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1.
Int J Cancer ; 142(2): 308-321, 2018 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-28921929

RESUMO

The frequently dysregulated Wnt/ß-catenin signaling in different malignancies, by activation of its own or orchestration with other co-factors, regulates various oncogenic or tumor-suppressive genes. Among these genes, miRNAs, which are negative posttranscriptional regulators, are also embedded in the Wnt signaling network. Different from the Wnt-induced oncogenic miRNAs, the specific mechanism underlying the Wnt-repressed tumor-suppressive miRNAs is much less understood. In our study, firstly by analyzing a ChIP-seq dataset against TCF4, the core transcription factor for initiation of Wnt signaling in colorectal cancer (CRC) cells, we screened out several tumor-suppressive miRNAs potentially regulated by Wnt signaling. Then through siRNA-mediated knock-down tests and protein and chromatin immunoprecipitations, we found the TCF4-ß-catenin complex can recruit the histone trimethylation complex PRC2 as a co-repressor while binding to the TCF4-binding element (TBE) in the promoter regions of miR-145, miR-132 and miR-212. Thus, upon Wnt signaling activation, the PRC2-mediated trimethylation of histone H3 at lysine 27 increases at these promoter regions, leading to decreased miRNA levels. Furthermore, we found that by targeting TCF4 and SUZ12, the key components of the negative regulation complexes, the tumor-suppressive miR-145 co-repressed by Wnt signaling and histone trimethylation, forms double-negative regulation loops with its negative regulators in CRC cells. And the inverse associations between miR-145 and its targets/negative regulators have also been demonstrated in nude mice and clinical samples. Collectively, we elucidated the detailed molecular mechanism of how dysregulated Wnt/ß-catenin signaling and tumor-suppressive miRNAs reciprocally regulate each other in CRC cells.


Assuntos
Neoplasias Colorretais/patologia , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas/secundário , MicroRNAs/genética , Complexo Repressor Polycomb 2/metabolismo , Fator de Transcrição 4/metabolismo , beta Catenina/metabolismo , Animais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Metástase Linfática , Masculino , Camundongos , Camundongos Nus , Estadiamento de Neoplasias , Complexo Repressor Polycomb 2/genética , Fator de Transcrição 4/genética , Ensaios Antitumorais Modelo de Xenoenxerto , beta Catenina/genética
2.
Med Sci Monit ; 24: 2541-2549, 2018 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-29694335

RESUMO

BACKGROUND Histone H2A deubiquitinase MYSM1 has recently been shown to be essential for hematopoiesis and hematopoietic stem cell (HSC) function in both mice and humans. However, conventional MYSM1 knockouts cause partial embryonic lethality and growth retardation, and it is difficult to convincingly remove the effects of environmental factors on HSC differentiation and function. MATERIAL AND METHODS MYSM1 conditional knockout (cKO) mice were efficiently induced by using the Vav1-cre transgenic system. The Vav-Cre MYSM1 cKO mice were then analyzed to verify the intrinsic role of MYSM1 in hematopoietic cells. RESULTS MYSM1 cKO mice were viable and were born at normal litter sizes. At steady state, we observed a defect in hematopoiesis, including reduced bone marrow cellularity and abnormal HSC function. MYSM1 deletion drives HSCs from quiescence into rapid cycling, and MYSM1-deficient HSCs display impaired engraftment. In particular, the immature cycling cKO HSCs have elevated reactive oxygen species (ROS) levels and are prone to apoptosis, resulting in the exhaustion of the stem cell pool during stress response to 5-FU. CONCLUSIONS Our study using MYSM1 cKO mice confirms the important role of MYSM1 in maintaining HSC quiescence and survival.


Assuntos
Endopeptidases/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Animais , Apoptose/fisiologia , Diferenciação Celular/fisiologia , Divisão Celular , Sobrevivência Celular/genética , Endopeptidases/genética , Hematopoese , Células-Tronco Hematopoéticas/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Espécies Reativas de Oxigênio/metabolismo , Transativadores , Proteases Específicas de Ubiquitina
3.
BMC Infect Dis ; 17(1): 310, 2017 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-28446129

RESUMO

BACKGROUND: Known predictors of neurosyphilis were mainly drawn from human immunodeficiency virus (HIV)-infected syphilis patients, which may not be applicable to HIV-negative populations as they have different characteristics, particularly those with neurological symptoms. This study aimed to identify novel predictors of HIV-negative symptomatic neurosyphilis (S-NS). METHODS: From June 2005 to June 2015, 370 HIV-negative syphilis patients with neurological symptoms were recruited, consisting of 191 S-NS patients (including 123 confirmed neurosyphilis and 68 probable neurosyphilis patients) and 179 syphilis/non-neurosyphilis (N-NS) patients. Clinical and laboratory characteristics of S-NS were compared with N-NS to identify factors predictive of S-NS. Serum rapid plasma reagin (RPR), Treponema pallidum particle agglutination (TPPA), and their parallel testing format for screening S-NS were evaluated. RESULTS: The likelihood of S-NS was positively associated with the serum RPR and TPPA titers. The serum TPPA titers performed better than the serum RPR titers in screening S-NS. The optimal cut-off points to recognize S-NS were serum RPR titer ≥1:4 and serum TPPA titer ≥1:2560 respectively. A parallel testing format of a serum RPR titer ≥1:2 and serum TPPA titer ≥1:1280 screened out 95.8% of S-NS and all confirmed cases of neurosyphilis. S-NS was independently associated with male sex, serum RPR titer ≥1:4, serum TPPA titer ≥1:2560, and elevated serum creatine kinase. Concurrence of these factors increased the likelihood of S-NS. CONCLUSIONS: Quantitation of serum TPPA is worthwhile and performs better than serum RPR in screening S-NS. Serum RPR, serum TPPA, male sex, and serum creatine kinase can predict S-NS. Moreover, patients with both a serum RPR titer <1:2 and a serum TPPA titer <1:1280 have a low probability of S-NS, suggesting that it is reasonable to reduce lumbar punctures in such individuals.


Assuntos
Neurossífilis/diagnóstico , Neurossífilis/etiologia , Testes de Aglutinação/métodos , Feminino , Soropositividade para HIV , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Fatores de Risco , Punção Espinal , Sífilis/complicações , Sorodiagnóstico da Sífilis , Treponema pallidum/patogenicidade
4.
Biol Trace Elem Res ; 202(7): 3062-3072, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38273185

RESUMO

Chronic obstructive pulmonary disease (COPD) is now considered among the top three contributors to mortality globally. There is limited understanding surrounding the contribution of magnesium to the progression of COPD. This survey aims to evaluate the connection between dietary magnesium intake and both lung function and COPD prevalence among the US population. The research comprised 4865 participants in the National Health and Nutrition Examination Survey (NHANES) program conducted from 2007 to 2012. To evaluate the association between dietary magnesium intake and lung function as well as COPD, the study conducted multiple regression analyses, stratified analyses, and smoothed curves. In this study, we explored the relationship between higher magnesium intake and higher FEV1 [ß = 0.21 (95% CI 0.12, 0.30)] and FVC [ß = 0.25 (95% CI 0.14, 0.36)] after accounting for all potential confounding factors. We demonstrated a relationship between increased magnesium intake and reduced odds of developing COPD [OR = 0.9993 (95% CI 0.9987, 1.0000)]. The results of stratified analyses further indicated that the relationship between magnesium intake and the risk of COPD is more pronounced in the 40-60 age group and males. The study demonstrated positive associations between the intake of dietary magnesium and both FEV1 and FVC. Additionally, an adverse relationship between magnesium intake and the prevalence of COPD was also observed, suggesting that supplementation with magnesium may be a practical approach to preventing and managing COPD.


Assuntos
Magnésio , Doença Pulmonar Obstrutiva Crônica , Humanos , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Magnésio/administração & dosagem , Masculino , Pessoa de Meia-Idade , Estudos Transversais , Feminino , Adulto , Estados Unidos/epidemiologia , Inquéritos Nutricionais , Pulmão/fisiopatologia , Pulmão/efeitos dos fármacos , Idoso , Dieta , Testes de Função Respiratória , Volume Expiratório Forçado
5.
Biochem Biophys Res Commun ; 441(1): 191-5, 2013 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-24140062

RESUMO

Cu/Zn superoxide dismutase (SOD1) is a key antioxidant enzyme. Deficiency of SOD1 is associated with various human diseases, including cancer. Here, we report that SOD1 is succinylated and that succinylation decreases its activity. SIRT5 binds to, desuccinylates and activates SOD1. SOD1-mediated ROS reduction is increased when SIRT5 is co-expressed. Furthermore, mutation of the SOD1 succinylation site inhibits the growth of lung tumor cells. These results reveal a novel post-translational regulation of SOD1 by means of succinylation and SIRT5-dependent desuccinylation, which is important for the growth of lung tumor cells.


Assuntos
Espécies Reativas de Oxigênio/metabolismo , Sirtuínas/metabolismo , Succinatos/metabolismo , Superóxido Dismutase/metabolismo , Sequência de Aminoácidos , Biocatálise , Linhagem Celular Tumoral , Proliferação de Células , Ativação Enzimática , Humanos , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/patologia , Lisina/metabolismo , Dados de Sequência Molecular , Mutação/genética , Ligação Proteica , Superóxido Dismutase/química , Superóxido Dismutase-1
6.
Contemp Oncol (Pozn) ; 17(2): 210-3, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23788993

RESUMO

Sarcomatoid carcinoma (SC) is a rare primary malignant tumor in which both carcinomatous and sarcomatous elements occur. It can occur in many different organs and anatomical locations, such as the skin, thyroid gland, bone, urinary tract, breast, pancreas, liver and other areas. Of them, pulmonary sarcomatoid carcinoma (PSC) is a rare malignant cancer composed of sarcoma and sarcoma-like tumors with spindle or giant cell features. Here a case of a 75-year-old Chinese man with a six-month history of cough and hemoptysis is reported. Chest X-ray showed a tumor shadow in the left lung field. Chest computed tomography (CT) scan showed a lobulated mass in his left hilum and even the left pulmonary artery. Pleomorphic interstitial cells were found by bronchoscopic brushing. To establish a definitive diagnosis for PSC, a left pneumonectomy was performed. The pathological stage was IIB (pT2N1M0) based on the tumor node metastasis (TNM) staging system. The tumor's pathology, histology, immunohistochemistry and treatment methods are discussed.

7.
Gastroenterol Rep (Oxf) ; 11: goad022, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37124071

RESUMO

Background: The study purpose was to characterize the mycobiome and its associations with the expression of pathogenic genes in esophageal squamous cell carcinoma (ESCC). Methods: Patients with primary ESCC were recruited from two central hospitals. We performed internal transcribed spacer 1 (ITS1) ribosomal DNA sequencing analysis. We compared differential fungi and explored the ecology of fungi and the interaction of bacteria and fungi. Results: The mycobiota diversity was significantly different between tumors and tumor-adjacent samples. We further analysed the differences between the two groups, at the species level, confirming that Rhodotorula toruloides, Malassezia dermatis, Hanseniaspora lachancei, and Spegazzinia tessarthra were excessively colonized in the tumor samples, whereas Preussia persica, Fusarium solani, Nigrospora oryzae, Acremonium furcatum, Golovinomyces artemisiae, and Tausonia pullulans were significantly more abundant in tumor-adjacent samples. The fungal co-occurrence network in tumor-adjacent samples was larger and denser than that in tumors. Similarly, the more complex bacterial-fungal interactions in tumor-adjacent samples were also detected. The expression of mechanistic target of rapamycin kinase was positively correlated with the abundance of N. oryzae and T. pullulans in tumor-adjacent samples. In tumors, the expression of MET proto-oncogene, receptor tyrosine kinase (MET) had a negative correlation and a positive correlation with the abundance of R. toruloides and S. tessarthra, respectively. Conclusion: This study revealed the landscape of the esophageal mycobiome characterized by an altered fungal composition and bacterial and fungal ecology in ESCC.

9.
Opt Express ; 18(3): 1794-800, 2010 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-20174008

RESUMO

A novel angular probe using the Fabry-Perot etalon and angular scanning technique is proposed for absolute angular displacement determinations in this paper. The measurement theory is first derived, a setup constructed to implement the angular probe is then introduced and analyzed, and the experimental results from the uses of the setup are finally presented. The setup analyses reveal that the probe is with high measurement resolution and sensitivity. The experimental results not only confirm the validity, stability, accuracy, and repeatability, but also show an application of the angular probe.

10.
Cancer Med ; 8(4): 1694-1709, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30791232

RESUMO

Human colorectal cancer (CRC), characterized by its high morbidity and lethality, seriously threatens human health and lives. MicroRNA-487b (miR-487b) is currently reported to be aberrantly expressed in several tumors, but the detailed functions and underlying mechanisms of miR-487b in CRC remain unclear. Here, we found that miR-487b is downregulated in CRC cell lines and is markedly decreased in tumor specimens derived from CRC patients. MiR-487b inhibits cell proliferation, migration and invasion and promotes the apoptosis of CRC cells in vitro. Statistical analysis of clinical samples indicates that miR-487b may serve as a biomarker for early CRC diagnosis. Inverse correlations between the expression levels of MYC, SUZ12, and KRAS and that of miR-487b exist in vitro and in CRC patient tissue specimens. Further experiments demonstrated the regulatory effects of miR-487b on MYC, SUZ12, and KRAS, and the disruption of these genes partially restores the miR-487b inhibitor-induced phenotype. Additionally, miR-487b promoter region is in a DNA hypermethylated condition and the DNA methyltransferase inhibitor 5-aza-2'-deoxycytidine (5-Aza) increases the levels of miR-487b but suppresses the expression of MYC, SUZ12, and KRAS in a time- and concentration-dependent manner in CRC cells. Collectively, miR-487b is regulated by DNA methylation and it functions as a tumor suppressor in CRC mainly through targeting MYC, SUZ12, and KRAS. Our study provides insight into the regulatory network in CRC cells, offering a new target for treating CRC patients.


Assuntos
Neoplasias Colorretais/genética , Metilação de DNA , Regulação Neoplásica da Expressão Gênica , Genes Supressores de Tumor , Genes myc , Complexo Repressor Polycomb 2/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Transição Epitelial-Mesenquimal/genética , Humanos , Modelos Biológicos , Proteínas de Neoplasias , Interferência de RNA , Fatores de Transcrição
11.
Sci Rep ; 7(1): 9911, 2017 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-28855625

RESUMO

This study aimed to determine whether a serological response could predict the normalization of cerebrospinal fluid (CSF) abnormalities at 6 months after treatment in human immunodeficiency virus (HIV)-negative neurosyphilis patients. A total of 123 neurosyphilis patients were recruited at baseline, 58 of these patients undergoing treatment, repeated CSF examinations and serological tests for syphilis at 6 months after treatment were included in the follow-up study. Before treatment, the CSF rapid plasma reagin (RPR) titer, CSF Treponema pallidum particle agglutination (TPPA) titer, CSF leukocyte count, and CSF protein concentration were correlated with both serum RPR and TPPA titers. At 6 months after treatment, 28 and nine patients achieved serological responses of RPR and TPPA tests, respectively. The sensitivities of the serological response of RPR and TPPA tests for identifying the normalization of CSF abnormalities were 60.0∼83.3% and 17.1~22.2%, respectively; and 75.0∼91.3% of patients showing serological response of RPR test also achieved CSF normalization, suggesting that the serological response could predict CSF normalization to some degree. Particularly, in patients with ≥8-fold decreases in the serum RPR titer, the CSF RPR, CSF leukocyte count, and CSF protein concentration had normalized, and follow-up lumbar puncture could be reduced considering the resolution of neurological symptoms.


Assuntos
Neurossífilis/sangue , Neurossífilis/líquido cefalorraquidiano , Penicilinas/uso terapêutico , Treponema pallidum/efeitos dos fármacos , Adulto , Antibacterianos/uso terapêutico , Ceftriaxona/uso terapêutico , Doxiciclina/uso terapêutico , Feminino , Humanos , Corpos de Inclusão/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Neurossífilis/tratamento farmacológico , Testes Sorológicos/métodos , Sorodiagnóstico da Sífilis/métodos , Fatores de Tempo , Resultado do Tratamento , Treponema pallidum/fisiologia
12.
Clin Chim Acta ; 464: 136-141, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27876463

RESUMO

BACKGROUND: The rabbit infectivity test (RIT) was previously described as a highly-sensitive method for clinically detecting Treponema pallidum. But our primary study indicated this result may have changed in current antibiotics era. METHODS: By inoculating rabbits testis with cerebrospinal fluid (CSF) (n=63) and exudate from hard chancre lesions (n=13), we re-evaluated the sensitivity of RIT in modern era. All isolated T. pallidum strains from the RIT were performed for the strain type based on "CDC subtype/tp0548" method. Chi-square and Fisher's exact tests were used to determine the statistical significance of differences across data sets. RESULTS: Result indicated that 2 of 63 CSF (2/63, 3.17%) and 5 of 13 lesion exudate samples (5/13, 38.47%) were positive in the RIT, with a much longer time to detection for CSF samples. Only 1 of 28 samples from patients who admitted treatment with antibiotics prior to clinical exam was positive in the RIT; while 6 of 48 patients, who admitted no recent exposure to antibiotics or was unclear about the medical history, were positive in RIT. DNA sequence analysis revealed 6 strains of 14d/f subtype and one strain of 14a/f subtype. CONCLUSIONS: In conclusions, RIT is no longer a highly sensitive method for detecting T. pallidum in clinical samples as before, and is not inadequately considered to be a reference method for measuring the sensitivity of other new methods, such as the PCR. These data represent the first reexamination of the sensitivity of RIT in the post-antibiotic era with a large clinical sample.


Assuntos
Técnicas de Laboratório Clínico/métodos , Treponema pallidum/patogenicidade , Adulto , Idoso , Animais , Feminino , Humanos , Limite de Detecção , Masculino , Pessoa de Meia-Idade , Tipagem Molecular , Neurossífilis/microbiologia , Coelhos , Treponema pallidum/classificação , Treponema pallidum/isolamento & purificação , Adulto Jovem
13.
Clin Chim Acta ; 463: 103-108, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27751728

RESUMO

BACKGROUND: Neurosyphilis (NS) is difficult to diagnose, especially in syphilis patients with negative cerebrospinal fluid (CSF) rapid plasma reagin (RPR) or Venereal Disease Research Laboratory (VDRL) tests. METHODS: We conducted a cross-sectional study and an analysis of macrophage migration inhibitory factor (MIF) in syphilitic patients to identify a novel marker for the diagnosis of NS, with a focus on probable NS (NS with negative VDRL/RPR tests). For this purpose, CSF and serum MIF concentrations were determined in 43 NS and 43 syphilis/non-NS (N-NS) patients at the Zhongshan Hospital of the Medical College of Xiamen University from July 2014 to June 2015. Sixty-three blood donors were used as healthy controls. RESULTS: NS patients had higher CSF (median [IQR]: 8.77ng/ml [4.76-19.13]) and serum (52.58ng/ml [28.31-95.94]) MIF concentrations than N-NS patients did (4.08 [2.21-9.68] and 34.30 [19.77-59.75], respectively). Using a cut-off point of 6.63ng/ml, CSF MIF had a sensitivity of 74.42% and a specificity of 67.74% for the diagnosis of NS. The sensitivity was higher than that of CSF RPR (39.53%) and increased protein (48.84%) tests and similar to that of CSF pleocytosis (67.44%). Additionally, the sensitivity of CSF MIF, which was 92.31% for the diagnosis of probable NS, was higher than that of CSF pleocytosis (65.38%) and increased protein (53.85%) tests. By integrating all CSF parameters (pleocytosis, increased protein and MIF), the sensitivity would be improved to 100% by parallel testing, which would avoid missed diagnoses. Moreover, the specificity would be improved to 100% by the serial testing algorithm, which would again avoid misdiagnosis. CONCLUSIONS: CSF MIF concentrations can be used as a novel CSF marker to establish or exclude a diagnosis of NS.


Assuntos
Soronegatividade para HIV , Fatores Inibidores da Migração de Macrófagos/líquido cefalorraquidiano , Neurossífilis/líquido cefalorraquidiano , Neurossífilis/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/líquido cefalorraquidiano , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
14.
PLoS One ; 8(8): e69553, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23940523

RESUMO

INTRODUCTION: X-ray repair cross-complementing protein 3 (XRCC3) is an essential gene involved in the double-strand break repair pathway. Published evidence has shown controversial results about the relationship between XRCC3 Thr241Met polymorphism and clinical outcomes of non-small cell lung cancer (NSCLC) patients receiving platinum-based chemotherapy. METHODS: A systematic review and meta-analysis was performed to evaluate the predictive value of XRCC3 Thr241Met polymorphism on clinical outcomes of advanced NSCLC receiving platinum-based chemotherapy. Response to chemotherapy, overall survival (OS) and progression-free survival (PFS) were analyzed. RESULTS: A number of 11 eligible studies were identified according to the inclusion criteria. Carriers of the variant XRCC3 241Met allele were significantly associated with good response to platinum-based chemotherapy (ThrMet/MetMet vs. ThrThr: OR  = 1.509, 95% CI: 1.099-2.072, Pheterogeneity  = 0.618). The XRCC3 Thr241Met polymorphism was not associated with OS (MetMet vs. ThrThr, HR  = 0.939, 95% CI:0.651-1.356, Pheterogeneity  = 0.112) or PFS (MetMet vs. ThrThr, HR  = 0.960, 95% CI: 0.539-1.710, Pheterogeneity  = 0.198). Additionally, no evidence of publication bias was observed. CONCLUSIONS: This systematic review and meta-analysis shows that carriers of the XRCC3 241Met allele are associated with good response to platinum-based chemotherapy in advanced NSCLC, while the XRCC3 Thr241Met polymorphism is not associated with OS or PFS.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Proteínas de Ligação a DNA/genética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Platina/uso terapêutico , Polimorfismo Genético/genética , Alelos , Humanos , Resultado do Tratamento
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