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1.
Ther Innov Regul Sci ; 53(3): 340-348, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-29976102

RESUMO

OBJECTIVES: This study of 23 US-based biopharmaceutical medical information (MI) websites was conducted to assess usability and identify best practices and areas of potential improvement. METHODS: In this systematic review, websites were evaluated from June 22-November 1, 2016, and awarded points based on content, functionality, and navigation (maximum score of 42). Low-, mid-, and high-range usability scores were ≤13, 14-27, ≥28, respectively. RESULTS: Mean scores were 7 of 17, 4 of 10, and only 5 of 15 criteria for content, functionality, and navigation. The mean usability score across all websites was 15 of 42 criteria. Larger companies generally had a higher mean usability score. A minor trend was also observed with regard to usability score and industry size (r2 = 0.3). Only 2 websites scored high, whereas 13 scored in the mid- and 8 in the lower range of usability. Overall, websites scored low when pertaining to presence of novel content type, search engine optimization, presence of social media, and MI services offered. Overall site architecture, presence of self-certification, and mobile compatibility scored fairly well across the industry. CONCLUSION: The majority of websites scored in the low to midrange, which suggests an industry-wide opportunity for improvement. In order to meet the evolving needs of health care professionals, MI websites need to be optimized for content, navigation, and functionality. Ensuring MI websites are discoverable through search engines and improving the level of MI services offered was also deemed to be important features to incorporate into a given MI website optimization strategy.


Assuntos
Benchmarking/métodos , Informática Médica/métodos , Indústria Farmacêutica , Guias como Assunto , Humanos , Ferramenta de Busca , Mídias Sociais
2.
Sci Rep ; 6: 32759, 2016 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-27609464

RESUMO

Bmps are morphogens involved in various gastric cellular functions. Studies in genetically-modified mice have shown that Bmp disruption in gastric epithelial and stromal cell compartments leads to the development of tumorigenesis. Our studies have demonstrated that abrogation of gastric epithelial Bmp signaling alone was not sufficient to recapitulate the neoplastic features associated with total gastric loss of Bmp signaling. Thus, epithelial Bmp signaling does not appear to be a key player in gastric tumorigenesis initiation. These observations suggest a greater role for stromal Bmp signaling in gastric polyposis initiation. In order to identify the specific roles played by mesenchymal Bmp signaling in gastric homeostasis, we generated a mouse model with abrogation of Bmp signaling exclusively in the gastro-intestinal mesenchyme (Bmpr1a(ΔMES)). We were able to expose an unsuspected role for Bmp loss of signaling in leading normal gastric mesenchyme to adapt into reactive mesenchyme. An increase in the population of activated-fibroblasts, suggesting mesenchymal transdifferentiation, was observed in mutant stomach. Bmpr1a(ΔMES) stomachs exhibited spontaneous benign polyps with presence of both intestinal metaplasia and spasmolytic-polypeptide-expressing metaplasia as early as 90 days postnatal. These results support the novel concept that loss of mesenchymal Bmp signaling cascade acts as a trigger in gastric polyposis initiation.


Assuntos
Pólipos Adenomatosos/genética , Receptores de Proteínas Morfogenéticas Ósseas Tipo I/genética , Proteínas Morfogenéticas Ósseas/metabolismo , Transformação Celular Neoplásica/genética , Neoplasias Gástricas/genética , Células Estromais/metabolismo , Pólipos Adenomatosos/metabolismo , Animais , Diferenciação Celular , Proliferação de Células , Transformação Celular Neoplásica/metabolismo , Regulação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Camundongos , Transdução de Sinais , Neoplasias Gástricas/metabolismo
3.
Int J Cancer ; 138(11): 2700-12, 2016 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-26773796

RESUMO

In the colon, myofibroblasts are primary contributors in the establishment of the microenvironment involved in tissue homeostasis. Alterations in myofibroblast functions lead to changes resulting in a toxic microenvironment nurturing tumorigenesis. Bone morphogenetic proteins (Bmps) are morphogens known to play key roles in adult gut homeostasis. Studies in genetically-modified mice have shown that Bmp disruption in all cell layers leads to the development of gut polyposis. In contrast, our studies showed that loss of Bmp exclusively in the gastrointestinal epithelium resulted in increased epithelial proliferation without polyposis initiation, thus suggesting a key role for mesenchymal Bmp signaling in polyposis initiation. In order to identify the role of mesenchymal Bmp signaling on the microenvironment and its impact on colonic mucosa, a mouse model was generated with suppression of Bmp signaling exclusively in myofibroblasts (Bmpr1aΔMES). Bmpr1aΔMES mice exhibited increased subepithelial proliferation with changes in cellular composition leading to the development of a primed stroma with modulation of extracellular matrix proteins, immune cells and cytokines as early as 90 days of age. This microenvironmental deregulation was associated with increased polyposis initiation at one year of age. These results are the first to demonstrate that mesenchymal Bmpr1a inactivation alone is sufficient to prompt an expansion of myofibroblasts leading to the development of a reactive mesenchyme that contributes to polyposis initiation in the colon. These findings support the novel concept that inhibition of Bmp signaling in mesenchymal cells surrounding the normal epithelium leads to important changes instructing a toxic microenvironment sufficient to induce colonic polyposis.


Assuntos
Receptores de Proteínas Morfogenéticas Ósseas Tipo I/genética , Neoplasias Colorretais/genética , Neoplasias Gastrointestinais/genética , Animais , Animais Geneticamente Modificados , Receptores de Proteínas Morfogenéticas Ósseas Tipo I/antagonistas & inibidores , Carcinogênese/genética , Diferenciação Celular/genética , Proliferação de Células/genética , Colo/metabolismo , Colo/patologia , Neoplasias Colorretais/patologia , Neoplasias Gastrointestinais/patologia , Humanos , Mesoderma/crescimento & desenvolvimento , Mesoderma/patologia , Camundongos , Mucosa/metabolismo , Mucosa/patologia , Células Estromais/metabolismo , Células Estromais/patologia , Microambiente Tumoral/genética
4.
Biochim Biophys Acta ; 1849(12): 1411-22, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26477491

RESUMO

Intestinal epithelial cells are exposed to luminal bacterial threat and require adequate defense mechanisms to ensure host protection and epithelium regeneration against possible deleterious damage. Differentiated intestinal epithelial cells produce antimicrobial and regenerative components that protect against such challenges. Few intestinal specific transcription factors have been identified to control the switching from repression to activation of this class of gene. Herein, we show that gene transcription of some regenerating islet-derived (REG) family members is dependent on the transcription factor GATA-4. Silencing of GATA-4 expression in cultured intestinal epithelial cells identified Reg3ß as a target gene using an unbiased approach of gene expression profiling. Co-transfection and RNA interference assays identified complex GATA-4-interactive transcriptional components required for the activation or repression of Reg3ß gene activity. Conditional deletion of Gata4 in the mouse intestinal epithelium supported its regulatory role for Reg1, Reg3α, Reg3ß and Reg3γ genes. Reg1 dramatic down-modulation of expression in Gata4 conditional null mice was associated with a significant decrease in intestinal epithelial cell migration. Altogether, these results identify a novel and complex role for GATA-4 in the regulation of REG family members gene expression.


Assuntos
Células Epiteliais/metabolismo , Fator de Transcrição GATA4/fisiologia , Regulação da Expressão Gênica/genética , Mucosa Intestinal/citologia , Família Multigênica , Transcrição Gênica , Animais , Antígenos de Neoplasias/metabolismo , Biomarcadores Tumorais/metabolismo , Fator de Transcrição CDX2 , Diferenciação Celular/genética , Linhagem Celular , Técnicas de Cocultura , Fator de Transcrição GATA4/classificação , Fator de Transcrição GATA4/deficiência , Fator de Transcrição GATA4/genética , Genes Reporter , Proteínas de Homeodomínio/metabolismo , Lectinas Tipo C/metabolismo , Litostatina/metabolismo , Camundongos , Camundongos Knockout , Mutagênese Sítio-Dirigida , Proteínas Associadas a Pancreatite , Estrutura Terciária de Proteína , Proteínas/metabolismo , Interferência de RNA , RNA Interferente Pequeno/genética , Ratos , Fatores de Transcrição/metabolismo , Fatores de Transcrição/fisiologia
5.
Int J Oncol ; 43(6): 2015-22, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24100580

RESUMO

The transcription factor E2F4 plays a critical role in cell cycle progression of normal and cancerous intestinal epithelial cells. Contrary to other E2Fs, the coding region of the E2F4 gene contains a longer spacer segment of a CAG trinucleotide repeat sequence encoding 13 consecutive serine residues, which is highly vulnerable to frameshift mutations in situations of genetic instability. Mutations in this region of the E2F4 gene have been observed in colorectal tumors with microsatellite instability. However, the effect of these changes on its function in colorectal cancer cells is currently unknown. We generated E2F4(CAG)12 and E2F4(CAG)14 mutants and compared their activity to the E2F4 wild-type, E2F4(CAG)13. Luciferase assays with the thymidine kinase-luc reporter gene revealed that the mutants were more transcriptionally active than wild-type E2F4. The mechanism of increased activity of E2F4 was primarily related to protein stability, due to a significantly enhanced half-life of E2F4 mutants comparatively to that of wild-type E2F4. However, the association with the pocket protein p130/RBL2 did not account for this increased protein stability. Sequencing analysis of the endogenous E2F4 gene in a series of colorectal cancer cell lines showed that the microsatellite-unstable cell line SW48 exhibited a serine deletion in this gene. Accordingly, E2F4 half-life was much more elevated in SW48 cells in comparison to Caco-2/15, a microsatellite-stable cell line. Notably, in soft-agar assays, both mutants more potently increased anchorage-independent growth in comparison to wild-type E2F4. In conclusion, our data demonstrate that cancer-associated E2F4 mutations enhance the capacity of colorectal cancer cells to grow without anchorage, thereby contributing to tumor progression.


Assuntos
Neoplasias Colorretais/genética , Fator de Transcrição E2F4/genética , Instabilidade de Microssatélites , Proteína p130 Retinoblastoma-Like/metabolismo , Sequência de Aminoácidos , Substituição de Aminoácidos/genética , Células CACO-2 , Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células , Células HCT116 , Células HEK293 , Células HT29 , Humanos , Mutação/genética , Proteína p130 Retinoblastoma-Like/genética , Análise de Sequência de DNA , Transcrição Gênica/genética , Repetições de Trinucleotídeos/genética
6.
Mol Cell Biol ; 33(11): 2275-84, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23530062

RESUMO

Polymorphisms of PTPN11 encoding SHP-2 are biomarkers for ulcerative colitis (UC) susceptibility. However, their functional relevance is unknown. We thus investigated the role of epithelial SHP-2 in the control of intestinal homeostasis. Mice with an intestinal epithelial cell-specific SHP-2 deletion (SHP-2(IEC-KO) mice) were generated. Control and SHP-2(IEC-KO) mice were monitored for clinical symptoms and sacrificed for histological staining and Western blot analyses. Cytokines and chemokines, as well as intestinal permeability, were quantified. SHP-2 mRNA expression was evaluated in control and UC patients. SHP-2(IEC-KO) mice showed growth retardation compared to control littermates and rapidly developed severe colitis. Colon architecture was markedly altered with infiltration of immune cells, crypt abscesses, neutrophil accumulation, and reduced goblet cell numbers. Decreased expression of claudins was associated with enhanced intestinal permeability in mutant SHP-2(IEC-KO) mice. Inflammatory transcription factors Stat3 and NF-κB were hyperactivated early in the mutant colonic epithelium. Levels of several epithelial chemokines and cytokines were markedly enhanced in SHP-2(IEC-KO) mice. Of note, antibiotic treatment remarkably impaired the development of colitis in SHP-2(IEC-KO) mice. Finally, SHP-2 mRNA levels were significantly reduced in intestinal biopsy specimens from UC patients. Our results establish intestinal epithelial SHP-2 as a critical determinant for prevention of gut inflammation.


Assuntos
Colite Ulcerativa/enzimologia , Colite/genética , Intestinos/fisiopatologia , Proteína Tirosina Fosfatase não Receptora Tipo 11/genética , Proteína Tirosina Fosfatase não Receptora Tipo 11/metabolismo , Animais , Antibacterianos/farmacologia , Colite/tratamento farmacológico , Colite/fisiopatologia , Colite Ulcerativa/genética , Células Epiteliais/enzimologia , Células Epiteliais/metabolismo , Feminino , Humanos , Mucosa Intestinal/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , NF-kappa B/genética , NF-kappa B/metabolismo , Permeabilidade , Gravidez , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo
7.
Am J Physiol Gastrointest Liver Physiol ; 301(4): G719-30, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21737780

RESUMO

The Ras/Raf/MEK/ERK cascade regulates intestinal epithelial cell proliferation. Indeed, while barely detectable in differentiated cells of the villi, ERK1/2-activated forms are detected in the nucleus of undifferentiated human intestinal crypt cells. In addition, we and others have reported that ERKs are selectively inactivated during enterocyte differentiation. However, whether inactivation of the ERK pathway is necessary for inhibition of both proliferation and induction of differentiation of intestinal epithelial cells is unknown. Human Caco-2/15 cells, undifferentiated crypt IEC-6 cells, and differentiating Cdx3-expressing IEC-6 cells were infected with retroviruses encoding either a hemagglutinin (HA)-tagged MEK1 wild type (wtMEK) or a constitutively active S218D/S222D MEK1 mutant (caMEK). Protein and gene expression was assessed by Western blotting, semiquantitative RT-PCR, and real-time PCR. Morphology was analyzed by transmission electron microscopy. We found that 1) IEC-6/Cdx3 cells formed multicellular layers after confluence and differentiated after 30 days in culture, as assessed by increased polarization, microvilli formation, expression of differentiation markers, and ERK1/2 inhibition; 2) while activated MEK prevented neither the inhibition of ERK1/2 activities nor the differentiation process in postconfluent Caco-2/15 cells, caMEK expression prevented ERK inhibition in postconfluent IEC-6/Cdx3 cells, thus leading to maintenance of elevated ERK1/2 activities; 3) caMEK-expressing IEC-6/Cdx3 cells exhibited altered multicellular structure organization, poorly defined tight junctions, reduced number of microvilli on the apical surface, and decreased expression of the hepatocyte nuclear factor 1α transcription factor and differentiation markers, namely apolipoprotein A-4, fatty acid-binding protein, calbindin-3, mucin 2, alkaline phosphatase, and sucrase-isomaltase; and 4) increased Cdx3 phosphorylation on serine-60 (S60) in IEC-6/Cdx3 cells expressing caMEK led to decreased Cdx2 transactivation potential. These results indicate that inactivation of the ERK pathway is required to ensure the full Cdx2/3 transcriptional activity necessary for intestinal epithelial cell terminal differentiation.


Assuntos
Diferenciação Celular/fisiologia , Mucosa Intestinal/citologia , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Animais , Fator de Transcrição CDX2 , Células CACO-2 , Células Cultivadas , Células Epiteliais/metabolismo , Proteínas de Homeodomínio/fisiologia , Humanos , MAP Quinase Quinase 1/metabolismo , Sistema de Sinalização das MAP Quinases , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Ratos , Transativadores/fisiologia
8.
Mol Cancer ; 9: 271, 2010 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-20942929

RESUMO

BACKGROUND: Among the most harmful of all genetic abnormalities that appear in colorectal cancer (CRC) development are mutations of KRAS and its downstream effector BRAF as they result in abnormal extracellular signal-related kinase (ERK) signaling. In a previous report, we had shown that expression of a constitutive active mutant of MEK1 (caMEK) in normal rat intestinal epithelial cells (IECs) induced morphological transformation associated with epithelial to mesenchymal transition, growth in soft agar, invasion and metastases in nude mice. Results from microarrays comparing control to caMEK-expressing IECs identified the gene encoding for serpinE2, a serine protease inhibitor, as a potential target of activated MEK1. RESULTS: 1- RT-PCR and western blot analyses confirmed the strong up-regulation of serpinE2 expression and secretion by IECs expressing oncogenic MEK, Ras or BRAF. 2- Interestingly, serpinE2 mRNA and protein were also markedly enhanced in human CRC cells exhibiting mutation in KRAS and BRAF. 3- RNAi directed against serpinE2 in caMEK-transformed rat IECs or in human CRC cell lines HCT116 and LoVo markedly decreased foci formation, anchorage-independent growth in soft agarose, cell migration and tumor formation in nude mice. 4- Treatment of CRC cell lines with U0126 markedly reduced serpinE2 mRNA levels, indicating that expression of serpinE2 is likely dependent of ERK activity. 5- Finally, Q-PCR analyses demonstrated that mRNA levels of serpinE2 were markedly increased in human adenomas in comparison to healthy adjacent tissues and in colorectal tumors, regardless of tumor stage and grade. CONCLUSIONS: Our data indicate that serpinE2 is up-regulated by oncogenic activation of Ras, BRAF and MEK1 and contributes to pro-neoplastic actions of ERK signaling in intestinal epithelial cells. Hence, serpinE2 may be a potential therapeutic target for colorectal cancer treatment.


Assuntos
Neoplasias Colorretais/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Serpina E2/metabolismo , Animais , Western Blotting , Butadienos/farmacologia , Linhagem Celular Tumoral , Neoplasias Colorretais/genética , Inibidores Enzimáticos/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/genética , Células HCT116 , Humanos , Técnicas In Vitro , MAP Quinase Quinase 1/genética , MAP Quinase Quinase 1/metabolismo , Camundongos , Camundongos Nus , Nitrilas/farmacologia , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/metabolismo , Interferência de RNA , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Serpina E2/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Proteínas ras/genética , Proteínas ras/metabolismo
9.
Int J Cancer ; 125(7): 1575-86, 2009 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-19462441

RESUMO

Constitutive activation of the MAP kinase kinase MEK1 induces oncogenic transformation in intestinal epithelial cells. Loss of cell-cell adhesion followed by the dissociation of epithelial structures is a prerequisite for increased cell motility and tumor invasion. This phenotypic switch is designated epithelial-to-mesenchymal transition (EMT). EMT also plays an important role in determining the dissemination of tumors. However, the role of MEK1 in intestinal EMT, tumor invasion and metastasis has not been elucidated. To determine the functions of activated MEK1 in intestinal tumorigenesis, we established intestinal epithelial cell lines that overexpress wild-type MEK1 (wtMEK) or activated MEK1 (caMEK). Our results indicate that expression of caMEK is sufficient to induce EMT as confirmed with the induction of N-cadherin, vimentin, Snail1 and Snail2, whereas a reduction in E-cadherin, occludin, ZO-1 and cortical F-actin was noted. The Snail1 and Snail2 promoter analyses revealed that Egr-1 and Fra-1, an AP-1 protein, are responsible for MEK1-induced Snail1 and Snail2 expression, respectively. Cells expressing activated MEK1 clearly acquired an invasive capacity when compared to wtMEK-expressing cells. Zymography studies confirmed elevated levels of MMP2 and MMP9 activities in media of caMEK-expressing cells. Importantly, cells expressing activated MEK1 induced tumors with short latency in correlation with their ability to induce experimental metastasis in vivo and to express factors known to promote colorectal cancer cell metastasis. In conclusion, our results demonstrate, for the first time, that constitutive activation of MEK1 in intestinal epithelial cells is sufficient to induce an EMT associated with tumor invasion and metastasis.


Assuntos
Transformação Celular Neoplásica/metabolismo , Células Epiteliais/patologia , MAP Quinase Quinase 1/metabolismo , Mesoderma/patologia , Invasividade Neoplásica , Metástase Neoplásica , Animais , Imunoprecipitação da Cromatina , Neoplasias Colorretais/metabolismo , Células Epiteliais/enzimologia , Imunofluorescência , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Intestinos , MAP Quinase Quinase 1/genética , Sistema de Sinalização das MAP Quinases , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Mesoderma/enzimologia , Camundongos , Camundongos Nus , Mutação , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Fatores de Transcrição da Família Snail , Fatores de Transcrição/metabolismo
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