP Quinase Quinase 4/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/antagonistas & inibidores , Alvo Mecanístico do Complexo 2 de Rapamicina/antagonistas & inibidores , Antineoplásicos/metabolismo , Linhagem Celular Tumoral , Inibidores Enzimáticos/metabolismo , Humanos , Imidazóis/metabolismo , Indóis/metabolismo , Purinas/metabolismo , Triazinas/metabolismo
13.
Oncol Lett ; 10(2): 829-834, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26622578

RESUMO

Breast cancer cells possess a deregulated apoptotic pathway with increased expression levels of anti-apoptotic B-cell lymphoma-2 (Bcl-2) family proteins and ribosomal S6 kinase 1 (S6K1) protein activity. Therefore, combined interference of anti-apoptotic Bcl-2 family and S6K1 protein expression may be a reasonable therapeutic strategy for the treatment of patients with breast cancer. In the present study, it was identified that the administration of a combination of ABT263 [navitoclax; a Bcl-2/Bcl-extra large (Bcl-xL) inhibitor] and PF4708671 (an S6K1 inhibitor) markedly increased apoptotic cell death in the BT474 breast cancer cells compared with the administration of either agent alone. Furthermore, the downregulation of Bcl-2/Bcl-xL and S6K1 with small interfering RNA induced a significant increase in cell death compared with RNA interference of either agent alone. Notably, combination treatment with ABT263 and PF4708671 decreased the expression level of survivin protein, with this ectopic expression of survivin attenuating cell death. Thus, the present study determined that the combined inhibition of Bcl-2/Bcl-xL and S6K1 may be a good strategy for treating patients with breast cancer.

15.
Toxicol Appl Pharmacol ; 287(1): 17-25, 2015 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-25981168

RESUMO

Despite excellent initial clinical responses of non-small cell lung cancer (NSCLC) patients to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs), many patients eventually develop resistance. According to a recent report, vacuolar H+ ATPase (vATPase) is overexpressed and is associated with chemotherapy drug resistance in NSCLC. We investigated the combined effects of EGFR TKIs and vATPase inhibitors and their underlying mechanisms in the regulation of NSCLC cell death. We found that combined treatment with EGFR TKIs (erlotinib, gefitinib, or lapatinib) and vATPase inhibitors (bafilomycin A1 or concanamycin A) enhanced synergistic cell death compared to treatments with each drug alone. Treatment with bafilomycin A1 or concanamycin A led to the induction of Bnip3 expression in an Hif-1α dependent manner. Knock-down of Hif-1α or Bnip3 by siRNA further enhanced cell death induced by bafilomycin A1, suggesting that Hif-1α/Bnip3 induction promoted resistance to cell death induced by the vATPase inhibitors. EGFR TKIs suppressed Hif-1α and Bnip3 expression induced by the vATPase inhibitors, suggesting that they enhanced the sensitivity of the cells to these inhibitors by decreasing Hif-1α/Bnip3 expression. Taken together, we conclude that EGFR TKIs enhance the sensitivity of NSCLC cells to vATPase inhibitors by decreasing Hif-1α/Bnip3 expression. We suggest that combined treatment with EGFR TKIs and vATPase inhibitors is potentially effective for the treatment of NSCLC.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Carcinoma Pulmonar de Células não Pequenas/enzimologia , Receptores ErbB/antagonistas & inibidores , Neoplasias Pulmonares/enzimologia , ATPases Vacuolares Próton-Translocadoras/antagonistas & inibidores , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Resistencia a Medicamentos Antineoplásicos , Receptores ErbB/metabolismo , Cloridrato de Erlotinib , Gefitinibe , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Lapatinib , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Macrolídeos/farmacologia , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Quinazolinas/farmacologia , Interferência de RNA , Transfecção , ATPases Vacuolares Próton-Translocadoras/metabolismo
16.
Ann Clin Lab Sci ; 45(2): 193-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25887874

RESUMO

We report three cases of plasma cell myeloma with obscure and discordant data for a monoclonal component. In this study, the results of serum heavy/light chain (sHLC) were retrospectively compared with those of conventional methods during disease monitoring. All three patients achieved a complete response and experienced a relapse during follow-up, and the sHLC ratio allowed early prediction of disease relapse and correlated well with other electrophoretic methods compared with the free light chain ratio. Therefore, we suggest that the sHLC assay may be useful as a complementary tool; it has a good correlation with conventional methods and sensitivity in assessing disease status and treatment response in patients with plasma cell myeloma.


Assuntos
Cadeias Pesadas de Imunoglobulinas/sangue , Cadeias Leves de Imunoglobulina/sangue , Monitorização Fisiológica/métodos , Mieloma Múltiplo/sangue , Plasmócitos/patologia , Adulto , Idoso , Feminino , Humanos , Masculino
17.
Mol Cells ; 38(4): 327-35, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25813625

RESUMO

Piperlongumine, a natural alkaloid isolated from the long pepper, selectively increases reactive oxygen species production and apoptotic cell death in cancer cells but not in normal cells. However, the molecular mechanism underlying piperlongumine-induced selective killing of cancer cells remains unclear. In the present study, we observed that human breast cancer MCF-7 cells are sensitive to piperlongumine-induced apoptosis relative to human MCF-10A breast epithelial cells. Interestingly, this opposing effect of piperlongumine appears to be mediated by heme oxygenase-1 (HO-1). Piperlongumine upregulated HO-1 expression through the activation of nuclear factor-erythroid-2-related factor-2 (Nrf2) signaling in both MCF-7 and MCF-10A cells. However, knockdown of HO-1 expression and pharmacological inhibition of its activity abolished the ability of piperlongumine to induce apoptosis in MCF-7 cells, whereas those promoted apoptosis in MCF-10A cells, indicating that HO-1 has anti-tumor functions in cancer cells but cytoprotective functions in normal cells. Moreover, it was found that piperlongumine-induced Nrf2 activation, HO-1 expression and cancer cell apoptosis are not dependent on the generation of reactive oxygen species. Instead, piperlongumine, which bears electrophilic α,ß-unsaturated carbonyl groups, appears to inactivate Kelch-like ECH-associated protein-1 (Keap1) through thiol modification, thereby activating the Nrf2/HO-1 pathway and subsequently upregulating HO-1 expression, which accounts for piperlongumine-induced apoptosis in cancer cells. Taken together, these findings suggest that direct interaction of piperlongumine with Keap1 leads to the upregulation of Nrf2-mediated HO-1 expression, and HO-1 determines the differential response of breast normal cells and cancer cells to piperlongumine.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/enzimologia , Dioxolanos/farmacologia , Heme Oxigenase-1/metabolismo , Apoptose/efeitos dos fármacos , Neoplasias da Mama/patologia , Indução Enzimática/efeitos dos fármacos , Feminino , Humanos , Células MCF-7 , Fator 2 Relacionado a NF-E2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
18.
J Cancer Res Clin Oncol ; 140(12): 2039-46, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25023940

RESUMO

PURPOSE: Piperlongumine (PL) has been shown to selectively induce apoptotic cell death in cancer cells via reactive oxygen species (ROS) accumulation. In this study, we characterized a molecular mechanism for PL-induced cell death. METHODS: Cell viability and cell death were assessed by MTT assay and Annexin V-FITC/PI staining, respectively. ROS generation was measured using the H2DCFDA. Small interfering RNA (siRNA) was used for suppressing gene expression. The mRNA and protein expression were analyzed by RT-PCR and Western blot analysis, respectively. RESULTS: We found that PL promotes C/EBP homologous protein (CHOP) induction, which leads to the up-regulation of its targets Bim and DR5. Pretreatment with the ROS scavenger N-acetyl-cysteine abolishes the PL-induced up-regulation of CHOP and its target genes, suggesting an essential role for ROS in PL-induced CHOP activation. The down-regulation of CHOP or Bim with siRNA efficiently attenuates PL-induced cell death, suggesting a critical role for CHOP in this cell death. Furthermore, PL potentiates TRAIL-induced cytotoxicity in breast cancer cells by upregulating DR5, as DR5 knockdown abolished the sensitizing effect of PL on TRAIL responses. CONCLUSIONS: Overall, our data suggest a new mechanism for the PL-induced cell death in which ROS mediates CHOP activation, and combination treatment with PL and TRAIL could be a potential strategy for breast cancer therapy.


Assuntos
Apoptose/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Dioxolanos/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/farmacologia , Fator de Transcrição CHOP/metabolismo , Proteínas Reguladoras de Apoptose/fisiologia , Proteína 11 Semelhante a Bcl-2 , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Feminino , Humanos , Proteínas de Membrana/fisiologia , Proteínas Proto-Oncogênicas/fisiologia , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/fisiologia
19.
Biomed Rep ; 2(5): 737-742, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25054020

RESUMO

Lung cancer is one of the main causes of cancer-related mortality. The identification of early diagnostic biomarkers improved outcomes for lung cancer patients. Serum fibrin-fibrinogen degradation products (FDP) levels are elevated in numerous malignancies due to hemostatic alterations. The serum FDP levels were compared to the levels of cytokeratin 19 fragment antigen (CYFRA 21-1), another well-established biomarker. The serum samples from 193 lung cancer patients, 84 healthy controls and 106 patients with benign respiratory diseases were obtained. The serum FDP level was measured using the DR-70 immunoassay and the CYFRA 21-1 level was measured by electrochemiluminescence using the Roche Analytics E170. Receiver operating characteristics curves were used to assess the predictive sensitivity and specificity. The mean serum FDP level in lung cancer patients (35.01±229.02 µg/ml) was significantly higher compared to the 190 non-cancerous subjects (0.60±0.75 µg/ml; P=0.039). The mean serum CYFRA 21-1 level in lung cancer patients (4.50±6.67 ng/ml) was also significantly higher compared to the non-cancerous subjects (1.40±0.83 ng/ml; P<0.05). FDP exhibited clinical sensitivity and specificity of 86 and 75%, respectively, at an optimal cut-off at 0.67 µg/ml. CYFRA 21-1 exhibited clinical sensitivity and specificity of 77 and 74%, respectively, at a cut-off of 1.65 ng/ml. The serum FDP area under the curve (0.87) was slightly higher compared to CYFRA 21-1 (0.83). Therefore, it is apparent that serum FDP is comparable to CYFRA 21-1 as a lung cancer biomarker and can be used for clinical practice.

20.
Springerplus ; 3: 76, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24567882

RESUMO

Extraction of high-quality RNA is a crucial step in gene expression profiling. To achieve optimal RNA extraction from frozen blood, the performance of three RNA extraction kits- TRI reagent, PAXgene blood RNA system (PAXgene) and NucleoSpin RNA blood kit (NucleoSpin)- was evaluated. Fifteen blood specimens collected in tubes containing potassium ethylenediaminetetraacetic acid (EDTA) and stored at -80°C for approximately 5 years were randomly selected. The yield and purity of RNA, RIN (RNA integrity number) values and cycle threshold (Ct) values were assessed. Mean RNA yields with TRI reagent, PAXgene and NucleoSpin were 15.6 ± 8.7 µg/ml, 3.1 ± 1.7 µg/ml and 9.0 ± 5.5 µg/ml, respectively. Mean A260/280 ratios of RNA for the three kits were 1.7 ± 0.1, 2.0 ± 0.1, and 2.0 ± 0.0, and mean RIN values recorded as 3.2 ± 0.8, 6.0 ± 1.1, and 6.4 ± 0.9, respectively. The Ct values of housekeeping genes, 18S rRNA, ß-actin, RPLP0 and HPRT1, were as follows: TRI reagent (19.2 ± 1.6, 30.6 ± 1.8, 29.9 ± 1.4 and 36.3 ± 1.3), PAXgene 16.6 ± 1.4, 26.4 ± 1.3, 28.2 ± 1.8 and 33.8 ± 1.1), and NucleoSpin (16.3 ± 1.5, 27.2 ± 1.3, 27.0 ± 1.6 and 32.9 ± 1.6). RNA yield using TRI reagent was 1.7 times higher than that with NucleoSpin and 5 times higher than that with PAXgene. However, the purity and integrity of TRI-extracted RNA was lower than that extracted with PAXgene and NucleoSpin. Moreover, the Ct values of housekeeping genes after extraction with TRI reagent were approximately 1.7-3.8 times higher than those obtained with PAXgene and NucleoSpin. The PAXgene and NucleoSpin kits produced similar results in terms of RNA purity and integrity and subsequent gene amplification. However, RNA yields from NucleoSpin were 2.9-fold higher, compared to PAXgene. Based on these findings, we conclude that NucleoSpin is the most effective kit for extraction of abundant and high-quality RNA from frozen blood.

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