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1.
J Am Chem Soc ; 145(30): 16726-16738, 2023 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-37486968

RESUMO

Peptide hormones are essential signaling molecules with therapeutic importance. Identifying regulatory factors that drive their activity gives important insight into their mode of action and clinical development. In this work, we demonstrate the combined impact of Cu(II) and the serum protein albumin on the activity of C-peptide, a 31-mer peptide derived from the same prohormone as insulin. C-peptide exhibits beneficial effects, particularly in diabetic patients, but its clinical use has been hampered by a lack of mechanistic understanding. We show that Cu(II) mediates the formation of ternary complexes between albumin and C-peptide and that the resulting species depend on the order of addition. These ternary complexes notably alter peptide activity, showing differences from the peptide or Cu(II)/peptide complexes alone in redox protection as well as in cellular internalization of the peptide. In standard clinical immunoassays for measuring C-peptide levels, the complexes inflate the quantitation of the peptide, suggesting that such adducts may affect biomarker quantitation. Altogether, our work points to the potential relevance of Cu(II)-linked C-peptide/albumin complexes in the peptide's mechanism of action and application as a biomarker.


Assuntos
Cobre , Albumina Sérica , Humanos , Albumina Sérica/metabolismo , Cobre/química , Peptídeo C , Peptídeos/metabolismo , Oxirredução
2.
Abdom Radiol (NY) ; 48(2): 704-712, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36464756

RESUMO

OBJECTIVES: To compare the diagnostic performance for the detection of clinically significant prostate cancer (csPCa) between bpMRI with only axial T2WI (simplified bpMRI) and standard-multiparametric MRI (mpMRI). METHODS: A total of 569 patients who underwent mpMRI followed by biopsy or prostatectomy were enrolled in this retrospective study. According to PI-RADS v2.1, three radiologists (A, B, C) from three centers blinded to clinical variables were assigned scores on lesions with simplified bpMRI and then with mpMRI 2 weeks later. Diagnostic performance of simplified bpMRI was compared with mpMRI using histopathology as reference standard. RESULTS: For all the three radiologists, the diagnostic sensitivity was significantly higher with mpMRI than with simplified bpMRI (P < 0.001 to P = 0.035); and although specificity was also higher with mpMRI than with simplified bpMRI for radiologist B and radiologist C, it was statistically significant only for radiologist B (P = 0.011, P = 0.359, respectively). On the contrary, for radiologist A, specificity was higher with simplified bpMRI than with mpMRI (P = 0.001). The area under the receiver operating characteristic curve (AUC) was significantly higher for mpMRI than for simplified bpMRI except for radiologist A (radiologist A: 0.903 vs 0.913, P = 0.1542; radiologist B: 0.861 vs 0.834 P = 0.0013; and radiologist C: 0.884 vs 0.848, P = 0.0003). Interobserver reliability of PI-RADS v2.1 showed good agreement for both simplified bpMRI (kappa = 0.665) and mpMRI (kappa = 0.739). CONCLUSION: Although the detection of csPCa with simplified bpMRI was comparatively lower than that with mpMRI, the diagnostic performance was still high in simplified bpMRI. Our data justify using mpMRI outperforms simplified bpMRI for prostate cancer screening and imply simplified bpMRI as a potential screening tool.


Assuntos
Imageamento por Ressonância Magnética Multiparamétrica , Neoplasias da Próstata , Masculino , Humanos , Neoplasias da Próstata/patologia , Imageamento por Ressonância Magnética , Estudos Retrospectivos , Detecção Precoce de Câncer , Reprodutibilidade dos Testes , Antígeno Prostático Específico
3.
J Neurosci ; 42(25): 5102-5114, 2022 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-35606145

RESUMO

Increasing loss of structure and function of neurons and decline in cognitive function is commonly seen during the progression of neurologic diseases, although the causes and initial symptoms of individual diseases are distinct. This observation suggests a convergence of common degenerative features. In myotonic dystrophy type 1 (DM1), the expression of expanded CUG RNA induces neurotransmission dysfunction before axon and dendrite degeneration and reduced MBNL2 expression associated with aberrant alternative splicing. The role of loss of function of MBNL2 in the pathogenesis of neurodegeneration and the causal mechanism of neurodegeneration-reduced expression of MBNL2 remain elusive. Here, we show that increased MBNL2 expression is associated with neuronal maturation and required for neuronal morphogenesis and the fetal to adult developmental transition of RNA processing. Neurodegenerative conditions including NMDA receptor (NMDAR)-mediated excitotoxicity and dysregulated calcium homeostasis triggered nuclear translocation of calpain-2, thus resulting in MBNL2 degradation and reversal of MBNL2-regulated RNA processing to developmental patterns. Nuclear expression of calpain-2 resembled its developmental pattern and was associated with MBNL2 degradation. Knock-down of calpain-2 expression or inhibition of calpain-2 nuclear translocation prevented neurodegeneration-reduced MBNL2 expression and dysregulated RNA processing. Increased calpain-2 nuclear translocation associated with reduced MBNL2 expression and aberrant RNA processing occurred in models for DM1 and Alzheimer's disease (AD) including EpA960/CaMKII-Cre mice of either sex and female APP/PS1 and THY-Tau22 mice. Our results identify a regulatory mechanism for MBNL2 downregulation and suggest that calpain-2-mediated MBNL2 degradation accompanied by re-induction of a developmental RNA processing program may be a converging pathway to neurodegeneration.SIGNIFICANCE STATEMENT Neurologic diseases share many features during disease progression, such as cognitive decline and brain atrophy, which suggests a common pathway for developing degenerative features. Here, we show that the neurodegenerative conditions glutamate-induced excitotoxicity and dysregulated calcium homeostasis induced translocation of the cysteine protease calpain-2 into the nucleus, resulting in MBNL2 degradation and reversal of MBNL2-regulated RNA processing to an embryonic pattern. Knock-down or inhibition of nuclear translocation of calpain-2 prevented MBNL2 degradation and maintained MBNL2-regulated RNA processing in the adult pattern. Models of myotonic dystrophy and Alzheimer's disease (AD) also showed calpain-2-mediated MBNL2 degradation and a developmental RNA processing program. Our studies suggest MBNL2 function disrupted by calpain-2 as a common pathway, thus providing an alternative therapeutic strategy for neurodegeneration.


Assuntos
Doença de Alzheimer , Calpaína/metabolismo , Distrofia Miotônica , Processamento Alternativo , Animais , Cálcio/metabolismo , Feminino , Camundongos , Distrofia Miotônica/genética , Distrofia Miotônica/patologia , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo
4.
Thorac Cancer ; 13(9): 1322-1332, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35373505

RESUMO

BACKGROUND: Programmed death ligand-1 (PD-L1) has a known association with the prognosis of human cancers because of its ability to alter tumor immune surveillance via its interaction with PD-1. We questioned whether expression of PD-L1 in tumor cells could directly promote tumor growth and invasiveness in non-small cell lung cancer (NSCLC). METHODS: Real-time reverse transcription-polymerase chain reaction (RT-PCR) was performed to evaluate PD-L1 messenger RNA (mRNA) expression in lung tumors. The prognostic value of PD-L1 mRNA was assessed by Cox regression model. Transcriptional regulation of PD-L1 by human papillomavirus (HPV) 16/18 E6 oncoprotein or by epidermal growth factor receptor (EGFR) mutation in lung cancer cells was examined by Western blot and luciferase reporter assay. The cell growth and invasion were evaluated by colony formation, soft agar growth, and Boyden chamber assay. RESULTS: The PD-L1 mRNA levels showed a positive association with HPV 16/18 E6 oncoprotein and with EGFR mutation in 223 surgically resected NSCLC patients. The prognostic significance of PD-L1 was more commonly observed in patients with high PD-L1/E6 positive and high PD-L1/EGFR mutant tumors. Mechanistically, upregulation of PD-L1 transcription by E6 or mutant EGFR occurred largely through the ERK-C/EBPß-TLR4-NF-κB cascade. PD-L1 promotes the efficacy of colony formation, soft agar growth, and cell invasion. PD-L1 upregulates BAG-1 to reduce transforming growth factor (TGF)-ß1 expression, and the decrease in SMAD4 because of TGF-ß1 occurs through the p53/microRNA (miR)-224 axis. The decreases in TGF-ß1 and SMAD4 are responsible for PD-L1-mediated cell invasiveness. CONCLUSION: Induction of PD-L1 by E6 oncoprotein or mutant EGFR through the ERK-C/EBPß-TLR4-NF-κB cascade may promote tumor growth and invasiveness in NSCLC because of decreasing TGF-ß1 and SMAD4 expression.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Ágar , Antígeno B7-H1/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Receptores ErbB/genética , Regulação Neoplásica da Expressão Gênica , Papillomavirus Humano 16/metabolismo , Papillomavirus Humano 18/genética , Papillomavirus Humano 18/metabolismo , Humanos , Neoplasias Pulmonares/patologia , NF-kappa B/genética , RNA Mensageiro , Proteína Smad4/genética , Proteína Smad4/metabolismo , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/metabolismo
5.
ACS Bio Med Chem Au ; 2(1): 11-21, 2022 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-35187536

RESUMO

Radical S-adenosylmethionine (radical SAM or rSAM) enzymes use their S-adenosylmethionine cofactor bound to a unique Fe of a [4Fe-4S] cluster to generate the "hot" 5'-deoxyadenosyl radical, which drives highly selective radical reactions via specific interactions with a given rSAM enzyme's substrate. This Perspective focuses on the two rSAM enzymes involved in the biosynthesis of the organometallic H-cluster of [FeFe] hydrogenases. We present here a detailed sequential model initiated by HydG, which lyses a tyrosine substrate via a 5'-deoxyadenosyl H atom abstraction from those amino acid's amino group, initially producing dehydroglycine and an oxidobenzyl radical. In this model, two successive radical cascade reactions lead ultimately to the formation of HydG's product, a mononuclear Fe organometallic complex: [Fe(II)(CN)(CO)2(cysteinate)]-, with the iron originating from a unique "dangler" Fe coordinated by a cysteine ligand providing a sulfur bridge to another [4Fe-4S] auxiliary cluster in the enzyme. In turn, in this model, [Fe(II)(CN)(CO)2(cysteinate)]- is the substrate for HydE, the second rSAM enzyme in the biosynthetic pathway, which activates this mononuclear organometallic unit for dimerization, forming a [Fe2S2(CO)4(CN)2] precursor to the [2Fe] H component of the H-cluster, requiring only the completion of the bridging azadithiolate (SCH2NHCH2S) ligand. This model is built upon a foundation of data that incorporates cell-free synthesis, isotope sensitive spectroscopies, and the selective use of synthetic complexes substituting for intermediates in the enzymatic "assembly line". We discuss controversies pertaining to this model and some remaining open issues to be addressed by future work.

6.
Biochemistry ; 61(2): 107-116, 2022 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-34989236

RESUMO

The radical S-adenosyl-l-methionine (SAM) enzyme HydG cleaves tyrosine to generate CO and CN- ligands of the [FeFe] hydrogenase H-cluster, accompanied by the formation of a 4-oxidobenzyl radical (4-OB•), which is the precursor to the HydG p-cresol byproduct. Native HydG only generates a small amount of 4-OB•, limiting detailed electron paramagnetic resonance (EPR) spectral characterization beyond our initial EPR lineshape study employing various tyrosine isotopologues. Here, we show that the concentration of trapped 4-OB• is significantly increased in reactions using HydG variants, in which the "dangler Fe" to which CO and CN- bind is missing or substituted by a redox-inert Zn2+ ion. This allows for the detailed characterization of 4-OB• using high-field EPR and electron nuclear double resonance spectroscopy to extract its g-values and 1H/13C hyperfine couplings. These results are compared to density functional theory-predicted values of several 4-OB• models with different sizes and protonation states, with a best fit to the deprotonated radical anion configuration of 4-OB•. Overall, our results depict a clearer electronic structure of the transient 4-OB• radical and provide new insights into the radical SAM chemistry of HydG.


Assuntos
Proteínas de Bactérias , Proteínas Ferro-Enxofre , S-Adenosilmetionina , Shewanella , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Espectroscopia de Ressonância de Spin Eletrônica , Radicais Livres/química , Radicais Livres/metabolismo , Proteínas Ferro-Enxofre/química , Proteínas Ferro-Enxofre/metabolismo , Modelos Moleculares , S-Adenosilmetionina/química , S-Adenosilmetionina/metabolismo , Shewanella/química , Shewanella/metabolismo
7.
Biochemistry ; 60(40): 3016-3026, 2021 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-34569243

RESUMO

The [FeFe] hydrogenase catalyzes the redox interconversion of protons and H2 with a Fe-S "H-cluster" employing CO, CN, and azadithiolate ligands to two Fe centers. The biosynthesis of the H-cluster is a highly interesting reaction carried out by a set of Fe-S maturase enzymes called HydE, HydF, and HydG. HydG, a member of the radical S-adenosylmethionine (rSAM) family, converts tyrosine, cysteine, and Fe(II) into an organometallic Fe(II)(CO)2(CN)cysteine "synthon", which serves as the substrate for HydE. Although key aspects of the HydG mechanism have been experimentally determined via isotope-sensitive spectroscopic methods, other important mechanistic questions have eluded experimental determination. Here, we use computational quantum chemistry to refine the mechanism of the HydG catalytic reaction. We utilize quantum mechanics/molecular mechanics simulations to investigate the reactions at the canonical Fe-S cluster, where a radical cleavage of the tyrosine substrate takes place and proceeds through a relay of radical intermediates to form HCN and a COO•- radical anion. We then carry out a broken-symmetry density functional theory study of the reactions at the unusual five-iron auxiliary Fe-S cluster, where two equivalents of CN- and COOH• coordinate to the fifth "dangler iron" in a series of substitution and redox reactions that yield the synthon as the final product for further processing by HydE.


Assuntos
Proteínas de Bactérias/química , Complexos de Coordenação/química , Cisteína/química , Hidrogenase/química , Proteínas Ferro-Enxofre/química , Biocatálise , Ferro/química , Ligantes , Modelos Químicos , Teoria Quântica , Thermoanaerobacter/enzimologia , Tirosina/química
8.
Diabetes Metab Syndr Obes ; 14: 2381-2388, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34079316

RESUMO

PURPOSE: Peripheral vascular disease (PVD) is a life-threatening condition affecting the lower extremities. Common risk factors include type 2 diabetes (T2D), hypertension, dyslipidemia, smoking, and older age. There is a little-documented research on the genetic basis of the disease in Taiwan. We examined the impact of T2D and the blood pressure-associated rs17367504 variant of the Methylenetetrahydrofolate reductase (MTHFR) gene on PVD risk. MATERIALS AND METHODS: In this population-based association study, we linked data from 8992 participants in Taiwan Biobank (TWB) to their medical records in the National Health Insurance Research Database (NHIRD). Participants were 30 to 70 years old at recruitment and included those assessed between 2008 and 2015. We tested for association of PVD with rs17367504 and T2D using multiple logistic regression models. The rs17367504 variant was assessed using the Axiom-Taiwan Biobank Array Plate (TWB chip: Affymetrix, Inc., Santa Clara, CA, USA). RESULTS: Among cases with T2D (n = 1294), 158 (12.21%) were identified with PVD. T2D was associated with PVD (odds ratio [OR], 1.52; 95% confidence interval [CI], 1.21-1.91; p<0.001) whereas rs17367504 variant was not (OR, 0.96; CI, 0.76-1.21; p = 0.728 in AG/GG compared to AA homozygotes). However, T2D and rs17367504 had an interactive effect on PVD (p for interaction = 0.0076). Results from our stratified analyses displayed OR of 1.75 (CI, 1.35-2.26; p<0.001) in AA individuals with DM and 0.94 (CI, 0.56-1.58; p = 0.811) in AG+GG individuals with T2D. Using the AA genotype and no T2D as the reference group, the respective OR of PVD was 1.77 (CI, 1.38-2.28; p<0.001) in AA individuals with T2D; 1.18 (CI, 0.91-1.55; p = 0.215) in AG+GG individuals with no T2D, and 1.03 (CI, 0.66-1.60; p = 0.892) in AG+GG individuals with T2D . CONCLUSION: We found that type 2 diabetes was associated with increased risk of peripheral vascular disease, particularly in AA genotype carriers of the rs17367504 variant in Taiwan.

9.
Nat Neurosci ; 24(6): 799-809, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33958802

RESUMO

The most significant common variant association for schizophrenia (SCZ) reflects increased expression of the complement component 4A (C4A). Yet, it remains unclear how C4A interacts with other SCZ risk genes or whether the complement system more broadly is implicated in SCZ pathogenesis. Here, we integrate several existing, large-scale genetic and transcriptomic datasets to interrogate the functional role of the complement system and C4A in the human brain. Unexpectedly, we find no significant genetic enrichment among known complement system genes for SCZ. Conversely, brain co-expression network analyses using C4A as a seed gene reveal that genes downregulated when C4A expression increases exhibit strong and specific genetic enrichment for SCZ risk. This convergent genomic signal reflects synaptic processes, is sexually dimorphic and most prominent in frontal cortical brain regions, and is accentuated by smoking. Overall, these results indicate that synaptic pathways-rather than the complement system-are the driving force conferring SCZ risk.


Assuntos
Encéfalo/patologia , Redes Reguladoras de Genes/genética , Predisposição Genética para Doença/genética , Esquizofrenia/genética , Esquizofrenia/patologia , Sinapses/patologia , Bases de Dados Genéticas , Feminino , Expressão Gênica , Estudo de Associação Genômica Ampla/métodos , Humanos , Masculino , Estudos Retrospectivos , Transdução de Sinais/genética
10.
FASEB J ; 35(5): e21512, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33811692

RESUMO

Vascular rarefaction due to impaired angiogenesis is associated with contractile dysfunction and the transition from compensation to decompensation and heart failure. The regulatory mechanism controlling vascular rarefaction during the transition remains elusive. Increased expression of a nuclear RNA-binding protein CUGBP Elav-like family member 1 (CELF1) in the adult heart is associated with the transition from compensated hypertrophy to decompensated heart failure. Elevated CELF1 level resulted in degradation of the major cardiac gap junction protein, connexin 43, in dilated cardiomyopathy (DCM), the most common cause of heart failure. In the present study, we investigated the role of increased CELF1 expression in causing vascular rarefaction in DCM. CELF1 overexpression (CELF1-OE) in cardiomyocytes resulted in reduced capillary density. CELF1-OE mice administered hypoxyprobe showed immunoreactivity and increased mRNA levels of HIF1α, Glut-1, and Pdk-1, which suggested the association of a reduced capillary density-induced hypoxic condition with CELF1 overexpression. Vegfa mRNA level was downregulated in mouse hearts exhibiting DCM, including CELF1-OE and infarcted hearts. Vegfa mRNA level was also downregulated to a similar extent in cardiomyocytes isolated from infarcted hearts by Langendorff preparation, which suggested cardiomyocyte-derived Vegfa expression mediated by CELF1. Cardiomyocyte-specific depletion of CELF1 preserved the capillary density and Vegfa mRNA level in infarcted mouse hearts. Also, CELF1 bound to Vegfa mRNA and regulated Vegfa mRNA stability via the 3' untranslated region. These results suggest that elevated CELF1 level has dual effects on impairing the functions of cardiomyocytes and microvasculature in DCM.


Assuntos
Proteínas CELF1/metabolismo , Insuficiência Cardíaca/patologia , Microvasos/patologia , Proteólise , Estabilidade de RNA , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Proteínas CELF1/genética , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microvasos/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética
11.
ACS Chem Biol ; 16(10): 1951-1960, 2021 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-33769035

RESUMO

O-Acetylation is a common naturally occurring modification of carbohydrates and is especially widespread in sialic acids, a family of nine-carbon acidic monosaccharides. O-Acetyl migration within the exocyclic glycerol-like side chain of mono-O-acetylated sialic acid reported previously was from the C7- to C9-hydroxyl group with or without an 8-O-acetyl intermediate, which resulted in an equilibrium that favors the formation of the 9-O-acetyl sialic acid. Herein, we provide direct experimental evidence demonstrating that O-acetyl migration is bidirectional, and the rate of equilibration is influenced predominantly by the pH of the sample. While the O-acetyl group on sialic acids and sialoglycans is stable under mildly acidic conditions (pH < 5, the rate of O-acetyl migration is extremely low), reversible O-acetyl migration is observed readily at neutral pH and becomes more significant when the pH increases to slightly basic. Sialoglycan microarray studies showed that esterase-inactivated porcine torovirus hemagglutinin-esterase bound strongly to sialoglycans containing a more stable 9-N-acetylated sialic acid analog, but these compounds were less resistant to periodate oxidation treatment compared to their 9-O-acetyl counterparts. Together with prior studies, the results support the possible influence of sialic acid O-acetylation and O-acetyl migration to host-microbe interactions and potential application of the more stable synthetic N-acetyl mimics.


Assuntos
Hemaglutininas Virais/metabolismo , Polissacarídeos/metabolismo , Ácidos Siálicos/metabolismo , Proteínas Virais de Fusão/metabolismo , Acetilação , Animais , Bovinos , Cromatografia Líquida de Alta Pressão , Hemaglutininas Virais/química , Estrutura Molecular , Oxirredução , Ácido Periódico/química , Fenilenodiaminas/química , Polissacarídeos/análise , Polissacarídeos/química , Ligação Proteica , Ácidos Siálicos/análise , Ácidos Siálicos/química , Torovirus/enzimologia , Proteínas Virais de Fusão/química
12.
Thorac Cancer ; 12(4): 534-538, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33372419

RESUMO

BACKGROUND: The human 8-oxoguanine DNA glycosylase 1 (hOGG1) gene encodes a DNA glycosylase that removes 8-hydroxy-2-deoxyguanine (8-OH-dG) DNA damage to protect against gene mutations. The association of hOGG1 Ser326Cys polymorphism with lung cancer risk has predicted that hOGG1-Cys variants are less effective at removing 8-OH-dG damage from DNA; therefore, these variants might show an increased occurrence of tumor suppressor gene and oncogene mutations. However, no evidence has yet supported this hypothesis. METHODS: Direct sequencing was performed to examine the mutations of p53 and EGFR genes in lung tumors from patients with non-small cell lung cancer (NSCLC). Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to examine hOGG1 Ser326Cys polymorphism in this study population. RESULTS: A total of 99 p53-mutated and 99 EGFR-mutated patients with NSCLC were selected to explore the possible associations of these mutations with hOGG1 Ser326Cys polymorphism. The p53-mutated and EGFR-mutated patients were divided into nondeletion and deletion subgroups. P53 deletion mutations were more commonly observed in male than in female patients (P = 0.030). However, EGFR exon 19 deletion mutations were more prevalent in female and adenocarcinoma patients than in male and squamous cell carcinoma patients (P = 0.028 for genders, P = 0.017 for tumor histology). Interestingly, p53 and EGFR exon 19 deletion mutations were more frequent in patients with hOGG1 Ser/Cys + Cys/Cys hOGG1-Cys variants than with the hOGG1 Ser/Ser genotype (P = 0.010 for p53, P = 0.032 for EGFR). CONCLUSIONS: We suggest that the association of hOGG1 Ser326Cys polymorphism with lung cancer risk could be partially explained by increases in p53 and EGFR deletion mutations. KEY POINTS: SIGNIFICANT FINDINGS OF THE STUDY: NSCLC patients with hOGG1-Cys variants may have a higher risk of p53 and EGFR deletion mutations than with hOGG1 Ser/Ser genotype. WHAT THIS STUDY ADDS: NSCLC patients with hOGG1-Cys variants might be helpful to predict patients having higher risk of EGFR exon 19 deletion mutations and these patients who were treated with gefitinib or erlotinib could be a higher risk to occur EGFR T790M mutation.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , DNA Glicosilases/genética , Neoplasias Pulmonares/genética , Proteína Supressora de Tumor p53/genética , Idoso , Carcinoma Pulmonar de Células não Pequenas/metabolismo , DNA Glicosilases/metabolismo , Receptores ErbB/genética , Receptores ErbB/metabolismo , Feminino , Predisposição Genética para Doença , Variação Genética , Humanos , Neoplasias Pulmonares/metabolismo , Masculino , Mutação , Proteína Supressora de Tumor p53/metabolismo
13.
Am J Cancer Res ; 10(4): 1229-1237, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32368398

RESUMO

NKX2-1 was shown to enhance cisplatin sensitivity in KRAS-mutated cells, but it conferred cisplatin resistance in EGFR-mutated lung adenocarcinoma cells. However, NKX2-1 as a dual role in tumor progression depended on p53 mutational status via modulation of the NF-κB pathway. We hypothesized that NKX2-1 may confer cisplatin resistance in p53-mutated (p53-MT) lung adenocarcinoma cells but may enhance cisplatin sensitivity in wild-type (p53-WT) cells. In the present study, six p53-MT and -p53-WT cell lines were treated with various concentrations of cisplatin to calculate the inhibitory concentration of cisplatin for 50% cell viability (IC50). The IC50 value was positively correlated with NKX2-1 expression in the p53-MT cells but negatively correlated in the p53-WT cells. TNFSF10 was identified in a microarray analysis as a potential candidate responsible for NKX2-1-mediated apoptosis induced by cisplatin. The retrospective study evaluated 97 surgically resected lung adenocarcinoma patients receiving cisplatin-based chemotherapy to explore the possible association between NKX2-1 expression and tumor response. Patients with higher TNFSF10 mRNA levels, as determined by real-time reverse transcription-polymerase Chain Reaction (RT-PCR), typically showed an favorable response when compared with patients with lower TNFSF10 mRNA levels. Additionally, the association of higher TNFSF10 mRNA levels with favorable response was only revealed in p53-WT patients, not in p53-MT patients. Higher NKX2-1 mRNA levels were associated with an unfavorable response in patients with p53-MT tumors but a favorable response in patients with p53-WT tumors. In summary, modulation of TNFSF10 expression by NKX2-1 may be a potential indicator for predicting the response to cisplatin-based chemotherapy in patients with lung adenocarcinomas.

14.
Thorac Cancer ; 11(7): 1904-1910, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32394538

RESUMO

BACKGROUND: Several studies have previously indicated that nuclear factor erythroid 2-related factor 2 (Nrf2) expression may promote tumor progression when the Keap1/Nrf2 pathway is activated, but few reports have demonstrated the role of cytoplasmic Nrf2 on tumorigenesis. METHODS: Immunohistochemistry was conducted to evaluate Nrf2 expression in 167 tumors from surgically-resected patients with non-small cell lung cancer (NSCLC). Univariate and multivariate analyses were performed to examine the association of Nrf2 expression with patients' prognosis. This study was conducted to examine the association of Nrf2 expression with tumor response to cisplatin-based chemotherapy. RESULTS: Among these tumors, 56 and 32 of 167 tumors expressed Nrf2 in the cytoplasm (34% for C+/N-) and in the cytoplasm/nucleus (19% for C+/N+), but not in the nucleus of tumor cells. Nrf2 was negatively expressed in the remainder of the tumor samples (C-/N-, 79 of 167, 47%). Univariate analysis indicated that patients with Nrf2 positive tumors (C+/N- plus C+/N+) had worse overall survival (OS), but not relapse-free survival (RFS) than with Nrf2 negative tumors (C-/N-). However, patients with C+/N- tumors possessed worse OS and RFS than those with Nrf2 negative tumors (C-/N-). Multivariate analysis further confirmed the prognostic significance of patients with Nrf2 positive and C+/N- tumors on OS and RFS, but not on RFS for patients with Nrf2 positive tumors. Patients with Nrf2 positive and C+/N- tumors were determined to more frequently have an unfavorable response to cisplatin-based chemotherapy than those with Nrf2 negative tumors. CONCLUSIONS: Cytoplasmic Nrf2 expression might potentially be used to predict poor prognosis and unfavorable response to cisplatin-based chemotherapy in patients with NSCLC. KEY POINTS: The expression of cytoplasmic Nrf2 showed a significant relationship with patients' response to cisplatin-based chemotherapy and influenced NSCLC prognosis. A proteasomal inhibitor such as carfilzomib might be used to improve the outcomes and therapeutic response to cisplatin-based chemotherapy in patients with tumors showing cytoplasmic Nrf2 expression.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/mortalidade , Núcleo Celular/metabolismo , Cisplatino/uso terapêutico , Citoplasma/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Recidiva Local de Neoplasia/mortalidade , Idoso , Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/metabolismo , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Masculino , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/metabolismo , Recidiva Local de Neoplasia/patologia , Prognóstico , Taxa de Sobrevida
15.
Cancers (Basel) ; 12(2)2020 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-32098209

RESUMO

Increased ventilation during exercise in polluted areas could trigger airway inflammation. We evaluated blood DNA methylation of the SOX2-promoter region in relation to exercise and PM2.5 in Taiwanese adults. Data of 948 participants aged 30-70 years were retrieved from the Taiwan Biobank Database (2008-2015) and the Air Quality Monitoring Database (2006-2011). PM2.5 was positively associated with SOX2-promoter methylation (ß = 0.000216; p < 0.0001). The interaction between PM2.5 and exercise on SOX2-promoter methylation was significant (p = 0.0146). After stratification by exercise habits, PM2.5 was positively associated with SOX2 methylation in only individuals who did regular exercise (ß = 0.0003490; p < 0.0001). After stratification by exercise habits and residential areas, SOX2-promoter methylation levels in those who lived in the southern area were higher for both the regular exercise (ß = 0.00272; p = 0.0172) and no regular exercise groups (ß = 0.002610 and p = 0.0162). SOX2-promoter methylation levels in those who lived in the northern area and did regular exercise were lower; ß = -0.00314 (p = 0.0036). In conclusion, PM2.5 was positively associated with SOX2-promoter methylation in participants who did regular exercise. Living in the southern area was positively associated with SOX2-promoter methylation regardless of exercise habits.

16.
J Chem Theory Comput ; 16(2): 1115-1127, 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-31917572

RESUMO

Molecular dynamics simulations are helpful tools for a range of applications, ranging from drug discovery to protein structure determination. The successful use of this technology largely depends on the potential function, or force field, used to determine the potential energy at each configuration of the system. Most force fields encode all of the relevant parameters to be used in distinct atom types, each associated with parameters for all parts of the force field, typically bond stretches, angle bends, torsions, and nonbonded terms accounting for van der Waals and electrostatic interactions. Much attention has been paid to the nonbonded parameters and their derivation, which are important in particular due to their governance of noncovalent interactions, such as protein-ligand binding. Parametrization involves adjusting the nonbonded parameters to minimize the error between simulation results and experimental properties, such as heats of vaporization and densities of neat liquids. In this setting, determining the best set of atom types is far from trivial, and the large number of parameters to be fit for the atom types in a typical force field can make it difficult to approach a true optimum. Here, we utilize a previously described Minimal Basis Iterative Stockholder (MBIS) method to carry out an atoms-in-molecules partitioning of electron densities. Information from these atomic densities is then mapped to Lennard-Jones parameters using a set of mapping parameters much smaller than the typical number of atom types in a force field. This approach is advantageous in two ways: it eliminates atom types by allowing each atom to have unique Lennard-Jones parameters, and it greatly reduces the number of parameters to be optimized. We show that this approach yields results comparable to those obtained with the typed GAFF 1.7 force field, even when trained on a relatively small amount of experimental data.

17.
Cell ; 178(4): 850-866.e26, 2019 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-31398340

RESUMO

We performed a comprehensive assessment of rare inherited variation in autism spectrum disorder (ASD) by analyzing whole-genome sequences of 2,308 individuals from families with multiple affected children. We implicate 69 genes in ASD risk, including 24 passing genome-wide Bonferroni correction and 16 new ASD risk genes, most supported by rare inherited variants, a substantial extension of previous findings. Biological pathways enriched for genes harboring inherited variants represent cytoskeletal organization and ion transport, which are distinct from pathways implicated in previous studies. Nevertheless, the de novo and inherited genes contribute to a common protein-protein interaction network. We also identified structural variants (SVs) affecting non-coding regions, implicating recurrent deletions in the promoters of DLG2 and NR3C2. Loss of nr3c2 function in zebrafish disrupts sleep and social function, overlapping with human ASD-related phenotypes. These data support the utility of studying multiplex families in ASD and are available through the Hartwell Autism Research and Technology portal.


Assuntos
Transtorno do Espectro Autista/genética , Predisposição Genética para Doença/genética , Linhagem , Mapas de Interação de Proteínas/genética , Animais , Criança , Bases de Dados Genéticas , Modelos Animais de Doenças , Feminino , Deleção de Genes , Guanilato Quinases/genética , Humanos , Padrões de Herança/genética , Aprendizado de Máquina , Masculino , Núcleo Familiar , Regiões Promotoras Genéticas/genética , Receptores de Mineralocorticoides/genética , Fatores de Risco , Proteínas Supressoras de Tumor/genética , Sequenciamento Completo do Genoma , Peixe-Zebra/genética
18.
Medicine (Baltimore) ; 98(20): e15521, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31096452

RESUMO

The aim of this study was to develop an online collaborative map to enable researchers to locate, explore, and share cancer data.This 2-scale (global and country-level) cancer map adopts a database-driven model, which was implemented using the Google Map Application Programming Interface (API) and asynchronous JavaScript and XML (AJAX) technology. Seven visualization techniques were used to present data. Data on worldwide cancer mortality between 1950 and 2013 were taken from the International Agency for Research on Cancer (IARC) database. Incidence data were from the IARC CI5plus database. Survival data were from the IARC SURVCAN study. Prevalence data between 1990 and 2017 were from the Institute for Health Metrics and Evaluation's (IHME) catalog while demographic data were from the World Bank Data Catalog. Cancer data for Taiwan between 1991 and 2016 were obtained from the Department of Health and Welfare. This study used visualization techniques that included: a choropleth map to display the prevalence of cancer; a tornado diagram to show the age-standardized mortality rates of all cancers among men and women in 2013; a treemap to show a ranking of cancer mortality data; a sunburst chart to show mortality rates of all cancers by gender; a line chart to show mortality trends for all cancers; a bar chart to show mortality and incidence rates and a heatmap to show variations in cancer across different countries.The world cancer map generated by this study can be accessed at http://worldmap.csmu-liawyp.tw. Country-level mortality data are presented as crude and age-standardized rates.We used visualization methodologies and constructed an easily maintainable web-based user interface with cancer data from administrative regions in 150 countries. This serves as a platform that allows researchers to manage and disseminate cancer data.


Assuntos
Visualização de Dados , Mapeamento Geográfico , Saúde Global/estatística & dados numéricos , Mapas como Assunto , Neoplasias/epidemiologia , Feminino , Humanos , Internet , Masculino , Corpo Clínico Hospitalar , Neoplasias/mortalidade , Prevalência , Distribuição por Sexo , Taiwan/epidemiologia
19.
Oncotarget ; 9(41): 26342-26352, 2018 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-29899863

RESUMO

Nuclear Nrf2 (nNrf2) binding to the antioxidant response element may promote chemoresistance in colorectal cancer. However, the shuttling of Nrf2 between cytoplasm and nucleus in colon cancer cells has revealed the possibility that cytoplasmic location of Nrf2 (cNrf2) may play a specific role in chemoresistance. Transfection of a nuclear location sequence (NLS)-wild-type or NLS-mutated Nrf2 expression vector into a stable shNrf2 HCT116 clone using the MTT assay to examine whether chemoresistance induced by cNrf2 may be greater than nNrf2. Different specific inhibitors and small hairpin (sh)RNAs of targeting genes were used to verify the mechanistic action of cNrf2 in chemoresistance and further confirmed by an animal model. The association of cNrf2 with chemotherapeutic response in patients with colorectal cancer was statistically analyzed. The MTT assay indicated that cNrf2 may play a more important role than nNrf2 in conferring 5-fluorouracil (5-FU) and oxaliplatin resistance in HCT116 cells. Mechanistically, cNrf2-induced PSMD4 expression was responsible for chemoresistance in the NLS-mutated Nrf2-tranfected shNrf2HCT116 clone via the NF-κB/AKT/ß-catenin/ZEB1 cascades. The tumor burden induced by the NLS-mutated Nrf2-transfected shNrf2HCT116 clone was completely suppressed by treatment with 5-FU in combination with carfilzomib. A higher prevalence of unfavorable chemotherapeutic response in colorectal cancer patients with cNrf2, PSMD4-positive, p-p65-positive, and nuclear ß-catenin tumors was observed when compared to their counterparts. cNrf2 may play a more important role than nNrf2 in the chemoresistance of colorectal cancer. Activation of the NF-κB/AKT/ß-catenin/ZEB1 cascade by PSMD4 may be responsible for cNrf2-mediated chemoresistance. CONDENSED ABSTRACT: CNrf2 may play a more important role than nNrf2 in conferring 5-FU and oxaliplatin resistance. This observation in patients seemed to support the findings of the cell and animal models and suggested that PSMD4 may be responsible cNrf2-mediated chemoresistance via the NF-κB/AKT/ß-catenin /ZEB1 cascades.

20.
Chem Sci ; 9(10): 2645-2654, 2018 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-29732050

RESUMO

The CO2 reduction electrocatalyst [Fe4N(CO)12]- (abbrev. 1-) reduces CO2 to HCO2- in a two-electron, one-proton catalytic cycle. Here, we employ ab initio calculations to estimate the first two redox potentials of 1- and explore the pathway of a side reaction involving CO dissociation from 13-. Using the BP86 density functional approximation, the redox potentials were computed with a root mean squared error of 0.15 V with respect to experimental data. High temperature Born-Oppenheimer molecular dynamics was employed to discover a reaction pathway of CO dissociation from 13- with a reaction energy of +10.6 kcal mol-1 and an activation energy of 18.8 kcal mol-1; including harmonic free energy terms, this yields ΔGsep = 1.4 kcal mol-1 for fully separated species and ΔG‡ = +17.4 kcal mol-1, indicating CO dissociation is energetically accessible at ambient conditions. The analogous dissociation pathway from 12- has a reaction energy of 22.1 kcal mol-1 and an activation energy of 22.4 kcal mol-1 (ΔGsep = 12.8 kcal mol-1, ΔG‡ = +18.1 kcal mol-1). Our computed harmonic vibrational analysis of [Fe4N(CO)11]3- or 23- reveals a distinct CO-stretching peak red-shifted from the main CO-stretching band, pointing to a possible vibrational signature of dissociation. Multi-reference CASSCF calculations are used to check the assumptions of the density functional approximations that were used to obtain the majority of the results.

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