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1.
Clin. transl. oncol. (Print) ; 18(1): 65-72, ene. 2016. tab, ilus
Artigo em Inglês | IBECS | ID: ibc-148053

RESUMO

Objective. The aim of the this study was to analyze the status of sex-determining region Y-related high-mobility group box 4 (SOX4) expression in varied human cancers and its correlation with overall survival in patients with human cancers. Methods. To observe initially the expression status of SOX4 in twenty kinds of human cancers at protein database (The Human Protein Atlas). We systematically and carefully searched the studies from electronic databases and seriously identified according to eligibility criteria. The correlation between SOX4 expression and overall survival in human cancers was evaluated through Review Manager. Results. We found that SOX4 expression was significantly positive in most types of human cancer tissues, and the positive rate of SOX4 expression was about 78 % in overall cancer tissues. Furthermore, a total of 10 studies which included 1348 cancer patients were included in the final analysis. Meta-analysis showed that SOX4 overexpression was correlated with a poor overall survival and the pooled hazard ratio (HR), and corresponding 95 % confidence interval (CI) was 1.67 (95 % CI 1.01-2.78). From subgroup analyses, we present evidence that SOX4 overexpression was an unfavorable prognostic factor for colorectal cancer patients’ recurrence-free survival and gastric cancer patients’ overall survival, and the pooled HRs (95 % CI) were 1.73 (95 % CI 1.04-2.88) and 3.74 (95 % CI 1.04-13.45), respectively. Conclusions. In summary, SOX4 is a potential prognostic biomarker in human cancers (AU)


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Assuntos
Humanos , Masculino , Feminino , Fatores de Transcrição SOX/administração & dosagem , Fatores de Transcrição SOX/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , Bases de Dados como Assunto , Neoplasias do Colo do Útero/diagnóstico , Neoplasias Hepáticas/patologia , Tumor Carcinoide/complicações , Neoplasias Colorretais/metabolismo , Fatores de Transcrição SOX , Fatores de Transcrição SOX/provisão & distribuição , Neoplasias/tratamento farmacológico , Neoplasias/radioterapia , Bases de Dados como Assunto , Neoplasias do Colo do Útero/complicações , Neoplasias Hepáticas/metabolismo , Tumor Carcinoide/diagnóstico , Neoplasias Colorretais/diagnóstico
2.
Parasitology ; 141(4): 570-8, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24477026

RESUMO

Glutathione peroxidase (GPx; EC 1.11.1.9) is an important antioxidant enzyme that catalyses the reduction of organic and inorganic hydroperoxides to water in oxygen-consuming organisms, using glutathione as an electron donor. Here, we report the characterization of a GPx of Cryptosporidium parvum (CpGPx). CpGPx contained a standard UGU codon for cysteine instead of a UGA opal codon for seleno-cysteine (SeCys) at the active site, and no SeCys insertion sequence (SECIS) motif was identified within the 3'-untranslated region (UTR) of CpGPx, which suggested its selenium-independent nature. In silico and biochemical analyses indicated that CpGPx is a cytosolic protein with a monomeric structure. Recombinant CpGPx was active over a wide pH range and was stable under physiological conditions. It showed a substrate preference against organic hydroperoxides, such as cumene hydroperoxide and t-butyl hydroperoxide, but it also showed activity against inorganic hydroperoxide, hydrogen peroxide. Recombinant CpGPx was not inhibited by potassium cyanide or by sodium azide. The enzyme effectively protected DNA and protein from oxidative damage induced by hydrogen peroxide, and was functionally expressed in various developmental stages of C. parvum. These results collectively suggest the essential role of CpGPx for the parasite's antioxidant defence system.


Assuntos
Anticorpos Antiprotozoários/imunologia , Criptosporidiose/parasitologia , Cryptosporidium parvum/enzimologia , Glutationa Peroxidase/metabolismo , Sequência de Aminoácidos , Animais , Antioxidantes/metabolismo , Cryptosporidium parvum/efeitos dos fármacos , Cryptosporidium parvum/genética , Cryptosporidium parvum/imunologia , Citosol/enzimologia , Glutationa/metabolismo , Glutationa Peroxidase/genética , Humanos , Peróxido de Hidrogênio/farmacologia , Dados de Sequência Molecular , Oxirredução , Estresse Oxidativo , Filogenia , Cianeto de Potássio/farmacologia , Estrutura Terciária de Proteína , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Proteínas Recombinantes , Alinhamento de Sequência , Azida Sódica/farmacologia
3.
Parasitology ; 139(8): 1029-37, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22444160

RESUMO

Cysteine proteases of pathogenic protozoan parasites play pivotal roles in the life cycle of parasites, but strict regulation of their activities is also essential for maintenance of parasite physiology and interaction with hosts. In this study, we identified and characterized cryptostatin, a novel inhibitor of cysteine protease (ICP) of Cryptosporidium parvum. Cryptostatin showed low sequence identity to other chagasin-family ICPs, but 3 motifs (NPTTG, GXGG, and RPW/F motifs), which are evolutionarily conserved in chagasin-family ICPs, were found in the sequence. The overall structure of cryptostatin consisted of 8 ß-strands that progressed in parallel and closely resembled the immunoglobulin fold. Recombinant cryptostatin inhibited various cysteine proteases, including papain, human cathepsin B, human cathepsin L, and cryptopain-1, with K i's in the picomolar range. Cryptostatin was active over a wide pH range and was highly stable under physiological conditions. The protein was thermostable and retained its inhibitory activity even after incubation at 95°C. Cryptostatin formed tight complexes with cysteine proteases, so the complexes remained intact in the presence of sodium dodecyl sulfate and ß-mercaptoethanol, but they were disassembled by boiling. An immunogold electron microscopy analysis demonstrated diffused localization of cryptostatin within oocystes and meronts, but not within trophozoites, which suggests a possible role for cryptostatin in host cell invasion by C. parvum.


Assuntos
Cryptosporidium parvum/genética , Cistatinas/química , Cisteína Proteases/metabolismo , Inibidores de Cisteína Proteinase/química , Proteínas de Protozoários/metabolismo , Motivos de Aminoácidos , Catepsina B/antagonistas & inibidores , Catepsina B/química , Catepsina L/antagonistas & inibidores , Catepsina L/química , Cryptosporidium parvum/metabolismo , Cistatinas/genética , Cistatinas/metabolismo , Cisteína Proteases/química , Cisteína Proteases/genética , Inibidores de Cisteína Proteinase/genética , Inibidores de Cisteína Proteinase/metabolismo , Temperatura Alta , Humanos , Cinética , Modelos Moleculares , Dados de Sequência Molecular , Papaína/antagonistas & inibidores , Papaína/química , Estabilidade Proteica , Estrutura Secundária de Proteína , Proteínas de Protozoários/química , Proteínas de Protozoários/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência
4.
Parasitology ; 138(6): 682-90, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21414242

RESUMO

Leucine aminopeptidases (LAPs) are a group of metalloexopeptidases that catalyse the sequential removal of amino acids from the N-termini of polypeptides or proteins. They play an important role in regulating the balance between catabolism and anabolism in living cells. LAPs of apicomplexa parasitic protozoa have been intensively investigated due to their crucial roles in parasite biology as well as their potentials as drug targets. In this study, we identified an M17 leucine aminopeptidase of Cryptosporidium parvum (CpLAP) and characterized the biochemical properties of the recombinant protein. Multiple sequence alignment of the deduced amino acid sequence of CpLAP with those of other organisms revealed that typical amino acid residues essential for metal binding and active-site formation in M17 LAPs were well conserved in CpLAP. Recombinant CpLAP shared similar biochemical properties such as optimal pH, stability at neutral pHs, and metal-binding characteristics with other characterized LAPs. The enzyme showed a marked preference for Leu and its activity was effectively inhibited by bestatin. These results collectively suggest that CpLAP is a typical member of the M17 LAP family and may play an important role in free amino acid regulation in the parasite.


Assuntos
Cryptosporidium parvum/enzimologia , Cryptosporidium parvum/genética , Leucil Aminopeptidase/genética , Leucil Aminopeptidase/metabolismo , Sequência de Aminoácidos , Quelantes/farmacologia , Clonagem Molecular , Cryptosporidium parvum/classificação , Ácido Edético/farmacologia , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Leucil Aminopeptidase/química , Metais/farmacologia , Dados de Sequência Molecular , Filogenia , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Especificidade por Substrato
9.
Phys Rev B Condens Matter ; 48(2): 1112-1118, 1993 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-10007970
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