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1.
Res Vet Sci ; 124: 256-262, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30999161

RESUMO

Interferon-induced proteins with tetratricopeptide repeats (IFITs) are a family of proteins strongly induced downstream of type I interferon signaling. The function of IFITs has been investigated extensively in mammals. IFIT5 is the sole protein in this family found in birds and little information is available about the function of avian IFIT5. In this study, duck IFIT5 was cloned from peripheral blood mononuclear cells. Multiple amino acid sequence alignment and phylogenetic analysis showed that duck IFIT5 is highly homologous to chicken IFIT5. Tissue specificity analysis demonstrated that duck IFIT5 was ubiquitously expressed in all examined tissues of five-day-old ducklings, with the highest expression levels in heart, followed by thymus, cerebrum, liver, and lung; kidney expressed the lowest. Quantitative real-time PCR (qRT-PCR) analysis revealed that duck IFIT5 expression rapidly increased both in vitro and in vivo after stimulation with polyinosinic:polycytidylic acid [poly (I:C)] and infection with virulent duck hepatitis A virus type 3 (DHAV-3), respectively. Altogether, these results indicate that the expression of duck IFIT5 is positively correlated with viral load and may play an important role in the immune response to DHAV-3 infection. This study lays a foundation for further research into the innate antiviral immune responses of ducklings.


Assuntos
Patos/genética , Patos/imunologia , Proteínas de Neoplasias/genética , Sequência de Aminoácidos , Animais , Animais Recém-Nascidos/genética , Animais Recém-Nascidos/imunologia , Proteínas Aviárias/química , Proteínas Aviárias/genética , Proteínas Aviárias/metabolismo , Sequência de Bases , Clonagem Molecular , Vírus da Hepatite do Pato/fisiologia , Hepatite Viral Animal/imunologia , Proteínas de Neoplasias/química , Proteínas de Neoplasias/metabolismo , Fases de Leitura Aberta , Filogenia , Infecções por Picornaviridae/imunologia , Infecções por Picornaviridae/veterinária , Poli I-C/farmacologia , Doenças das Aves Domésticas/imunologia , Alinhamento de Sequência
2.
Molecules ; 24(8)2019 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-31013622

RESUMO

G-quadruplex (G4) DNA secondary structures formed in human telomeres have been shown to inhibit cancer-specific telomerase and alternative lengthening of telomere (ALT) pathways. Thus, human telomeric G-quadruplexes are considered attractive targets for anticancer drugs. Human telomeric G-quadruplexes are structurally polymorphic and predominantly form two hybrid-type G-quadruplexes, namely hybrid-1 and hybrid-2, under physiologically relevant solution conditions. To date, only a handful solution structures are available for drug complexes of human telomeric G-quadruplexes. In this review, we will describe two recent solution structural studies from our labs. We use NMR spectroscopy to elucidate the solution structure of a 1:1 complex between a small molecule epiberberine and the hybrid-2 telomeric G-quadruplex, and the structures of 1:1 and 4:2 complexes between a small molecule Pt-tripod and the hybrid-1 telomeric G-quadruplex. Structural information of small molecule complexes can provide important information for understanding small molecule recognition of human telomeric G-quadruplexes and for structure-based rational drug design targeting human telomeric G-quadruplexes.


Assuntos
Quadruplex G , Proteínas de Neoplasias/química , Telomerase/química , Homeostase do Telômero , Telômero/química , Humanos , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/metabolismo , Ressonância Magnética Nuclear Biomolecular , Telomerase/antagonistas & inibidores , Telomerase/metabolismo , Telômero/metabolismo
3.
Mol Med Rep ; 19(5): 4433-4440, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30942454

RESUMO

MicroRNAs (miRNAs) are post­transcriptional regulators that mediate the initiation and progression of human cancer. Growing evidence suggests that deregulation of miRNA expression levels underlies chemo­resistance. To investigate whether miRNA­302a (miR­302a) is involved in mediating chemo­resistance to paclitaxel in prostate cancer, a series of in vitro analyses were performed in paclitaxel­resistant prostate cancer PC­3PR cells and non­resistant prostate cancer PC­3 cells. It was demonstrated that the expression of miR­302a was upregulated in PC­3PR cells. Notably, ectopic expression of miR­302a also increased resistance to paclitaxel in wild­type PC­3 cells. By contrast, silencing of miR­302a in PC­3PR cells sensitized the cells to paclitaxel. Gene and protein expression analyses suggested that the miR­302a target gene breast cancer resistance protein (BCRP) may mediate chemo­resistance to paclitaxel in PC­3PR cells. In conclusion, the data suggested that elevated miR­302a levels, in part, mediate sensitivity to paclitaxel in prostate cancer through the aberrant regulation of its downstream targets, AOF2, BCRP and permeability glycoprotein 1. These data have implications for the development of novel therapeutics in prostate cancer that may improve sensitivity to chemotherapeutics.


Assuntos
Resistencia a Medicamentos Antineoplásicos , MicroRNAs/metabolismo , Subfamília B de Transportador de Cassetes de Ligação de ATP/química , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/química , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Antagomirs/metabolismo , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Histona Desmetilases/química , Histona Desmetilases/genética , Histona Desmetilases/metabolismo , Humanos , Pontos de Checagem da Fase M do Ciclo Celular/efeitos dos fármacos , Masculino , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Proteínas de Neoplasias/química , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Paclitaxel/farmacologia , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Regulação para Cima
4.
Gene ; 701: 169-172, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-30930227

RESUMO

Therapeutic inhibition of hypoxia inducible factor-1α (HIF-1α) action has emerged as a potential approach for managing several diseases including breast cancer (BC). Genistein has been found to exert anti-malignant activity. However, its mechanisms of action remain unknown. Studies indicate that it could act by downregulating HIF-1α. Based on these findings, we investigated whether genistein could reduce HIF-1α in BC cell lines. Furthermore, we performed molecular docking studies to characterize the sites of interaction between genistein and HIF-1α. In the present investigation, we prove, for the first time, that genistein downregulates HIF-1α in BC cells. Molecular docking analysis also revealed that genistein binds to the FIH-1 binding site of HIF-1α protein. These findings thus indicate that genistein and/or HIF-1α antagonists could be a potential treatment for BC.


Assuntos
Neoplasias da Mama/química , Genisteína/química , Subunidade alfa do Fator 1 Induzível por Hipóxia/química , Simulação de Acoplamento Molecular , Proteínas de Neoplasias/química , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Domínio Catalítico , Linhagem Celular Tumoral , Regulação para Baixo , Feminino , Regulação Neoplásica da Expressão Gênica , Genisteína/farmacologia , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/biossíntese , Proteínas de Neoplasias/biossíntese
5.
Int J Mol Sci ; 20(4)2019 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-30813351

RESUMO

Estrogen receptor alpha (ERα) has an established role in breast cancer biology. Transcriptional activation by ERα is a multistep process modulated by coactivator and corepressor proteins. Breast Cancer Amplified Sequence 2 (BCAS2), is a poorly studied ERα coactivator. In this work, we characterize some of the mechanisms through which this protein increases ERα activity and how this promotes carcinogenic processes in breast cancer cells. Using protein-protein interaction and luciferase assays we show that BCAS2 interacts with ERα both in vitro and in vivo and upregulates transcriptional activation of ERα directly through its N-terminal region (AF-1) and indirectly through its C-terminal (AF-2) region, acting in concert with AF-2 interacting coactivators. Elevated expression of BCAS2 positively affects proliferation, clonogenicity and migration of breast cancer cells and directly activates ERα regulated genes which have been shown to play a role in tumor growth and progression. Finally, we used signal transduction pathway inhibitors to elucidate how BCAS2 is regulated in these cells and observed that BCAS2 is preferentially regulated by the PI3K/AKT signaling pathway. BCAS2 is an AF-1 coactivator of ERα whose overexpression promotes carcinogenic processes, suggesting an important role in the development of estrogen-receptor positive breast cancer.


Assuntos
Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Carcinogênese/metabolismo , Carcinogênese/patologia , Receptor alfa de Estrogênio/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Estradiol/farmacologia , Receptor alfa de Estrogênio/química , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Proteínas de Neoplasias/química , Regiões Promotoras Genéticas/genética , Ligação Proteica/efeitos dos fármacos , Transdução de Sinais , Transcrição Genética/efeitos dos fármacos , Ensaio Tumoral de Célula-Tronco
6.
Science ; 364(6435)2019 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-30872533

RESUMO

Inflammasomes are multiprotein platforms that initiate innate immunity by recruitment and activation of caspase-1. The NLRP1B inflammasome is activated upon direct cleavage by the anthrax lethal toxin protease. However, the mechanism by which cleavage results in NLRP1B activation is unknown. In this study, we find that cleavage results in proteasome-mediated degradation of the amino-terminal domains of NLRP1B, liberating a carboxyl-terminal fragment that is a potent caspase-1 activator. Proteasome-mediated degradation of NLRP1B is both necessary and sufficient for NLRP1B activation. Consistent with our functional degradation model, we identify IpaH7.8, a Shigella flexneri ubiquitin ligase secreted effector, as an enzyme that induces NLRP1B degradation and activation. Our results provide a unified mechanism for NLRP1B activation by diverse pathogen-encoded enzymatic activities.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Antígenos de Bactérias/metabolismo , Proteínas Reguladoras de Apoptose/metabolismo , Proteínas de Bactérias/metabolismo , Interações Hospedeiro-Patógeno/imunologia , Imunidade Inata , Inflamassomos/imunologia , Peptídeo Hidrolases/metabolismo , Proteólise , Shigella flexneri/patogenicidade , Ubiquitina-Proteína Ligases/metabolismo , Animais , Bacillus anthracis/enzimologia , Toxinas Bacterianas/metabolismo , Proteínas Adaptadoras de Sinalização CARD/química , Proteínas Adaptadoras de Sinalização CARD/metabolismo , Caspase 1/metabolismo , Proteínas Adaptadoras de Sinalização de Receptores de Domínio de Morte/química , Proteínas Adaptadoras de Sinalização de Receptores de Domínio de Morte/metabolismo , Ativação Enzimática , Células HEK293 , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Proteínas de Neoplasias/química , Proteínas de Neoplasias/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Domínios Proteicos , Subunidades Proteicas , Células RAW 264.7 , Shigella flexneri/enzimologia
7.
PLoS Comput Biol ; 15(3): e1006658, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30921324

RESUMO

At the root of the so-called precision medicine or precision oncology, which is our focus here, is the hypothesis that cancer treatment would be considerably better if therapies were guided by a tumor's genomic alterations. This hypothesis has sparked major initiatives focusing on whole-genome and/or exome sequencing, creation of large databases, and developing tools for their statistical analyses-all aspiring to identify actionable alterations, and thus molecular targets, in a patient. At the center of the massive amount of collected sequence data is their interpretations that largely rest on statistical analysis and phenotypic observations. Statistics is vital, because it guides identification of cancer-driving alterations. However, statistics of mutations do not identify a change in protein conformation; therefore, it may not define sufficiently accurate actionable mutations, neglecting those that are rare. Among the many thematic overviews of precision oncology, this review innovates by further comprehensively including precision pharmacology, and within this framework, articulating its protein structural landscape and consequences to cellular signaling pathways. It provides the underlying physicochemical basis, thereby also opening the door to a broader community.


Assuntos
Simulação por Computador , Mutação , Neoplasias/terapia , Medicina de Precisão , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Proteínas de Neoplasias/química , Proteínas de Neoplasias/metabolismo , Neoplasias/genética , Neoplasias/patologia , Conformação Proteica , Transdução de Sinais
8.
Nat Commun ; 10(1): 1151, 2019 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-30858376

RESUMO

The cell is constructed by higher-order structures and organelles through complex interactions among distinct structural constituents. The centrosome is a membraneless organelle composed of two microtubule-derived structures called centrioles and an amorphous mass of pericentriolar material. Super-resolution microscopic analyses in various organisms revealed that diverse pericentriolar material proteins are concentrically localized around a centriole in a highly organized manner. However, the molecular nature underlying these organizations remains unknown. Here we show that two human pericentriolar material scaffolds, Cep63 and Cep152, cooperatively generate a heterotetrameric α-helical bundle that functions in conjunction with its neighboring hydrophobic motifs to self-assemble into a higher-order cylindrical architecture capable of recruiting downstream components, including Plk4, a key regulator for centriole duplication. Mutations disrupting the self-assembly abrogate Plk4-mediated centriole duplication. Because pericentriolar material organization is evolutionarily conserved, this work may offer a paradigm for investigating the assembly and function of centrosomal scaffolds in various organisms.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Centríolos/metabolismo , Proteínas de Neoplasias/metabolismo , Multimerização Proteica/fisiologia , Proteínas Serina-Treonina Quinases/metabolismo , Motivos de Aminoácidos/genética , Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/isolamento & purificação , Linhagem Celular Tumoral , Cristalografia por Raios X , Células HEK293 , Humanos , Interações Hidrofóbicas e Hidrofílicas , Microscopia de Fluorescência , Mutação , Proteínas de Neoplasias/química , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/isolamento & purificação , Conformação Proteica em alfa-Hélice , Proteínas Serina-Treonina Quinases/isolamento & purificação , RNA Interferente Pequeno/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Imagem com Lapso de Tempo
9.
Proc Natl Acad Sci U S A ; 116(14): 6790-6799, 2019 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-30894480

RESUMO

While cells within tissues generate and sense 3D states of strain, the current understanding of the mechanics of fibrous extracellular matrices (ECMs) stems mainly from uniaxial, biaxial, and shear tests. Here, we demonstrate that the multiaxial deformations of fiber networks in 3D cannot be inferred solely based on these tests. The interdependence of the three principal strains gives rise to anomalous ratios of biaxial to uniaxial stiffness between 8 and 9 and apparent Poisson's ratios larger than 1. These observations are explained using a microstructural network model and a coarse-grained constitutive framework that predicts the network Poisson effect and stress-strain responses in uniaxial, biaxial, and triaxial modes of deformation as a function of the microstructural properties of the network, including fiber mechanics and pore size of the network. Using this theoretical approach, we found that accounting for the Poisson effect leads to a 100-fold increase in the perceived elastic stiffness of thin collagen samples in extension tests, reconciling the seemingly disparate measurements of the stiffness of collagen networks using different methods. We applied our framework to study the formation of fiber tracts induced by cellular forces. In vitro experiments with low-density networks showed that the anomalous Poisson effect facilitates higher densification of fibrous tracts, associated with the invasion of cancerous acinar cells. The approach developed here can be used to model the evolving mechanics of ECM during cancer invasion and fibrosis.


Assuntos
Carcinoma de Células Acinares , Colágeno , Matriz Extracelular , Modelos Moleculares , Proteínas de Neoplasias , Animais , Carcinoma de Células Acinares/química , Carcinoma de Células Acinares/metabolismo , Carcinoma de Células Acinares/patologia , Linhagem Celular Tumoral , Colágeno/química , Colágeno/metabolismo , Matriz Extracelular/química , Matriz Extracelular/metabolismo , Humanos , Proteínas de Neoplasias/química , Proteínas de Neoplasias/metabolismo , Ratos
10.
Proc Natl Acad Sci U S A ; 116(15): 7278-7287, 2019 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-30910957

RESUMO

Mucin domains are densely O-glycosylated modular protein domains that are found in a wide variety of cell surface and secreted proteins. Mucin-domain glycoproteins are known to be key players in a host of human diseases, especially cancer, wherein mucin expression and glycosylation patterns are altered. Mucin biology has been difficult to study at the molecular level, in part, because methods to manipulate and structurally characterize mucin domains are lacking. Here, we demonstrate that secreted protease of C1 esterase inhibitor (StcE), a bacterial protease from Escherichia coli, cleaves mucin domains by recognizing a discrete peptide- and glycan-based motif. We exploited StcE's unique properties to improve sequence coverage, glycosite mapping, and glycoform analysis of recombinant human mucins by mass spectrometry. We also found that StcE digests cancer-associated mucins from cultured cells and from ascites fluid derived from patients with ovarian cancer. Finally, using StcE, we discovered that sialic acid-binding Ig-type lectin-7 (Siglec-7), a glycoimmune checkpoint receptor, selectively binds sialomucins as biological ligands, whereas the related receptor Siglec-9 does not. Mucin-selective proteolysis, as exemplified by StcE, is therefore a powerful tool for the study of mucin domain structure and function.


Assuntos
Antígenos CD/química , Antígenos de Diferenciação Mielomonocítica/química , Proteínas de Escherichia coli/química , Escherichia coli/enzimologia , Lectinas/química , Metaloendopeptidases/química , Mucinas/química , Proteínas de Neoplasias/química , Lectinas Semelhantes a Imunoglobulina de Ligação ao Ácido Siálico/química , Motivos de Aminoácidos , Humanos , Espectrometria de Massas , Especificidade por Substrato
11.
In Vivo ; 33(2): 567-572, 2019 Mar-Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30804143

RESUMO

AIM: To investigate the molecular structural disorders of cancerous skin. MATERIALS AND METHODS: Human malignant melanoma and basal cell carcinoma biopsies were used for the investigation. Fourier transform infrared (FT-IR), Raman spectroscopy, and scanning electron microscopy were utilized. Spectral differences between healthy, basal cell carcinoma and melanoma tissues were recorded. RESULTS: The FT-IR bands of vasCH2, vsCH2 and Raman vsCH3 of cell membrane lipids were increased in intensity in melanoma due to an increased lipophilic environment. The FT-IR band at 1,744 cm-1 assigned to malondialdehyde can be used as a band diagnostic of cancer progression. The amide I bands at 1,654 cm-1 and 1,650 cm-1 for Raman and FT-IR, respectively were broader in spectra from melanoma, reflecting changes of protein secondary structure from α-helix to ß-sheet and random coil. The intensity of the FT-IR band at 1,046 cm-1 was increased in melanoma, suggesting glycosylation of the skin upon cancer development. Another band that might be considered as diagnostic was found at about 815 cm-1 in melanoma and was attributed to Z-DNA configuration. As far as we know, this is the first time that scanning electron microscopy revealed that metal components of titanium alloys from tooth implants were transferred to melanoma tissue taken from the back of one patient. CONCLUSION: Vibrational spectroscopy highlighted increased glycosylation in melanoma.


Assuntos
Carcinoma Basocelular/química , Melanoma/química , Proteínas de Neoplasias/química , Neoplasias Cutâneas/química , Idoso , Biópsia , Carcinoma Basocelular/patologia , Humanos , Malondialdeído/química , Melanoma/patologia , Pessoa de Meia-Idade , Estrutura Secundária de Proteína , Pele/química , Pele/patologia , Neoplasias Cutâneas/patologia , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman
12.
Acta Crystallogr F Struct Biol Commun ; 75(Pt 2): 73-79, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30713157

RESUMO

Programmed cell death 5 (PDCD5) is a vital signaling protein in the apoptosis pathway in eukaryotes. It is known that there are two dissociated N-terminal regions and a triple-helix core in eukaryotic PDCD5. Structural and functional studies of PDCD5 from hyperthermophilic archaea have been limited to date. Here, the PDCD5 homolog Sso0352 (SsoPDCD5) was identified in Sulfolobus solfataricus, the SsoPDCD5 protein was expressed and crystallized, and the phase was identified by single-wavelength anomalous diffraction. The native SsoPDCD5 crystal belonged to space group C2 and diffracted to 1.49 Šresolution. This is the first crystal structure of a PDCD5 homolog to be solved. SsoPDCD5 shares a similar triple-helix bundle with eukaryotic PDCD5 but has a long α-helix in the N-terminus. A structural search and biochemical data suggest that SsoPDCD5 may function as a DNA-binding protein.


Assuntos
Proteínas Reguladoras de Apoptose/química , Proteínas de Neoplasias/química , Sulfolobus solfataricus/enzimologia , Sequência de Aminoácidos , Proteínas Reguladoras de Apoptose/isolamento & purificação , Proteínas Reguladoras de Apoptose/metabolismo , Cristalização , Cristalografia por Raios X , Humanos , Modelos Moleculares , Proteínas de Neoplasias/isolamento & purificação , Proteínas de Neoplasias/metabolismo , Ligação Proteica , Conformação Proteica , Homologia de Sequência
13.
Chem Biol Interact ; 302: 74-82, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30738779

RESUMO

Accumulating evidence has suggested that microRNA-449b-5p (miR-449b-5p) plays an important role in the development and progression of multiple cancers. However, little is known about the role of miR-449b-5p in breast cancer. In this study, we aimed to investigate the expression level, biological function and underlying mechanism of miR-449b-5p in breast cancer. Our results showed that miR-449b-5p expression was frequently down-regulated in breast cancer cell lines and tissues. The overexpression of miR-449b-5p significantly inhibited growth and invasion, and induced the cell cycle arrest of breast cancer cells. In contrast, the inhibition of miR-449b-5p showed the opposite effect. Interestingly, bioinformatic analysis predicted that cell cycle-related and expression-elevated protein in tumor (CREPT), an important oncogene in breast cancer, was a potential target gene of miR-449b-5p. The overexpression of miR-449b-5p decreased CREPT expression while miR-449b-5p inhibition promoted CREPT expression in breast cancer cells. Restoration of CREPT expression in miR-449b-5p mimics transfected cells partially reversed the suppressive effect of miR-449b-5p on breast cancer cell growth and invasion. Notably, our results showed that miR-449b-5p overexpression decreased the expression of ß-catenin and suppressed the activation of Wnt/ß-catenin/TCF-4 signaling via targeting CREPT. In addition, blocking Wnt/ß-catenin partially reversed the promotion effect of miR-449b-5p inhibition on breast cancer cell growth and invasion. Overall, these results reveal a tumor suppressive role of miR-449b-5p that restricts the growth and invasion of breast cancer cells through targeting CREPT and inhibiting CREPT-mediated activation of Wnt/ß-catenin signaling. Our study suggests that the miR-449b-5p/CREPT/Wnt/ß-catenin axis may play an important role in the pathogenesis of breast cancer and miR-449-5p may serve as a potential therapeutic target for breast cancer.


Assuntos
Neoplasias da Mama/patologia , Proteínas de Ciclo Celular/metabolismo , MicroRNAs/metabolismo , Proteínas de Neoplasias/metabolismo , Via de Sinalização Wnt , Regiões 3' não Traduzidas , Antagomirs/metabolismo , Sítios de Ligação , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/genética , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Feminino , Humanos , Células MCF-7 , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Proteínas de Neoplasias/química , Proteínas de Neoplasias/genética , Fator de Transcrição 4/metabolismo , Proteínas Wnt/metabolismo , beta Catenina/metabolismo
14.
BMC Bioinformatics ; 20(1): 23, 2019 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-30642247

RESUMO

BACKGROUND: Clustering molecular network is a typical method in system biology, which is effective in predicting protein complexes or functional modules. However, few studies have realized that biological molecules are spatial-temporally regulated to form a dynamic cellular network and only a subset of interactions take place at the same location in cells. RESULTS: In this study, considering the subcellular localization of proteins, we first construct a co-localization human protein interaction network (PIN) and systematically investigate the relationship between subcellular localization and biological functions. After that, we propose a Locational and Topological Overlap Model (LTOM) to preprocess the co-localization PIN to identify functional modules. LTOM requires the topological overlaps, the common partners shared by two proteins, to be annotated in the same localization as the two proteins. We observed the model has better correspondence with the reference protein complexes and shows more relevance to cancers based on both human and yeast datasets and two clustering algorithms, ClusterONE and MCL. CONCLUSION: Taking into consideration of protein localization and topological overlap can improve the performance of module detection from protein interaction networks.


Assuntos
Algoritmos , Biologia Computacional/métodos , Bases de Dados de Proteínas , Proteínas de Neoplasias/metabolismo , Mapeamento de Interação de Proteínas/métodos , Mapas de Interação de Proteínas , Proteínas de Saccharomyces cerevisiae/metabolismo , Humanos , Proteínas de Neoplasias/química , Proteínas de Saccharomyces cerevisiae/química
15.
Int J Mol Sci ; 19(12)2018 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-30562979

RESUMO

Members of the aurora kinase family are Ser/Thr kinases involved in regulating mitosis. Multiple promising clinical trials to target aurora kinases are in development. To discover flavones showing growth inhibitory effects on cancer cells, 36 flavone derivatives were prepared, and their cytotoxicity was measured using a long-term clonogenic survival assay. Their half-maximal growth inhibitory effects against HCT116 human colon cancer cells were observed at the sub-micromolar level. Pharmacophores were derived based on three-dimensional quantitative structure⁻activity calculations. Because plant-derived flavones inhibit aurora kinase B, we selected 5-methoxy-2-(2-methoxynaphthalen-1-yl)-4H-chromen-4-one (derivative 31), which showed the best half-maximal cell growth inhibitory effect, and tested whether it can inhibit aurora kinases in HCT116 colon cancer cells. We found that derivative 31 inhibited the phosphorylation of aurora kinases A, aurora kinases B and aurora kinases C, suggesting that derivative 31 is a potential pan-aurora kinase inhibitor. The results of our analysis of the binding modes between derivative 31 and aurora A and aurora B kinases using in-silico docking were consistent with the pharmacophores proposed in this study.


Assuntos
Apoptose/efeitos dos fármacos , Aurora Quinases/antagonistas & inibidores , Neoplasias do Colo/enzimologia , Flavonas/farmacologia , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Pontos de Checagem da Fase M do Ciclo Celular/efeitos dos fármacos , Proteínas de Neoplasias/antagonistas & inibidores , Aurora Quinases/química , Aurora Quinases/genética , Aurora Quinases/metabolismo , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Flavonas/síntese química , Flavonas/química , Células HCT116 , Humanos , Simulação de Acoplamento Molecular , Proteínas de Neoplasias/química , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo
16.
Proc Natl Acad Sci U S A ; 115(40): 10016-10021, 2018 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-30224471

RESUMO

The MuvB transcriptional regulatory complex, which controls cell-cycle-dependent gene expression, cooperates with B-Myb to activate genes required for the G2 and M phases of the cell cycle. We have identified the domain in B-Myb that is essential for the assembly of the Myb-MuvB (MMB) complex. We determined a crystal structure that reveals how this B-Myb domain binds MuvB through the adaptor protein LIN52 and the scaffold protein LIN9. The structure and biochemical analysis provide an understanding of how oncogenic B-Myb is recruited to regulate genes required for cell-cycle progression, and the MMB interface presents a potential therapeutic target to inhibit cancer cell proliferation.


Assuntos
Proteínas de Ciclo Celular , Ciclo Celular , Complexos Multiproteicos , Proteínas de Neoplasias , Neoplasias , Proteínas Nucleares , Transativadores , Proteínas Supressoras de Tumor , Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular , Cristalografia por Raios X , Humanos , Complexos Multiproteicos/química , Complexos Multiproteicos/metabolismo , Proteínas de Neoplasias/química , Proteínas de Neoplasias/metabolismo , Neoplasias/química , Neoplasias/metabolismo , Proteínas Nucleares/química , Proteínas Nucleares/metabolismo , Domínios Proteicos , Transativadores/química , Transativadores/metabolismo , Proteínas Supressoras de Tumor/química , Proteínas Supressoras de Tumor/metabolismo
17.
Proc Natl Acad Sci U S A ; 115(30): E7119-E7128, 2018 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-29976840

RESUMO

Sal-like 4 (SALL4) is a nuclear factor central to the maintenance of stem cell pluripotency and is a key component in hepatocellular carcinoma, a malignancy with no effective treatment. In cancer cells, SALL4 associates with nucleosome remodeling deacetylase (NuRD) to silence tumor-suppressor genes, such as PTEN. Here, we determined the crystal structure of an amino-terminal peptide of SALL4(1-12) complexed to RBBp4, the chaperone subunit of NuRD, at 2.7 Å, and subsequent design of a potent therapeutic SALL4 peptide (FFW) capable of antagonizing the SALL4-NURD interaction using systematic truncation and amino acid substitution studies. FFW peptide disruption of the SALL4-NuRD complex resulted in unidirectional up-regulation of transcripts, turning SALL4 from a dual transcription repressor-activator mode to singular transcription activator mode. We demonstrate that FFW has a target affinity of 23 nM, and displays significant antitumor effects, inhibiting tumor growth by 85% in xenograft mouse models. Using transcriptome and survival analysis, we discovered that the peptide inhibits the transcription-repressor function of SALL4 and causes massive up-regulation of transcripts that are beneficial to patient survival. This study supports the SALL4-NuRD complex as a drug target and FFW as a viable drug candidate, showcasing an effective strategy to accurately target oncogenes previously considered undruggable.


Assuntos
Antineoplásicos , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas de Neoplasias , Neoplasias , Peptídeos , Fatores de Transcrição , Transcriptoma/efeitos dos fármacos , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Humanos , Proteínas de Neoplasias/química , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Neoplasias/química , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias/metabolismo , Peptídeos/química , Peptídeos/farmacologia , Estrutura Quaternária de Proteína , Proteína 4 de Ligação ao Retinoblastoma/química , Proteína 4 de Ligação ao Retinoblastoma/genética , Proteína 4 de Ligação ao Retinoblastoma/metabolismo , Fatores de Transcrição/química , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
18.
Zhonghua Zhong Liu Za Zhi ; 40(5): 359-364, 2018 May 23.
Artigo em Chinês | MEDLINE | ID: mdl-29860763

RESUMO

Objective: To investigate the expressions of migration and invasion inhibitory protein (MIIP) and p21-activated kinase 1 (PAK1) in endometrial carcinoma (EC) and their correlation with clinicopathological features. Methods: The protein levels of MIIP and PAK1 in 135 paraffin-embedded EC tissues, 55 atypical hyperplasia of endometrium (AHE) and 88 normal endometrium (NE) tissues were quantified by immunohistochemistry, the clincial significance and the relationship of these two proteins were also analyzed. Results: The positive rates of MIIP expression in NE, AHE and EC tissues were 52.3%(46/88), 41.8% (23/55) and 34.8% (47/135), respectively. The expression of MIIP in EC was significantly lower than that of MIIP in NE (P<0.05). The positive rates of PAK1 expression in NE, AHE and EC tissues were 45.5% (40/88), 50.9% (28/55) and 62.2% (84/135), respectively. The expression of PAK1 in EC tissues was significantly higher than that of PAK1 in NE tissues (P<0.05). The expression of MIIP in EC tissues was significantly associated with myometrial invasion, International Federation of Gynaecology and Obstetrics (FIGO) stage and lymph node metastasis (P<0.05). The expression of PAK1 in EC tissues was significantly related with differentiation, myometrial invasion, FIGO stage and lymph node metastasis (P<0.05). The expressions of MIIP and PAK1 in EC tissues were marginally related with the overall survival of patients (P=0.092, P=0.052). The expression of MIIP in EC was negatively correlated with PAK1 (r=-0.329, P<0.001). Conclusions: The down-regulation of MIIP and up-regualtion of PAK1 paticipate in the initiation and development of EC, which are correlated with the poor prognosis of EC. The protein expression of MIIP is inversely related with PAK1 in EC.


Assuntos
Proteínas de Transporte/análise , Neoplasias do Endométrio/química , Endométrio/química , Proteínas de Neoplasias/química , Quinases Ativadas por p21/análise , Neoplasias do Endométrio/mortalidade , Feminino , Humanos , Imuno-Histoquímica , Metástase Linfática , Prognóstico
19.
Clin Biochem ; 58: 108-115, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29928903

RESUMO

OBJECTIVE: Human tissue kallikrein 15 (KLK15) is the last cloned member of the KLK-related gene family. Despite being implicated in multiple cancers, its pathophysiological role remains unknown. We aimed to biochemically characterize KLK15 and preliminarily study its role in cancer. DESIGN & METHODS: Recombinant KLK15 protein was produced, purified to homogeneity and quantified by mass spectrometry (parallel reaction monitoring analysis). We profiled the enzymatic activity of KLK15 using fluorogenic peptide substrates, and performed kinetic analysis to discover the cleavage sites. As KLK15 has mainly been associated with prostate cancer, we used a degradomic approach and subsequent KEGG pathway analysis to identify a number of putative protein substrates in the KLK15-treated prostate cancer cell line PC3. RESULTS: We discovered trypsin-like activity in KLK15, finding that it cleaves preferentially after arginine (R). The enzymatic activity of KLK15 was regulated by different factors such as pH, cations and serine protease inhibitors. Notably, we revealed that KLK15 most likely interacts with the extracellular matrix (ECM) receptor group. CONCLUSION: To our knowledge, this is the first study that experimentally verifies the trypsin-like activity of KLK15. We show here for the first time that KLK15 may be able to cleave many ECM components, similar to several members of the KLK family. Thus the protease could potentially be linked to tumorigenesis by promoting metastasis via this mechanism.


Assuntos
Matriz Extracelular/enzimologia , Calicreínas/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias da Próstata/enzimologia , Linhagem Celular , Matriz Extracelular/genética , Matriz Extracelular/patologia , Humanos , Calicreínas/química , Calicreínas/genética , Masculino , Metástase Neoplásica , Proteínas de Neoplasias/química , Proteínas de Neoplasias/genética , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
20.
Proc Natl Acad Sci U S A ; 115(26): 6792-6797, 2018 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-29891674

RESUMO

The inflammasomes are signaling platforms that promote the activation of inflammatory caspases such as caspases-1, -4, -5, and -11. Recent studies identified gasdermin D (GSDMD) as an effector for pyroptosis downstream of the inflammasome signaling pathways. Cleavage of GSDMD by inflammatory caspases allows its N-terminal domain to associate with membrane lipids and form pores that induce pyroptotic cell death. Despite the important role of GSDMD in pyroptosis, the molecular mechanisms of GSDMD recognition and cleavage by inflammatory caspases that trigger pyroptosis are poorly understood. Here, we demonstrate that the catalytic domains of inflammatory caspases can directly bind to both the full-length GSDMD and its cleavage site peptide, FLTD. A GSDMD-derived inhibitor, N-acetyl-Phe-Leu-Thr-Asp-chloromethylketone (Ac-FLTD-CMK), inhibits GSDMD cleavage by caspases-1, -4, -5, and -11 in vitro, suppresses pyroptosis downstream of both canonical and noncanonical inflammasomes, as well as reduces IL-1ß release following activation of the NLRP3 inflammasome in macrophages. By contrast, the inhibitor does not target caspase-3 or apoptotic cell death, suggesting that Ac-FLTD-CMK is a specific inhibitor for inflammatory caspases. Crystal structure of caspase-1 in complex with Ac-FLTD-CMK reveals extensive enzyme-inhibitor interactions involving both hydrogen bonds and hydrophobic contacts. Comparison with other caspase-1 structures demonstrates drastic conformational changes at the four active-site loops that assemble the catalytic groove. The present study not only contributes to our understanding of GSDMD recognition by inflammatory caspases but also reports a specific inhibitor for these caspases that can serve as a tool for investigating inflammasome signaling.


Assuntos
Proteínas Reguladoras de Apoptose/química , Inibidores de Caspase/química , Proteínas de Neoplasias/química , Peptídeos/química , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Caspase 3/química , Caspase 3/metabolismo , Inibidores de Caspase/metabolismo , Domínio Catalítico , Células HEK293 , Humanos , Células Jurkat , Camundongos , Proteínas de Neoplasias/metabolismo , Peptídeos/metabolismo , Estrutura Secundária de Proteína , Células RAW 264.7 , Células THP-1
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