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2.
Anal Chem ; 96(3): 1345-1353, 2024 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-38190289

RESUMO

Designing a metal-organic framework (MOF)-derived nanozyme with highly dispersed active sites and high catalytic activity as well as robust structure for colorimetric biosensing of diverse biomolecules remains a substantial challenge. Here, an MOF-derived highly dispersed and pure α-cobalt confined in a nitrogen-doped carbon nanofiber (α-Co@NCNF) nanozyme with superior glucose oxidase (GOD)- and peroxidase (POD)-like activities was constructed for colorimetric assay of multiple biomolecules. Specifically, the α-Co@NCNF nanozyme was synthesized, utilizing in situ electrospinning Co-MOFs into polyacrylonitrile nanofiber (PAN) followed by a pyrolysis process. Taking advantage of the in situ electrospinning strategy, the α-Co nanoparticles were confined in continuous porous NCNF to restrict the growth and prevent the aggregation and oxidation during the pyrolysis process. The resulting special structure considerably improved the enzyme-like performance. A series of experiments validate that the enzyme-like activity of the α-Co@NCNF nanozyme was superior to that of Co@CoO@NCNF (derivatives from Co-MOFs grown on the surface of PAN nanofiber) and nature enzymes. Furthermore, α-Co@NCNF nanozyme-based colorimetric biosensing was developed for monitoring glucose, hydrogen peroxide (H2O2), and glutathione (GSH) and the corresponding linear ranges are 0.1-50 and 50-900 µM and 5-55 and 0.1-20 µM accompanied by the corresponding low detection of 0.03, 1.66, and 0.03 µM. The proposed method for the construction of α-Co@NCNF nanozyme with dual enzyme-like properties provides a new insight for designing novel nanozymes and has prospects for application in colorimetric biosensing.


Assuntos
Estruturas Metalorgânicas , Nanofibras , Peróxido de Hidrogênio , Estruturas Metalorgânicas/química , Carbono/química , Nitrogênio/química , Cobalto , Antioxidantes , Colorimetria/métodos
3.
Angew Chem Int Ed Engl ; : e202416104, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39353854

RESUMO

Copolymers with precise compositions and controlled sequences are great appealing for high-performance polymeric materials, but their synthesis is very challenging. In this study, tetrakis[tris(dimethylamino)phosphoranylidenamino] phosphonium chloride (P5Cl) and triethylboron (TEB) were chosen as the binary catalyst to synthesize both well-defined block and truly random poly(ester-carbonate) copolymers via the one-pot/one-step terpolymerization of epoxide/anhydride/CO2 under metal-free conditions. The bulky nature of phosphazenium cation not only led to loose cation-anion pairs and enhanced the reactivity, but also provided the chain-end an appropriate protection and improved the controllability. In particular, P5Cl/TEB with a molar ratio of 1/0.5 showed an extraordinary chemoselectivity for ring-opening alternating copolymerization (ROAC) of cyclohexene oxide (CHO) and phthalic anhydride (PA) first and then ROAC of CHO/CO2. Thus, well-defined block polyester-polycarbonate copolymers were synthesized by CHO/PA/CO2 terpolymerization. The chemoselectivity was easily tuned and the ROAC of CHO/PA and ROAC of CHO/CO2 occurred simultaneously with P5Cl/TEB = 1/2, producing truly random poly(ester-carbonate) copolymers from CHO/PA/CO2. In addition, this P5Cl/TEB catalyst and the strategy to regulate its chemoselectivity are versatile for various anhydrides, epoxides and initiators. Thus, poly(ester-carbonate) copolymers with varying sequences, compositions, and topologies are successfully synthesized, making it possible to compare their properties and to expand their applications.

4.
J Hepatol ; 75(1): 120-131, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33577921

RESUMO

BACKGROUND & AIMS: Gain of function (GOF) mutations in the CTNNB1 gene are one of the most frequent genetic events in hepatocellular carcinoma (HCC). T-box transcription factor 3 (TBX3) is a liver-specific target of the Wnt/ß-catenin pathway and thought to be an oncogene mediating activated ß-catenin-driven HCC formation. METHODS: We evaluated the expression pattern of TBX3 in human HCC specimens. Tbx3 was conditionally knocked out in murine HCC models by hydrodynamic tail vein injection of Cre together with c-Met and ΔN90-ß-catenin (c-Met/ß-catenin) in Tbx3flox/flox mice. TBX3 was overexpressed in human HCC cell lines to investigate the functions of TBX3 in vitro. RESULTS: A bimodal expression pattern of TBX3 in human HCC samples was detected: high expression of TBX3 in GOF CTNNB1 HCC and downregulation of TBX3 in non-CTNNB1 mutant tumors. High expression of TBX3 was associated with increased differentiation and decreased expression signatures of tumor growth. Using Tbx3flox/flox mice, we found that ablation of Tbx3 significantly accelerates c-Met/ß-catenin-driven HCC formation. Moreover, Tbx3(-) HCC demonstrated increased YAP/TAZ activity. The accelerated tumor growth induced by loss of TBX3 in c-Met/ß-catenin mouse HCC was successfully prevented by overexpression of LATS2, which inhibited YAP/TAZ activity. In human HCC cell lines, overexpression of TBX3 inhibited HCC cell growth as well as YAP/TAZ activation. A negative correlation between TBX3 and YAP/TAZ target genes was observed in human HCC samples. Mechanistically, phospholipase D1 (PLD1), a known positive regulator of YAP/TAZ, was identified as a novel transcriptional target repressed by TBX3. CONCLUSION: Our study suggests that TBX3 is induced by GOF CTNNB1 mutants and suppresses HCC growth by inactivating PLD1, thus leading to the inhibition of YAP/TAZ oncogenes. LAY SUMMARY: TBX3 is a liver-specific target of the Wnt/ß-catenin pathway and thought to be an oncogene in promoting liver cancer development. Herein, we demonstrate that TBX3 is in fact a tumor suppressor gene that restricts liver tumor growth. Strategies which increase TBX3 expression and/or activities may be effective for HCC treatment.


Assuntos
Carcinogênese/genética , Carcinoma Hepatocelular , Neoplasias Hepáticas , beta Catenina , Animais , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Descoberta de Drogas , Mutação com Ganho de Função , Regulação Neoplásica da Expressão Gênica , Genes Supressores de Tumor/fisiologia , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Camundongos , Camundongos Knockout , Fosfolipase D/metabolismo , Proteínas Proto-Oncogênicas c-met/metabolismo , Via de Sinalização Wnt , beta Catenina/genética , beta Catenina/metabolismo
5.
J Med Virol ; 93(8): 5095-5102, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33847377

RESUMO

We aimed to study the infection status and distribution of human papillomavirus (HPV) in Yangzhou City to provide precise guidance for the prevention and treatment of cervical cancer in this area. Reproductive tract secretions were collected from patients admitted at Subei People's Hospital over the past 3 years. Fifteen high-risk HPV (HR-HPV) genotypes were analyzed by fluorescent polymerase chain reaction. The positive rate of HR-HPV in 34 420 subjects was 23.56%. There was no significant difference in the rate of overall infection between males and females (χ 2 = 0.04; p = 0.952 > 0.05). The five genotypes with high infection rates in the population were HPV52, HPV58, HPV16, HPV51, and HPV39. Single infection was found to be dominant, primarily with the HPV52 genotype. The infection rate was higher in patients less than 20 years old and more than 60 years old. Most patients with cervical intraepithelial neoplasms 2/3 and cervical cancer were infected by HPV16, followed by those infected by HPV52 and HPV58. There was a significant difference in the infection rate of HPV16 among patients with different cervical lesions (χ 2 = 31.660; p < 0.01), and the infection rate of HPV16 was higher in patients with cervical cancer than in healthy individuals. Single infection was dominant among the study patients with HPV infection in Yangzhou city. There was no significant difference in infection rate and genotype distribution between males and females. The infection rate in young and old women was higher, and the rate increased with age (>20 years).


Assuntos
Papillomaviridae/genética , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/virologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , China/epidemiologia , Cidades/epidemiologia , Coinfecção/epidemiologia , Coinfecção/virologia , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Papillomaviridae/classificação , Papillomaviridae/isolamento & purificação , Prevalência , Neoplasias do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/virologia , Adulto Jovem , Displasia do Colo do Útero/epidemiologia , Displasia do Colo do Útero/virologia
6.
Gut ; 69(4): 641-651, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31383772

RESUMO

OBJECTIVE: Although a subset of genetic loci have been associated with gastric cancer (GC) risk, the underlying mechanisms are largely unknown. We aimed to identify new susceptibility genes and elucidate their mechanisms in GC development. DESIGN: We conducted a meta-analysis of four genome-wide association studies (GWASs) encompassing 3771 cases and 5426 controls. After targeted sequencing and functional annotation, we performed in vitro and in vivo experiments to confirm the functions of genetic variants and candidate genes. Moreover, we selected 33 promising variants for two-stage replication in 7035 cases and 8323 controls from other five studies. RESULTS: The meta-analysis of GWASs identified three loci at 1q22, 5p13.1 and 10q23.33 associated with GC risk at p<5×10-8 and replicated seven known loci at p<0.05. At 5p13.1, the risk rs59133000[C] allele enhanced the binding affinity of NF-κB1 (nuclear factor kappa B subunit 1) to the promoter of PRKAA1, resulting in a reduced promoter activity and lower expression. The knockout of PRKAA1 promoted both GC cell proliferation and xenograft tumour growth in nude mice. At 10q23.33, the rs3781266[C] and rs3740365[T] risk alleles in complete linkage disequilibrium disrupted and created, respectively, the binding motifs of POU2F1 and PAX3, resulting in an increased enhancer activity and expression of NOC3L, while the NOC3L knockdown suppressed GC cell growth. Moreover, two new loci at 3q11.2 (OR=1.21, p=4.56×10-9) and 4q28.1 (OR=1.14, p=3.33×10-11) were associated with GC risk. CONCLUSION: We identified 12 loci to be associated with GC risk in Chinese populations and deciphered the mechanisms of PRKAA1 at 5p13.1 and NOC3L at 10q23.33 in gastric tumourigenesis.


Assuntos
Povo Asiático/genética , Predisposição Genética para Doença/genética , Neoplasias Gástricas/genética , China , Estudo de Associação Genômica Ampla , Humanos
7.
Lancet Oncol ; 21(10): 1378-1386, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33002439

RESUMO

BACKGROUND: Genetic variants and lifestyle factors have been associated with gastric cancer risk, but the extent to which an increased genetic risk can be offset by a healthy lifestyle remains unknown. We aimed to establish a genetic risk model for gastric cancer and assess the benefits of adhering to a healthy lifestyle in individuals with a high genetic risk. METHODS: In this meta-analysis and prospective cohort study, we first did a fixed-effects meta-analysis of the association between genetic variants and gastric cancer in six independent genome-wide association studies (GWAS) with a case-control study design. These GWAS comprised 21 168 Han Chinese individuals, of whom 10 254 had gastric cancer and 10 914 geographically matched controls did not. Using summary statistics from the meta-analysis, we constructed five polygenic risk scores in a range of thresholds (p=5 × 10-4 p=5 × 10-5 p=5 × 10-6 p=5 × 10-7, and p=5 × 10-8) for gastric cancer. We then applied these scores to an independent, prospective, nationwide cohort of 100 220 individuals from the China Kadoorie Biobank (CKB), with more than 10 years of follow-up. The relative and absolute risk of incident gastric cancer associated with healthy lifestyle factors (defined as not smoking, never consuming alcohol, the low consumption of preserved foods, and the frequent intake of fresh fruits and vegetables), was assessed and stratified by genetic risk (low [quintile 1 of the polygenic risk score], intermediate [quintile 2-4 of the polygenic risk score], and high [quintile 5 of the polygenic risk score]). Individuals with a favourable lifestyle were considered as those who adopted all four healthy lifestyle factors, those with an intermediate lifestyle adopted two or three factors, and those with an unfavourable lifestyle adopted none or one factor. FINDINGS: The polygenic risk score derived from 112 single-nucleotide polymorphisms (p<5 × 10-5) showed the strongest association with gastric cancer risk (p=7·56 × 10-10). When this polygenic risk score was applied to the CKB cohort, we found that there was a significant increase in the relative risk of incident gastric cancer across the quintiles of the polygenic risk score (ptrend<0·0001). Compared with individuals who had a low genetic risk, those with an intermediate genetic risk (hazard ratio [HR] 1·54 [95% CI 1·22-1·94], p=2·67 × 10-4) and a high genetic risk (2·08 [1·61-2·69], p<0·0001) had a greater risk of gastric cancer. A similar increase in the relative risk of incident gastric cancer was observed across the lifestyle categories (ptrend<0·0001), with a higher risk of gastric cancer in those with an unfavourable lifestyle than those with a favourable lifestyle (2·03 [1·46-2·83], p<0·0001). Participants with a high genetic risk and a favourable lifestyle had a lower risk of gastric cancer than those with a high genetic risk and an unfavourable lifestyle (0·53 [0·29-0·99], p=0·048), with an absolute risk reduction of 1·12% (95% CI 0·62-1·56). INTERPRETATION: Chinese individuals at an increased risk of incident gastric cancer could be identified by use of our newly developed polygenic risk score. Compared with individuals at a high genetic risk who adopt an unhealthy lifestyle, those who adopt a healthy lifestyle could substantially reduce their risk of incident gastric cancer. FUNDING: National Key R&D Program of China, National Natural Science Foundation of China, 333 High-Level Talents Cultivation Project of Jiangsu Province, and China Postdoctoral Science Foundation.


Assuntos
Predisposição Genética para Doença/genética , Estilo de Vida Saudável , Neoplasias Gástricas/genética , Adulto , Idoso , Povo Asiático , China/epidemiologia , Feminino , Seguimentos , Predisposição Genética para Doença/epidemiologia , Predisposição Genética para Doença/psicologia , Estudo de Associação Genômica Ampla/estatística & dados numéricos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Herança Multifatorial , Polimorfismo de Nucleotídeo Único , Estudos Prospectivos , Fatores de Risco , Neoplasias Gástricas/epidemiologia , Neoplasias Gástricas/psicologia
10.
Analyst ; 145(9): 3283-3288, 2020 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-32253397

RESUMO

In this research, a novel manganese dioxide nanorod-anchored graphene oxide (MnO2 NRs/GO) composite was synthesized by a simple hydrothermal method for electrochemical sensing application. A highly sensitive electrochemical sensor for dopamine (DA) was constructed by modifying glassy carbon electrode (GCE) with MnO2 NRs/GO. The morphology and performance of the composite material and modified GCEs were investigated by using scanning electron microscopy (SEM), X-ray diffraction (XRD) and cyclic voltammetry (CV), respectively. The resultant MnO2 NRs/GO composite has a large electroactive area and shows excellent electrochemical activity toward DA. Under the optimal conditions, the DA sensor shows a linear response in the DA concentration ranges of 0.1 µM-0.08 mM and 0.08-0.41 mM with a low detection limit of 0.027 µM and a high sensitivity of 602.4 µA·mM-1·cm-2. The MnO2 NRs/GO composite provides a promising platform for the construction of a highly sensitive and selective sensor of DA.


Assuntos
Dopamina/análise , Técnicas Eletroquímicas/métodos , Grafite/química , Compostos de Manganês/química , Nanocompostos/química , Nanotubos/química , Óxidos/química , Dopamina/sangue , Dopamina/química , Eletrodos , Humanos , Limite de Detecção , Oxirredução , Reprodutibilidade dos Testes
11.
Future Oncol ; 16(12): 733-748, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32285687

RESUMO

Aim: To predict the occurrence of bone metastases and prognosis among patients with gastric cancer on a population level. Materials & methods: Data were obtained from the SEER database (2010-2016). Multivariable logistic regression and multivariable Cox regression were used to determine factors that predict the occurrence of bone metastasis and prognosis. Results: Cardia cancer, younger age, white race, poor differentiation grade, higher N stage, diffuse-type were positively associated with the presence of bone metastasis. For gastric cancer patients with bone metastasis, the median survival time was longer (9.0 months) among patients with surgery of primary site compared with those without surgery (3.0 months). Conclusion: According to the results of risk assessment, clinical efforts should be targeted to focus on screening high-risk patients.


Assuntos
Neoplasias Ósseas/mortalidade , Neoplasias Ósseas/secundário , Neoplasias Gástricas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Ósseas/epidemiologia , Neoplasias Ósseas/terapia , Estudos de Coortes , Terapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Prognóstico , Modelos de Riscos Proporcionais , Medição de Risco , Fatores de Risco , Programa de SEER , Neoplasias Gástricas/epidemiologia , Adulto Jovem
20.
Gastroenterology ; 152(8): 2011-2021, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28246015

RESUMO

BACKGROUND & AIMS: Several genetic variants have been associated with gastric cancer risk, although these account for only a fraction of cases of gastric cancer. We aimed to identify low-frequency and other genetic variants that determine gastric cancer susceptibility. METHODS: We performed exome array analysis of DNA in blood samples from 1113 patients with gastric cancer, collected at hospitals from 2006 to 2010 in China, and 1848 individuals without cancer (controls) undergoing physical examinations. Among 71,290 variants analyzed (including 25,784 common variants), 24 variants were selected and replicated in an analysis of DNA in blood samples from 4687 additional cases of gastric cancer and 5780 controls. We compared expression of candidate genes in tumor vs normal gastric tissues using data from TCGA and performed functional annotation analyses. An immortalized human gastric epithelial cell line (GES1) and 7 human gastric cancer lines were used to express transgenes, knock down gene expression (with small interfering RNAs), disrupt genes (using the CRISPR/Cas9 system), or assess expression of reporter constructs. We measured cell proliferation, colony formation, invasion, and migration, and assessed growth of xenograft tumors in nude mice. RESULTS: A low-frequency missense variant rs112754928 in the SPOC domain containing 1 gene (SPOCD1; encoding p.Arg71Trp), at 1p35.2, was reproducibly associated with reduced risk of gastric cancer (odds ratio, 0.56; P = 3.48 × 10-8). SPOCD1 was overexpressed in gastric tumors, and knockout of SPOCD1 reduced gastric cancer cell proliferation, invasive activity, and migration, as well as growth of xenograft tumors in nude mice. We also associated the variant rs1679709 at 6p22.1 with reduced risk for gastric cancer (odds ratio, 0.80; P = 1.17 × 10-13). The protective allele rs1679709-A correlated with the surrounding haplotype rs2799077-T-rs2799079-C, which reduced the enhancer activity of this site to decrease expression of the butyrophilin subfamily 3 member A2 gene (BTN3A2). BTN3A2 is overexpressed in gastric tumors, and deletion of BTN3A2 inhibited proliferation, migration, and invasion of gastric cancer cells. CONCLUSIONS: We have associated variants at 1p35.2 and 6p22.1 with gastric cancer risk, indicating a role for SPOCD1 and BTN3A2 in gastric carcinogenesis.


Assuntos
Biomarcadores Tumorais/genética , Butirofilinas/genética , Exossomos/genética , Variação Genética , Neoplasias Gástricas/genética , Idoso , Animais , Biomarcadores Tumorais/metabolismo , Butirofilinas/metabolismo , Sistemas CRISPR-Cas , Estudos de Casos e Controles , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , China , Feminino , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Modelos Logísticos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Análise Multivariada , Invasividade Neoplásica , Razão de Chances , Fenótipo , Interferência de RNA , Fatores de Risco , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Fatores de Tempo , Transfecção , Carga Tumoral
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