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1.
Photochem Photobiol Sci ; 16(9): 1349-1370, 2017 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-28848959

RESUMO

The UV Index was established more than 20 years ago as a tool for sun protection and health care. Shortly after its introduction, UV Index monitoring started in several countries either by newly acquired instruments or by converting measurements from existing instruments into the UV Index. The number of stations and networks has increased over the years. Currently, 160 stations in 25 European countries deliver online values to the public via the Internet. In this paper an overview of these UV Index monitoring sites in Europe is given. The overview includes instruments as well as quality assurance and quality control procedures. Furthermore, some examples are given about how UV Index values are presented to the public. Through these efforts, 57% of the European population is supplied with high quality information, enabling them to adapt behaviour. Although health care, including skin cancer prevention, is cost-effective, a proportion of the European population still doesn't have access to UV Index information.

2.
Nat Commun ; 8: 15840, 2017 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-28643774

RESUMO

The discovery of oestrogen receptor ß (ERß/ESR2) was a landmark discovery. Its reported expression and homology with breast cancer pharmacological target ERα (ESR1) raised hopes for improved endocrine therapies. After 20 years of intense research, this has not materialized. We here perform a rigorous validation of 13 anti-ERß antibodies, using well-characterized controls and a panel of validation methods. We conclude that only one antibody, the rarely used monoclonal PPZ0506, specifically targets ERß in immunohistochemistry. Applying this antibody for protein expression profiling in 44 normal and 21 malignant human tissues, we detect ERß protein in testis, ovary, lymphoid cells, granulosa cell tumours, and a subset of malignant melanoma and thyroid cancers. We do not find evidence of expression in normal or cancerous human breast. This expression pattern aligns well with RNA-seq data, but contradicts a multitude of studies. Our study highlights how inadequately validated antibodies can lead an exciting field astray.


Assuntos
Anticorpos/análise , Receptor beta de Estrogênio/análise , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Linhagem Celular , Receptor beta de Estrogênio/genética , Receptor beta de Estrogênio/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Linfócitos/química , Linfócitos/metabolismo , Masculino , Ovário/química , Ovário/metabolismo , Testículo/química , Testículo/metabolismo
3.
Oncotarget ; 6(33): 34178-90, 2015 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-26497557

RESUMO

5-azacytidine (5-aza) is a hypomethylating agent approved for the treatment of high-risk myelodysplastic syndrome (MDS). It is assumed to act by demethylating tumor suppressor genes and via direct cytotoxic effects on malignant cells. In vitro treatment with hypomethylating agents has profound effects on the expression of killer-cell immunoglobulin-like (KIR) receptors on natural killer (NK) cells, as these receptors are epigenetically regulated via methylation of the promoters. Here we investigated the influence of 5-aza on the NK-cell repertoire during cytokine-induced proliferation in vitro and homeostatic proliferation in vivo in patients with high-risk MDS. In vitro treatment of NK cells from both healthy donors and MDS patients with low doses of 5-aza led to a significant increase in expression of multiple KIRs, but only in cells that had undergone several rounds of cell division. Proliferating 5-aza exposed NK cells exhibited increased IFN-γ production and degranulation towards tumor target cells. MDS patients had lower proportions of educated KIR-expressing NK cells than healthy controls but after systemic treatment with 5-aza, an increased proportion of Ki-67+ NK cells expressed multiple KIRs suggesting uptake of 5-aza in cycling cells in vivo. Hence, these results suggest that systemic treatment with 5-aza may shape the NK cell repertoire, in particular during homeostatic proliferation, thereby boosting NK cell-mediated recognition of malignant cells.


Assuntos
Antimetabólitos Antineoplásicos/uso terapêutico , Azacitidina/uso terapêutico , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/imunologia , Síndromes Mielodisplásicas/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Feminino , Citometria de Fluxo , Humanos , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/imunologia , Receptores KIR/biossíntese
4.
PLoS One ; 10(5): e0126688, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25978773

RESUMO

The serglycin proteoglycan is mainly expressed by hematopoietic cells where the major function is to retain the content of storage granules and vesicles. In recent years, expression of serglycin has also been found in different forms of human malignancies and a high serglycin expression level has been correlated with a more migratory and invasive phenotype in the case of breast cancer and nasopharyngeal carcinoma. Serglycin has also been implicated in the development of the tumor vasculature in multiple myeloma and hepatocellular carcinoma where reduced expression of serglycin was correlated with a less extensive vasculature. To further investigate the contribution of serglycin to tumor development, we have used the immunocompetent RIP1-Tag2 mouse model of spontaneous insulinoma formation crossed into serglycin deficient mice. For the first time we show that serglycin-deficiency affects orthotopic primary tumor growth and tumor vascular functionality of late stage carcinomas. RIP1-Tag2 mice that lack serglycin develop larger tumors with a higher proliferative activity but unaltered apoptosis compared to normal RIP1-Tag2 mice. The absence of serglycin also enhances the tumor vessel functionality, which is better perfused than in tumors from serglycin wild type mice. The presence of the pro-angiogenic modulators vascular endothelial growth factor and hepatocyte growth factor were decreased in the serglycin deficient mice which suggests a less pro-angiogenic environment in the tumors of these animals. Taken together, we conclude that serglycin affects multiple aspects of spontaneous tumor formation, which strengthens the theory that serglycin acts as an important mediator in the formation and progression of tumors.


Assuntos
Proteínas Ativadoras de GTPase/genética , Insulinoma/genética , Insulinoma/patologia , Neovascularização Patológica/genética , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Proteoglicanas/genética , Proteínas de Transporte Vesicular/genética , Animais , Apoptose/genética , Linhagem Celular Tumoral , Modelos Animais de Doenças , Progressão da Doença , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mieloma Múltiplo/genética , Mieloma Múltiplo/patologia , Neovascularização Patológica/patologia , Fenômenos Fisiológicos/genética , Fator A de Crescimento do Endotélio Vascular/genética
5.
PLoS One ; 9(12): e115911, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25541736

RESUMO

BACKGROUND: The sequencing of the human genome has opened doors for global gene expression profiling, and the immense amount of data will lay an important ground for future studies of normal and diseased tissues. The Human Protein Atlas project aims to systematically map the human gene and protein expression landscape in a multitude of normal healthy tissues as well as cancers, enabling the characterization of both housekeeping genes and genes that display a tissue-specific expression pattern. This article focuses on identifying and describing genes with an elevated expression in four lymphohematopoietic tissue types (bone marrow, lymph node, spleen and appendix), based on the Human Protein Atlas-strategy that combines high throughput transcriptomics with affinity-based proteomics. RESULTS: An enriched or enhanced expression in one or more of the lymphohematopoietic tissues, compared to other tissue-types, was seen for 693 out of 20,050 genes, and the highest levels of expression were found in bone marrow for neutrophilic and erythrocytic genes. A majority of these genes were found to constitute well-characterized genes with known functions in lymphatic or hematopoietic cells, while others are not previously studied, as exemplified by C19ORF59. CONCLUSIONS: In this paper we present a strategy of combining next generation RNA-sequencing with in situ affinity-based proteomics in order to identify and describe new gene targets for further research on lymphatic or hematopoietic cells and tissues. The results constitute lists of genes with enriched or enhanced expression in the four lymphohematopoietic tissues, exemplified also on protein level with immunohistochemical images.


Assuntos
Apêndice/metabolismo , Medula Óssea/metabolismo , Perfilação da Expressão Gênica , Linfonodos/metabolismo , Proteômica , Baço/metabolismo , Perfilação da Expressão Gênica/métodos , Genoma Humano , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Proteoma/análise , Proteoma/genética , Proteômica/métodos , Transcriptoma
6.
PLoS One ; 7(3): e32927, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22412953

RESUMO

Tissue localization of gene expression is increasingly important for accurate interpretation of large scale datasets from expression and mutational analyses. To this end, we have (1) developed a robust and scalable procedure for generation of mRNA hybridization probes, providing >95% first-pass success rate in probe generation to any human target gene and (2) adopted an automated staining procedure for analyses of formalin-fixed paraffin-embedded tissues and tissue microarrays. The in situ mRNA and protein expression patterns for genes with known as well as unknown tissue expression patterns were analyzed in normal and malignant tissues to assess procedure specificity and whether in situ hybridization can be used for validating novel antibodies. We demonstrate concordance between in situ transcript and protein expression patterns of the well-known pathology biomarkers KRT17, CHGA, MKI67, PECAM1 and VIL1, and provide independent validation for novel antibodies to the biomarkers BRD1, EZH2, JUP and SATB2. The present study provides a foundation for comprehensive in situ gene set or transcriptome analyses of human normal and tumor tissues.


Assuntos
Biomarcadores Tumorais/genética , Hibridização In Situ/métodos , Neoplasias/genética , Análise Serial de Tecidos/métodos , Biomarcadores/metabolismo , Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Humanos , Imuno-Histoquímica , Proteínas de Ligação à Região de Interação com a Matriz/genética , Proteínas de Ligação à Região de Interação com a Matriz/metabolismo , Neoplasias/metabolismo , Neoplasias/patologia , Especificidade de Órgãos/genética , Reprodutibilidade dos Testes , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
7.
EMBO Rep ; 13(3): 244-50, 2012 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-22261717

RESUMO

Recent findings suggest that nuclear IGF1R binds to enhancer regions and functions as a transcriptional cofactor. However, the downstream transcriptional regulators of this pathway remain to be defined. Here, we show that nuclear IGF1R associates with the transcription factor LEF1 and increases promoter activity of LEF1 downstream target genes cyclin D1 and axin2. Furthermore, nuclear IGF1R augments protein levels of cyclin D1 and axin2. Our findings suggest a novel function for IGF1R, thus further emphasizing the important role of this receptor in cancer biology.


Assuntos
Fator 1 de Ligação ao Facilitador Linfoide/metabolismo , Receptor IGF Tipo 1/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Ativação Transcricional/fisiologia , Proteína Axina/genética , Proteína Axina/metabolismo , Linhagem Celular , Núcleo Celular/metabolismo , Ciclina D1/genética , Ciclina D1/metabolismo , Regulação da Expressão Gênica , Humanos , Proteínas Substratos do Receptor de Insulina/metabolismo , Regiões Promotoras Genéticas , Ligação Proteica , Transporte Proteico , Receptor IGF Tipo 1/genética , beta Catenina/metabolismo
8.
Blood ; 116(19): 3853-64, 2010 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-20696944

RESUMO

Natural killer (NK) cells are lymphocytes of the innate immune system that, following differentiation from CD56(bright) to CD56(dim) cells, have been thought to retain fixed functional and phenotypic properties throughout their lifespan. In contrast to this notion, we here show that CD56(dim) NK cells continue to differentiate. During this process, they lose expression of NKG2A, sequentially acquire inhibitory killer cell inhibitory immunoglobulin-like receptors and CD57, change their expression patterns of homing molecules, and display a gradual decline in proliferative capacity. All cellular intermediates of this process are represented in varying proportions at steady state and appear, over time, during the reconstitution of the immune system, as demonstrated in humanized mice and in patients undergoing hematopoietic stem cell transplantation. CD56(dim) NK-cell differentiation, and the associated functional imprint, occurs independently of NK-cell education by interactions with self-human leukocyte antigen class I ligands and is an essential part of the formation of human NK-cell repertoires.


Assuntos
Antígeno CD56/metabolismo , Antígenos CD57/metabolismo , Células Matadoras Naturais/citologia , Células Matadoras Naturais/imunologia , Subfamília C de Receptores Semelhantes a Lectina de Células NK/metabolismo , Receptores KIR/metabolismo , Animais , Diferenciação Celular , Proliferação de Células , Transplante de Células-Tronco Hematopoéticas , Humanos , Técnicas In Vitro , Células Matadoras Naturais/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Fenótipo , Transplante Heterólogo
9.
Exp Cell Res ; 316(8): 1309-15, 2010 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-20206161

RESUMO

Natural killer (NK) cells are innate lymphocytes that participate in the early control of viruses and tumors. The function of NK cells is under tight regulation by two complementary inhibitory receptor families that bind to classical and non-classical HLA class I molecules: the CD94/NKG2A receptors and the killer cell immunoglobulin-like receptors (KIRs). In this mini-review, recent data on the structure of human NK cell receptor repertoires and its relation to functional responses and tolerance to self are discussed. We propose that no active selection is required to generate diverse NK cell repertoires characterized by a dominant expression of receptors with specificity for self-HLA class I. Instead, the primary consequence of interactions with HLA class I molecules is a functional tuning of randomly generated NK cell repertoires.


Assuntos
Tolerância Imunológica , Células Matadoras Naturais/imunologia , Animais , Antígenos de Histocompatibilidade Classe I/metabolismo , Humanos , Subfamília D de Receptores Semelhantes a Lectina de Células NK/metabolismo , Receptores KIR/metabolismo
10.
Neuro Oncol ; 12(1): 19-27, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20150364

RESUMO

Glioblastoma (GB) is the most common malignant brain tumor in adults. It has limited treatment opportunities and is almost exclusively fatal. Owing to the central role the insulin-like growth factor-1 receptor (IGF-1R) plays in malignant cells, it has been suggested as a target for anticancer therapy including GB. The cyclolignan picropodophyllin (PPP) inhibits IGF-1R without affecting the highly homologous insulin receptor. Here, we show that PPP inhibits growth of human GB cell lines along with reduced phosphorylation of IGF-1R and AKT. In vivo, PPP-treatment causes dramatic tumor regression not only in subcutaneous xenografts but also in intracerebral xenografts, indicating passage of PPP across the blood-brain barrier.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Podofilotoxina/análogos & derivados , Receptor IGF Tipo 1/antagonistas & inibidores , Animais , Apoptose/efeitos dos fármacos , Western Blotting , Linhagem Celular Tumoral , Humanos , Imunoprecipitação , Camundongos , Camundongos SCID , Podofilotoxina/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto
11.
BJU Int ; 104(11): 1780-5, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19522865

RESUMO

OBJECTIVE: To screen a publicly available immunohistochemistry (IHC) based web-atlas, to identify key proteins in bladder cancer that might serve as potential biomarkers. MATERIALS AND METHODS: The first version of the Human Protein Atlas (HPA 1.0), with 660 proteins, was visually examined to identify proteins with a variable staining pattern among the 12 tissue samples representing bladder cancer. None or limited previous characterization in bladder cancer, as well as a supportive Western blot, were also required. The selected proteins were then evaluated in an independent set of patient samples (106 tumour samples of differing stage and grade) represented in a tissue microarray (TMAi). The IHC expression of the identified proteins in the TMAi was scored and related to tumour stage and grade. RESULTS: The expression profiles of the 13 proteins selected from the web-atlas were confirmed in the TMAi. Expression patterns for seven proteins were significantly altered (P < 0.05) with higher stage and/or grade. Three of those (CN130, DSG3, PHF6) lack characterization in bladder cancer, whereas the remaining four proteins have previously been suggested as key proteins/potential biomarkers in cancer, some of them also in bladder cancer. CONCLUSION: New candidate proteins for urinary bladder cancer were identified through screening of the publicly available HPA 1.0. Although further evaluation is necessary, this strategy is promising in the search for new biomarkers, with potential to improve the management of patients with this disease.


Assuntos
Biomarcadores Tumorais/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias da Bexiga Urinária/diagnóstico , Western Blotting , Humanos , Imuno-Histoquímica , Análise Serial de Proteínas , Análise Serial de Tecidos , Neoplasias da Bexiga Urinária/metabolismo
12.
Biochem Biophys Res Commun ; 387(1): 36-41, 2009 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-19545541

RESUMO

Recent studies have shown a direct association between IGF-1R and FAK, two important mediators of cell growth, survival and migration. However, the mechanism by which FAK affects IGF-1R function remains unknown. This study investigates the potential role of FAK in mediating activation and stability of IGF-1R. Autophosphorylation and phosphorylation capacities of wild type and mutant IGF-1R were studied. Surprisingly, we found that the mutant IGF-1R lacking the three core tyrosine residues in the activation-loop can be phosphorylated although it is unable to undergo autophosphorylation, suggesting that another kinase possesses the ability to phosphorylate IGF-1R. By using wild type MEFs and FAK-/- MEFs we could demonstrate that FAK mediates activation-loop independent phosphorylation, as well as Akt and ERK activation. Furthermore, the stability of IGF-1R was decreased upon FAK siRNA or inactivation. Taken together, our data suggest a role for FAK in phosphorylation, signaling and stability of the IGF-1R.


Assuntos
Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Receptor IGF Tipo 1/agonistas , Linhagem Celular Tumoral , Estabilidade Enzimática , Proteína-Tirosina Quinases de Adesão Focal/genética , Humanos , Ligantes , Fosforilação , RNA Interferente Pequeno/genética , Receptor IGF Tipo 1/genética , Receptor IGF Tipo 1/metabolismo
13.
Acta Ophthalmol ; 86 Thesis 4: 35-41, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19032680

RESUMO

PURPOSE: The cyclolignan picropodophyllin (PPP) efficiently blocks the activity of insulin-like growth factor-1 receptor (IGF-1R) and inhibits growth of uveal melanoma cells in vitro and in vivo. In this study, we aimed to investigate the efficiency of orally administered PPP on growth of uveal melanoma xenografts. Further, we focused on the effect of PPP on vascular endothelial growth factor (VEGF) in vivo and evaluated its effects in combination with other established anti-tumor agents in vitro. METHODS: Four different uveal melanoma cell lines (OCM-1, OCM-3, OCM-8, 92-1) were treated with PPP alone and in combination with imatinib mesylate, cisplatin, 5-FU and doxorubicin. Cell viability was determined by XTT assay. SCID mice xenografted with uveal melanoma cells were used to determine anti-tumor efficacy of oral PPP in vivo. Tumor samples obtained from the in vivo experiments were analyzed for VEGF and IGF-1R expression by western blotting. RESULTS: PPP was found to be superior to the other anti-tumor agents in killing uveal melanoma cells. Oral PPP inhibited uveal melanoma growth in vivo and was well tolerated by the animals. PPP decreased VEGF expression in the tumors. CONCLUSIONS: Oral PPP is well tolerated in vivo and caused total growth inhibition of uveal melanoma xenografts as well as it decreased the levels of VEGF in the tumors.


Assuntos
Melanoma/metabolismo , Melanoma/patologia , Podofilotoxina/análogos & derivados , Receptor IGF Tipo 1/antagonistas & inibidores , Neoplasias Uveais/metabolismo , Neoplasias Uveais/patologia , Administração Oral , Animais , Antineoplásicos/farmacologia , Morte Celular , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Melanoma/fisiopatologia , Camundongos , Camundongos SCID , Transplante de Neoplasias , Podofilotoxina/administração & dosagem , Podofilotoxina/farmacologia , Transplante Heterólogo , Neoplasias Uveais/fisiopatologia , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores
14.
J Immunol ; 181(9): 6010-9, 2008 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-18941190

RESUMO

Stem cell transplantation across HLA barriers may trigger NK cell-mediated graft-vs-leukemia effects leading to improved survival for patients with hematological malignancies. However, the genetic algorithm based on killer cell Ig-like receptor (KIR) and HLA genes used to predict NK cell alloreactivity have yielded discrepant results. Accordingly, it has been difficult to define transplantation settings that favor NK cell alloreactivity. In this study, we have used multiparameter flow cytometry to simultaneously analyze the cell surface expression of all four major inhibitory KIR and CD94/NKG2A to determine the size of the alloreactive NK cell repertoires in 31 individuals homozygous for the group A KIR haplotype. We observed a vast variability in the frequencies of cells with an alloreactive potential, ranging from 0 to 62% of the total NK cell population depending on which, and how many, KIR ligands were missing in theoretical recipients. This analysis required a functional examination of KIR3DL2-single positive NK cells, showing that this subset was hyporesponsive in individuals harboring the cognate ligands HLA-A3/A11. The results provide new insights into the variability of the functional alloreactive NK cell repertoire and have implications for donor selection in hematopoietic stem cell transplantation and adoptive NK cell-based immunotherapy.


Assuntos
Haplótipos , Teste de Histocompatibilidade , Homozigoto , Células Matadoras Naturais/citologia , Células Matadoras Naturais/imunologia , Receptores KIR3DL2/genética , Anticorpos Monoclonais/metabolismo , Testes Imunológicos de Citotoxicidade , Genótipo , Efeito Enxerto vs Leucemia/genética , Efeito Enxerto vs Leucemia/imunologia , Antígenos HLA-A/metabolismo , Antígeno HLA-A11 , Antígeno HLA-A3/metabolismo , Teste de Histocompatibilidade/métodos , Humanos , Células K562 , Células Matadoras Naturais/metabolismo , Ligantes , Subfamília C de Receptores Semelhantes a Lectina de Células NK/biossíntese , Subfamília C de Receptores Semelhantes a Lectina de Células NK/genética , Subfamília C de Receptores Semelhantes a Lectina de Células NK/imunologia , Subfamília C de Receptores Semelhantes a Lectina de Células NK/metabolismo , Receptores KIR3DL2/biossíntese , Receptores KIR3DL2/imunologia , Receptores KIR3DL2/metabolismo , Transplante de Células-Tronco
15.
Cancer Res ; 68(14): 5669-77, 2008 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-18632619

RESUMO

The insulin-like growth factor receptor (IGF-IR) plays several pivotal roles in cancer. Although most studies on the function of the IGF-IR have been attributed to kinase-dependent signaling, recent findings by our group and others have implicated biological roles mediated by ubiquitination of the receptor. As previously reported, the E3 ligases Mdm2 and Nedd4 mediate IGF-IR ubiquitination. Here we show that c-Cbl is a novel E3 ligase for IGF-IR. On ligand stimulation, both Mdm2 and c-Cbl associate with IGF-IR and mediate receptor polyubiquitination. Whereas Mdm2 catalyzed lysine 63 (K63) chain ubiquitination, c-Cbl modified IGF-IR through K48 chains. Mdm2-mediated ubiquitination occurred when cells were stimulated with a low concentration (5 ng/mL) of IGF-I, whereas c-Cbl required high concentrations (50-100 ng/mL). Mdm2-ubiquitinated IGF-IR was internalized through the clathrin endocytic pathway whereas c-Cbl-ubiquitinated receptors were endocytosed via the caveolin route. Taken together, our results show that c-Cbl constitutes a new ligase responsible for the ubiquitination of IGF-IR and that it complements the action of Mdm2 on ubiquitin lysine residue specificity, responsiveness to IGF-I, and type of endocytic pathway used. The actions and interactions of Mdm2 and c-Cbl in the ubiquitination and endocytosis of IGF-IR may have implications in cancer. In addition, identification and functional characterization of new E3 ligases are important in itself because therapeutic targeting of substrate-specific E3 ligases is likely to represent a critical strategy in future cancer treatment.


Assuntos
Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Proteínas Proto-Oncogênicas c-cbl/fisiologia , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Receptor IGF Tipo 1/metabolismo , Ubiquitina/metabolismo , Linhagem Celular Tumoral , Endocitose , Complexos Endossomais de Distribuição Requeridos para Transporte , Humanos , Microscopia Confocal , Modelos Biológicos , Ubiquitina-Proteína Ligases Nedd4 , Neoplasias/metabolismo , Proteínas Proto-Oncogênicas c-cbl/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
16.
Invest Ophthalmol Vis Sci ; 49(6): 2337-42, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18515579

RESUMO

PURPOSE: The cyclolignan picropodophyllin (PPP) efficiently blocks the activity of insulinlike growth factor-1 receptor (IGF-1R) and inhibits the growth of uveal melanoma cells in vitro and in vivo. In this study, the authors investigated the efficiency of orally administered PPP on the growth of uveal melanoma xenografts. In addition, they focused on the effect of PPP on vascular endothelial growth factor (VEGF) in vivo and evaluated its effects in combination with other established antitumor agents in vitro. METHODS: Four different uveal melanoma cell lines (OCM-1, OCM-3, OCM-8, 92-1) were treated with PPP alone and in combination with imatinib mesylate, cisplatin, 5-fluorouracil, and doxorubicin. Cell viability was determined by XTT assay. SCID mice that underwent xenografting with uveal melanoma cells were used to determine antitumor efficacy of oral PPP in vivo. Five mice were used per group. Tumor samples obtained from the in vivo experiments were analyzed for VEGF and IGF-1R expression by Western blotting. RESULTS: PPP was found to be superior to the other antitumor agents in killing uveal melanoma cells in all four cell lines (IC50 < 0.05 microM). Oral PPP inhibited uveal melanoma growth in vivo in OCM-3 (P = 0.03) and OCM-8 (P = 0.01) xenografts and was well tolerated by the animals. PPP decreased VEGF expression in the OCM-1 (P = 0.006) and OCM-8 (P = 0.01) tumors. CONCLUSIONS: Oral PPP was well tolerated in vivo, caused total growth inhibition of uveal melanoma xenografts, and decreased VEGF levels in the tumors.


Assuntos
Antineoplásicos Fitogênicos/administração & dosagem , Proliferação de Células/efeitos dos fármacos , Melanoma/prevenção & controle , Podofilotoxina/análogos & derivados , Receptor IGF Tipo 1/antagonistas & inibidores , Neoplasias Uveais/prevenção & controle , Administração Oral , Animais , Antineoplásicos Fitogênicos/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Western Blotting , Sobrevivência Celular/efeitos dos fármacos , Humanos , Melanoma/metabolismo , Melanoma/patologia , Camundongos , Camundongos SCID , Transplante de Neoplasias , Podofilotoxina/administração & dosagem , Podofilotoxina/efeitos adversos , Receptor IGF Tipo 1/metabolismo , Organismos Livres de Patógenos Específicos , Transplante Heterólogo , Células Tumorais Cultivadas/efeitos dos fármacos , Neoplasias Uveais/metabolismo , Neoplasias Uveais/patologia , Fator A de Crescimento do Endotélio Vascular/metabolismo
17.
Cancer Immunol Immunother ; 57(10): 1541-52, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18317755

RESUMO

Insights into the molecular basis for natural killer (NK) cell recognition of human cancer have been obtained in recent years. Here, we review current knowledge on the molecular specificity and function of human NK cells. Evidence for NK cell targeting of human tumors is provided and new strategies for NK cell-based immunotherapy against human cancer are discussed. Based on current knowledge, we foresee a development where more cancers may be subject to treatment with drugs or other immunomodulatory agents affecting NK cells, either directly or indirectly. We also envisage a possibility that certain forms of cancers may be subject to treatment with adoptively transferred NK cells, either alone or in combination with other therapeutic interventions.


Assuntos
Citotoxicidade Imunológica , Imunoterapia/métodos , Células Matadoras Naturais/imunologia , Neoplasias/imunologia , Neoplasias/terapia , Humanos
18.
J Endocrinol ; 196(3): 547-57, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18310450

RESUMO

Obesity has become a major health problem in many parts of the world. Estrogens are known to reduce adipose tissue mass in both humans and animals but the molecular mechanisms are not well characterized. We used gene expression profiling to study long-term effects of estrogen on gene expression in mouse white adipose tissue and hypothalamus. Overall, the effects of estrogen on hypothalamic gene expression were much smaller than the corresponding effects on white adipose tissue gene expression. We characterize in detail estrogenic regulation of glutathione peroxidase 3 (GPX3). Our studies suggest that GPX3 is a direct estrogen receptor alpha target gene in white adipose tissue. Since obesity is correlated with oxidative stress, and GPX3 has been demonstrated to be lower in obesity and higher after weight loss, we hypothesize that GPX3 is one important mediator of effects of estrogen in relation to fat mass. Additional genes that were affected by estrogen in adipose tissue include cell death-inducing DNA fragmentation factor, alpha-subunit-like effector A (CIDEA), a gene shown to be related to body fat in mice. We conclude that estrogen has large effects on gene expression in white adipose tissue and hypothesize that GPX3 and CIDEA could be important mediators of the effects of estrogen on fat mass.


Assuntos
Tecido Adiposo Branco/fisiologia , Proteínas Reguladoras de Apoptose/genética , Estradiol/fisiologia , Perfilação da Expressão Gênica , Glutationa Peroxidase/genética , Hipotálamo/fisiologia , Animais , Fragmentação do DNA/efeitos dos fármacos , Estradiol/farmacologia , Feminino , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/genética , Obesidade/fisiopatologia , Análise de Sequência com Séries de Oligonucleotídeos , Ovariectomia , Estresse Oxidativo/fisiologia , RNA Mensageiro/metabolismo
19.
Physiol Rev ; 87(3): 905-31, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17615392

RESUMO

During the past decade there has been a substantial advance in our understanding of estrogen signaling both from a clinical as well as a preclinical perspective. Estrogen signaling is a balance between two opposing forces in the form of two distinct receptors (ER alpha and ER beta) and their splice variants. The prospect that these two pathways can be selectively stimulated or inhibited with subtype-selective drugs constitutes new and promising therapeutic opportunities in clinical areas as diverse as hormone replacement, autoimmune diseases, prostate and breast cancer, and depression. Molecular biological, biochemical, and structural studies have generated information which is invaluable for the development of more selective and effective ER ligands. We have also become aware that ERs do not function by themselves but require a number of coregulatory proteins whose cell-specific expression explains some of the distinct cellular actions of estrogen. Estrogen is an important morphogen, and many of its proliferative effects on the epithelial compartment of glands are mediated by growth factors secreted from the stromal compartment. Thus understanding the cross-talk between growth factor and estrogen signaling is essential for understanding both normal and malignant growth. In this review we focus on several of the interesting recent discoveries concerning estrogen receptors, on estrogen as a morphogen, and on the molecular mechanisms of anti-estrogen signaling.


Assuntos
Receptores de Estrogênio/metabolismo , Transdução de Sinais , Animais , Estrogênios/química , Estrogênios/farmacologia , Feminino , Humanos , Isoformas de Proteínas , Receptores de Estrogênio/antagonistas & inibidores
20.
PLoS One ; 2(4): e340, 2007 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-17406664

RESUMO

BACKGROUND: The insulin-like growth factor 1 receptor (IGF-1R) plays numerous crucial roles in cancer biology. The majority of knowledge on IGF-1R signaling is concerned with its role in the activation of the canonical phosphatidyl inositol-3 kinase (PI3K)/Akt and MAPK/ERK pathways. However, the role of IGF-1R ubiquitination in modulating IGF-1R function is an area of current research. In light of this we sought to determine the relationship between IGF-1R phosphorylation, ubiquitination, and modulation of growth signals. METHODOLOGY: Wild type and mutant constructs of IGF-1R were transfected into IGF-1R null fibroblasts. IGF-1R autophosphorylation and ubiquitination were determined by immunoprecipitation and western blotting. IGF-1R degradation and stability was determined by cyclohexamide-chase assay in combination with lysosome and proteasome inhibitors. PRINCIPAL FINDINGS: IGF-1R autophosphorylation was found to be an absolute requirement for receptor ubiquitination. Deletion of C-terminal domain had minimal effect on IGF-1 induced receptor autophosphorylation, however, ubiquitination and ERK activation were completely abolished. Cells expressing kinase impaired IGF-1R, exhibited both receptor ubiquitination and ERK phosphorylation, however failed to activate Akt. While IGF-1R mutants with impaired PI3K/Akt signaling were degraded mainly by the proteasomes, the C-terminal truncated one was exclusively degraded through the lysosomal pathway. CONCLUSIONS: Our data suggest important roles of ubiquitination in mediating IGF-1R signaling and degradation. Ubiquitination of IGF-1R requires receptor tyrosine kinase activity, but is not involved in Akt activation. In addition we show that the C-terminal domain of IGF-1R is a necessary requisite for ubiquitination and ERK phosphorylation as well as for proteasomal degradation of the receptor.


Assuntos
Receptor IGF Tipo 1/metabolismo , Transdução de Sinais , Ubiquitinação , Animais , Ativação Enzimática , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Hidrólise , Imunoprecipitação , Camundongos , Camundongos Knockout , Fosforilação , Receptor IGF Tipo 1/genética
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