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1.
J Gene Med ; 26(1): e3632, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38282151

RESUMO

BACKGROUND: Ribosome biogenesis protein BRX1 homolog (BRIX1) is critically required for the synthesis of the 60S ribosome subunit. However, the role and mechanism of BRIX1 in colorectal cancer (CRC) remain unclear. METHODS: Kyoto Encyclopedia of Gene and Genome pathway and Gene Ontology analyses were used for bioinformatics analysis. The rRNA levels were detected in CRC tissues and cells. Nascent RNA synthesis was detected via cellular immunofluorescence. The correlation was analyzed between patient Positron Emission Tomography-Computed Tomography (PET-CT) values and their BRIX1 expression. The extracellular acidification rate (ECAR) and oxygen consumption rate were determined via live metabolic analyses. Polysome fractions were collected for BRIX1 mRNA used in translation. The orthotopic model and Cell Counting Kit-8 (CCK8) assay were used to assess BRIX1 function in CRC. RESULTS: BRIX1 is a core protein involved in ribosome-related pathway changes in CRC. Gene Ontology analysis showed that BRIX1 was primarily enriched in ribosome assembly and ribosome biogenesis pathways. In fresh CRC tissue, rRNA levels (5S, 5.8S, 18S and 28S) were higher in the BRIX1 high-expression group than in the BRIX1 low-expression group. Similarly, BRIX1 knockdown significantly decreased rRNA levels for 5S, 5.8S, 18S and 28S in CRC cells, whereas overexpression of BRIX1 significantly increased these levels. In addition, BRIX1 knockdown inhibited nascent RNA synthesis in CRC cells. In clinical data analysis, BRIX1 expression was related to the glucose uptake in PET-CT. BRIX1 knockdown significantly decreased the ECAR value, glucose uptake and lactic acid production in CRC cells, whereas BRIX1 overexpression significantly increased these. Furthermore, BRIX1 knockdown significantly decreased the protein expression of GLUT1, whereas BRIX1 overexpression significantly increased this; however, expression of BRIX1 mRNA was unaffected in either case. Blocking glycolysis by si-GLUT1 or galactose reversed BRIX1 promotion of glycolysis and cell proliferation in CRC cells.


Assuntos
Neoplasias Colorretais , Transportador de Glucose Tipo 1 , Proteínas Nucleares , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Humanos , Proliferação de Células/genética , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Glucose/metabolismo , Glicólise , Ribossomos/genética , Ribossomos/metabolismo , RNA Mensageiro/metabolismo , Proteínas Nucleares/genética
2.
N Engl J Med ; 389(18): 1649-1659, 2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37913505

RESUMO

BACKGROUND: Recurrent bleeding from the small intestine accounts for 5 to 10% of cases of gastrointestinal bleeding and remains a therapeutic challenge. Thalidomide has been evaluated for the treatment of recurrent bleeding due to small-intestinal angiodysplasia (SIA), but confirmatory trials are lacking. METHODS: We conducted a multicenter, double-blind, randomized, placebo-controlled trial to investigate the efficacy and safety of thalidomide for the treatment of recurrent bleeding due to SIA. Eligible patients with recurrent bleeding (at least four episodes of bleeding during the previous year) due to SIA were randomly assigned to receive thalidomide at an oral daily dose of 100 mg or 50 mg or placebo for 4 months. Patients were followed for at least 1 year after the end of the 4-month treatment period. The primary end point was effective response, which was defined as a reduction of at least 50% in the number of bleeding episodes that occurred during the year after the end of thalidomide treatment as compared with the number that occurred during the year before treatment. Key secondary end points were cessation of bleeding without rebleeding, blood transfusion, hospitalization because of bleeding, duration of bleeding, and hemoglobin levels. RESULTS: Overall, 150 patients underwent randomization: 51 to the 100-mg thalidomide group, 49 to the 50-mg thalidomide group, and 50 to the placebo group. The percentages of patients with an effective response in the 100-mg thalidomide group, 50-mg thalidomide group, and placebo group were 68.6%, 51.0%, and 16.0%, respectively (P<0.001 for simultaneous comparison across the three groups). The results of the analyses of the secondary end points supported those of the primary end point. Adverse events were more common in the thalidomide groups than in the placebo group overall; specific events included constipation, somnolence, limb numbness, peripheral edema, dizziness, and elevated liver-enzyme levels. CONCLUSIONS: In this placebo-controlled trial, treatment with thalidomide resulted in a reduction in bleeding in patients with recurrent bleeding due to SIA. (Funded by the National Natural Science Foundation of China and the Shanghai Municipal Education Commission, Gaofeng Clinical Medicine; ClinicalTrials.gov number, NCT02707484.).


Assuntos
Angiodisplasia , Hemorragia Gastrointestinal , Fármacos Hematológicos , Enteropatias , Intestino Delgado , Talidomida , Humanos , Angiodisplasia/complicações , Angiodisplasia/tratamento farmacológico , China , Método Duplo-Cego , Hemorragia Gastrointestinal/tratamento farmacológico , Hemorragia Gastrointestinal/etiologia , Talidomida/administração & dosagem , Talidomida/efeitos adversos , Talidomida/uso terapêutico , Resultado do Tratamento , Enteropatias/complicações , Enteropatias/tratamento farmacológico , Recidiva , Intestino Delgado/irrigação sanguínea , Administração Oral , Fármacos Hematológicos/administração & dosagem , Fármacos Hematológicos/efeitos adversos , Fármacos Hematológicos/uso terapêutico
3.
J Clin Pathol ; 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-37989553

RESUMO

AIMS: Operative link on gastritis assessment (OLGA) and operative link on gastric intestinal metaplasia assessment (OLGIM) systems are histological staging systems of gastritis for gastric cancer (GC) risk estimation. Intermediate OLGA/OLGIM stages are of concern in a region with high incidence of GC. This study aimed to validate OLGA and OLGIM staging systems for early GC (EGC) in Chinese population. METHODS: This single-centre, case-control study included 196 patients with EGC and 196 age-matched and sex-matched health screening control subjects. OLGA and OLGIM systems, and other clinical parameters were evaluated using logistic regression analysis. RESULTS: OLGA and OLGIM stages II/III/IV were more prevalent in patients with EGC than in the control subjects. Multivariable analysis revealed family history of GC, previous Helicobacter pylori (H. pylori) infection, OLGA stages II and III-IV, OLGIM stages II and III-IV as independent risk factors for EGC (ORs, 4.04, 1.87, 2.52, 6.79, 4.11 and 10.78, respectively). Area under the receiver operating characteristic curve on EGC risk estimation was improved for OLGIM compared with OLGA (0.78 vs 0.71, p<0.001). Autoantibody seropositivity of gastric mucosa was not associated with EGC risk stratified by H. pylori status. CONCLUSIONS: Surveillance of intermediate-risk patients (OLGA/OLGIM II) should be emphasised in our region. The OLGIM may be preferred over the OLGA for EGC risk estimation.

4.
Cell Biosci ; 13(1): 164, 2023 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-37689735

RESUMO

BACKGROUND: PI3K/AKT signaling pathway plays important role in tumorigenesis of human cancer. Protein phosphorylation is crucial for signaling transduction of this pathway. PIK3CA, encoding the catalytic subunit p110α of PI3K complex, is one of the most frequently mutated oncogenes in human cancers. However, phosphorylation sites of PIK3CA/p110α and their underlying mechanism in tumorigenesis are largely unknown. METHODS: Tyrosine phosphorylation sites of PIK3CA/p110α are identified with Mass-Spectrum. Crispr/CAS9 strategy is applied to generate Y317F and Y508F mutant knock-in cell clones. The growth and metastasis abilities of cells are evaluated in vitro and in vivo. Phospho-proteomics analysis and Western blots are used to demonstrate downstream signaling pathways of PIK3CA/p110α tyrosine phosphorylation. In vitro kinase assay is applied to identify the kinase of PIK3CA/p110α tyrosine phosphorylation. RESULTS: Tyrosine phosphorylation of PIK3CA/p110α is stimulated by growth factors such as EGF, HGF and PDGF. Two tyrosine residues, Y317 and Y508, are identified on PIK3CA/p110α. Either Y317 or Y508 phosphorylation is essential for tumorigenesis of CRC. Mutation at Y317 of p110α reduces the proliferation, migration, and invasion of cancer cells through Src-MLC2 pathway, while mutation at Y508 of p110α impairs AKT signaling. Moreover, Src interacts with and phosphorylates p110α. CONCLUSIONS: PIK3CA/p110α phosphorylation at Y317 and Y508 play important role in tumorigenesis of colorectal cancer through two independent pathways.

5.
Nat Commun ; 14(1): 2042, 2023 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-37041160

RESUMO

Colonocyte metabolism shapes the microbiome. Metabolites are the main mediators of information exchange between intestine and microbial communities. Arachidonic acid (AA) is an essential polyunsaturated fatty acid and its role in colorectal cancer (CRC) remains unexplored. In this study, we show that AA feeding promotes tumor growth in AOM/DSS and intestinal specific Apc-/- mice via modulating the intestinal microecology of increased gram-negative bacteria. Delta-5 desaturase (FADS1), a rate-limiting enzyme, is upregulated in CRC and effectively mediates AA synthesis. Functionally, FADS1 regulates CRC tumor growth via high AA microenvironment-induced enriched gram-negative microbes. Elimination of gram-negative microbe abolishes FADS1 effect. Mechanistically, gram-negative microbes activate TLR4/MYD88 pathway in CRC cells that contributes FADS1-AA axis to metabolize to prostaglandin E2 (PGE2). Cumulatively, we report a potential cancer-promoting mechanism of FADS1-AA axis in CRC that converts raising synthesized AA to PGE2 via modulating the intestinal microecology of gram-negative.


Assuntos
Ácido Araquidônico , Carcinogênese , Neoplasias Colorretais , Ácidos Graxos Dessaturases , Microbioma Gastrointestinal , Bactérias Gram-Negativas , Animais , Camundongos , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/microbiologia , Ácido Araquidônico/metabolismo , Ácidos Graxos Dessaturases/genética , Ácidos Graxos Dessaturases/metabolismo , Células HCT116 , Xenoenxertos , Humanos , Proteína da Polipose Adenomatosa do Colo/genética , Camundongos Mutantes , Camundongos Endogâmicos C57BL , Bactérias Gram-Negativas/metabolismo , Carcinogênese/genética , Carcinogênese/metabolismo , Dinoprostona/metabolismo , Camundongos Endogâmicos BALB C
6.
Oncogene ; 42(2): 99-112, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36376513

RESUMO

The microenvironment of distant organ plays vital roles in regulating tumor metastases. However, little is known about the crosstalk between metastasized tumor cells and target organs. Herein, we found that EFNB2 expression was upregulated in liver metastases (LM) of colorectal cancer (CRC), but not in pulmonary metastases (PM) or primary CRC tumors. EFNB2 played a tumor-promoting role in CRC LM in vitro and in vivo. Through forward signaling, EFNB2-promoted CRC LM by interacting with the EPHB4 receptor. EFNB2/EPHB4 axis enhances LDLR-mediated cholesterol uptake in CRC LM. Subsequently, EFNB2/EPHB4 axis promotes LDLR transcription by regulating STAT3 phosphorylation. Blocking LDLR reversed the role of the EFNB2/EPHB4 axis in promoting CRC LM. Using clinical data, survival analysis revealed that the survival time of patients with CRC LM was decreased in patients with high EFNB2 expression, compared with low EFNB2 expression. Inhibition of the EFNB2/EPHB4 axis markedly prolonged the survival time of BALB/c nude mice with CRC LM with a high cholesterol diet. These findings revealed a key step in the regulation of cholesterol uptake by EFNB2/EPHB4 axis and its tumor-promoting role in CRC LM.


Assuntos
Neoplasias Colorretais , Neoplasias Hepáticas , Animais , Camundongos , Colesterol , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Efrina-B2/metabolismo , Neoplasias Hepáticas/genética , Camundongos Nus , Receptores Proteína Tirosina Quinases , Microambiente Tumoral
7.
Front Psychol ; 13: 941161, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36033069

RESUMO

This paper provides the first meta-analytic examination of the relationship between leadership and followers' intrinsic motivation. In particular, we examined 6 leadership variables (transformational, ethical, leader-member exchange, servant, empowering, and abusive supervision) using data from 50 independent samples and 21,873 participants. We found that transformational leadership, ethical leadership, leader-member exchange (LMX), servant leadership, and empowering leadership were positively related to intrinsic motivation, whereas abusive supervision was negatively linked to intrinsic motivation. Although these leadership styles were associated with intrinsic motivation, they varied considerably in their relative importance. Empowering, ethical, and servant leadership emerged as the more important contributors to intrinsic motivation than transformational leadership. LMX showed a similar contribution with transformational leadership to intrinsic motivation. Effectiveness of leadership styles in relation to intrinsic motivation varied by power distance, publication year, and journal quality. Drawing on our findings, we discuss the theoretical and practice implications.

8.
J Cell Biol ; 221(6)2022 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-35536318

RESUMO

ß-coronaviruses reshape host cell endomembranes to form double-membrane vesicles (DMVs) for genome replication and transcription. Ectopically expressed viral nonstructural proteins nsp3 and nsp4 interact to zipper and bend the ER for DMV biogenesis. Genome-wide screens revealed the autophagy proteins VMP1 and TMEM41B as important host factors for SARS-CoV-2 infection. Here, we demonstrated that DMV biogenesis, induced by virus infection or expression of nsp3/4, is impaired in the VMP1 KO or TMEM41B KO cells. In VMP1 KO cells, the nsp3/4 complex forms normally, but the zippered ER fails to close into DMVs. In TMEM41B KO cells, the nsp3-nsp4 interaction is reduced and DMV formation is suppressed. Thus, VMP1 and TMEM41B function at different steps during DMV formation. VMP1 was shown to regulate cross-membrane phosphatidylserine (PS) distribution. Inhibiting PS synthesis partially rescues the DMV defects in VMP1 KO cells, suggesting that PS participates in DMV formation. We provide molecular insights into the collaboration of host factors with viral proteins to remodel host organelles.


Assuntos
COVID-19 , Proteínas de Membrana , SARS-CoV-2 , Compartimentos de Replicação Viral , Autofagia/genética , Humanos , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Organelas/metabolismo , Fosfatidilserinas , SARS-CoV-2/fisiologia , Proteínas não Estruturais Virais/genética , Replicação Viral
9.
Front Psychol ; 13: 794913, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35282256

RESUMO

Previous studies only considered the impact of personal or environmental factors on intensive smartphone use separately, while largely ignoring the impact of person-environment (P-E) fit on it. Drawing on the P-E fit theory, we proposed that perceived overqualification (POQ), an indicator of person-job misfit, positively affects intensive smartphone use via job boredom, and affective commitment moderates this indirect effect. We examined our hypotheses using four-wave time-lag data of 450 workers from 62 teams. The results revealed that POQ raised job boredom of an individual and thus increased their intensive smartphone use. In addition, when the affective commitment was high, the indirect effect from POQ to intensive smartphone use via job boredom was weaker. The implications, limitations, and future directions of this research were discussed.

10.
Angew Chem Int Ed Engl ; 61(12): e202115812, 2022 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-35064628

RESUMO

The ultralow concentration of nucleic acids in complex biological samples requires fluorescence probes with high specificity and sensitivity. Herein, a new kind of spherical nucleic acids (SNAs) is developed by using fluorescent π-conjugated polymers (FCPs) as a light-harvesting antenna to enhance the signal transduction of nucleic acid detection. Specifically, amphiphilic DNA-grafted FCPs are synthesized and self-assemble into FCP-SNA structures. Tuning the hydrophobicity of the graft copolymer can adjust the size and light-harvesting capability of the FCP-SNAs. We observe that more efficient signal amplification occurs in larger FCP-SNAs, as more chromophores are involved, and the energy transfer can go beyond the Förster radius. Accordingly, the optimized FCP-SNA shows an antenna effect of up to 37-fold signal amplification and the limit of detection down to 1.7 pM in microRNA detection. Consequently, the FCP-SNA is applied to amplified in situ nucleic acid detecting and imaging at the single-cell level.


Assuntos
Ácidos Nucleicos , DNA/química , Transferência de Energia , Corantes Fluorescentes , Polímeros
11.
J Immunol Res ; 2021: 6618837, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33791391

RESUMO

Mitochondrial Pyruvate Carrier 1 (MPC1), one of the rate-limiting proteins involved in glycolysis metabolism, has been demonstrated as a tumor inhibitor in several cancers. This study was conducted with the aim of exploring the role and underlying mechanisms of MPC2 in colorectal cancer (CRC). Here, we found that MPC2 expression was decreased in CRC samples. According to the analysis on our TMA data, lower expression of MPC2 is correlated with a higher incidence of distant metastasis and lymph node invasion, bigger tumor size, low survival rate of patients, and advanced T stages. Functionally, in vivo/vitro experiments showed that MPC2 knockdown induced CRC cell proliferation and growth, while MPC2 overexpression inhibited the proliferation and growth of CRC. Further study demonstrated that MPC2 knockdown resulted in aerobic glycolysis in CRC cells. Similarly, MPC2 overexpression in CRC cells also caused inhibited aerobic glycolysis. Further study found that MPC2 knockdown in CRC cell lines activated the mTOR signaling pathway, and the addition of rapamycin reversed the promoting effect of MPC2 knockdown on CRC proliferation and glycolysis. Likewise, the addition of MHY1485 also reversed the MPC2 overexpression's role in hindering aerobic glycolysis in CRC cells. Collectively, our study established that low expression of MPC2 led to CRC growth as well as aerobic glycolysis through the regulation of the mTOR pathway in CRC cells, indicating a potential biomarker and therapy target for CRC.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/genética , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Efeito Warburg em Oncologia , Idoso , Animais , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/genética , Proliferação de Células/genética , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Progressão da Doença , Regulação para Baixo , Feminino , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Células HCT116 , Humanos , Estimativa de Kaplan-Meier , Masculino , Camundongos , Pessoa de Meia-Idade , Proteínas de Transporte da Membrana Mitocondrial/análise , Proteínas de Transporte da Membrana Mitocondrial/genética , Transdução de Sinais/genética , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Front Oncol ; 10: 557730, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33244454

RESUMO

BACKGROUND: Aerobic glycolysis is a typical metabolic reprogramming in tumor cells, which contributes to the survival and proliferation of tumor cells. The underlying mechanisms controlling this metabolic switch in colorectal cancer (CRC), however, remain only partially understood. METHODS: The Cancer Genome Atlas (TCGA) dataset and Gene Expression Omnibus (GEO) (GDS4382, GSE6988, GSE35834) were used to analyzed the mRNA expression of THBS2. 392 paired samples of CRC and adjacent non-cancerous tissues were collected to detect the expression of THBS2 by IHC. The correlation of THBS2 expression with categorical clinical variables in patients with CRC was evaluated using chi-square analysis or Student's t-test. CCK-8, colony formation, and animal CT scan were used to functional analysis of THBS2 in CRC. RESULTS: Thrombospondin 2 (THBS2) is aberrantly upregulated and linked to a poor prognosis in CRC. Subsequent experiments also showed that THBS2 promotes the proliferation of CRC cells. In terms of mechanism, THBS2 interacted with Toll-like receptor 4 (TLR4), but not with the other toll-like receptors (TLRs), which upregulated the mRNA expression of GLUT1, HK2, ALDOA, PKM2, and LDHA and enhanced glycolytic capacity in CRC cells. Moreover, THBS2/TLR4 axis significantly increased the protein level of HIF-1α and blocking HIF-1α by siRNA reversed the enhanced glycolytic capacity and the upregulated expression of glycolytic enzymes in CRC cells. CONCLUSION: Our findings revealed that the THBS2/TLR4 axis contributes to HIF-1α derived glycolysis and eventually promotes CRC progress.

13.
Biochem Biophys Res Commun ; 515(3): 481-486, 2019 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-31167721

RESUMO

Immunoglobulins play important roles in antigen recognition during the immune response, and the complementarity-determining region (CDR) 3 of the heavy chain is considered as the critical antigen-binding site. We previously developed a statistical protocol for the extensive analysis of heavy chain variable region repertoires and the dynamics of their immune response using next-generation sequencing (NGS). The properties of important antibody heavy chains predicted in silico by the protocol were examined by gene synthesis and antibody protein expression; however, the corresponding light chain that matches with the heavy chain could not be predicted by our protocol. To understand the dynamics of the heavy chain and the effect of light chain pairing on it, we firstly tried to obtain an artificial light chain that pairs with a broad range of heavy chains and then analyzed its effect on the antigen binding of heavy chains upon pairing. During the pre-B cell stage, the surrogate light chain (SLC) could pair with the nascent immunoglobulin µ heavy chains (Ig-µH) and promote them to function in the periphery. On the basis of this property, we designed several versions of genetically engineered "common light chain" prototypes by modifying the SLC structure. Among them, the mouse-derived VpreB1λ5Cκ light chain showed acceptable matching property with several different heavy chains without losing specificity of the original heavy chains, though the antigen affinities were variable. The extent of matching depended on the heavy chain; surprisingly, a specific heavy chain (IGHV9-3) could match with two different conventional Vκs (IGKV3-2*01 and IGKV10-96*01) without losing the antigen affinities, whereas another heavy chain (IGHV1-72) completely lost its antigen affinities by the same matching. Thus, the results suggested that the antigen recognition of the heavy chain is variably affected by the paired light chain, and that the artificial light chain, Mm_VpreB1λ5Cκ, has the potential to be a "common light chain", providing a novel system to analyze the effects of light chains in antigen recognition of heavy chains.


Assuntos
Cadeias Pesadas de Imunoglobulinas/metabolismo , Cadeias Leves de Imunoglobulina/metabolismo , Sequência de Aminoácidos , Animais , Antígenos/metabolismo , Humanos , Cadeias Leves de Imunoglobulina/química , Camundongos , Modelos Biológicos , Proteínas Recombinantes/química
14.
J Vis Exp ; (145)2019 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-30933062

RESUMO

The immense adaptability of antigen recognition by antibodies is the basis of the acquired immune system. Despite our understanding of the molecular mechanisms underlying the production of the vast repertoire of antibodies by the acquired immune systems, it has not yet been possible to arrive at a global view of a complete antibody repertoire. In particular, B cell repertoires have been regarded as a black box because of their astronomical number of antibody clones. However, next-generation sequencing technologies are enabling breakthroughs to increase our understanding of the B cell repertoire. In this report, we describe a simple and efficient method to visualize and analyze whole individual mouse and human antibody repertoires. From the immune organs, representatively from spleen in mice and peripheral blood mononuclear cells in humans, total RNA was prepared, reverse transcribed, and amplified using the 5'-RACE method. Using a universal forward primer and antisense primers for the antibody class-specific constant domains, antibody mRNAs were uniformly amplified in proportions reflecting their frequencies in the antibody populations. The amplicons were sequenced by next-generation sequencing (NGS), yielding more than 105 antibody sequences per immunological sample. We describe the protocols for antibody sequence analyses including V(D)J-gene-segment annotation, a bird's-eye view of the antibody repertoire, and our computational methods.


Assuntos
Anticorpos/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Adulto , Animais , Linfócitos B/imunologia , Humanos , Leucócitos Mononucleares/metabolismo , Camundongos Endogâmicos C57BL
15.
Cell Death Dis ; 10(3): 217, 2019 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-30833544

RESUMO

Accumulating evidence from clinical and epidemiological studies has highlighted the close correlation between the individual risk of cancer and nervous system diseases. The expression of neuronal pentraxin 2 (NPTX2) is absent in Alzheimer's disease, anxiety, and depression. Herein, we found that NPTX2 mRNA and protein expression was significantly upregulated in colorectal carcinoma (CRC). NPTX2 expression level gradually increased with CRC progression and was closely associated with poor prognosis. In vitro and in vivo studies demonstrated that NPTX2 promoted CRC proliferation and metastasis through the activation of the Wnt/ß-catenin signaling pathway. As NPTX2 receptors are absent on CRC cells, NPTX2 was shown to physically interact with frizzled class receptor 6 (FZD6) to promote ß-catenin translocation into the cell nucleus, resulting in an increase in the expression of MYC, cyclin D1, snail, and N-cadherin along with a decrease in the expression of E-cadherin. Knockdown of FZD6 expression with a small-interfering RNA almost completely reversed the proliferative effects of NPTX2 on CRC development. In conclusion, NPTX2, a molecule related to nervous system diseases, promotes CRC cell proliferation and metastasis through the activation of the Wnt/ß-catenin pathway via direct interaction with FZD6.


Assuntos
Proteína C-Reativa/fisiologia , Neoplasias Colorretais/patologia , Receptores Frizzled/metabolismo , Neoplasias Hepáticas/secundário , Proteínas do Tecido Nervoso/fisiologia , Via de Sinalização Wnt , Proteína C-Reativa/metabolismo , Neoplasias Colorretais/metabolismo , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Proteínas do Tecido Nervoso/metabolismo , Regulação para Cima
16.
Surg Endosc ; 32(8): 3421-3431, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29435752

RESUMO

BACKGROUND AND AIMS: Gastric per-oral endoscopic myotomy (G-POEM) was introduced four years ago as an investigational procedure for refractory gastroparesis. The safety and efficacy were currently evaluated. With our recent studies on G-POEM, we share our experience and knowledge through the discussion of a detailed description of the procedure and review of the literature. To our knowledge, this is the first systemic review on this new therapeutic endoscopic procedure. METHODS: The indications and contraindications, various aspects of the procedure, and efficacy assessment are discussed based on our experience and current available data. RESULTS: Preoperative preparation, detailed description of the procedure, post-procedural care, and results in the literature are presented. The procedure is safe and effective. 70-80% of patients have significant improvement in overall symptoms and quality of life in short-term (6 months) follow-up, as assessed by Gastric Cardinal Symptom Index and Short Form 36. CONCLUSIONS: G-POEM is a feasible and effective procedure for refractory gastroparesis based on early and limited data. Well-designed prospective studies are expected to advance and evaluate this new procedure in the future.


Assuntos
Gastroparesia/cirurgia , Piloromiotomia/métodos , Seguimentos , Gastroparesia/diagnóstico , Humanos , Qualidade de Vida , Resultado do Tratamento
17.
Biochem Biophys Res Commun ; 495(1): 1411-1417, 2018 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-29191653

RESUMO

The pre-B cell receptor (pre-BCR), consisting of the µ heavy chain (µHC) and the surrogate light chain (SLC, Vpre-B and λ5), plays important roles during B cell development. The formation of the pre-BCR, which enables the nascent immunoglobulin HC to associate with the SLC, is considered a prerequisite for B cell development. However, a significant number of peripheral mature (leaky) B cells exist in SLC-deficient mice. These leaky B cells develop in the absence of pre-BCR and do not undergo the pre-BCR checkpoint. The antibody repertoires of leaky B cells thus reflect the absence of pre-BCR function. To investigate how the absence of the pre-BCR is circumvented by these leaky-B cells and examine the effect of the pre-BCR checkpoint on the antibody system, we analyzed the antibody repertoires of λ5-deficient (λ5-/-) mice using next-generation sequencing. In λ5-/- mice, spleen B cells displayed different patterns of VDJ-usage, relative to those in wild-type (WT) mice. Moreover, leaky B cells were neither derived from unusual B2 cells, characterized by particular LC gene rearrangements in the absence of pre-BCR signaling, nor from B1 cells, originating from different B cell progenitors. Analysis of the CDR-H3 amino acid sequences of µ-chain repertoires revealed that certain bone marrow B cells with particular CDR-H3 profiles undergo clonal expansion in λ5-/- mice. Part of these CDR-H3s contain arginine(s) in the middle of the CDR-H3 loop in λ5-/- mice, whereas few arginine(s) exist in this middle loop in WT CDR-H3s in the absence of clonal expansion. This CDR-H3 feature in λ5-/- mice presumably reflects the role of the pre-BCR in autoantibody regulation, since arginine(s) are often found in the antigen-binding site of autoantibodies. Here, we present a unique viewpoint on the role of pre-BCR, by assessing the whole antibody repertoire formed in SLC-deficient mice.


Assuntos
Autoanticorpos/imunologia , Linfócitos B/citologia , Linfócitos B/imunologia , Receptores de Células Precursoras de Linfócitos B/imunologia , Células Precursoras de Linfócitos B/citologia , Células Precursoras de Linfócitos B/imunologia , Animais , Diferenciação Celular/imunologia , Células Cultivadas , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
18.
Oncotarget ; 8(17): 27929-27942, 2017 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-28427191

RESUMO

Long non-coding RNAs (lncRNAs) serve critical roles in cancer development and progression. Herein, through next generation RNA sequencing and experimental validations, we determined the expression status of RP11-708H21.4 in colorectal cancer (CRC) and explored its clinical significance and biological functions in CRC. Differentially expressed lncRNAs from CRC samples and corresponding normal mucosa tissues was screened through RNA sequencing, and RP11-708H21.4 was selected for further experimental validation. The expression levels of RP11-708H21.4 in CRC tissues and cell lines were determined using qRT-PCR. Also, the relationship between the clinicopathological features and RP11-708H21.4 expression was analyzed. Cell viability was examined by CCK-8 and colony assays; cell migration and invasion were detected by transwell assays; cell cycle and cell apoptosis were analyzed by flow cytometry. The chemosensitivity of CRC cells to 5-Fluorouracil (5-FU) was also determined using CCK-8 assay. CRC xenograft tumor models were established to determine the biological functions of RP11-708H21.4 in vivo. Levels of cell cycle-related proteins and AKT/mTOR pathway-related proteins were detected by western blot assay. RP11-708H21.4 expression was aberrantly decreased in CRC, and its expression was closely associated with aggressive clinicopathologic features and unfavorable prognosis of CRC patients. Overexpressed RP11-708H21.4 suppresses CRC cell proliferation through inducing G1 arrest. Moreover, up-regulation of RP11-708H21.4 inhibits cell migration and invasion, causes cell apoptosis, and enhances 5-FU sensitivity of CRC cells. Finally, increased RP11-708H21.4 expression blocked AKT/mTOR pathway, and repressed in vivo CRC xenograft tumor growth. The results indicated that RP11-708H21.4 might have potential roles as a biomarker and a therapeutic target for CRC.


Assuntos
Biomarcadores Tumorais/genética , Carcinogênese/genética , Neoplasias Colorretais/genética , Regulação Neoplásica da Expressão Gênica , RNA Longo não Codificante/genética , Adulto , Idoso , Animais , Apoptose/genética , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Sobrevivência Celular , Transformação Celular Neoplásica/genética , Estudos de Coortes , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Neoplasias Colorretais/cirurgia , Regulação para Baixo , Feminino , Fluoruracila/farmacologia , Pontos de Checagem da Fase G1 do Ciclo Celular/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Mucosa Intestinal/patologia , Estimativa de Kaplan-Meier , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Longo não Codificante/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Serina-Treonina Quinases TOR/metabolismo , Regulação para Cima , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Biochem Biophys Res Commun ; 487(2): 300-306, 2017 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-28412367

RESUMO

Vast diversity and high specificity of antigen recognition by antibodies are hallmarks of the acquired immune system. Although the molecular mechanisms that yield the extremely large antibody repertoires are precisely understood, comprehensive description of the global antibody repertoire generated in individual bodies has been hindered by the lack of powerful measures. To obtain holistic understanding of the antibody-repertoire space, we used next-generation sequencing (NGS) to analyze the deep profiles of naive and antigen-responding repertoires of the IgM, IgG1, and IgG2c classes formed in individual mice. The overall landscapes of naive IgM repertoires were almost the same for each mouse, whereas those of IgG1 and IgG2c differed considerably among naive individuals. Next, we immunized mice with a model antigen, nitrophenol (NP)-hapten linked to chicken γ-globulin (CGG) carrier, and compared the antigen-responding repertoires in individual mice. To extract the complete antigen response, we developed an intelligible method for detecting common components of antigen-responding repertoires. The major responding antibodies were IGHV1-72/IGHD1-1/IGHJ2 for NP-hapten and IGHV9-3/IGHD3-1/IGHJ2 for CGG-carrier protein. The antigen-binding specificities of the identified antibodies were confirmed through ELISA after antibody-gene synthesis and expression of the corresponding NGS reads. Thus, we deciphered antigen-responding antibody repertoires by inclusively analyzing the antibody-repertoire space generated in individual bodies by using NGS, which avoided inadvertent omission of key antibody repertoires.


Assuntos
Reações Antígeno-Anticorpo/imunologia , Descoberta de Drogas/métodos , Mapeamento de Epitopos/métodos , Ensaios de Triagem em Larga Escala/métodos , Engenharia de Proteínas/métodos , Análise de Sequência de Proteína/métodos , Animais , Feminino , Camundongos , Camundongos Endogâmicos C57BL
20.
Medicine (Baltimore) ; 95(33): e4606, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27537596

RESUMO

Thalidomide may be used for the treatment of gastrointestinal vascular malformation (GIVM), but the long-term response and adverse effects are unknown. Aim to study the recurrence rate of GIVM bleeding after thalidomide treatment, the response to treatment, and the adverse effects.This was a retrospective study of 80 patients with GIVM treated with thalidomide between November 2003 and November 2013. Patients received a course of 100 mg/day of thalidomide for 4 months and were followed up for at least 1 year. The response rate during follow-up, the recurrence rate after the 1st course of treatment, and the rate of retreatment were assessed. Comorbidities, the need for blood transfusion, yearly bleeding episodes, hemoglobin levels, hospitalization after thalidomide treatment, and the rate of adverse effects were also examined.The overall response rate during follow-up was 79.5% (62/78). The recurrence rate was 21.0% after the 1st course of thalidomide. The response rate of retreatment was 100%. After thalidomide treatment, yearly blood transfusion amounts, yearly bleeding episodes, and yearly hospitalization numbers were significantly decreased, while hemoglobin levels were significantly increased (P < 0.001). Adverse effects were observed in 60.0% (48/80) of the patients. Serious adverse effects were reported in 31.3% (25/80). The overall response rate was 76.7% (23/30) in 30 patients with comorbidities, while the rate was 78.0% (39/50) in patients without comorbidities (P = 0.55). The rate of serious adverse effects was similar between the comorbidities (33.3%) and no-comorbidities groups (30.0%) (P = 0.76).Thalidomide showed a good response rate and low adverse effect rate in patients with recurrent gastrointestinal bleeding due to GIVM.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Trato Gastrointestinal/irrigação sanguínea , Talidomida/uso terapêutico , Malformações Vasculares/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Hemorragia Gastrointestinal/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Malformações Vasculares/complicações
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