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1.
Adv Mater ; : e2313749, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38578135

RESUMO

Developing coordination complexes (such as metal-organic frameworks, MOFs) with circularly polarized luminescence (CPL) is currently attracting tremendous attention and remains a significant challenge in achieving MOF with circularly polarized afterglow. Herein, MOFs-based circularly polarized afterglow is first reported by combining the chiral induction approach and tuning the afterglow times by using the auxiliary ligands regulation strategy. The obtained chiral R/S-ZnIDC, R/S-ZnIDC(bpy), and R/S-ZnIDC(bpe)(IDC = 1H-Imidazole-4,5-dicarboxylate, bpy = 4,4'-Bipyridine, bpe = trans-1,2-Bis(4-pyridyl) ethylene) containing a similar structure unit display different afterglow times with 3, 1, and <0.1 s respectively which attribute to that the longer auxiliary ligand hinders the energy transfer through the hydrogen bonding. The obtained chiral complexes reveal a strong chiral signal, obvious photoluminescence afterglow feature, and strong CPL performance (glum up to 3.7 × 10-2). Furthermore, the photo-curing 3D printing method is first proposed to prepare various chiral MOFs based monoliths from 2D patterns to 3D scaffolds for anti-counterfeiting and information encryption applications. This work not only develops chiral complexes monoliths by photo-curing 3D printing technique but opens a new strategy to achieve tunable CPL afterglow in optical applications.

2.
Stem Cells ; 39(10): 1298-1309, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34182610

RESUMO

Programmed death-ligand 1 (PD-L1), an immune checkpoint ligand, is recognized as a potential target for cancer immunotherapy as well as for the induction of transplantation tolerance. However, how the crosstalk between stem cell programming and cytokine signaling regulates PD-L1 expression during stem cell differentiation and cancer cell plasticity remains unclear. Herein, we reported that PD-L1 expression was regulated by SOX2 during embryonic stem cell (ESC) differentiation and lung cancer cell plasticity. PD-L1 was induced during ESC differentiation to fibroblasts and was downregulated during SOX2-mediated reprogramming of fibroblasts to induced pluripotent stem cells (iPSCs). Furthermore, SOX2 activation affected cancer cell plasticity and inhibited PD-L1 expression in lung cancer cells. We discovered that the H3K27ac signal at the PD-L1 locus was enhanced during ESC differentiation to fibroblasts as well as during cancer plasticity of SOX2-positive lung cancer cells to SOX2-negative counterparts. Romidepsin, an epigenetic modifier, induced PD-L1 expression in lung cancer cells, whereas TGF-ß stimulation downregulated SOX2 but upregulated PD-L1 expression in lung cancer cells. Furthermore, in addition to PD-L1, the expressions of EGFR and its ligand HBEGF were downregulated by activation of endogenous SOX2 expression during lung cancer cell plasticity and iPSC reprogramming, and the activation of EGFR signaling by HBEGF upregulated PD-L1 expression in lung cancer cells. Together, our results reveal the crosstalk between SOX2 programming and cytokine stimulation influences PD-L1 expression, and these findings may provide insights into PD-L1-mediated therapeutics.


Assuntos
Antígeno B7-H1 , Epigênese Genética , Neoplasias Pulmonares , Antígeno B7-H1/metabolismo , Diferenciação Celular/genética , Plasticidade Celular/genética , Citocinas/metabolismo , Receptores ErbB/metabolismo , Humanos , Ligantes , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Células-Tronco/citologia
3.
Carcinogenesis ; 42(7): 951-960, 2021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-33993270

RESUMO

Inhibitors of DNA binding and cell differentiation (ID) proteins regulate cellular differentiation and tumor progression. Whether ID family proteins serve as a linkage between pathological differentiation and cancer stemness in colorectal cancer is largely unknown. Here, the expression of ID4, but not other ID family proteins, was enriched in LGR5-high colon cancer stem cells. Its high expression was associated with poor pathological differentiation of colorectal tumors and shorter survival in patients. Knockdown of ID4 inhibited the growth and dissemination of colon cancer cells, while enhancing chemosensitivity. Through gene expression profiling analysis, brain-derived neurotrophic factor (BDNF) was identified as a downstream target of ID4 expression in colorectal cancer. BDNF knockdown decreased the growth and migration of colon cancer cells, and its expression enhanced dissemination, anoikis resistance and chemoresistance. ID4 silencing attenuated the epithelial-to-mesenchymal transition pattern in colon cancer cells. Gene cluster analysis revealed that ID4 and BDNF expression was clustered with mesenchymal markers and distant from epithelial genes. BDNF silencing decreased the expression of mesenchymal markers Vimentin, CDH2 and SNAI1. These findings demonstrated that ID4-BDNF signaling regulates colorectal cancer survival, with the potential to serve as a prognostic marker in colorectal cancer.


Assuntos
Biomarcadores Tumorais/metabolismo , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Carcinogênese/patologia , Neoplasias Colorretais/patologia , Regulação Neoplásica da Expressão Gênica , Proteínas Inibidoras de Diferenciação/metabolismo , Células-Tronco Neoplásicas/patologia , Apoptose , Biomarcadores Tumorais/genética , Fator Neurotrófico Derivado do Encéfalo/genética , Carcinogênese/genética , Carcinogênese/metabolismo , Ciclo Celular , Movimento Celular , Proliferação de Células , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Transição Epitelial-Mesenquimal , Humanos , Proteínas Inibidoras de Diferenciação/genética , Células-Tronco Neoplásicas/metabolismo , Prognóstico , Taxa de Sobrevida , Células Tumorais Cultivadas
4.
J Hazard Mater ; 414: 125537, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-33676243

RESUMO

Microplastics are ubiquitous in marine environments and may cause unexpected ecological effects. This study adopted a whole life-cycle exposure to illuminate the impact of polystyrene microplastics on life-history strategies of marine medaka (Oryzias melastigma), including the hatching of embryos, growth and reproduction of F0 generation, and embryonic and larval development of F1 offspring. Microplastics accumulated on the eggshell and reduced embryonic hatching rate and larval body length and weight. Similarly, 150 days of microplastic exposure decreased body mass and gonadosomatic index of adult fish, but accelerated sexual maturity of female fish, showing a trade-off between growth and reproduction. Microplastic exposure also caused obvious histopathological damages to gonads and decreased egg productions and fertilization rates. Moreover, parental microplastic exposure induced elevated heartbeats, premature hatching, and slow growth in F1 offspring. Anti-oxidative stress response, sex hormone disruption, and disturbed transcription of steroidogenic genes in the reproductive axis could partially explain the reproduction impairment and transgenerational trade-offs. Furthermore, transcriptome analysis revealed that the steroid hormone biosynthesis and cytochrome P450 pathways in the testes of male fish were significantly affected after 20 µg/L microplastic exposure. These findings suggest that microplastic pollution may be an emerging threat to the sustainability of marine fish population.


Assuntos
Oryzias , Poluentes Químicos da Água , Animais , Feminino , Masculino , Microplásticos , Oryzias/genética , Plásticos/toxicidade , Poliestirenos/toxicidade , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
5.
Sci Rep ; 10(1): 8261, 2020 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-32427884

RESUMO

Signaling elicited by the stem cell factors SOX2, OCT4, KLF4, and MYC not only mediates reprogramming of differentiated cells to pluripotency but has also been correlated with tumor malignancy. In this study, we found SOX2 expression signifies poor recurrence-free survival and correlates with advanced pathological grade in bladder cancer. SOX2 silencing attenuated bladder cancer cell growth, while its expression promoted cancer cell survival and proliferation. Under low-serum stress, SOX2 expression promoted AKT phosphorylation and bladder cancer cells' spheroid-forming capability. Furthermore, pharmacological inhibition of AKT phosphorylation, using MK2206, inhibited the SOX2-mediated spheroid formation of bladder cancer cells. Gene expression profiling showed that SOX2 expression, in turn, induced IGF2 expression, while SOX2 silencing inhibited IGF2 expression. Moreover, knocking down IGF2 and IGF1R diminished bladder cancer cell growth. Lastly, pharmacological inhibition of IGF1R, using linsitinib, also inhibited the SOX2-mediated spheroid formation of bladder cancer cells under low-serum stress. Our findings indicate the SOX2-IGF2 signaling affects the aggressiveness of bladder cancer cell growth. This signaling could be a promising biomarker and therapeutic target for bladder cancer intervention.


Assuntos
Fator de Crescimento Insulin-Like II/metabolismo , Fatores de Transcrição SOXB1/metabolismo , Neoplasias da Bexiga Urinária/metabolismo , Humanos , Fator de Crescimento Insulin-Like II/genética , Fator 4 Semelhante a Kruppel , Fosforilação , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor IGF Tipo 1/genética , Receptor IGF Tipo 1/metabolismo , Fatores de Transcrição SOXB1/genética , Transdução de Sinais , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/patologia
6.
Sci Rep ; 10(1): 2066, 2020 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-32034239

RESUMO

Changes in expression patterns of serum carcinoembryonic antigen at initial diagnosis (CEAIn) and disease progression (CEAPd) in lung cancer patients under EGFR-tyrosine kinase inhibitors (TKI) treatment may reflect different tumor progression profiles. Of the 1736 lung cancer patients identified from the cancer registry group between 2011 to 2016, we selected 517 patients with advanced stage adenocarcinoma, data on EGFR mutation status and CEAIn, among whom were 288 patients with data on CEAPd, eligible for inclusion in the correlation analysis of clinical characteristics and survival. Multivariable analysis revealed that CEAIn expression was associated with poor progression-free survival in patients harboring mutant EGFR. Moreover, CEAIn and CEAPd were associated with the good and poor post-progression survival, respectively, in the EGFR-mutant group. Cell line experiments revealed that CEA expression and cancer dissemination can be affected by EGFR-TKI selection. EGFR-mutant patients, exhibiting high CEAIn (≥5 ng/mL) and low CEAPd (<5 ng/mL), showed a potential toward displaying new metastasis. Taken together, these findings support the conclusion that EGFR mutation status is a critical factor in determining prognostic potential of CEAIn and CEAPd in patients under EGFR-TKI treatment, and CEAIn and CEAPd are associated with distinct cancer progression profiles.


Assuntos
Antígeno Carcinoembrionário/sangue , Neoplasias Pulmonares/sangue , Adenocarcinoma/sangue , Adenocarcinoma/diagnóstico , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Idoso , Progressão da Doença , Receptores ErbB/genética , Feminino , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Intervalo Livre de Progressão , Análise de Sobrevida
7.
Environ Pollut ; 254(Pt B): 113024, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31454586

RESUMO

The ubiquity of microplastics in the world's ocean has aroused great concern. However, the ecological effects of microplastics at environmentally realistic concentrations are unclear. Here we showed that exposure of marine medaka (Oryzias melastigma) to environmentally relevant concentrations of 10 µm polystyrene microplastics for 60 days not only led to microplastic accumulation in the gill, intestine, and liver, but also caused oxidative stress and histological changes. Moreover, 2, 20, and 200 µg/L microplastics delayed gonad maturation and decreased the fecundity of female fish. Alterations of the hypothalamus-pituitary-gonadal (HPG) axis were investigated to reveal the underlying mechanisms, and gene transcription analysis showed that microplastic exposure had significantly negative regulatory effects in female HPG axis. Transcription of genes involved in the steroidogenesis pathway in females were also downregulated. This disruption resulted in decreased concentrations of 17ß-estradiol (E2) and testosterone (T) in female plasma. Furthermore, parental exposure to 20 µg/L microplastics postponed the incubation time and decreased the hatching rate, heart rate, and body length of the offspring. Overall, the present study demonstrated for the first time that environmentally relevant concentrations of microplastics had adverse effects on the reproduction of marine medaka and might pose a potential threat to marine fish populations.


Assuntos
Oryzias/fisiologia , Plásticos/toxicidade , Poliestirenos/toxicidade , Animais , Tamanho Corporal , Estradiol/metabolismo , Feminino , Fígado/efeitos dos fármacos , Fígado/crescimento & desenvolvimento , Masculino , Oryzias/crescimento & desenvolvimento , Estresse Oxidativo/efeitos dos fármacos , Reprodução/efeitos dos fármacos , Especificidade da Espécie , Testosterona/metabolismo , Poluentes Químicos da Água/toxicidade
8.
Mar Pollut Bull ; 133: 415-422, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30041330

RESUMO

Estrogenic pollution has aroused great concern for its adverse effects on marine organisms. This study aimed to establish biomarker-based methods for detecting environmental estrogens using vitellogenin (Vtg) of teleost fishes inhabiting coastal areas of China. Firstly, Vtgs in marbled flounder (Pseudopleuronectes yokohamae), black rockfish (Sebastes schlegelii) and fat greenling (Hexagrammos otakii) were purified, characterized and used to prepare antibodies. Then, Vtg ELISA for each species was developed using purified Vtg and its antibody. Marbled flounder Vtg ELISA had a working range of 3.9-500 ng/mL and a detection limit of 2.1 ng/mL, and black rockfish Vtg ELISA had strong cross-reactivity with marbled flounder Vtg. Furthermore, Vtg induction in male marbled flounder exposed to pentadecafluorooctanoic acid (PFOA) was measured by developed ELISA. Plasma Vtg concentrations were significantly increased with PFOA concentrations in seawater and fish muscle. Therefore, Vtg ELISAs for these species might be useful tools for monitoring marine environmental estrogens.


Assuntos
Biomarcadores Ambientais , Ensaio de Imunoadsorção Enzimática/métodos , Peixes , Vitelogeninas/análise , Animais , Caprilatos/toxicidade , China , Ecotoxicologia/métodos , Monitoramento Ambiental/métodos , Estrogênios/análise , Peixes/fisiologia , Linguado , Fluorocarbonos/toxicidade , Masculino , Reprodutibilidade dos Testes , Vitelogeninas/metabolismo , Poluentes Químicos da Água/toxicidade , Poluição Química da Água/análise
9.
Environ Sci Pollut Res Int ; 25(25): 25036-25044, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29934832

RESUMO

Guppy (Poecilia reticulata) is a promising model organism in toxicological studies, and vitellogenin (Vtg) is a commonly used biomarker for environmental estrogens. Although an ELISA for guppy Vtg has been developed previously, we found that guppy had two forms of Vtgs. In this study, two Vtgs were characterized and enzyme-linked immunosorbent assays (ELISAs) for each Vtg were developed. Two Vtgs purified from 17ß-estradiol (E2)-exposed guppy were characterized as phospholipoglycoproteins with molecular weights of ~ 520 and ~ 480 kDa, respectively. In SDS-PAGE, one purified Vtg appeared as three major bands of ~ 210, ~ 126, and ~ 102 kDa, and the other revealed a clear band of ~ 68 kDa. Matrix-assisted laser desorption/ionization-time of flight/time of flight mass spectrometry analysis showed that they were VtgAb and VtgC. Using purified Vtgs and their corresponding antibodies, two sandwich ELISAs with working ranges of 7.8~1000 and 15.6~500 ng/mL were developed. Precision tests showed that intra- and inter-assay coefficients of variations of both ELISAs were below 10%. Parallelism between Vtg standard curves and serial dilutions of whole body homogenate from E2-exposed guppy confirmed that two ELISAs could quantify guppy Vtgs. Furthermore, two ELISAs were used to measure Vtg inductions in liver, caudal fin and whole body of male guppy exposed to 17a-ethinylestradiol to validate their use for detecting estrogenic effects of exogenous chemicals. These homologous Vtg ELISAs will promote the use of guppy as a model organism to study estrogenic chemicals.


Assuntos
Monitoramento Ambiental/métodos , Ensaio de Imunoadsorção Enzimática/métodos , Poecilia/metabolismo , Vitelogeninas/metabolismo , Animais , Anticorpos , Biomarcadores , Eletroforese em Gel de Poliacrilamida , Estradiol , Estrogênios , Etinilestradiol , Masculino , Vitelogeninas/análise
10.
Sci Rep ; 7(1): 7647, 2017 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-28794440

RESUMO

Guppy (Poecilia reticulata) is an ideal model for studying environmental estrogens, and its large caudal fin has a high capacity to regenerate. This study analyzed the feasibility of caudal fin for detecting vitellogenin (Vtg), the most commonly used biomarker of environmental estrogens. Firstly, a sandwich ELISA for guppy Vtg was developed using purified lipovitellin and its antibody and it had a working range of 7.8-1000 ng/mL and detection limit of 3.1 ng/mL. The ELISA was used to detect tissue distribution of Vtg. In male guppy exposed to 50 and 100 ng/L 17ß-estradiol (E2), Vtg concentration in caudal fin was higher than that in whole fish, brain, eyes, gonad, and skin, and was close to that in the liver. Furthermore, male guppies were exposed to environmental concentrations of 17a-ethinylestradiol (EE2) and bisphenol S (BPS) to validate the utility of caudal fin Vtg for detecting estrogenic activities. The lowest observed effect concentration of EE2 and BPS were lower than 2 ng/L and 1 µg/L, which were below or equal to the values reported for other species, demonstrating that caudal fin Vtg was highly sensitive to estrogenic chemicals. Therefore, caudal fins of guppies are suggested as alternative samples for Vtg biomarker detection.


Assuntos
Nadadeiras de Animais/metabolismo , Biomarcadores , Estrogênios/farmacologia , Poecilia/fisiologia , Vitelogeninas/biossíntese , Animais , Western Blotting , Proteínas do Ovo/análise , Proteínas do Ovo/biossíntese , Exposição Ambiental , Ensaio de Imunoadsorção Enzimática , Feminino , Masculino , Fenótipo , Vitelogeninas/análise
11.
Sci Rep ; 7: 40846, 2017 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-28134297

RESUMO

High performance Mg-8.2Gd-3.8Y-1.0Zn-0.4Zr alloy with high strength and excellent ductility has been successfully developed by hot extrusion. The effect of plate-shaped long period stacking ordered (LPSO) phases and solute-segregated stacking faults (SFs) on the dynamically recrystallization (DRX) behavior was analyzed. The plate-shaped LPSO phases stimulate the DRX by particle stimulated nucleation mechanism, leading to higher DRX ratio and weaker basal texture. While for the alloy with dense fine SFs inside the original grains, discontinuous DRX initially occurs at the original grain boundaries, and the DRX is obviously restricted. Consequently, alloy containing dense SFs exhibits higher strength but lower ductility compared with alloy with plated-shaped LPSO phases.

12.
Sci Rep ; 6: 38824, 2016 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-27941839

RESUMO

In this work, graphene nanoplatelets (GNPs) reinforced magnesium (Mg) matrix composites were synthesised using the multi-step dispersion route. Well-dispersed but inhomogeneously distributed GNPs were obtained in the matrix. Compared with the monolithic alloy, the nanocomposites exhibited dramatically enhanced Young's modulus, yield strength and ultimate tensile strength and relatively high plasticity, which mainly attributed to the significant heterogeneous laminated microstructure induced by the addition of GNPs. With increasing of the concentration of GNPs, mechanical properties of the composites were gradually improved. Especially, the strengthening efficiency of all the composites exceeded 100%, which was significantly higher than that of carbon nanotubes reinforced Mg matrix composites. The grain refinement and load transfer provided by the two-dimensional and wrinkled surface structure of GNPs were the dominated strengthening mechanisms of the composites. This investigation develops a new method for incorporating GNPs in metals for fabricating high-performance composites.

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