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1.
Oncotarget ; 8(52): 89887-89902, 2017 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-29163796

RESUMO

In the present study, the therapeutic potential of targeting plasminogen activator inhibitor-1 (PAI-1) in ovarian cancer was tested. Tissues samples from 154 cases of ovarian carcinoma were immunostained with anti-PAI-1 antibody, and the prognostic value was analyzed. Among the samples, 67% (104/154) showed strong PAI-1 expression; this was significantly associated with poor prognosis (progression-free survival: 20 vs. 31 months, P = 0.0033). In particular, among patients with stage II-IV serous adenocarcinoma, PAI-1 expression was an independent prognostic factor. The effect of a novel PAI-1 inhibitor, IMD-4482, on ovarian cancer cell lines was assessed and its therapeutic potential was examined using a xenograft mouse model of ovarian cancer. IMD-4482 inhibited in vitro cell adhesion to vitronectin in PAI-1-positive ovarian cancer cells, followed by the inhibition of extracellular signal-regulated kinase and focal adhesion kinase phosphorylation through dissociation of the PAI-urokinase receptor complex from integrin αVß3. IMD-4482 caused G0/G1 cell arrest and inhibited the proliferation of PAI-1-positive ovarian cancer cells. In the xenograft model, IMD-4482 significantly inhibited peritoneal dissemination with the reduction of PAI-1 expression and the inhibition of focal adhesion kinase phosphorylation. Collectively, the functional inhibition of PAI-1 significantly inhibited ovarian cancer progression, and targeting PAI-1 may be a potential therapeutic strategy in ovarian cancer.

2.
Biotechnol Appl Biochem ; 64(3): 385-391, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27028566

RESUMO

Aspergillus oryzae is a fungus widely used in traditional Japanese fermentation industries. Cytochrome P450 (CYP) proteins are ubiquitously distributed in nature and display a broad range of enzymatic activities. A novel CYP52 (CYP52G3) gene was found in A. oryzae. In this study, we report the functional characterization of CYP52G3. The recombinant protein was expressed heterologously in Escherichia coli, and its membrane fraction isolated. CYP52G3 showed activities for 7-ethoxycoumarin and α-naphtoflavone. Furthermore, CYP52G3 hydroxylated flavanone at the 4' and 6 position and metabolized some hydroxyl-flavanones and steroids. Bioconversion experiments indicated that CYP52G3 could convert flavanone and testosterone in a synthetic medium. The conversion rates of flavanone and testosterone at 24 H were 50% and 70%, respectively. These results support that CYP52G3 could prove a useful enzyme for the efficient production of new compounds from flavonoids and steroids.


Assuntos
Aspergillus oryzae/enzimologia , Sistema Enzimático do Citocromo P-450/química , Flavanonas/química , Proteínas Fúngicas/química , Testosterona/química
3.
Environ Toxicol Pharmacol ; 40(2): 360-8, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26233561

RESUMO

We evaluated the metabolism of several herbicides and progesterone by two P450 proteins (CYP1A9 and CYP1C1) from Japanese eel (Anguilla japonica). Expression vectors harboring CYP1A9 and CYP1C1 sequences were introduced into Escherichia coli. E. coli membrane fractions were incubated with each substrate, and the metabolites were analyzed. CYP1A9 and CYP1C1 deethylated 7-ethoxycoumarin and phenacetin, and demethylated chlorotoluron, diuron, and linuron. CYP1C1 specifically hydroxlyated progesterone at the 6ß and 16α positions. Five amino acids of CYP1A9 related to substrate binding were selected for mutation analyses [CYP1A9(F128A), CYP1A9(F229A), CYP1A9(F263A), CYP1A9(V387A), and CYP1A9(I391A)]. Two variants, CYP1A9(F229A) and CYP1A9(F128A), changed the ratio of 16α hydroxyprogesterone to 6ß hydroxyprogesterone. Among all the variants, CYP1A9(F263A) showed the highest activity towards substrates used. CYP1A9(V387A) and CYP1A9(I391A) showed higher activities than that of CYP1A9 toward progesterone. The substrate specificity of CYP1A9 may be altered by replacing an amino acid related to substrate binding.


Assuntos
Anguilla/genética , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Animais , Sítios de Ligação , Cumarínicos/metabolismo , Sistema Enzimático do Citocromo P-450/química , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Peixes/química , Mutação , Fenacetina/metabolismo , Progesterona/metabolismo , Especificidade por Substrato
4.
Biopharm Drug Dispos ; 36(8): 552-63, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26222491

RESUMO

CYP2A6 is a major hepatic member of the cytochrome P450 family in humans. Much variation in CYP2A6 levels and activity can be attributed to genetic polymorphisms of this gene. CYP2A6*25 comprises an amino acid substitution, F118L. To clarify the effect of the leucine substitution at position 118 in CYP2A6.25, this variant, wild type CYP2A6 and three additional variants consisting of artificial mutations at the substrate binding site (position 481) suggested by earlier reports using random mutagenesis studies [CYP2A6.1, CYP2A6.25, CYP2A6.1(F118A), CYP2A6.1(A481G) and CYP2A6.25(A481G)], were co-expressed with NADPH-cytochrome P450 reductase in E. coli. The hydroxylase activity of these variants toward 7-ethoxycoumarin, coumarin, flavone, α-naphthoflavone, flavanone and hydroxyflavanone were examined. All the mutants had lower activities for coumarin 7-hydroxylation than the wild type. All the mutants showed higher activities for flavone and α-naphthoflavone compared with CYP2A6.1. CYP2A6.1 had the highest flavanone 2'-hydroxylase activity, whereas CYP2A6.25 had the highest 6- and 4'-hydroxylase activities. CYP2A6.1(F118A), CYP2A6.1(A481G) and CYP2A6.25(A481G) had higher flavanone 3'-hydroxylase activities than CYP2A6.1 and CYP2A6.25. Furthermore, 4'-hydroxyflavanone was metabolized by CYP2A6.25. These results indicate that the CYP2A6.25 mutation confers new substrate specificity towards flavonoids.


Assuntos
Citocromo P-450 CYP2A6/genética , Citocromo P-450 CYP2A6/metabolismo , Flavonoides/metabolismo , Mutação Puntual , Polimorfismo de Nucleotídeo Único , Substituição de Aminoácidos , Sítios de Ligação , Cromatografia Líquida de Alta Pressão , Escherichia coli/genética , Hidroxilação , Especificidade por Substrato , Transfecção
5.
Leg Med (Tokyo) ; 15(6): 323-8, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24112990

RESUMO

The deceased was an unidentified young male found unconscious on a walkway. On autopsy, outer and inner fistulae of the left temporal bone, subcutaneous abscess in the left side of the neck and head, and an intracranial abscess were noted. A portion of the left temporal bone was removed and scanned by cone-beam computed tomography (CT) (normally used for dentistry applications) to evaluate the lesion. The cone-beam CT image revealed roughening of the bone wall and hypolucency of the mastoid air cells, consistent with an inflammatory bone lesion. According to autopsy and imaging findings, the cause of death was diagnosed as intracranial abscess with Bezold's abscess secondary to left mastoiditis as a complication of otitis media. Although determining the histopathology of bone specimens is time-consuming and costly work, we believe that use of cone-beam CT for hard tissue specimens can be useful in forensic practice.


Assuntos
Abscesso/diagnóstico por imagem , Patologia Legal/métodos , Mastoidite/diagnóstico por imagem , Meningite/diagnóstico por imagem , Lesões dos Tecidos Moles/diagnóstico por imagem , Abscesso/etiologia , Adulto , Abscesso Encefálico/diagnóstico por imagem , Abscesso Encefálico/etiologia , Tomografia Computadorizada de Feixe Cônico/instrumentação , Tomografia Computadorizada de Feixe Cônico/métodos , Traumatismos Craniocerebrais/diagnóstico por imagem , Traumatismos Craniocerebrais/etiologia , Patologia Legal/instrumentação , Humanos , Masculino , Processo Mastoide/diagnóstico por imagem , Processo Mastoide/patologia , Mastoidite/complicações , Meningite/complicações , Lesões do Pescoço/diagnóstico por imagem , Lesões do Pescoço/etiologia , Lesões dos Tecidos Moles/etiologia
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