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1.
Clin Dermatol ; 27(2): 195-201, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19168000

RESUMO

Less than 20 of the hundreds of carotenoids found in nature are found in the human body. These carotenoids are present in the body from the foods or dietary supplements that humans consume. The body does not synthesize them. Among the carotenoids present in the body, only lutein and its coexistent isomer, zeaxanthin, are found in that portion of the eye where light is focused by the lens, namely, the macula lutea. Numerous studies have shown that lutein and zeaxanthin may provide significant protection against the potential damage caused by light striking this portion of the retina. In the eye, lutein and zeaxanthin have been shown to filter high-energy wavelengths of visible light and act as antioxidants to protect against the formation of reactive oxygen species and subsequent free radicals. Human studies have demonstrated that lutein and zeaxanthin are present in the skin, and animal studies have provided evidence of significant efficacy against light-induced skin damage, especially the ultraviolet wavelengths. Little was known about the protective effects of these carotenoids in human skin until recently. This article reviews the scientific literature pertaining to the effects that lutein and zeaxanthin exhibit in the human eye and skin.


Assuntos
Luteína/fisiologia , Fenômenos Fisiológicos Oculares , Fenômenos Fisiológicos da Pele , Xantofilas/fisiologia , Humanos , Luz Solar/efeitos adversos , Zeaxantinas
2.
Biochem J ; 413(1): 193-200, 2008 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-18348712

RESUMO

CD148 is a transmembrane tyrosine phosphatase that has been implicated in the regulation of cell growth and transformation. However, the signalling mechanisms of CD148 are incompletely understood. To identify the specific intracellular molecules involved in CD148 signalling, we carried out a modified yeast two-hybrid screening assay. Using the substrate-trapping mutant form of CD148 (CD148 D/A) as bait, we recovered the p85 regulatory subunit of PI3K (phosphoinositide 3-kinase). CD148 D/A, but not catalytically active CD148, interacted with p85 in a phosphorylation-dependent manner in vitro and in intact cells. Growth factor receptor and PI3K activity were also trapped by CD148 D/A via p85 from pervanadate-treated cell lysates. CD148 prominently and specifically dephosphorylated p85 in vitro. Co-expression of CD148 reduced p85 phosphorylation induced by active Src, and attenuated the increases in PI3K activity, yet CD148 did not alter the basal PI3K activity. Finally, CD148 knock-down by siRNA (short interfering RNA) increased PI3K activity on serum stimulation. Taken together, these results demonstrate that CD148 may interact with and dephosphorylate p85 when it is phosphorylated and modulate the magnitude of PI3K activity.


Assuntos
Fosfatidilinositol 3-Quinases/metabolismo , Animais , Células CHO , Linhagem Celular , Cricetinae , Cricetulus , Humanos , Mutação , Fosfatidilinositol 3-Quinases/química , Ligação Proteica , Subunidades Proteicas , Proteínas Tirosina Fosfatases Classe 3 Semelhantes a Receptores/metabolismo , Receptores do Fator de Crescimento Derivado de Plaquetas/metabolismo , Técnicas do Sistema de Duplo-Híbrido
3.
Prostate ; 66(11): 1177-93, 2006 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-16652386

RESUMO

BACKGROUND: Mechanisms regulating the transition from hormone responsive to hormone refractory prostate cancer (PCa) have remained unclear. METHODS: We analyzed androgen and anti-androgen treatment on endogenous AR activity in primary human prostate epithelial (HPE) cells cultured directly from patient radical prostatectomy specimens utilizing a transiently infected gene reporter (TIGR) assay. RESULTS: Flutamide treatment exhibited agonist activities in HPE cells derived from tumor and non-tumor specimens which contained wild-type AR. After proteomic comparison of these cells to those where flutamide functioned normally as an antagonist, we identified DJ-1, a positive regulator of AR. DJ-1 expression increased in HPE and LNCaP cells during flutamide treatment as a result of DJ-1 protein stabilization. CONCLUSION: Stabilization of AR and its co-regulators in the absence of androgen may partially account for anti-androgen withdrawal syndrome and potentially contribute to the development of hormone refractory PCa.


Assuntos
Antagonistas de Androgênios/farmacologia , Androgênios/farmacologia , Células Epiteliais/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intracelular/efeitos dos fármacos , Proteínas Oncogênicas/efeitos dos fármacos , Próstata/efeitos dos fármacos , Receptores Androgênicos/efeitos dos fármacos , Linhagem Celular Tumoral , Análise Mutacional de DNA , Estabilidade de Medicamentos , Eletroforese em Gel Bidimensional , Células Epiteliais/química , Células Epiteliais/ultraestrutura , Flutamida/farmacologia , Expressão Gênica/efeitos dos fármacos , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/análise , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , Microscopia Eletrônica , Proteínas Oncogênicas/análise , Proteínas Oncogênicas/genética , Próstata/química , Próstata/ultraestrutura , Neoplasias da Próstata/química , Neoplasias da Próstata/genética , Proteína Desglicase DJ-1 , Receptores Androgênicos/genética , Receptores Androgênicos/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/efeitos dos fármacos , Transcrição Gênica/efeitos dos fármacos , Transfecção , Células Tumorais Cultivadas
4.
Development ; 132(15): 3431-43, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15987773

RESUMO

We have previously shown that a forkhead transcription factor Foxa1 interacts with androgen signaling and controls prostate differentiated response. Here, we show the mouse Foxa1 expression marks the entire embryonic urogenital sinus epithelium (UGE), contrasting with Shh and Foxa2, which are restricted to the basally located cells during prostate budding. The Foxa1-deficient mouse prostate shows a severely altered ductal pattern that resembles primitive epithelial cords surrounded by thick stromal layers. Characterization of these mutant cells indicates a population of basal-like cells similar to those found in the embryonic UGE, whereas no differentiated or mature luminal epithelial cells are found in Foxa1-deficient epithelium. These phenotypic changes are accompanied with molecular aberrations, including focal epithelial activation of Shh and elevated Foxa2 and Notch1 in the null epithelium. Perturbed epithelial-stromal interactions induced by Foxa1-deficient epithelium is evident, as demonstrated by the expansion of surrounding smooth muscle and elevated levels of stromal factors (Bmp4, Fgf7, Fgf10 and Gli). The prostatic homeobox protein Nkx3.1, a known proliferation inhibitor, was downregulated in Foxa1-deficient epithelial cells, while several prostate-specific androgen-regulated markers, including a novel Foxa1 target, are absent in the null prostate. These data indicate that Foxa1 plays a pivotal role in controlling prostate morphogenesis and cell differentiation.


Assuntos
Proteínas de Ligação a DNA/fisiologia , Células Epiteliais/fisiologia , Proteínas Nucleares/fisiologia , Próstata/embriologia , Fatores de Transcrição/fisiologia , Animais , Diferenciação Celular/fisiologia , Proteínas de Ligação a DNA/deficiência , Proteínas de Ligação a DNA/genética , Células Epiteliais/citologia , Regulação da Expressão Gênica no Desenvolvimento , Genes Reporter , Fator 3-alfa Nuclear de Hepatócito , Hibridização In Situ , Masculino , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Morfogênese , Proteínas Nucleares/deficiência , Proteínas Nucleares/genética , Próstata/citologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Fatores de Transcrição/deficiência , Fatores de Transcrição/genética
5.
Prostate ; 63(4): 369-84, 2005 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-15937962

RESUMO

BACKGROUND: We have sought to develop a new in vivo model of prostate carcinogenesis using human prostatic epithelial cell cultures. Human prostate cancers frequently display DNA amplification in the 8q24 amplicon, which leads to an increase in the copy number of the c-MYC gene, a finding that suggests a role for c-MYC in human prostate carcinogenesis. In addition overexpression of c-MYC in transgenic mouse models results in prostatic carcinogenesis. METHODS: We took advantage of the ability of retroviruses to integrate foreign DNA into human prostatic epithelium (huPrE) to generate cell lines that overexpress the c-MYC protooncogene. These cells were recombined with inductive rat urogenital sinus mesenchyme and grafted beneath the renal capsule of immunocompromised rodent hosts. RESULTS: The resultant tissue displayed a phenotype consistent with a poorly differentiated human prostatic adenocarcinoma. The tumors were rapidly growing with a high proliferative index. The neoplastic cells in the tumor expressed both androgen receptors (AR) and prostate-specific antigen (PSA), both characteristic markers of human prostate cancers. Microarray analysis of human prostatic epithelial cells overexpression c-MYC identified a large number of differentially expressed genes some of which have been suggested to characterize a subset of human cancers that have myc overexpression. Specific examples were confirmed by Western blot analysis and include upregulation of c-Myb and decreased expression of PTEN. Control grafts using either uninfected huPrE or using huPrE cells infected using an empty vector expressing a green fluorescent protein tag gave rise to well differentiated benign prostatic glandular ducts. CONCLUSIONS: By using a retroviral infection strategy followed by tissue recombination we have created a model of human prostate cancer that demonstrates that the c-MYC gene is sufficient to induce carcinogenesis.


Assuntos
Adenocarcinoma/genética , Próstata/citologia , Próstata/fisiologia , Neoplasias da Próstata/genética , Proteínas Proto-Oncogênicas c-myc/genética , Adenocarcinoma/patologia , Adenocarcinoma/fisiopatologia , Animais , Biomarcadores Tumorais , Células Cultivadas , Modelos Animais de Doenças , Epitélio/fisiologia , Regulação Neoplásica da Expressão Gênica , Técnicas de Transferência de Genes , Proteínas de Fluorescência Verde/genética , Humanos , Masculino , Camundongos , Camundongos SCID , Análise de Sequência com Séries de Oligonucleotídeos , Fenótipo , Neoplasias da Próstata/patologia , Neoplasias da Próstata/fisiopatologia , Retroviridae/genética
6.
J Endourol ; 19(4): 502-7, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15910266

RESUMO

BACKGROUND AND PURPOSE: Laparoscopic intravesical and standard Lich-Gregoir repair have been reported but are technically challenging. Herein, we present our experience with a simplified laparoscopic reimplantation of the ureter to correct vesicoureteral reflux (VUR). MATERIALS AND METHODS: Bilateral VUR was created cystoscopically in six minipigs, as confirmed by a static cystogram 6 weeks later. The laparoscopic extravesical correction of VUR was performed utilizing a full-thickness cystotomy. The ureter was transposed inside the bladder, and a full-thickness bladder closure was performed. No attempt was made to cover the ureter with urothelium. No stents or catheters were utilized postoperatively. Three months after reimplantation, the animals were evaluated with serology, a static cystogram, an intravenous urogram (IVU), and gross pathologic and histopathologic examination. RESULTS: The postoperative cystograms confirmed no reflux in all the reimplanted ureters and residual grade 1 to 3 reflux in the non-reimplanted ureters. All pigs voided normally and were completely continent. Cystoscopic evaluation revealed complete epithelialization over the reimplanted ureter. One surgical complication occurred: the ureter was incorporated into the bladder closure and became obstructed. The IVU in all other pigs demonstrated patent ureters with prompt function. CONCLUSIONS: Laparoscopic reimplantation of the ureter utilizing this modified Lich-Gregoir approach corrected reflux in all animals. The full-thickness bladder incision and intravesical transposition of the ureter greatly simplifies the laparoscopic procedure. This laboratory experience encourages further clinical evaluation in the pediatric population with VUR.


Assuntos
Laparoscopia/métodos , Reimplante/métodos , Ureter/cirurgia , Refluxo Vesicoureteral/cirurgia , Animais , Cistoscopia , Epitélio/patologia , Feminino , Modelos Animais , Radiografia , Técnicas de Sutura , Suínos , Bexiga Urinária/diagnóstico por imagem , Bexiga Urinária/cirurgia
7.
Invest Ophthalmol Vis Sci ; 46(3): 849-56, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15728540

RESUMO

PURPOSE: There are two human 15-lipoxygenases (LOX), 15-LOX-1 and -2, which convert arachidonic acid to 15S-hydroxyeicosatetraenoic acid (15S-HETE). The presence of both 15-LOXs in the human cornea prompted this study to delineate their roles in the human corneal epithelium. METHODS: Human corneal epithelia from donor corneas and a human corneal epithelial (HCE) cell line were used in [1-(14)C]arachidonic acid incubations, Western blot analysis, and quantitative real-time RT-PCR. Cell cultures of HCE were treated with 15S-HETE to measure its effect on cell growth. HCE cells were transfected with plasmids to express green fluorescent (GFP) fusion proteins of 15-LOX-1 and -2, and in vivo laser confocal microscopy was performed to determine the subcellular localization of the 15-LOX fusion proteins. RESULTS: [1-(14)C]Arachidonic acid incubations yielded 15S-HETE as the only LOX product. Treatment with 15S-HETE (5-10 microM) reduced growth rate and induced apoptosis in cultured HCE cells in a dose-dependent manner. 15-LOX-2 but not 15-LOX-1 was detected by Western blot analysis, although we were able to detect similar levels of both 15-LOX mRNAs by real-time quantitative RT-PCR. 15-LOX-1 and -2 proteins showed different subcellular expression patterns. 15-LOX-2 GFP was expressed in the cytoplasm and nucleus (actively taken up into the nucleus). 15-LOX-1 GFP fusion protein expression was restricted to the cytoplasm. CONCLUSIONS: These findings indicate that 15-LOX-2 is the predominant 15-LOX protein in human cornea, and its product, 15S-HETE, plays a role in cellular proliferation. Because the two 15-LOXs have different subcellular compartmentalization, the authors hypothesize that their products are also compartmentalized and therefore exert different molecular effects in the human corneal epithelium.


Assuntos
Araquidonato 15-Lipoxigenase/análise , Córnea/enzimologia , Araquidonato 15-Lipoxigenase/genética , Ácidos Araquidônicos/farmacologia , Western Blotting , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Epitélio Corneano/enzimologia , Humanos , Ácidos Hidroxieicosatetraenoicos/metabolismo , Ácidos Hidroxieicosatetraenoicos/farmacologia , Microscopia Confocal , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Frações Subcelulares
8.
J Biol Chem ; 280(10): 9610-7, 2005 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-15632119

RESUMO

Organic anion-transporting polypeptide 1A2 (OATP1A2) is a drug uptake transporter known for broad substrate specificity, including many drugs in clinical use. Therefore, genetic variation in SLCO1A2 may have important implications to the disposition and tissue penetration of substrate drugs. In the present study, we demonstrate OATP1A2 protein expression in human brain capillary and renal distal nephron using immunohistochemistry. We also determined the extent of single nucleotide polymorphisms in SLCO1A2 upon analyses of ethnically defined genomic DNA samples (n = 95 each for African-, Chinese-, European-, and Hispanic-Americans). We identified six nonsynonymous polymorphisms within the coding region of SLCO1A2 (T38C (I13T), A516C (E172D), G559A (A187T), A382T (N128Y), A404T (N135I), and C2003G (T668S)), the allelic frequencies of which appeared to be ethnicity-dependent. In vitro functional assessment revealed that the A516C and A404T variants had markedly reduced capacity for mediating the cellular uptake of OATP1A2 substrates, estrone 3-sulfate and two delta-opioid receptor agonists, deltorphin II, and [D-penicillamine(2,5)]-enkephalin. On the other hand, the G559A and C2003G variants appeared to have substrate-dependent changes in transport activity. Cell surface biotinylation and immunofluorescence confocal microscopy suggested that altered plasma membrane expression of the transporter may contribute to reduced transport activity associated with the A516C, A404T, and C2003G variants. The A404T (N135I) variant also showed a shift in the apparent molecular size, indicative of alterations in glycosylation status. Taken together, these data suggest that SLCO1A2 polymorphisms may be an important yet unrecognized contributor to inter-individual variability in drug disposition and central nervous system entry of substrate drugs.


Assuntos
Estrona/análogos & derivados , Transportador 1 de Ânion Orgânico Específico do Fígado/genética , Polimorfismo Genético , Sequência de Aminoácidos , Substituição de Aminoácidos , Encéfalo/fisiologia , D-Penicilina (2,5)-Encefalina/farmacologia , Estrona/farmacologia , Humanos , Rim/fisiologia , Cinética , Fígado/fisiologia , Transportador 1 de Ânion Orgânico Específico do Fígado/química , Modelos Moleculares , Dados de Sequência Molecular , Oligopeptídeos/farmacologia , Especificidade de Órgãos , Polimorfismo de Nucleotídeo Único , Conformação Proteica , Estrutura Secundária de Proteína
9.
Chem Res Toxicol ; 17(12): 1706-15, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15606148

RESUMO

Human small ubiquitin-like modifier (sumo) proteins include sumo-1 and the less studied, nearly identical sumo-2 and sumo-3 proteins. Whereas the structurally related ubiquitin molecule targets proteins for degradation, sumo provides a distinct, yet poorly understood regulatory signal. Protein sumoylation is sensitive to diverse cellular stresses, yet the targets of sumoylation in stress are unknown. We studied protein sumoylation in HEK293 cells exposed to hydrogen peroxide, alkylating agents, and the lipid oxidation-derived electrophile 4-hydroxynonenal, which is an ubiquitous product of lipid oxidation associated with oxidative stress. Confocal immunofluorescence microscopy indicated that in unstressed cells sumo-1 targeted nuclear proteins, whereas sumo-2/3 targeted proteins in both nuclei and cytoplasm. Western blot analyses revealed changes in sumo-1 and sumo-2/3 targeting patterns with stress. We used immunoaffinity chromatography to harvest sumo-associated proteins from HA-sumo-1- and HA-sumo-3-expressing HEK293 cells both before and after treatment with 4-hydroxynonenal. Multidimensional liquid chromatography-tandem mass spectrometry analyses identified 54 HA-sumo-1-associated proteins and 38 HA-sumo-3-associated proteins. Major protein targets included RNA binding and processing proteins, transcription factors, metabolic enzymes, and cytoskeletal regulators. Treatment with 4-hydroxynonenal caused a near-complete redistribution of sumo-1 and sumo-3 to different protein targets, which included chaperones, antioxidant, and DNA damage signaling proteins. A 10-15% overlap of sumo-1 and sumo-3 targets before and after stress suggests that sumo proteins target distinct protein groups. The results suggest that reactive electrophiles not only directly modify proteins but also lead to indirect changes in endogenous protein modifications that regulate protein functions.


Assuntos
Estresse Oxidativo , Proteínas/metabolismo , Proteína SUMO-1/fisiologia , Proteínas Modificadoras Pequenas Relacionadas à Ubiquitina/fisiologia , Aldeídos/toxicidade , Alquilantes/toxicidade , Sequência de Aminoácidos , Linhagem Celular , Vetores Genéticos , Humanos , Peróxido de Hidrogênio/toxicidade , Dados de Sequência Molecular , Plasmídeos , Proteínas/química , Proteína SUMO-1/genética , Transdução de Sinais , Proteínas Modificadoras Pequenas Relacionadas à Ubiquitina/genética
10.
Cancer Cell ; 6(2): 185-95, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15324701

RESUMO

The majority of cancer-related deaths are associated with metastasis; however, little is known about the mechanisms of this process. Hepsin is a cell surface serine protease that is markedly upregulated in human prostate cancer; however, the functional significance of this upregulation is unknown. We report here that hepsin overexpression in prostate epithelium in vivo causes disorganization of the basement membrane. Overexpression of hepsin in a mouse model of nonmetastasizing prostate cancer has no impact on cell proliferation, but causes disorganization of the basement membrane and promotes primary prostate cancer progression and metastasis to liver, lung, and bone. We provide in vivo evidence that upregulation of a cell surface serine protease in a primary tumor promotes cancer progression and metastasis.


Assuntos
Metástase Neoplásica , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Serina Endopeptidases/metabolismo , Animais , Apoptose , Membrana Basal/metabolismo , Membrana Basal/patologia , Membrana Basal/ultraestrutura , Diferenciação Celular , Divisão Celular , Modelos Animais de Doenças , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Transgênicos , Próstata/anatomia & histologia , Próstata/metabolismo , Próstata/patologia , Serina Endopeptidases/genética
11.
Hum Pathol ; 35(7): 840-9, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15257547

RESUMO

15-Lipoxygenase-2 (15-LOX-2) is an arachidonic acid-metabolizing enzyme expressed in prostate, lung, skin, esophagus, and cornea. In the benign prostate, it is expressed in differentiated secretory epithelial cells, where its enzymatic product 15-HETE may regulate transcription by activating the nuclear receptor peroxisome proliferator-activated receptor gamma (PPARgamma). 15-LOX-2 and 15-HETE formation are reduced in prostate carcinoma. The distribution of 15-LOX-2 in the normal lung and its expression in lung carcinomas has not been reported and was investigated in the current study by using immunohistochemistry and tissue microarrays (TMAs). In benign lung, 15-LOX-2 immunostaining was noted exclusively in type II pneumocytes, which are known to express PPARgamma. Of 160 lung carcinomas, 15-LOX-2 was expressed in non-small cell carcinomas (NSCLC), including 33 of 69 (48%) adenocarcinomas, with 10 of 16 (63%) bronchioloalveolar carcinomas immunopositive. Fourteen of 55 (25%) squamous cell carcinomas and 2 of 14 (14%) large cell carcinomas showed weak immunostaining. All 19 neuroendocrine tumors were negative. Better differentiated NSCLCs showed greater 15-LOX-2 expression, with a significant inverse correlation between 15-LOX-2 immunostaining and tumor grade (P < 0.03). A significant inverse correlation was also noted between 15-LOX-2 immunostaining and tumor cell proliferation (Ki-67 immunostaining; P < 0.0001). These findings suggest a possible role of 15-LOX-2 in regulating secretory differentiation and proliferation in benign lung and NSCLCs, particularly adenocarcinomas.


Assuntos
Araquidonato 15-Lipoxigenase/metabolismo , Carcinoma/enzimologia , Neoplasias Pulmonares/enzimologia , Pulmão/enzimologia , Sarcoma/enzimologia , Biomarcadores Tumorais/análise , Carcinoma/mortalidade , Carcinoma/patologia , Divisão Celular , Transformação Celular Neoplásica , Humanos , Imuno-Histoquímica , Pulmão/anatomia & histologia , Pulmão/patologia , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Estadiamento de Neoplasias , Sarcoma/mortalidade , Sarcoma/patologia , Taxa de Sobrevida
13.
Cancer Res ; 64(6): 2270-305, 2004 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-15026373

RESUMO

The Pathological Classification of Prostate Lesions in Genetically Engineered Mice (GEM) is the result of a directive from the National Cancer Institute Mouse Models of Human Cancer Consortium Prostate Steering Committee to provide a hierarchical taxonomy of disorders of the mouse prostate to facilitate classification of existing and newly created mouse models and the translation to human prostate pathology. The proposed Bar Harbor Classification system is the culmination of three meetings and workshops attended by various members of the Prostate Pathology Committee of the Mouse Models of Human Cancer Consortium. A 2-day Pathology Workshop was held at The Jackson Laboratory in Bar Harbor, Maine, in October 2001, in which study sets of 93 slides from 22 GEM models were provided to individual panel members. The comparison of mouse and human prostate anatomy and disease demonstrates significant differences and considerable similarities that bear on the interpretation of the origin and natural history of their diseases. The recommended classification of mouse prostate pathology is hierarchical, and includes developmental, inflammatory, benign proliferative, and neoplastic disorders. Among the neoplastic disorders, preinvasive, microinvasive, and poorly differentiated neoplasms received the most attention. Specific criteria were recommended and will be discussed. Transitions between neoplastic states were of particular concern. Preinvasive neoplasias of the mouse prostate were recognized as focal, atypical, and progressive lesions. These lesions were designated as mouse prostatic intraepithelial neoplasia (mPIN). Some atypical lesions were identified in mouse models without evidence of progression to malignancy. The panel recommended that mPIN lesions not be given histological grades, but that mPIN be further classified as to the absence or presence of documented associated progression to invasive carcinoma. Criteria for recognizing microinvasion, for classification of invasive gland-forming adenocarcinomas, and for characterizing poorly differentiated tumors, including neuroendocrine carcinomas, were developed and are discussed. The uniform application of defined terminology is essential for correlating results between different laboratories and models. It is recommended that investigators use the Bar Harbor Classification system when characterizing new GEM models or when conducting experimental interventions that may alter the phenotype or natural history of lesion progression in existing models.


Assuntos
Animais Geneticamente Modificados , Modelos Animais de Doenças , Neoplasias da Próstata/patologia , Animais , Engenharia Genética , Humanos , Masculino , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Lesões Pré-Cancerosas , Hiperplasia Prostática/classificação , Hiperplasia Prostática/genética , Hiperplasia Prostática/patologia , Neoplasias da Próstata/classificação , Neoplasias da Próstata/genética , Terminologia como Assunto
14.
Breast Cancer Res ; 6(2): R130-9, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-14979923

RESUMO

BACKGROUND: The transforming growth factor-beta (TGF-beta) signaling pathway functions to prevent tumorigenesis, and loss of sensitivity to TGF-beta-mediated cell cycle arrest is nearly ubiquitous among human cancers. Our previous studies demonstrated that rapamycin potentiates TGF-beta-induced cell cycle arrest in nontransformed epithelial cells and partially restores TGF-beta-induced growth arrest of some human cancer cell lines. Growth arrest correlated with increased binding of p21 and p27 to cyclin-dependent kinase-2 (Cdk2), and inhibition of Cdk2 kinase activity. However, it was unclear how TGF-beta caused increased binding of p21 and p27 to Cdk2. METHODS: Cell fractionation and immunofluorescence microscopy experiments were performed to examine the effect of TGF-beta on the intracellular localization of Cdk2, p21, and p27. Kinase assays were performed on cytoplasmic and nuclear extracts to determine how TGF-beta altered Cdk2 activity in both subcellular compartments. RESULTS: In breast epithelial cells treatment with TGF-beta induced a decrease in nuclear Cdk2 concentrations and relocalization of Cdk2 to the cytoplasm. Cdk2 relocalization to the cytoplasm correlated with dephosphorylation of nuclear retinoblastoma tumor suppressor protein and decreased nuclear Cdk2 activity. In these epithelial cell lines, p21 and p27 were localized primarily in the cytoplasm. Decreases in nuclear Cdk2 concentrations correlated with increased binding of Cdk2 to cytoplasmic p21 and p27. CONCLUSION: Cooperative growth arrest induced by treatment with TGF-beta + rapamycin causes inhibition of nuclear Cdk2 activity through multiple mechanisms, including Cdk2 relocalization to the cytoplasm, increased p27 and p21 binding to Cdk2, and increased phosphorylation of nuclear Cdk2 on its inhibitory site, Tyr15.


Assuntos
Transporte Ativo do Núcleo Celular/fisiologia , Quinases relacionadas a CDC2 e CDC28/metabolismo , Citoplasma/enzimologia , Proteína do Retinoblastoma/metabolismo , Fator de Crescimento Transformador beta/fisiologia , Proteínas Supressoras de Tumor/metabolismo , Animais , Quinases relacionadas a CDC2 e CDC28/antagonistas & inibidores , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Núcleo Celular/enzimologia , Quinase 2 Dependente de Ciclina , Inibidor de Quinase Dependente de Ciclina p27 , Células Epiteliais/química , Células Epiteliais/metabolismo , Humanos , Queratinócitos/química , Queratinócitos/citologia , Queratinócitos/metabolismo , Glândulas Mamárias Animais/citologia , Glândulas Mamárias Humanas/citologia , Camundongos , Fosforilação , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Sirolimo/farmacologia
15.
J Biol Chem ; 279(8): 7213-22, 2004 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-14660639

RESUMO

The key transporter responsible for hepatic uptake of bile acids from portal circulation is Na+-taurocholate cotransporting polypeptide (NTCP, SLC10A1). This transporter is thought to be critical for the maintenance of enterohepatic recirculation of bile acids and hepatocyte function. Therefore, functionally relevant polymorphisms in this transporter would be predicted to have an important impact on bile acid homeostasis/liver function. However, little is known regarding genetic heterogeneity in NTCP. In this study, we demonstrate the presence of multiple single nucleotide polymorphisms in NTCP in populations of European, African, Chinese, and Hispanic Americans. Specifically four nonsynonymous single nucleotide polymorphisms associated with a significant loss of transport function were identified. Cell surface biotinylation experiments indicated that the altered transport activity of T668C (Ile223-->Thr), a variant seen only in African Americans, was due at least in part to decreased plasma membrane expression. Similar expression patterns were observed when the variant alleles were expressed in HepG2 cells, and plasma membrane expression was assessed using immunofluorescence confocal microscopy. Interestingly the C800T (Ser267-->Phe) variant, seen only in Chinese Americans, exhibited a near complete loss of function for bile acid uptake yet fully normal transport function for the non-bile acid substrate estrone sulfate, suggesting this position may be part of a region in the transporter critical and specific for bile acid substrate recognition. Accordingly, our study indicates functionally important polymorphisms in NTCP exist and that the likelihood of being carriers of such polymorphisms is dependent on ethnicity.


Assuntos
Ácidos e Sais Biliares/metabolismo , Proteínas de Transporte/genética , Transportadores de Ânions Orgânicos Dependentes de Sódio , Polimorfismo Genético , Simportadores , Ácido Taurocólico/química , Alelos , Sequência de Aminoácidos , Povo Asiático , Ácidos e Sais Biliares/química , Transporte Biológico , Biotinilação , População Negra , Proteínas de Transporte/química , Linhagem Celular , Membrana Celular/metabolismo , Relação Dose-Resposta a Droga , Eletroforese em Gel de Poliacrilamida , Frequência do Gene , Genótipo , Glicosilação , Células HeLa , Hepatócitos/metabolismo , Hispânico ou Latino , Humanos , Microscopia Confocal , Dados de Sequência Molecular , Plasmídeos/metabolismo , Polimorfismo de Nucleotídeo Único , Ligação Proteica , Estrutura Terciária de Proteína , Homologia de Sequência de Aminoácidos , Especificidade por Substrato , Vaccinia virus/genética , População Branca
16.
Proc Natl Acad Sci U S A ; 100(25): 14914-9, 2003 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-14645706

RESUMO

Mammalian fertility absolutely depends on synchronized development of the blastocyst to the stage when it is competent to implant, and the uterus to the stage when it is receptive to implantation. However, the molecular basis for the reciprocal interaction between the embryo and the uterus remains largely unexplored. One potentially important mechanism involves signaling between an evolutionarily conserved G protein-coupled protein cannabinoid receptor, CB1, that is expressed at high levels on the surface of the trophectoderm and anandamide (N-arachi-donoylethanolamine), an endocannabinoid ligand found to be produced at higher levels by the uterus before implantation and then down-regulated at the time of implantation. Using genetic, pharmacological, and physiological approaches, we show here that anandamide within a very narrow range regulates blastocyst function and implantation by differentially modulating mitogen-activated protein kinase signaling and Ca2+ channel activity via CB1 receptors. Anandamide at a low concentration (7 nM) induces extracellular regulated kinase phosphorylation and nuclear translocation in trophectoderm cells without influencing Ca2+ channels, and renders the blastocyst competent for implantation in the receptive uterus. In contrast, anandamide at a higher concentration (28 nM) inhibits Ca2+ channel activity and blastocyst competency for implantation without influencing mitogen-activated protein kinase signaling. Besides uncovering a potentially important regulatory mechanism for synchronizing blastocyst and uterine competency to implantation, this observation has high clinical relevance, because elevated levels of anandamide induce spontaneous pregnancy loss in women.


Assuntos
Ácidos Araquidônicos/farmacologia , Blastocisto/metabolismo , Ácido Egtázico/análogos & derivados , Implantação do Embrião , Receptores de Canabinoides/metabolismo , Transdução de Sinais , Animais , Cálcio/metabolismo , Moduladores de Receptores de Canabinoides/farmacologia , Diferenciação Celular , Quelantes/farmacologia , Regulação para Baixo , Ácido Egtázico/farmacologia , Endocanabinoides , Ativação Enzimática , Fertilidade , Proteínas de Ligação ao GTP/metabolismo , Genótipo , Glutationa Transferase/metabolismo , Ligantes , Sistema de Sinalização das MAP Quinases , Camundongos , Camundongos Mutantes , Microscopia de Fluorescência , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Alcamidas Poli-Insaturadas , Receptor CB1 de Canabinoide/metabolismo , Fatores de Tempo , Regulação para Cima
17.
EMBO J ; 22(24): 6471-82, 2003 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-14657020

RESUMO

We describe a novel signaling mechanism mediated by the G-protein-coupled receptor (GPCR) angiotensin II (Ang II) type 2 receptor (AT(2)). Yeast two-hybrid studies and affinity column binding assay show that the isolated AT(2) C-terminus binds to the transcription factor promyelocytic zinc finger protein (PLZF). Cellular studies employing confocal microscopy show that Ang II stimulation induces cytosolic PLZF to co-localize with AT(2) at the plasma membrane, then drives AT(2) and PLZF to internalize. PLZF slowly emerges in the nucleus whereas AT(2) accumulates in the perinuclear region. Nuclear PLZF binds to a consensus sequence of the phosphatidylinositol-3 kinase p85 alpha subunit (p85 alpha PI3K) gene. AT(2) enhances expression of p85 alpha PI3K followed by enhanced p70(S6) kinase, essential to protein synthesis. An inactive mutant of PLZF abolishes this effect. PLZF is expressed robustly in the heart in contrast to many other tissues. This cardiac selective pathway involving AT(2), PLZF and p85 alpha PI3K may explain the absence of a cardiac hypertrophic response in AT(2) gene-deleted mice.


Assuntos
Cardiomegalia/genética , Cardiomegalia/fisiopatologia , Coração/fisiologia , Receptor Tipo 2 de Angiotensina/genética , Transdução de Sinais/fisiologia , Sequência de Aminoácidos , Animais , Células CHO , Cardiomegalia/prevenção & controle , Clonagem Molecular , Sequência Conservada , Cricetinae , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Humanos , Fatores de Transcrição Kruppel-Like , Camundongos , Camundongos Knockout , Dados de Sequência Molecular , Fosfatidilinositol 3-Quinases/metabolismo , Proteína com Dedos de Zinco da Leucemia Promielocítica , Transporte Proteico , Ratos , Receptor Tipo 2 de Angiotensina/deficiência , Receptor Tipo 2 de Angiotensina/metabolismo , Proteínas Quinases S6 Ribossômicas/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transfecção , Dedos de Zinco
18.
Circ Res ; 93(5): 448-55, 2003 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-12893739

RESUMO

Fatty acid oxidation (FAO) defects are inborn errors of metabolism clinically associated with cardiomyopathy and sudden infant death syndrome (SIDS). FAO disorders often present in infancy with myocardial dysfunction and arrhythmias after exposure to stresses such as fasting, exercise, or intercurrent viral illness. It is uncertain whether the heart, in the absence of stress, is normal. We generated very-long-chain acyl-coenzyme A dehydrogenase (VLCAD)-deficient mice by homologous recombination to define the onset and molecular mechanism of myocardial disease. We found that VLCAD-deficient hearts have microvesicular lipid accumulation, marked mitochondrial proliferation, and demonstrated facilitated induction of polymorphic ventricular tachycardia, without antecedent stress. The expression of acyl-CoA synthase (ACS1), adipophilin, activator protein 2, cytochrome c, and the peroxisome proliferator activated receptor gamma coactivator-1 were increased immediately after birth, preceding overt histological lipidosis, whereas ACS1 expression was markedly downregulated in the adult heart. We conclude that mice with VLCAD deficiency have altered expression of a variety of genes in the fatty acid metabolic pathway from birth, reflecting metabolic feedback circuits, with progression to ultrastructural and physiological correlates of the associated human disease in the absence of stress.


Assuntos
Ácidos Graxos Dessaturases/deficiência , Ácidos Graxos Dessaturases/genética , Função Ventricular , Acil-CoA Desidrogenase de Cadeia Longa , Animais , Animais Recém-Nascidos , Arritmias Cardíacas/fisiopatologia , Ecocardiografia , Ácidos Graxos Dessaturases/metabolismo , Feminino , Genótipo , Frequência Cardíaca/efeitos dos fármacos , Frequência Cardíaca/fisiologia , Ventrículos do Coração/enzimologia , Ventrículos do Coração/fisiopatologia , Isoproterenol/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos , Camundongos Transgênicos , Microscopia Eletrônica , Músculo Esquelético/metabolismo , Músculo Esquelético/ultraestrutura , Miocárdio/metabolismo , Miocárdio/patologia , Miocárdio/ultraestrutura , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fatores de Tempo , Fatores de Transcrição/genética
19.
J Endourol ; 17(5): 307-12, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12885356

RESUMO

BACKGROUND AND PURPOSE: Laparoscopic radical cystectomy with orthotopic ileal neobladder creation is a technically challenging and lengthy surgical procedure. We present our experience with a simplified technique for laparoscopic cystectomy and neobladder creation in the porcine model. MATERIALS AND METHODS: Ten female minipigs underwent a purely laparoscopic radical cystectomy with orthotopic ileal neobladder creation. Nine ureterointestinal anastomoses were performed using a simplified "dunk" technique, where the ureter was prolapsed 5 mm into the afferent limb and the periureteral tissue was secured to the bowel serosa with three superficial sutures. Six ureters were not stented, and three had indwelling stents inserted. In 11 ureters, the anastomosis was performed using a running mucosa-to-mucosa technique (three with stents, eight without stents). The Lapra-Ty suture clip (Ethicon Endosurgery, Cincinnati, OH) was used to secure the running sutures on the urethra, ureters, and neobladder. Animals were harvested at 3 to 8 weeks (mean 6.5 weeks) after surgery. Serology, static cystogram, intravenous urography, and gross and histopathologic evaluations were performed. RESULTS: Of six unstented dunked ureterointestinal anastomoses, two (33%) were widely patent, two were strictured but patent, and two were completely obstructed. In the three stented ureters implanted using the dunk technique, one (33%) was widely patent, one was strictured, and one was completely obstructed. All ureterointestinal anastomoses performed with a mucosa-to-mucosa running anastomosis, whether stented (three ureters) or not stented (eight ureters), were widely patent. Lapra-Ty clip migration into the neobladder pouch caused urethral obstruction resulting in delayed bladder perforation in two animals. CONCLUSIONS: Laparoscopic cystectomy and ileal neobladder creation is technically feasible. Attempts to simplify the ureterointestinal anastomosis require further evaluation and modification. Stent placement appears to be unnecessary in the laparoscopic ureterointestinal anastomosis. Laparoscopic creation of the ileal neobladder remains a technically challenging procedure.


Assuntos
Cistectomia/métodos , Íleo/cirurgia , Laparoscopia/métodos , Coletores de Urina , Anastomose Cirúrgica , Animais , Modelos Animais de Doenças , Feminino , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Recuperação de Função Fisiológica , Porco Miniatura , Resultado do Tratamento , Urodinâmica
20.
Neoplasia ; 5(3): 267-77, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12869309

RESUMO

In breast and colon cancers, transforming growth factor (TGF)-beta signaling initially has an antineoplastic effect, inhibiting tumor growth, but eventually exerts a proneoplastic effect, increasing motility and cancer spread. In prostate cancer, studies using human samples have correlated the loss of the TGF-beta type II receptor (T beta R II) with higher tumor grade. To determine the effect of an inhibited TGF-beta pathway on prostate cancer, we bred transgenic mice expressing the tumorigenic SV40 large T antigen in the prostate with transgenic mice expressing a dominant negative T beta R II mutant (DN II R) in the prostate. Transgene(s) and TGF-beta 1 expression were identified in the prostate and decreased protein levels of plasminogen activator inhibitor type I, as a marker for TGF-beta signaling, correlated with expression of the DN II R. Although the sizes of the neoplastic prostates were not enlarged, increased amounts of metastasis were observed in mice expressing both transgenes compared to age-matched control mice expressing only the large T antigen transgene. Our study demonstrates for the first time that a disruption of TGF-beta signaling in prostate cancer plays a causal role in promoting tumor metastasis.


Assuntos
Metástase Neoplásica , Neoplasias da Próstata/patologia , Fator de Crescimento Transformador beta/metabolismo , Animais , Humanos , Imuno-Histoquímica , Hibridização In Situ , Masculino , Camundongos , Camundongos Transgênicos , Mutação , Próstata/patologia , Proteínas Serina-Treonina Quinases , Receptor do Fator de Crescimento Transformador beta Tipo II , Receptores de Fatores de Crescimento Transformadores beta/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/fisiologia , Fator de Crescimento Transformador beta/genética , Transgenes
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