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1.
J Biol Chem ; 300(8): 107570, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39019216

RESUMO

During vascular development, radial glial cells (RGCs) regulate vascular patterning in the trunk and contribute to the early differentiation of the blood-brain barrier. Ablation of RGCs results in excessive sprouting vessels or the absence of bilateral vertebral arteries. However, interactions of RGCs with later brain vascular networks after pattern formation remain unknown. Here, we generated a her4.3 transgenic line to label RGCs and applied the metronidazole/nitroreductase system to ablate her4.3+ RGCs. The ablation of her4.3+ RGCs led to the collapse of the cerebral vascular network, disruption of the blood-brain barrier, and downregulation of Wnt signaling. The inhibition of Wnt signaling resulted in the collapse of cerebral vasculature, similar to that caused by her4.3+ RGC ablation. The defects in the maintenance of brain vasculature resulting from the absence of her4.3+ RGCs were partially rescued by the activation of Wnt signaling or overexpression of Wnt7aa or Wnt7bb. Together, our study suggests that her4.3+ RGCs maintain the cerebral vascular network through Wnt signaling.


Assuntos
Encéfalo , Células Ependimogliais , Camundongos Transgênicos , Proteínas Wnt , Via de Sinalização Wnt , Animais , Camundongos , Proteínas Wnt/metabolismo , Proteínas Wnt/genética , Células Ependimogliais/metabolismo , Células Ependimogliais/citologia , Encéfalo/metabolismo , Encéfalo/irrigação sanguínea , Barreira Hematoencefálica/metabolismo , Neovascularização Fisiológica , Proteínas Proto-Oncogênicas
2.
Development ; 149(13)2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35694896

RESUMO

After ischemic stroke, promotion of vascular regeneration without causing uncontrolled vessel growth appears to be the major challenge for pro-angiogenic therapies. The molecular mechanisms underlying how nascent blood vessels (BVs) are correctly guided into the post-ischemic infarction area remain unknown. Here, using a zebrafish cerebrovascular injury model, we show that chemokine signaling provides crucial guidance cues to determine the growing direction of ingrown lymphatic vessels (iLVs) and, in turn, that of nascent BVs. The chemokine receptor Cxcr4a is transcriptionally activated in the iLVs after injury, whereas its ligand Cxcl12b is expressed in the residual central BVs, the destinations of iLV ingrowth. Mutant and mosaic studies indicate that Cxcl12b/Cxcr4a-mediated chemotaxis is necessary and sufficient to determine the growing direction of iLVs and nascent BVs. This study provides a molecular basis for how the vessel directionality of cerebrovascular regeneration is properly determined, suggesting potential application of Cxcl12b/Cxcr4a in the development of post-ischemic pro-angiogenic therapies.


Assuntos
Vasos Linfáticos , Peixe-Zebra , Animais , Encéfalo/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Vasos Linfáticos/metabolismo , Receptores CXCR4/genética , Receptores CXCR4/metabolismo , Peixe-Zebra/genética
3.
Mol Carcinog ; 63(2): 314-325, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37937915

RESUMO

Protein kinase B (AKT) plays a pivotal in regulating cell migration, proliferation, apoptosis, and survival, making it a prominent target for anticancer therapy. While the kinase activity of AKT has been extensively explored, its dephosphorylation have largely remained uncharted. Herein, we aimed to unravel the molecular mechanisms governing AKT dephosphorylation, with a specific emphasis on dual-specificity phosphatases DUSP22. Our investigation sought to shed light on the potential of DUSP22 as a potential therapeutic target for non-small cell lung cancer (NSCLC). To determine the expression level of DUSP22 in NSCLC cell lines, the gene expression profiling interactive analysis (GEPIA) and Oncomine database were searched. Additionally, the effect of DUSP22 on patient survival was analyzed with Kaplan-Meier database. Antitumor effects of DUSP22 were tested in A549 and H1299 cell lines. Experiments are based on: (1) cell viability determined by the cell counting kit-8 assay and colony-formation assay; (2) cell migratory ability assessed through the scratch assay and the transwell migration assay; (3) the mechanism behind the antitumor effects of DUSP22 dissected with co-immunoprecipitation (Co-IP) and in vitro kinase assays. Our study revealed a significant downregulation of DUSP22 in both NSCLC cell lines and tissues. Meanwhile, survival rate analysis results demonstrated that reduced DUSP22 expression was correlated with poorer overall survival in lung cancer patients. Moreover, DUSP22 exhibited an inhibitory effect on the cell viability and migratory capacity of A549 and H1299 cells. This inhibition was accompanied by the decrease in the phosphorylation of AKT and p38. Mechanistically, the phosphatase domain of DUSP22 interacted with AKT, resulting in the inhibition of AKT phosphorylation. This inhibitory effect was contingent upon the phosphatase activity of DUSP22. These findings provide compelling evidence that DUSP22 directly interacted with AKT, leading to the dephosphorylation of AKT at S473 and T308 residues, ultimately curbing the proliferation and migration of lung cancer cells. Additionally, our results also highlight a preclinical rationale for utilizing DUSP22 as a prognostic marker in NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Fosfatases de Especificidade Dupla/genética , Fosfatases de Especificidade Dupla/metabolismo , Neoplasias Pulmonares/patologia , Fosfatases da Proteína Quinase Ativada por Mitógeno/genética , Fosfatases da Proteína Quinase Ativada por Mitógeno/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo
4.
Hepatology ; 78(1): 167-178, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-36724876

RESUMO

In cases of end-stage liver diseases, the proliferation of existing hepatocytes is compromised, a feature of human chronic liver disease, in which most hepatocytes are dysfunctional. So far, liver transplantation represents the only curative therapeutic solution for advanced liver diseases, and the shortage of donor organs leads to high morbidity and mortality worldwide. The promising treatment is to prompt the biliary epithelial cells (BECs) transdifferentiation. However, the critical factors governing the initiation of BEC-derived liver regeneration are largely unknown. The zebrafish has advantages in large-scale genetic screens to identify the critical factors involved in liver regeneration. Here, we combined N-ethyl-N-nitrosourea screen, positional cloning, transgenic lines, antibody staining, and in situ hybridization methods and identified a liver regeneration defect mutant ( lrd ) using the zebrafish extensive liver injury model. Through positional cloning and genomic sequencing, we mapped the mutation site to rngtt . Loss of rngtt leads to the defects of BEC dedifferentiation, bipotential progenitor cell activation, and cell proliferation in the initiation stage of liver regeneration. The transdifferentiation from BECs to hepatocytes did not occur even at the late stage of liver regeneration. Mechanically, Rngtt transcriptionally regulates the attachment of mRNA cap to mTOR complex 1 (mTORC1) components and dnmt1 to maintain the activation of mTORC1 and DNA methylation in BECs after severe liver injury and prompt BEC to hepatocyte conversion. Furthermore, rptor and dnmt1 mutants displayed the same liver regeneration defects as rngtt mutation. In conclusion, our results suggest Rngtt is a new factor that initiates BEC-derived liver regeneration.


Assuntos
Regeneração Hepática , Peixe-Zebra , Animais , Humanos , DNA (Citosina-5-)-Metiltransferase 1 , Células Epiteliais , Hepatócitos/fisiologia , Fígado , Regeneração Hepática/genética , Alvo Mecanístico do Complexo 1 de Rapamicina , Proteínas de Peixe-Zebra/genética
5.
Inorg Chem ; 63(31): 14345-14353, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39033409

RESUMO

A biocompatible metal-organic framework (MOF), named HSTC-4, constructed using the flexible 4,4'-oxybis(benzoic acid) (OBA), was developed to enable efficient loading and controlled release of vitamin C (VC) through a combination of strategies involving ligand length, structure design, and metal selection. The kinetic product HSTC-4 demonstrates a propensity for transforming into the thermodynamically stable HSTC-5 under external stimuli, such as photoillumination and vacuum heating, as witnessed by single-crystal to single-crystal transformation. Density functional theory (DFT) calculations reveal that the VC guest molecules exhibit stronger binding affinity with HSTC-5 due to its narrower pores compared to HSTC-4, resulting in a slower release of VC from VC@HSTC-5. Furthermore, precise control over VC release can be achieved by introducing surface modifications involving SiO2 onto the structure of VC@HSCT-5, while simultaneously adjusting environmental factors such as pH and temperature conditions. Preliminary cell culture experiments and cytotoxicity assays highlight the biocompatibility of HSTC-5, suggesting that it is a promising platform for sustained drug delivery and diverse biomedical applications.


Assuntos
Ácido Ascórbico , Estruturas Metalorgânicas , Termodinâmica , Estruturas Metalorgânicas/química , Estruturas Metalorgânicas/farmacologia , Ácido Ascórbico/química , Cinética , Humanos , Teoria da Densidade Funcional , Sobrevivência Celular/efeitos dos fármacos , Portadores de Fármacos/química , Estrutura Molecular , Liberação Controlada de Fármacos
6.
Anal Bioanal Chem ; 416(14): 3305-3312, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38642098

RESUMO

Metformin (MET) and sitagliptin (STG) are widely used as the first-line and long-term oral hypoglycemic agents for managing type 2 diabetes mellitus (T2DM). However, the current lack of convenient and rapid measurement methods poses a challenge for individualized management. This study developed a point-of-care (POC) assay method utilizing a miniature mass spectrometer, enabling rapid and accurate quantification of MET and STG concentrations in human blood and urine. By combining the miniature mass spectrometer with paper spray ionization, this method simplifies the process into three to four steps, requires minimal amounts of bodily fluids (50 µL of blood and 2 µL of urine), and is able to obtain quantification results within approximately 2 min. Stable isotope-labeled internal standards were employed to enhance the accuracy and stability of measurement. The MS/MS responses exhibited good linear relationship with concentration, with relative standard deviations (RSDs) below 25%. It has the potential to provide immediate treatment feedback and decision support for patients and healthcare professionals in clinical practice.


Assuntos
Hipoglicemiantes , Metformina , Sistemas Automatizados de Assistência Junto ao Leito , Fosfato de Sitagliptina , Humanos , Fosfato de Sitagliptina/sangue , Fosfato de Sitagliptina/urina , Metformina/sangue , Metformina/urina , Hipoglicemiantes/urina , Hipoglicemiantes/sangue , Limite de Detecção , Espectrometria de Massas em Tandem/métodos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/urina , Espectrometria de Massas/métodos , Reprodutibilidade dos Testes
7.
Carcinogenesis ; 44(1): 93-104, 2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-36349938

RESUMO

The p38 MAP kinase (MAPK) signaling pathway is a key signal transduction cascade that cancer cells employ to sense and adapt to a plethora of environmental stimuli and has attracted much attention as a promising target for cancer therapy. Although the kinases that phosphorylate p38 have been extensively studied, the negative regulation of p38 phosphorylation remains to be elucidated. Here, we found that PPM1G was highly expressed in lung adenocarcinoma (LUAD) compared to normal tissues, and higher levels of PPM1G were observed in adverse staged LUAD. Furthermore, the higher levels of PPM1G were highly correlated with poor prognosis, according to the Cancer Genome Atlas cohort. Most importantly, we identified phospho-MEK6 as a direct substrate of PPM1G. PPM1G, a metal-dependent protein phosphatase family phosphatase, could reduce p38 phosphorylation via MEK6 dephosphorylation and contribute to the proliferation, invasion and metastasis of LUAD. Our study highlighted the essential role of PPM1G in LUAD and shed new light on unveiling the regulation of p38 activity via direct dephosphorylation of MEK6 in malignant transformation. Together, this study provides new insight into the complexity of regulating the versatile p38 signaling and suggests new directions in intervening in p38 MAPK signaling.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Humanos , Fosforilação/fisiologia , Transdução de Sinais , Fosfoproteínas Fosfatases/genética , Adenocarcinoma de Pulmão/genética , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Neoplasias Pulmonares/genética , Linhagem Celular Tumoral , Proliferação de Células , Proteína Fosfatase 2C/genética , Proteína Fosfatase 2C/metabolismo
8.
Zhongguo Zhong Yao Za Zhi ; 48(1): 45-51, 2023 Jan.
Artigo em Zh | MEDLINE | ID: mdl-36725257

RESUMO

Violet root rot is one of the main root diseases in the production process of Pseudostellaria heterophylla. To clarify the pathogenic species that cause the violet root rot of P. heterophylla in Fujian province, the roots and the sclerotia with violet root rot symptoms were collected from the main producing areas of P. heterophylla(Fujian province) from 2017 to 2021, and the pathogens were isolated by tissue separation method and identified by morphology and multi-gene phylogenetic analysis. Additionally, the biological characteristics of the pathogens were studied and the fungicides were determined. The results showed that 78 strains of violet root rot were isolated from the collected root samples, which belonged to one type after preliminary morphological identification. Two represen-tative strains were selected from the pathogens for multi-gene phylogenetic analysis, and they were clustered with Helicobasidium mompa together. The suitable culture conditions for the mycelium were OA medium, 25 ℃, pH 6, and ammonium oxalate as the nitrogen source. The lethal temperature of the mycelium was 50 ℃ for 10 minutes. Moreover, 99.1% propiconazole and 98.7% azoxystrobin had the optimal bacteriostatic effect, and the concentrations with the 50% bacteriostatic rate were 16.85 and 12.24 µg·mL~(-1), respectively. On the basis of the above results, the pathogen causing violet root rot of P. heterophylla in Fujian province was H. mompa. The medium type, growth temperature, pH value, nitrogen source, etc. had significant effect on the growth of mycelium.


Assuntos
Caryophyllaceae , Raízes de Plantas , Filogenia , Temperatura , Nitrogênio
9.
Zhongguo Zhong Yao Za Zhi ; 48(10): 2732-2738, 2023 May.
Artigo em Zh | MEDLINE | ID: mdl-37282933

RESUMO

In Zherong county, Fujian province, the black spot of Pseudostellaria heterophylla often breaks out in the rainy season from April to June every year. As one of the main leaf diseases of P. heterophylla, black spot seriously affects the yield and quality of the medicinal material. To identify and characterize the pathogens causing black spot, we isolated the pathogens, identified them as a species of Alternaria according to Koch's postulates, and then tested their pathogenicity and biological characteristics. The results showed that the pathogens causing P. heterophylla black spot were A. gaisen, as evidenced by the similar colony morphology, spore characteristics, sporulation phenotype, and the same clade with A. gaisen on the phylogenetic tree(the maximum likelihood support rate of 100% and the Bayesian posterior probability of 1.00) built based on the tandem sequences of ITS, tef1, gapdh, endoPG, Alta1, OPA10-2, and KOG1077. The optimum conditions for mycelial growth of the pathogen were 25 ℃, pH 5-8, and 24 h dark culture. The lethal conditions for mycelia and spores were both treatment at 50 ℃ for 10 min. We reported for the first time the A. gaisen-caused black spot of P. heterophylla. The results could provide a theoretical basis for the diagnosis and control of P. heterophylla leaf spot diseases.


Assuntos
Alternaria , Caryophyllaceae , Doenças das Plantas , Alternaria/classificação , Alternaria/genética , Alternaria/crescimento & desenvolvimento , Alternaria/patogenicidade , Caryophyllaceae/microbiologia , DNA Fúngico/genética , Micélio/crescimento & desenvolvimento , Filogenia , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , China
10.
Ecotoxicol Environ Saf ; 238: 113620, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35561544

RESUMO

Sulfamethoxazole (SMX) is a widespread broad-spectrum bacteriostatic antibiotic. Its residual is frequently detected in the water and may therefore bioaccumulate in the brain of aquatic organisms via blood circulation. Brain capillaries toxicity is very important for brain development. However, little information is available in the literature to show the toxicity of SMX to brain development. To study the SMX's brain toxic effects and the related mechanisms, we exposed zebrafish embryos to SMX at different concentrations (0 ppm, 1 ppm, 25 ppm, 100 ppm and 250 ppm) and found that high concentration (250 ppm) of SMX would not only caused an abnormal in malformation rate, hatching rate, body length and survival rate of zebrafish embryos, but also lead to brain oedema. In addition, SMX also induced cerebral ischaemia, aggravates oxidative stress, and changes genes related to oxidative stress (sod1, cat, gpx4, and nrf2). Furthermore, ischaemia caused by SMX could promote ectopic angiogenesis in brain via activating the angiogenesis-related genes (vegfab, cxcr4a, cxcl12b) from 24 h to 53 h. Inhibition of VEGF signalling by SU5416, or inhibition of chemokine downstream PI3K signalling by LY294002, could rescue the brain capillaries toxicity and brain oedema induced by SMX. Our results provide new evidence for the brain toxicity of SMX and its residual danger in the environment and aquatic organisms.


Assuntos
Edema Encefálico , Poluentes Químicos da Água , Animais , Organismos Aquáticos , Encéfalo , Edema Encefálico/induzido quimicamente , Capilares , Sulfametoxazol/toxicidade , Regulação para Cima , Fator A de Crescimento do Endotélio Vascular/genética , Poluentes Químicos da Água/toxicidade , Peixe-Zebra
11.
Chem Biodivers ; 19(11): e202200117, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36165268

RESUMO

Photodynamic therapy (PDT), which uses targeted photosensitizing drugs, has been regarded as a promising method for cancer therapy. In the present study, photosensitizer red phosphorus modified P25 nanophotosensitizers (P25-RP) were generated, which were coated with platelet membrane (P25-RP@PLT) extracted from platelet rich plasma. The biocompatibility of P25-RP was demonstrated by cell counting kit-8 (CCK-8) and optical microscope assay, more than 93 % cells in the concentration of 100 µg/ml of P25-RP suspension after co-incubation for 24 h were still kept alive. The antitumor performance of P25-RP@PLT was evaluated via CCK-8 assay, flow cytometry and fluorescence staining of live/dead cells. The experiment results showed that P25-RP@PLT could ablate 55 % malignant tumor cells upon laser irradiation within 5 min, which was 10 % higher than P25-RP alone against cancer cells. Mechanistically, the cancer cell toxicity of P25-RP@PLT nanophotosensitizers was attributed to its heterojunction structure that broadens the absorption spectra, whereas PLT membrane coating technology allows for immune escape and selective adhesion capacity to cancer cells. This work provided a novel pathway on the design of novel visible-light-driven photosensitizer for cancer therapy.


Assuntos
Neoplasias , Fotoquimioterapia , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/química , Fósforo , Linhagem Celular Tumoral , Neoplasias/tratamento farmacológico
12.
Water Sci Technol ; 86(7): 1719-1732, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36240307

RESUMO

The application of membrane technology in the field of water treatment was increasingly widespread, but membrane fouling still restricted its development, and the membrane needed to be chemically cleaned. This research focused on the high-efficiency pickling technology of ceramic membrane, and developed the cleaning technology of ceramic membrane in cooperation with surfactant. In the experiment, the municipal secondary effluent was used as the raw water, and the single-step, mixed and step-by-step cleaning effects of three strong acids, three weak acids and surfactants on ceramic membranes and polyvinylidene difluoride (PVDF) membranes were investigated. For ceramic membrane, the optimal cleaning combination was H2SO4 first and then DTAC, and the flux recovery rate could reach 96.94%; for PVDF membrane, the optimal cleaning combination was HNO3 first and then H2SO4, and the flux recovery rate could reach 93.72%. In addition, the surface of initial, polluted, and cleaned membranes were analyzed by scanning electron microscope and contact angle, and the fouling mechanism of the ceramic membrane was analyzed. The results showed that through physical cleaning and chemical cleaning, most of the pollutants on the membrane surface and pores were removed. The cleaning method can effectively control the membrane pollution.


Assuntos
Poluentes Ambientais , Purificação da Água , Cerâmica , Polímeros de Fluorcarboneto , Membranas Artificiais , Polivinil , Tensoativos , Tecnologia , Purificação da Água/métodos
13.
Sensors (Basel) ; 21(5)2021 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-33800750

RESUMO

Mainstream methods treat head pose estimation as a supervised classification/regression problem, whose performance heavily depends on the accuracy of ground-truth labels of training data. However, it is rather difficult to obtain accurate head pose labels in practice, due to the lack of effective equipment and reasonable approaches for head pose labeling. In this paper, we propose a method which does not need to be trained with head pose labels, but matches the keypoints between a reconstructed 3D face model and the 2D input image, for head pose estimation. The proposed head pose estimation method consists of two components: the 3D face reconstruction and the 3D-2D matching keypoints. At the 3D face reconstruction phase, a personalized 3D face model is reconstructed from the input head image using convolutional neural networks, which are jointly optimized by an asymmetric Euclidean loss and a keypoint loss. At the 3D-2D keypoints matching phase, an iterative optimization algorithm is proposed to match the keypoints between the reconstructed 3D face model and the 2D input image efficiently under the constraint of perspective transformation. The proposed method is extensively evaluated on five widely used head pose estimation datasets, including Pointing'04, BIWI, AFLW2000, Multi-PIE, and Pandora. The experimental results demonstrate that the proposed method achieves excellent cross-dataset performance and surpasses most of the existing state-of-the-art approaches, with average MAEs of 4.78∘ on Pointing'04, 6.83∘ on BIWI, 7.05∘ on AFLW2000, 5.47∘ on Multi-PIE, and 5.06∘ on Pandora, although the model of the proposed method is not trained on any of these five datasets.

14.
Sensors (Basel) ; 21(6)2021 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-33807088

RESUMO

Facial expression recognition (FER) is a challenging problem due to the intra-class variation caused by subject identities. In this paper, a self-difference convolutional network (SD-CNN) is proposed to address the intra-class variation issue in FER. First, the SD-CNN uses a conditional generative adversarial network to generate the six typical facial expressions for the same subject in the testing image. Second, six compact and light-weighted difference-based CNNs, called DiffNets, are designed for classifying facial expressions. Each DiffNet extracts a pair of deep features from the testing image and one of the six synthesized expression images, and compares the difference between the deep feature pair. In this way, any potential facial expression in the testing image has an opportunity to be compared with the synthesized "Self"-an image of the same subject with the same facial expression as the testing image. As most of the self-difference features of the images with the same facial expression gather tightly in the feature space, the intra-class variation issue is significantly alleviated. The proposed SD-CNN is extensively evaluated on two widely-used facial expression datasets: CK+ and Oulu-CASIA. Experimental results demonstrate that the SD-CNN achieves state-of-the-art performance with accuracies of 99.7% on CK+ and 91.3% on Oulu-CASIA, respectively. Moreover, the model size of the online processing part of the SD-CNN is only 9.54 MB (1.59 MB ×6), which enables the SD-CNN to run on low-cost hardware.


Assuntos
Reconhecimento Facial , Expressão Facial , Redes Neurais de Computação
15.
Hepatology ; 70(6): 2092-2106, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31136010

RESUMO

The liver has a high regenerative capacity. Upon two-thirds partial hepatectomy, the hepatocytes proliferate and contribute to liver regeneration. After severe liver injury, when the proliferation of residual hepatocytes is blocked, the biliary epithelial cells (BECs) lose their morphology and express hepatoblast and endoderm markers, dedifferentiate into bipotential progenitor cells (BP-PCs), then proliferate and redifferentiate into mature hepatocytes. Little is known about the mechanisms involved in the formation of BP-PCs after extreme liver injury. Using a zebrafish liver extreme injury model, we found that mammalian target of rapamycin complex 1 (mTORC1) signaling regulated dedifferentiation of BECs and proliferation of BP-PCs. mTORC1 signaling was up-regulated in BECs during extreme hepatocyte ablation and continuously expressed in later liver regeneration. Inhibition of mTORC1 by early chemical treatment before hepatocyte ablation blocked the dedifferentiation from BECs into BP-PCs. Late mTORC1 inhibition after liver injury reduced the proliferation of BP-PC-derived hepatocytes and BECs but did not affect BP-PC redifferentiation. mTOR and raptor mutants exhibited defects in BEC transdifferentiation including dedifferentiation, BP-PC proliferation, and redifferentiation, similar to the chemical inhibition. Conclusion: mTORC1 signaling governs BEC-driven liver regeneration by regulating the dedifferentiation of BECs and the proliferation of BP-PC-derived hepatocytes and BECs.


Assuntos
Sistema Biliar/citologia , Desdiferenciação Celular , Regeneração Hepática/fisiologia , Alvo Mecanístico do Complexo 1 de Rapamicina/fisiologia , Células-Tronco/citologia , Animais , Apoptose , Proliferação de Células , Células Epiteliais/citologia , Alvo Mecanístico do Complexo 1 de Rapamicina/antagonistas & inibidores , Proteínas Nucleares/fisiologia , Transdução de Sinais/fisiologia , Sirolimo/farmacologia , Peixe-Zebra , Proteínas de Peixe-Zebra/fisiologia
16.
World J Surg Oncol ; 18(1): 85, 2020 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-32359372

RESUMO

BACKGROUND: Peritoneal leiomyomatosis disseminate (LPD) is a rare disease characterized by widespread dissemination of leiomyomas nodules throughout the peritoneal and omental surfaces. Reports of pregnancy with LPD are even rarer. Therefore, there is no clear consensus on the treatment of LPD on pregnancy, and the pathogenesis is still unclear. CASE PRESENTATION: We reported a case of LPD patient who developed during pregnancy. The patient underwent a cesarean section at 32 weeks of gestation while removing all visible tumors, and no LPD lesions were seen in the subsequent cesarean section at full term. NGS of LPD lesions detected 4 mutations with focal high-level amplifications of CDK4 (cyclin-dependent kinases 4), NBN (Nibrin), DAXX (death domain associated protein), and MYC (myelocytomatosis oncogene). Immunohistochemistry staining analysis among benign leiomyoma, LPD, and leiomyosarcoma verified that LPD was an unusual intermediate between benign and malignant uterine smooth muscle tumors. Besides, LPD is a hormonal-dependent leiomyoma. After a detailed literature search, we summarized the detailed clinical features and follow-up information of patients with LPD during pregnancy. CONCLUSIONS: This is the first reported LPD case of successful term pregnancy without recurrence, following resection of all visible lesions in a prior pregnancy. LPD is an unusual intermediate between benign and malignant uterine smooth muscle tumors.


Assuntos
Biomarcadores Tumorais/genética , Leiomiomatose/cirurgia , Neoplasias Peritoneais/cirurgia , Complicações na Gravidez/cirurgia , Neoplasias Uterinas/cirurgia , Adulto , Proteínas de Ciclo Celular/genética , Cesárea , Proteínas Correpressoras/genética , Quinase 4 Dependente de Ciclina/genética , Análise Mutacional de DNA , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Leiomiomatose/diagnóstico , Leiomiomatose/genética , Imageamento por Ressonância Magnética , Chaperonas Moleculares/genética , Mutação , Proteínas Nucleares/genética , Neoplasias Peritoneais/diagnóstico , Neoplasias Peritoneais/genética , Neoplasias Peritoneais/secundário , Gravidez , Complicações na Gravidez/diagnóstico , Complicações na Gravidez/patologia , Proteínas Proto-Oncogênicas c-myc/genética , Resultado do Tratamento , Neoplasias Uterinas/diagnóstico , Neoplasias Uterinas/genética , Neoplasias Uterinas/patologia
17.
J Obstet Gynaecol Res ; 45(11): 2267-2274, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31411802

RESUMO

AIM: Subjects with germline BRCA1/2 mutations (gBRCAm) have an increased risk of developing breast cancer and ovarian cancer. At present, knowledge of BRCA1/2 mutation frequency in Chinese patients with ovarian cancer is still insufficient, and the detailed clinical information of these patients is poorly understood. METHODS: A total of 547 unselected ovarian cancer patients were enrolled, and their gBRCAm status was detected. Clinical characteristics including age, personal and family history, histopathologic diagnosis, carbohydrate antigen 125 (CA-125) level, ascites, Federation International of Gynecology and Obstetrics (FIGO) stage, residual lesions, platinum sensitivity, recurrence interval and survival information were collected. Accurate assessments of disease response were based on the RECIST standard or CA-125 level. RESULTS: In 547 patients with ovarian cancer, we detected 129 (23.6%) patients with pathogenic mutations, 84 patients with BRCA1 mutations (15.4%) and 45 patients with BRCA2 mutations (8.2%). Twenty-five novel mutations were identified, and the mutation of BRCA1, c.5470_5477del8, was the most common mutation in this study. BRCA1/2 mutations were significantly associated with age; personal and family history; FIGO stage; secondary recurrence interval; sensitivity to platinum in 1st, 2nd and 3rd line treatment; and response to doxorubicin liposomes. Patients with BRCA1/2 mutations showed significant advantages in 3- and 5-year survival rates but no advantage in long-term survival. CONCLUSION: BRCA1/2 mutation prevalence in Chinese ovarian cancer patients is higher than the international rate. We recommend BRCA1/2 testing for patients with family histories and personal histories of malignancy and genetic counseling for cancer in healthy people with high-risk family histories.


Assuntos
Povo Asiático/genética , Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias Ovarianas/genética , Adulto , Idoso , Antígeno Ca-125/análise , China/epidemiologia , Feminino , Humanos , Pessoa de Meia-Idade , Taxa de Mutação , Neoplasias Ovarianas/epidemiologia , Neoplasias Ovarianas/patologia , Prevalência
18.
J Cell Mol Med ; 22(6): 3259-3263, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29575613

RESUMO

Single-chain variable fragment (scFv) antibodies are the smallest immunoglobulins with high antigen-binding affinity. We have previously reported that fibroblast growth factor 1 played pivotal roles in cancer development and generated a mouse scFv (mscFv1C9) could effectively prohibit cancer cell proliferation in vitro and in vivo. Here, we further humanized this scFv (hscFv1C9) using a structure-guided complementarity determining region grafting strategy. The purified hscFv1C9 maintained similar antigen-binding affinity and specificity as mscFv1C9, and it was capable of inhibiting growth of different tumours in vitro and in vivo. These data strongly suggested that hscFv1C9 has antitumour potentials.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Fator 1 de Crescimento de Fibroblastos/antagonistas & inibidores , Glioma/tratamento farmacológico , Anticorpos de Cadeia Única/farmacologia , Sequência de Aminoácidos/genética , Animais , Anticorpos Monoclonais Humanizados/imunologia , Anticorpos Monoclonais Humanizados/farmacologia , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ensaio de Imunoadsorção Enzimática , Feminino , Fator 1 de Crescimento de Fibroblastos/química , Fator 1 de Crescimento de Fibroblastos/genética , Fator 1 de Crescimento de Fibroblastos/imunologia , Glioma/genética , Glioma/patologia , Xenoenxertos , Humanos , Camundongos , Anticorpos de Cadeia Única/imunologia
19.
J Asthma ; 55(10): 1079-1085, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29611766

RESUMO

BACKGROUND: The pathogenesis of asthma is complex and continues to be considered as a challenging subject. Some studies have shown that nerve growth factor (NGF) participates in the pathogenesis of asthma, but the mechanism of airway contraction caused by NGF is still unclear. OBJECTIVE: Our aim was to discuss the effect of anti-NGF antibody on RhoA expression, and further explore the role of NGF in airway hyperresponsiveness (AHR). METHODS: Thirty female BALB/c mice were divided into three groups randomly: control group (group C, n = 10), asthma group (group A, n = 10) and anti-NGF antibody intervention group (group N, n = 10). The asthmatic mice were stimulated by OVA suspension, the intervention mice were given nasal instillation of anti-NGF antibody before the stimulation. Airway responsiveness, eosinophils, IL-13, IFN-γ were measured. The protein expression and mRNA level of NGF and RhoA were detected by immunohistochemical and Real Time-PCR (RT-PCR) analyses. RESULTS: Airway responsiveness, eosinophils and IL-13 levels in group A were significantly increased compare with the other groups, and significantly decreased in group N than those in group A. IFN-γ level was significantly reduced in group A and increased in group N. Immunohistochemistry and RT-PCR analyses showed that the protein expression and mRNA level of NGF and RhoA were significantly increased in group A and significantly decreased in group N. CONCLUSION: NGF participates in the pathogenesis of asthma in mice. Anti-NGF antibody can inhibit airway inflammation and alleviate AHR by down-regulating the protein expression and mRNA level of RhoA.


Assuntos
Fator de Crescimento Neural/imunologia , Hipersensibilidade Respiratória/imunologia , Proteína rhoA de Ligação ao GTP/biossíntese , Animais , Modelos Animais de Doenças , Eosinófilos/imunologia , Feminino , Imuno-Histoquímica , Inflamação/imunologia , Interferon gama/biossíntese , Interleucina-13/biossíntese , Pulmão/patologia , Camundongos , Camundongos Endogâmicos BALB C , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais/fisiologia
20.
Zhonghua Fu Chan Ke Za Zhi ; 51(1): 40-5, 2016 Jan.
Artigo em Zh | MEDLINE | ID: mdl-26899006

RESUMO

OBJECTIVE: To detect and explore the expression and clinical significance of dual specificity tyrosine phosphorylation regulated kinase1b (Dyrk1b) in the specimens and cells of cervical lesions. METHODS: (1) All the data were collected from 75 patients with cervical cancer and 52 cases with squamous intraepithelial lesion (SIL) admitted in the First Affiliated Hospital of Dalian Medical College during Jan. 2011 to Dec. 2013 and confirmed by pathological examination, included 60 cases of stage Ⅰ and 15 cases of stage Ⅱ, 12 cases with low-grade squamous intraepithelial lesion (LSIL) and 40 cases with high-grade squamous intraepithelial lesion (HSIL). While, 28 cases with chronic cervicitis were chosen as the control group. The protein expression of Dyrk1b was detected by immunohistochemistry among the four groups. (2) The expression of Dyrk1b in HeLa and SiHa cells were detected by western blot method and the expression of Dyrk1b protein were also detected after treatment of AZ191 (5, 10 µmol/L) for 48 hours in HeLa and SiHa cells. (3) The cellular survival and proliferation of HeLa and SiHa cells treated by different concentrations of AZ191 (2.5, 5, 10, 25, 50, 100 µmol/L) for 48 hours were detected by methyl thiazolyl tetrazolium (MTT) assay. (4) The rate of apoptosis of HeLa and SiHa cells was detected by flowcytometry after treatment of AZ191 (5, 10 µmol/L) for 48 hours. RESULTS: (1) The positive rates of Dyrk1b protein in chronic cervicitis, LSIL, HSIL and cervical squamous cancer by immunohistochemistry were 11%(3/28), 1/12, 42% (17/40) and 71% (53/75), respectively. The expression of Dyrk1b in cervical squamous cancer and HISL were higher than those in LSIL and chronic cervicitis (P<0.01), there were significant difference between cervical squamous cancer and HSIL, or between HSIL and LSIL (all P<0.05), while there were not significant difference between LSIL and chronic cervicitis (P>0.05). Expression of Dyrk1b was correlated with stromal invasion depth of cervical cancer (P<0.05), but not with age, clinical stage, lymph node metastasis, and serum squamous cell carcinom antigen (SCC-Ag) levels (all P>0.05). (2) Dyrk1b protein was expressed in different levels in HeLa and SiHa cells, and the expression of Dyrk1b was decreased gradually as the increased of the concentration of AZ191 in both HeLa and SiHa cells by treatment of AZ191 for 48 hours. (3) Different concentration of AZ191 treated on cervical cancer cells could inhibit the cellular proliferation and induce cell apoptosis in a concentration-dependent manner (P<0.01), concomitant to the decreased cell survival rate. The apoptosis rate of HeLa and SiHa were increased significantly after 10 µmol/L AZ191-treatment for 48 hours, but no any difference induced by 5 µmol/L AZ191-treatment compared to control group. Also,there was no any difference between Hela and SiHa cells in either inhibitory effect or apoptosis rate induced by AZ191. CONCLUSIONS: Dyrk1b is over-expressed in either specimens or cells of cervical cancer. The expression of Dyrk1b protein in cervical lesions is increased as the progression of disease. Dyrk1b inhibitor AZ191 could inhibit cellular proliferation and induce apoptosis in a concentration-dependent manner in cervical cancer cells.


Assuntos
Carcinoma de Células Escamosas/patologia , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Tirosina Quinases/metabolismo , Lesões Intraepiteliais Escamosas Cervicais/patologia , Displasia do Colo do Útero/patologia , Neoplasias do Colo do Útero/patologia , Apoptose , Western Blotting , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Proliferação de Células , Feminino , Regulação Neoplásica da Expressão Gênica , Células HeLa , Humanos , Imuno-Histoquímica , Metástase Linfática , Lesões Intraepiteliais Escamosas Cervicais/genética , Lesões Intraepiteliais Escamosas Cervicais/metabolismo , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/metabolismo , Displasia do Colo do Útero/genética , Displasia do Colo do Útero/metabolismo , Quinases Dyrk
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