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1.
Acta Crystallogr F Struct Biol Commun ; 80(Pt 7): 148-153, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38940939

RESUMO

Protein tyrosine phosphatase non-receptor type 21 (PTPN21) is a cytosolic protein tyrosine phosphatase that regulates cell growth and invasion. Due to its oncogenic properties, PTPN21 has recently emerged as a potential therapeutic target for cancer. In this study, the three-dimensional structure of the PTPN21 FERM domain was determined at 2.1 Šresolution by X-ray crystallography. The crystal structure showed that this domain harbors canonical FERM folding and consists of three subdomains that are tightly packed via highly conserved intramolecular hydrophobic interactions. Consistent with this, the PTPN21 FERM domain shares high structural homology with several other FERM domains. Moreover, structural superimposition demonstrated two putative protein-binding sites of the PTPN21 FERM domain, which are presumed to be associated with interaction with its binding partner, kinesin family member 1C. Thus, these data suggest that the FERM domain of PTPN21 serves as a module that mediates protein-protein interaction, like other FERM domains.


Assuntos
Modelos Moleculares , Humanos , Cristalografia por Raios X , Ligação Proteica , Sítios de Ligação , Sequência de Aminoácidos , Domínios Proteicos , Proteínas Tirosina Fosfatases não Receptoras/química , Proteínas Tirosina Fosfatases não Receptoras/metabolismo , Proteínas Tirosina Fosfatases não Receptoras/genética , Interações Hidrofóbicas e Hidrofílicas , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
2.
Proteins ; 92(1): 44-51, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37553948

RESUMO

The activation or inactivation of B-cell lymphoma-2 (Bcl-2) antagonist/killer (Bak) is critical for controlling mitochondrial outer membrane permeabilization-dependent apoptosis. Its pro-apoptotic activity is controlled by intermolecular interactions with the Bcl-2 homology 3 (BH3) domain, which is accommodated in the hydrophobic pocket of Bak. Bcl-2-interacting protein 5 (Bnip5) is a noncanonical BH3 domain-containing protein that interacts with Bak. Bnip5 is characterized by its controversial effects on the regulation of the pro-apoptotic activity of Bak. In the present study, we determined the crystal structure of Bak bound to Bnip5 BH3. The intermolecular association appeared to be typical at first glance, but we found that it is maintained by tight hydrophobic interactions together with hydrogen/ionic bonds, which accounts for their high binding affinity with a dissociation constant of 775 nM. Structural analysis of the complex showed that Bnip5 interacts with Bak in a manner similar to that of the Bak-activating pro-apoptotic factor peroxisomal testis-enriched protein 1, particularly in the destabilization of the intramolecular electrostatic network of Bak. Our structure is considered to reflect the initial point of drastic and consecutive conformational and stoichiometric changes in Bak induced by Bnip5 BH3, which helps in explaining the effects of Bnip5 in regulating Bak-mediated apoptosis.


Assuntos
Proteínas Proto-Oncogênicas c-bcl-2 , Proteína Killer-Antagonista Homóloga a bcl-2 , Proteínas Proto-Oncogênicas c-bcl-2/química , Proteína Killer-Antagonista Homóloga a bcl-2/química , Proteína Killer-Antagonista Homóloga a bcl-2/metabolismo , Domínios Proteicos , Proteína bcl-X/metabolismo , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3/metabolismo , Apoptose/fisiologia
3.
J Microbiol ; 61(8): 755-764, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37684534

RESUMO

Human papillomaviruses (HPVs) can increase the proliferation of infected cells during HPV-driven abnormalities, such as cervical cancer or benign warts. To date, more than 200 HPV genotypes have been identified, most of which are classified into three major genera: Alphapapillomavirus, Betapapillomavirus, and Gammapapillomavirus. HPV genomes commonly encode two structural (L1 and L2) and seven functional (E1, E2, E4-E7, and E8) proteins. L2, the minor structural protein of HPVs, not only serves as a viral capsid component but also interacts with various human proteins during viral infection. A recent report revealed that L2 of HPV16 recruits polo-like kinase 1 (Plk1), a master regulator of eukaryotic mitosis and cell cycle progression, for the delivery of viral DNA to mitotic chromatin during HPV16 infection. In this study, we verified the direct and potent interactions between the polo-box domain (PBD) of Plk1 and PBD-binding motif (S-S-pT-P)-containing phosphopeptides derived from L2 of HPV16/HPV18 (high-risk alphapapillomaviruses), HPV5b (low-risk betapapillomavirus), and HPV4 (low-risk gammapapillomavirus). Subsequent structural determination of the Plk1 PBD bound to the HPV18 or HPV4 L2-derived phosphopeptide demonstrated that they interact with each other in a canonical manner, in which electrostatic interactions and hydrogen bonds play key roles in sustaining the complex. Therefore, our structural and biochemical data imply that Plk1 is a broad binding target of L2 of various HPV genotypes belonging to the Alpha-, Beta-, and Gammapapillomavirus genera.


Assuntos
Papillomavirus Humano , Infecções por Papillomavirus , Humanos , Proteínas do Capsídeo/genética , Fosfopeptídeos/química , Fosfopeptídeos/metabolismo , Quinase 1 Polo-Like
4.
PLoS Biol ; 21(6): e3002156, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37315086

RESUMO

Bak is a critical executor of apoptosis belonging to the Bcl-2 protein family. Bak contains a hydrophobic groove where the BH3 domain of proapoptotic Bcl-2 family members can be accommodated, which initiates its activation. Once activated, Bak undergoes a conformational change to oligomerize, which leads to mitochondrial destabilization and the release of cytochrome c into the cytosol and eventual apoptotic cell death. In this study, we investigated the molecular aspects and functional consequences of the interaction between Bak and peroxisomal testis-specific 1 (Pxt1), a noncanonical BH3-only protein exclusively expressed in the testis. Together with various biochemical approaches, this interaction was verified and analyzed at the atomic level by determining the crystal structure of the Bak-Pxt1 BH3 complex. In-depth biochemical and cellular analyses demonstrated that Pxt1 functions as a Bak-activating proapoptotic factor, and its BH3 domain, which mediates direct intermolecular interaction with Bak, plays a critical role in triggering apoptosis. Therefore, this study provides a molecular basis for the Pxt1-mediated novel pathway for the activation of apoptosis and expands our understanding of the cell death signaling coordinated by diverse BH3 domain-containing proteins.


Assuntos
Proteínas Proto-Oncogênicas c-bcl-2 , Humanos , Masculino , Apoptose/fisiologia , Proteína X Associada a bcl-2 , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3/metabolismo , Proteínas de Transporte/metabolismo , Mitocôndrias/metabolismo
5.
J Obes Metab Syndr ; 32(1): 1-24, 2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-36945077

RESUMO

The goal of the 8th edition of the Clinical Practice Guidelines for Obesity is to help primary care physician provide safe, effective care to patients with obesity by offering evidence-based recommendations to improve the quality of treatment. The Committee for Clinical Practice Guidelines comprised individuals with multidisciplinary expertise in obesity management. A steering board of seven experts oversaw the entire project. Recommendations were developed as the answers to key questions formulated in patient/problem, intervention, comparison, outcomes (PICO) format. Guidelines underwent multi-level review and cross-checking and received endorsement from relevant scientific societies. This edition of the guidelines includes criteria for diagnosing obesity, abdominal obesity, and metabolic syndrome; evaluation of obesity and its complications; weight loss goals; and treatment options such as diet, exercise, behavioral therapy, pharmacotherapy, and bariatric and metabolic surgery for Korean people with obesity. Compared to the previous edition of the guidelines, the current edition includes five new topics to keep up with the constantly evolving field of obesity: diagnosis of obesity, obesity in women, obesity in patients with mental illness, weight maintenance after weight loss, and the use of information and communication technology-based interventions for obesity treatment. This edition of the guidelines features has improved organization, more clearly linking key questions in PICO format to recommendations and key references. We are confident that these new Clinical Practice Guidelines for Obesity will be a valuable resource for all healthcare professionals as they describe the most current and evidence-based treatment options for obesity in a well-organized format.

6.
Ann Hematol ; 102(4): 877-888, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36840791

RESUMO

This long-term, retrospective, single-center study evaluated real-world clinical outcomes of gastric mucosa-associated lymphoid tissue (MALT) lymphoma using different therapeutic modalities and analyzed factors affecting survival outcomes and long-term prognosis. We enrolled 203 patients with pathologically confirmed low-grade gastric MALT lymphoma and examined their treatment responses. Helicobacter pylori eradication was performed in all patients with H. pylori infection (HPI) and localized stage gastric MALT lymphoma. All patients underwent pre-treatment and physical evaluations, with complete blood count, biochemistry panel, and staging workup. Among 144 HPI-positive patients with stage I or II1-2 disease who underwent H. pylori eradication, 112 (77.8%) achieved complete remission (CR). All HPI-negative patients who received first-line radiotherapy achieved CR (100%), but only 22 of 27 first-line chemotherapy-treated patients achieved CR (81.5%). Lesions in the proximal upper-third or in multiple locations and an invasion depth to the submucosa or deeper were associated with poor response to eradication, and HPI negativity was significantly correlated with poor progression-free survival. HPI eradication treatment should be the first-line treatment for patients with localized stage HPI-positive gastric MALT lymphoma. The "watch-and-wait" strategy should be adopted for delayed responders. We suggest radiotherapy for patients with a localized HPI-negative status or when eradication has failed.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Linfoma de Zona Marginal Tipo Células B , Neoplasias Gástricas , Humanos , Linfoma de Zona Marginal Tipo Células B/tratamento farmacológico , Estudos Retrospectivos , Infecções por Helicobacter/complicações , Prognóstico , Neoplasias Gástricas/patologia , Antibacterianos/uso terapêutico
7.
Turk J Gastroenterol ; 33(9): 785-792, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35946887

RESUMO

BACKGROUND: Accurate staging for depth of invasion (T stage) of early gastric cancer is critical for determining the treatment modality. Endoscopic ultrasonography is a reliable method for assessing the T stage. However, its diagnostic accuracy varies. The aim of this study is to investigate clinicopathologic factors affecting the diagnostic accuracy of endoscopic ultrasonography in early gastric cancer. METHODS: Patients with early gastric cancer who had undergone endoscopic resection or gastrectomy were included. The diagnostic accuracy of endoscopic ultrasonography was evaluated by comparing the T stage by endoscopic ultrasonography with histopathology of the resected specimen. Subgroup analysis was performed according to the endoscopic resection criteria. RESULTS: A total of 223 early gastric cancer lesions were included. The overall accuracy of endoscopic ultrasonography for T staging was 66.4%. The diagnostic accuracy for lesions ≤2 cm was significantly higher than for those of 2-3 cm (odds ratio 3.59) or those >3 cm (odds ratio 5.47). The diagnostic accuracy was significantly decreased in lesions with ulceration (odds ratio 2.62) or non-flat morphology (odds ratio 2.94). The accuracy of endoscopic ultrasonography for lesions corresponding to the absolute endoscopic resection criteria was significantly higher than for those corresponding to the expanded criteria (97.3% vs 71.9%, P = .002). Of the tumors that were overestimated by endoscopic ultrasonography treated with gastrectomy, 93.3% corresponded to the expanded criteria. CONCLUSION: Endoscopic ultrasonography had poor accuracy in early gastric cancer lesions larger than 2 cm, those with ulceration, and those with non-flat morphology, that is, lesions corresponding to the expanded criteria were more frequently overstaged by endoscopic ultrasonography. Such early gastric cancers should be carefully considered when staging by endoscopic ultrasonography before gastrectomy.


Assuntos
Neoplasias Gástricas , Detecção Precoce de Câncer , Endossonografia/métodos , Gastrectomia , Mucosa Gástrica/patologia , Humanos , Estadiamento de Neoplasias , Estudos Retrospectivos , Neoplasias Gástricas/diagnóstico por imagem , Neoplasias Gástricas/cirurgia , Úlcera/patologia
8.
Biochem Biophys Res Commun ; 625: 174-180, 2022 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-35964379

RESUMO

Antiapoptotic B-cell lymphoma-2 (Bcl-2) proteins suppress apoptosis by interacting with proapoptotic regulators. They commonly contain a hydrophobic groove where the Bcl-2 homology 3 (BH3) domain of Bcl-2 family members or BH3 domain-containing non-Bcl-2 family proteins can be accommodated. Peroxisomal testis-specific 1 (Pxt1) was previously identified as a male germ cell-specific protein whose overexpression causes germ cell apoptosis and infertility in male mice. Sequence and biochemical analyses also showed that human Pxt1, which is composed of 134 amino acids and is longer than mouse Pxt1 consisting of only 51 amino acids, has a BH3 domain that interacts with antiapoptotic Bcl-2 proteins, including Bcl-2 and Bcl-xL. In this study, we determined the crystal structure of Bcl-xL bound to the human Pxt1 BH3 domain. The five BH3 consensus residues are well conserved in the human Pxt1 BH3 domain and make a critical contribution to the complex formation in a canonical manner. Structural and biochemical analyses also demonstrated that Bcl-xL interacts with the BH3 domain of human Pxt1 but not with that of mouse Pxt1, and that residues 76-83 of human Pxt1, absent in mouse Pxt1, play a pivotal role in the intermolecular binding to Bcl-xL. While Bcl-xL consistently colocalized with human Pxt1 in mitochondria, it did not do so with mouse Pxt1, when expressed in HeLa cells. Collectively, these data verified that human and mouse Pxt1 differ in their binding ability to the antiapoptotic regulator Bcl-xL, which might affect their functionality in controlling apoptosis.


Assuntos
Proteínas Reguladoras de Apoptose , Testículo , Sequência de Aminoácidos , Aminoácidos/metabolismo , Animais , Apoptose , Proteínas Reguladoras de Apoptose/metabolismo , Células HeLa , Humanos , Masculino , Camundongos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Testículo/metabolismo , Proteína bcl-X/metabolismo
9.
IEEE Trans Biomed Eng ; 69(11): 3538-3550, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35522630

RESUMO

OBJECTIVE: Automated registration algorithms for a pair of 2D X-ray mammographic images taken from two standard imaging angles, namely, the craniocaudal (CC) and the mediolateral oblique (MLO) views, are developed. METHODS: A fully convolutional neural network, a type of convolutional neural network (CNN), is employed to generate a pixel-level deformation field, which provides a mapping between masses in the two views. Novel distance-based regularization is employed, which contributes significantly to the performance. RESULTS: The developed techniques are tested using real 2D mammographic images, slices from real 3D mammographic images, and synthetic mammographic images. Architectural variations of the neural network are investigated and the performance is characterized from various aspects including image resolution, breast density, lesion size, lesion subtlety, and lesion Breast Imaging-Reporting and Data System (BI-RADS) category. Our network outperformed the state-of-the-art CNN-based and non-CNN-based registration techniques, and showed robust performance across various tissue/lesion characteristics. CONCLUSION: The proposed methods provide a useful automated tool for co-locating lesions between the CC and MLO views even in challenging cases. SIGNIFICANCE: Our methods can aid clinicians to establish lesion correspondence quickly and accurately in the dual-view X-ray mammography, improving diagnostic capability.


Assuntos
Mamografia , Redes Neurais de Computação , Raios X , Mamografia/métodos , Algoritmos
10.
J Microbiol ; 60(4): 395-401, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35089587

RESUMO

High-risk genotypes of human papillomaviruses (HPVs) are directly implicated in various abnormalities associated with cellular hyperproliferation, including cervical cancer. E6 is one of two oncoproteins encoded in the HPV genome, which recruits diverse PSD-95/Dlg/ZO-1 (PDZ) domain-containing human proteins through its C-terminal PDZ-binding motif (PBM) to be degraded by means of the proteasome pathway. Among the three PDZ domain-containing protein tyrosine phosphatases, protein tyrosine phosphatase non-receptor type 3 (PTPN3) and PTPN13 were identified to be recognized by HPV E6 in a PBM-dependent manner. However, whether HPV E6 associates with PTPN4, which also has a PDZ domain and functions as an apoptosis regulator, remains undetermined. Herein, we present structural and biochemical evidence demonstrating the direct interaction between the PBM of HPV16 E6 and the PDZ domain of human PTPN4 for the first time. X-ray crystallographic structure determination and binding measurements using isothermal titration calorimetry demonstrated that hydrophobic interactions in which Leu158 of HPV16 E6 plays a key role and a network of intermolecular hydrogen bonds sustain the complex formation between PTPN4 PDZ and the PBM of HPV16 E6. In addition, it was verified that the corresponding motifs from several other high-risk HPV genotypes, including HPV18, HPV31, HPV33, and HPV45, bind to PTPN4 PDZ with comparable affinities, suggesting that PTPN4 is a common target of various pathogenic HPV genotypes.


Assuntos
Alphapapillomavirus , Proteínas Oncogênicas Virais , Papillomaviridae , Proteína Tirosina Fosfatase não Receptora Tipo 4 , Proteínas Repressoras , Alphapapillomavirus/química , Alphapapillomavirus/metabolismo , Humanos , Proteínas Oncogênicas Virais/química , Proteínas Oncogênicas Virais/metabolismo , Domínios PDZ , Papillomaviridae/metabolismo , Ligação Proteica , Proteína Tirosina Fosfatase não Receptora Tipo 4/química , Proteína Tirosina Fosfatase não Receptora Tipo 4/metabolismo , Proteínas Repressoras/química , Proteínas Repressoras/metabolismo
11.
Gut Liver ; 16(5): 746-753, 2022 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34916337

RESUMO

Background/Aims: There have been few studies regarding the prognosis of intestinal Behçet's disease (iBD) patients according to consensus-based diagnostic categories, which reflects the typicality of intestinal ulcers, the presence of oral ulcers, and the accompanying systemic manifestations. Methods: The medical records of patients who had ileocolonic ulcers with a clinical impression of iBD were reviewed. The patients were categorized according to the diagnostic algorithm at the time of diagnosis. Adverse events were defined as major surgery or admission related to iBD deterioration. Results: A total of 163 patients were included in the study. The male-to-female ratio was 1:1.2, and the mean age at the time of diagnosis was 48.9±15.9 years. The numbers of patients who met the definite, probable, suspected, and nondiagnostic iBD criteria were 19 (11.7%), 61 (37.4%), 38 (23.3%), and 45 (27.6%), respectively. The event-free survival of patients with definite, probable, and suspected iBD was significantly shorter than that of patients with nondiagnostic iBD (p=0.026), while there was no significant difference among the definite iBD, probable iBD, and suspected iBD groups (p=0.596). After excluding patients with nondiagnostic iBD, multivariate analysis showed that anemia, fever, colonic involvement other than the ileocecum, and accompanying hematologic disorders at the time of diagnosis were significantly associated with the development of adverse events. Conclusions: The clinical course of patients with definite, probable, and suspected iBD is distinguished from that of patients with nondiagnostic iBD, but patients with definite, probable, and suspected iBD share similar clinical courses.


Assuntos
Síndrome de Behçet , Enteropatias , Síndrome de Behçet/complicações , Síndrome de Behçet/diagnóstico , Consenso , Feminino , Humanos , Enteropatias/complicações , Enteropatias/diagnóstico , Intestinos , Masculino , Úlcera
12.
Surg Endosc ; 36(3): 2087-2095, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-33913030

RESUMO

BACKGROUND AND AIMS: Sessile serrated lesions (SSLs) are more prone to incomplete resection than conventional adenomas. This study evaluated whether circumferential submucosal incision prior to endoscopic mucosal resection (CSI-EMR) can increase the rate of complete and en bloc resections of colorectal lesions with endoscopic features of SSL. METHODS: Retrospective analyses and propensity score matching were performed for the resection of colorectal lesions ≥ 10 mm with endoscopic features of SSL. RESULTS: After 1:1 ratio matching, 127 lesions in the CSI-EMR group and 127 in the EMR group were selected for analysis. The median size of the lesions was 15 mm (IQR 12-16) in both groups. There was no significant difference in either the complete resection rate or en bloc resection rate between CSI-EMR and EMR groups (96.9% vs. 92.9%, P = 0.155; 92.1% vs. 89.0%, P = 0.391). By contrast, the R0 resection rate was significantly higher in the CSI-EMR group than in the EMR group (89.8% vs. 59.8%, P < 0.001). The median procedure time was significantly longer in the CSI-EMR group than in the EMR group (6.28 min vs. 2.55 min, P < 0.001), whereas there was no significant difference between the two groups in the incidence of adverse events or recurrence rate. Multivariate analysis showed that CSI-EMR was the only factor significantly associated with R0 resection (P < 0.001). CONCLUSIONS: For colorectal lesions with endoscopic features of SSL, CSI-EMR does not increase the complete or en bloc resection rate, but does increase the R0 resection rate. The procedure time is longer for CSI-EMR than EMR. The association of CSI-EMR with R0 resection and non-recurrence should be further evaluated.


Assuntos
Adenoma , Neoplasias Colorretais , Ressecção Endoscópica de Mucosa , Adenoma/patologia , Adenoma/cirurgia , Neoplasias Colorretais/patologia , Neoplasias Colorretais/cirurgia , Ressecção Endoscópica de Mucosa/métodos , Humanos , Mucosa Intestinal/patologia , Mucosa Intestinal/cirurgia , Estudos Retrospectivos , Resultado do Tratamento
13.
Biochip J ; 15(4): 371-380, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34745431

RESUMO

Over the past 6 years, acute respiratory infections have constituted an average of more than 70,000 cases in South Korea. It results in a high mortality rate in infants and the elderly with weak immunity. There are several types of respiratory viruses that invade the human respiratory tract and cause infectious disease. Reverse transcription PCR (RT-PCR) is mainly used for respiratory virus detection owing to its high sensitivity and reproducibility. In response, a multiplex real-time RT-PCR (rRT-PCR) assay was developed for the detection of influenza A and B viruses, parainfluenza viruses 1-4 (PIV1-4), human metapneumovirus, adenovirus, human rhinovirus, respiratory syncytial virus (RSV), and SARS-CoV-2. Detection ability of RT-PCR assay was confirmed by applying it to a portable device capable of point-of-care testing (POCT). Amplicons were synthesized using primer pairs and probe sets designed for each target virus, and a standard curve was constructed to confirm the limit of detection. An experiment using nasopharyngeal swab samples was conducted to understand the field applicability of the rRT-PCR assay. Detection was confirmed in most samples. This study demonstrated that rapid and accurate detection results can be obtained using the multiplex rRT-PCR based POC test, and that it is possible to detect 14 types of respiratory viruses that are generally difficult to distinguish at the same time, enabling timely treatment. Furthermore, we expect that the portable PCR device can significantly reduce the processing procedure of clinical samples before testing, which is the main disadvantage of common RT-PCR tests and can help reduce costs.

14.
Int J Mol Sci ; 22(15)2021 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-34361089

RESUMO

UBR box E3 ligases, also called N-recognins, are integral components of the N-degron pathway. Representative N-recognins include UBR1, UBR2, UBR4, and UBR5, and they bind destabilizing N-terminal residues, termed N-degrons. Understanding the molecular bases of their substrate recognition and the biological impact of the clearance of their substrates on cellular signaling pathways can provide valuable insights into the regulation of these pathways. This review provides an overview of the current knowledge of the binding mechanism of UBR box N-recognin/N-degron interactions and their roles in signaling pathways linked to G-protein-coupled receptors, apoptosis, mitochondrial quality control, inflammation, and DNA damage. The targeting of these UBR box N-recognins can provide potential therapies to treat diseases such as cancer and neurodegenerative diseases.


Assuntos
Apoptose , Dano ao DNA , Inflamação/patologia , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais , Ubiquitina-Proteína Ligases/metabolismo , Animais , Humanos , Inflamação/metabolismo
15.
Front Immunol ; 12: 652709, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34211461

RESUMO

Small heterodimer partner interacting leucine zipper protein (SMILE) is an orphan nuclear receptor and a member of the bZIP family of proteins. We investigated the mechanism by which SMILE suppressed the development of inflammatory bowel disease (IBD) using a DSS-induced colitis mouse model and peripheral blood mononuclear cells (PBMCs) from patients with ulcerative colitis (UC). Metformin, an antidiabetic drug and an inducer of AMPK, upregulated the level of SMILE in human intestinal epithelial cells and the number of SMILE-expressing cells in colon tissues from DSS-induced colitis mice compared to control mice. Overexpression of SMILE using a DNA vector reduced the severity of DSS-induced colitis and colitis-associated intestinal fibrosis compared to mock vector. Furthermore, SMILE transgenic mice showed ameliorated DSS-induced colitis compared with wild-type mice. The mRNA levels of SMILE and Foxp3 were downregulated and SMILE expression was positively correlated with Foxp3 in PBMCs from patients with UC and an inflamed mucosa. Metformin increased the levels of SMILE, AMPK, and Foxp3 but decreased the number of interleukin (IL)-17-producing T cells among PBMCs from patients with UC. These data suggest that SMILE exerts a therapeutic effect on IBD by modulating IL-17 production.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Doenças Inflamatórias Intestinais/etiologia , Doenças Inflamatórias Intestinais/metabolismo , Zíper de Leucina/genética , Metformina/farmacologia , Multimerização Proteica/efeitos dos fármacos , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Células Epiteliais/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Doenças Inflamatórias Intestinais/patologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Masculino , Camundongos , Camundongos Transgênicos , Ligação Proteica
16.
Cell Mol Life Sci ; 78(7): 3725-3741, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33687501

RESUMO

Protein arginylation is a critical regulator of a variety of biological processes. The ability to uncover the global arginylation pattern and its associated signaling pathways would enable us to identify novel disease targets. Here, we report the development of a tool able to capture the N-terminal arginylome. This tool, termed R-catcher, is based on the ZZ domain of p62, which was previously shown to bind N-terminally arginylated proteins. Mutating the ZZ domain enhanced its binding specificity and affinity for Nt-Arg. R-catcher pulldown coupled to LC-MS/MS led to the identification of 59 known and putative arginylated proteins. Among these were a subgroup of novel ATE1-dependent arginylated ER proteins that are linked to diverse biological pathways, including cellular senescence and vesicle-mediated transport as well as diseases, such as Amyotrophic Lateral Sclerosis and Alzheimer's disease. This study presents the first molecular tool that allows the unbiased identification of arginylated proteins, thereby unlocking the arginylome and provide a new path to disease biomarker discovery.


Assuntos
Aminoaciltransferases/metabolismo , Arginina/metabolismo , Retículo Endoplasmático/metabolismo , Vetores Genéticos/genética , Proteínas de Membrana/metabolismo , Processamento de Proteína Pós-Traducional , Aminoaciltransferases/química , Aminoaciltransferases/genética , Arginina/química , Arginina/genética , Células HeLa , Humanos , Proteínas de Membrana/genética , Especificidade por Substrato
17.
Mol Cells ; 44(1): 26-37, 2021 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-33431714

RESUMO

Human papillomaviruses (HPVs) cause cellular hyperproliferation-associated abnormalities including cervical cancer. The HPV genome encodes two major viral oncoproteins, E6 and E7, which recruit various host proteins by direct interaction for proteasomal degradation. Recently, we reported the structure of HPV18 E7 conserved region 3 (CR3) bound to the protein tyrosine phosphatase (PTP) domain of PTPN14, a well-defined tumor suppressor, and found that this intermolecular interaction plays a key role in E7-driven transformation and tumorigenesis. In this study, we carried out a molecular analysis of the interaction between CR3 of HPV18 E7 and the PTP domain of PTPN21, a PTP protein that shares high sequence homology with PTPN14 but is putatively oncogenic rather than tumor-suppressive. Through the combined use of biochemical tools, we verified that HPV18 E7 and PTPN21 form a 2:2 complex, with a dissociation constant of 5 nM and a nearly identical binding manner with the HPV18 E7 and PTPN14 complex. Nevertheless, despite the structural similarities, the biological consequences of the E7 interaction were found to differ between the two PTP proteins. Unlike PTPN14, PTPN21 did not appear to be subjected to proteasomal degradation in HPV18-positive HeLa cervical cancer cells. Moreover, knockdown of PTPN21 led to retardation of the migration/invasion of HeLa cells and HPV18 E7-expressing HaCaT keratinocytes, which reflects its protumor activity. In conclusion, the associations of the viral oncoprotein E7 with PTPN14 and PTPN21 are similar at the molecular level but play different physiological roles.


Assuntos
Alphapapillomavirus/genética , Proteínas E7 de Papillomavirus/metabolismo , Proteínas Tirosina Fosfatases não Receptoras/metabolismo , Sequência de Aminoácidos , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Genótipo , Humanos , Modelos Moleculares , Invasividade Neoplásica , Complexo de Endopeptidases do Proteassoma/metabolismo , Ligação Proteica , Proteínas Tirosina Fosfatases não Receptoras/química , Proteólise
18.
Surg Endosc ; 35(9): 5096-5103, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-32989532

RESUMO

BACKGROUND AND AIMS: This study was performed to compare endoscopic mucosal resection (EMR) with hot snare polypectomy (HSP) in terms of the complete resection rate and the incidence of adverse events for resecting small (5-10 mm) colorectal polyps. METHODS: Small colorectal polyps (5-10 mm) with neoplastic features were randomly allocated to either the HSP or EMR group. A submucosal injection was performed prior to hot snaring in the EMR group only. Complete resection was defined as the absence of neoplastic tissue from two additional biopsies of the polypectomy site. R0 resection was defined as the absence of neoplastic tissue at the margin of the resected specimen. RESULTS: A total of 362 colon polyps from 272 patients were included, and 167 polyps in the HSP group and 155 polyps in the EMR group were analyzed. Between the polypectomy techniques, there was no significant difference in the complete resection rates, which were 96.4% (161/167) in the HSP group and 95.5% (148/155) in the EMR group (P = 0.67). The R0 resection rate in the HSP and EMR groups was significantly different, with 49.7% (83/167) and 74.8% (116/155), respectively (P < 0.001). There was no significant difference in the incidence of adverse events between the two groups. CONCLUSIONS: The complete resection rates for small (5-10 mm) polyps were not different between HSP and EMR. TRIAL REGISTRY: ClincialTrials.gov number NCT02239536.


Assuntos
Pólipos do Colo , Ressecção Endoscópica de Mucosa , Biópsia , Pólipos do Colo/cirurgia , Colonoscopia , Humanos , Microcirurgia
19.
Proc Natl Acad Sci U S A ; 117(33): 19982-19993, 2020 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-32753382

RESUMO

The underlying mechanism of necroptosis in relation to cancer is still unclear. Here, MYC, a potent oncogene, is an antinecroptotic factor that directly suppresses the formation of the RIPK1-RIPK3 complex. Gene set enrichment analyses reveal that the MYC pathway is the most prominently down-regulated signaling pathway during necroptosis. Depletion or deletion of MYC promotes the RIPK1-RIPK3 interaction, thereby stabilizing the RIPK1 and RIPK3 proteins and facilitating necroptosis. Interestingly, MYC binds to RIPK3 in the cytoplasm and inhibits the interaction between RIPK1 and RIPK3 in vitro. Furthermore, MYC-nick, a truncated form that is mainly localized in the cytoplasm, prevented TNF-induced necroptosis. Finally, down-regulation of MYC enhances necroptosis in leukemia cells and suppresses tumor growth in a xenograft model upon treatment with birinapant and emricasan. MYC-mediated suppression of necroptosis is a mechanism of necroptosis resistance in cancer, and approaches targeting MYC to induce necroptosis represent an attractive therapeutic strategy for cancer.


Assuntos
Leucemia/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Animais , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Humanos , Leucemia/genética , Leucemia/fisiopatologia , Camundongos , Camundongos Endogâmicos BALB C , Necroptose , Ligação Proteica , Transporte Proteico , Proteínas Proto-Oncogênicas c-myc/genética , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Transdução de Sinais
20.
J Obes Metab Syndr ; 29(2): 99-109, 2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32378399

RESUMO

Obesity is a serious and growing worldwide health challenge associated with type 2 diabetes mellitus, cardiovascular disease, osteoarthritis, some cancers, sleep apnea, asthma, and nonalcoholic fatty liver. The Korean Society for the Study of Obesity recommends that pharmacotherapy should be considered when intensive lifestyle modifications fail to achieve a weight reduction in obese patients with a body mass index ≥25 kg/m2. Long-term medications for obesity have traditionally fallen into two major categories: centrally acting anorexiant medications and peripherally acting medications, such as orlistat. In this paper, we provide an overview of the anti-obesity medications currently available for the long-term and individualized treatment of obesity.

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