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1.
Asian Pac J Cancer Prev ; 24(10): 3629-3636, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37898872

RESUMO

OBJECTIVE: This study investigates the association between HLA-A and -B allele diversity, Fusobacterium nucleatum Fap2 protein-derived antigenic coverage, and colorectal cancer (CRC) epidemiology across diverse populations. METHODS: We examined 75 HLA-I alleles and explored 698 potential HLA-A and B-restricted Fap2-derived antigens, assessing how 21 countries may respond to these peptides based on their HLA-I distribution frequencies. Additionally, we correlated in-silico predicted Fap2 population coverage with CRC epidemiology. CRC incidence and mortality data were obtained from the Global Cancer Observatory, and HLA-A and HLA-B allele frequencies from the Allele Frequency Net Database. Binding predictions for Fap2 antigens were performed using netMHCpan4, with stringent selection criteria applied to identify relevant peptides. Population coverage was calculated using the IEDB population coverage tool, and data analysis conducted using the R programming language. RESULTS: Clustering of HLA-A and -B allele frequencies partially differentiated countries with lower CRC incidence from others. Distinct patterns of Fap2 protein coverage were observed among different populations. interestingly, we found a significant inverse correlation between CRC incidence (p = 0.0037, R = -0.6) and predicted Fap2 antigen coverage, as well as CRC mortality (p = 0.013, R = -0.53). Furthermore, we identified a specific set of Fap2-derived peptides that bind to HLA supertypes, providing a global coverage of 99.04%. CONCLUSION: Our population-based study is the first to demonstrate that higher Fap2 coverage is associated with lower CRC incidence, underscoring the potential significance of Fap2-specific CD8+ T cell responses in CRC tumorigenesis.


Assuntos
Neoplasias Colorretais , Fusobacterium nucleatum , Humanos , Fusobacterium nucleatum/genética , Alelos , Incidência , Peptídeos , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/genética , Antígenos HLA-A
2.
Artigo em Inglês | MEDLINE | ID: mdl-31781260

RESUMO

Osteoarthritis (OA) is considered a major cause of disability around the globe. This handicapping disease causes important cartilage and bone alteration that is associated with serious pains and loss of joint function. Despite its frequent association with obesity, the aetiology of OA is not fully understood. In this review, the different aspects of OA and its correlation with obesity were analysed. Through examining different mechanisms by which obesity may trigger and/or exacerbate OA, we point out some relevant signalling pathways that may evolve as candidates for pharmacological drug development. As such, we also suggest a review of different herbal medicines (HMs) and their main compounds, which specifically interfere with the identified pathways. We have shown that obesity's involvement in OA is not only limited to the mechanical weight exerted on the joints (mechanical hypothesis), but also induces an inflammatory state by different mechanisms, including increased leptin expression, compromised gut mucosa, and/or gut microbiota disruption. The main signalling pathways involved in OA inflammation, which are associated with obesity, are protein tyrosine phosphatase 1B (PTP1B) and TLR4 or DAP12. Moreover, we also underline the contamination of plant extracts with LPS as an important factor to consider when studying HM's effects on articular cells. By summarizing recent publications, this review aims at highlighting newly established aspects of obesity involvement in OA other than the mechanical one.

3.
Arthritis Res Ther ; 18(1): 219, 2016 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-27716396

RESUMO

BACKGROUND: Glucocorticoid-induced leucine zipper (GILZ) is a mediator of the anti-inflammatory activities of glucocorticoids. However, GILZ deletion does not impair the anti-inflammatory activities of exogenous glucocorticoids in mice arthritis models and GILZ could also mediate some glucocorticoid-related adverse events. Osteoarthritis (OA) is a metabolic disorder that is partly attributed to adipokines such as leptin, and we previously observed that glucocorticoids induced leptin secretion in OA synovial fibroblasts. The purpose of this study was to position GILZ in OA through its involvement in the anti-inflammatory activities of glucocorticoids and/or in the metabolic pathway of leptin induction. The influences of mineralocorticoids on GILZ and leptin expression were also investigated. METHODS: Human synovial fibroblasts were isolated from OA patients during knee replacement surgery. Then, the cells were treated with a glucocorticoid (prednisolone), a mineralocorticoid (aldosterone), a glucocorticoid receptor (GR) antagonist (mifepristone), a selective glucocorticoid receptor agonist (Compound A), mineralocorticoid receptor (MR) antagonists (eplerenone and spironolactone), TNF-α or transforming growth factor (TGF)-ß. Cells were transfected with shRNA lentiviruses for the silencing of GILZ and GR. The leptin, IL-6, IL-8 and matrix metalloproteinase (MMP)-1 levels were measured by ELISA. Leptin, the leptin receptor (Ob-R), GR and GILZ expression levels were analyzed by western blotting and/or RT-qPCR. RESULTS: (1) The glucocorticoid prednisolone and the mineralocorticoid aldosterone induced GILZ expression dose-dependently in OA synovial fibroblasts, through GR but not MR. Similar effects on leptin and Ob-R were observed: leptin secretion and Ob-R expression were also induced by prednisolone and aldosterone through GR; (2) GILZ silencing experiments demonstrated that GILZ was involved in the glucocorticoid-induced and mineralocorticoid-induced leptin secretion and Ob-R expression in OA synovial fibroblasts; and (3) GILZ inhibition did not alter the production of pro-inflammatory cytokines by OA synovial fibroblast or the anti-inflammatory properties of glucocorticoids. CONCLUSIONS: The absence of GILZ prevents corticoid-induced leptin and Ob-R expression without affecting the anti-inflammatory properties of glucocorticoids in OA synovial fibroblasts. Mineralocorticoids also induce leptin and Ob-R expression through GILZ.


Assuntos
Fibroblastos/metabolismo , Leptina/biossíntese , Osteoartrite do Joelho/metabolismo , Sinoviócitos/metabolismo , Fatores de Transcrição/metabolismo , Idoso , Idoso de 80 Anos ou mais , Aldosterona/farmacologia , Western Blotting , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Feminino , Técnicas de Silenciamento de Genes , Glucocorticoides/farmacologia , Humanos , Masculino , Pessoa de Meia-Idade , Mineralocorticoides/farmacologia , Reação em Cadeia da Polimerase , Prednisolona/farmacologia
4.
Rheumatology (Oxford) ; 54(6): 1087-92, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25389358

RESUMO

OBJECTIVE: Glucocorticoids are powerful anti-inflammatory compounds that also induce the expression of leptin and leptin receptor (Ob-R) in synovial fibroblasts through TGF-ßsignalling and Smad1/5 phosphorylation. Compound A (CpdA), a selective glucocorticoid receptor agonist, reduces inflammation in murine arthritis models and does not induce diabetes or osteoporosis, thus offering an improved risk:benefit ratio in comparison with glucocorticoids. Due to the detrimental role of leptin in OA pathogenesis, we sought to determine whether CpdA also induced leptin and Ob-R protein expression as observed with prednisolone. METHODS: Human synovial fibroblasts and chondrocytes were isolated from the synovium and cartilage of OA patients after joint surgery. The cells were treated with prednisolone, TGF-ß1, TNF-α and/or CpdA. Levels of leptin, IL-6, IL-8, MMP-1 and MMP-3 were measured by ELISA and expression levels of Ob-R phospho-Smad1/5, phospho-Smad2, α-tubulin and glyceraldehyde 3-phosphate dehydrogenase were analysed by western blotting. RESULTS: CpdA, unlike prednisolone, did not induce leptin secretion or Ob-R protein expression in OA synovial fibroblasts. Moreover, CpdA decreased endogenous Ob-R expression and down-regulated prednisolone-induced leptin secretion and Ob-R expression. Mechanistically, CpdA, unlike prednisolone, did not induce Smad1/5 phosphorylation. CpdA, similarly to prednisolone, down-regulated endogenous and TNF-α-induced IL-6, IL-8, MMP-1 and MMP-3 protein secretion. The dissociative effect of CpdA was confirmed using chondrocytes with no induction of leptin secretion, but with a significant decrease in IL-6, IL-8, MMP-1 and MMP-3 protein secretion. CONCLUSION: CpdA, unlike prednisolone, did not induce leptin or Ob-R in human OA synovial fibroblasts, thereby demonstrating an improved risk:benefit ratio.


Assuntos
Condrócitos/metabolismo , Fibroblastos/metabolismo , Osteoartrite/metabolismo , Prednisolona/farmacologia , Receptores de Glucocorticoides/agonistas , Membrana Sinovial/metabolismo , Idoso , Idoso de 80 Anos ou mais , Western Blotting , Condrócitos/efeitos dos fármacos , Ensaio de Imunoadsorção Enzimática , Feminino , Fibroblastos/efeitos dos fármacos , Gliceraldeído-3-Fosfato Desidrogenases/efeitos dos fármacos , Gliceraldeído-3-Fosfato Desidrogenases/metabolismo , Humanos , Interleucina-6/metabolismo , Interleucina-8/efeitos dos fármacos , Interleucina-8/metabolismo , Leptina/metabolismo , Masculino , Metaloproteinase 1 da Matriz/efeitos dos fármacos , Metaloproteinase 1 da Matriz/metabolismo , Metaloproteinase 3 da Matriz/efeitos dos fármacos , Metaloproteinase 3 da Matriz/metabolismo , Pessoa de Meia-Idade , Receptores para Leptina/efeitos dos fármacos , Receptores para Leptina/metabolismo , Proteínas Smad Reguladas por Receptor/efeitos dos fármacos , Proteínas Smad Reguladas por Receptor/metabolismo , Membrana Sinovial/efeitos dos fármacos , Fator de Crescimento Transformador beta1/efeitos dos fármacos , Fator de Crescimento Transformador beta1/metabolismo , Tubulina (Proteína)/efeitos dos fármacos , Tubulina (Proteína)/metabolismo , Fator de Necrose Tumoral alfa/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo
5.
Cytotherapy ; 16(11): 1511-1518, 2014 11.
Artigo em Inglês | MEDLINE | ID: mdl-25174737

RESUMO

This article has been removed: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been removed at the request of the Editor in Chief. This retraction comes after a thorough investigation of the scientific research presented in the article, along with an investigation into the authorship of the article and the ownership of the data presented. The Editor in Chief's decision to retract the article is based upon the authors' misuse and misrepresentation of a peer's scientific data without consent or approval.


Assuntos
Fígado/efeitos dos fármacos , Fígado/metabolismo , Transplante de Células-Tronco Mesenquimais , Cordão Umbilical/citologia , Animais , Células da Medula Óssea/citologia , Células da Medula Óssea/metabolismo , Tetracloreto de Carbono/toxicidade , Humanos , Fígado/lesões , Regeneração Hepática , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Camundongos , Cordão Umbilical/metabolismo , Cordão Umbilical/transplante
6.
World J Stem Cells ; 6(3): 367-70, 2014 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-25126385

RESUMO

In cell therapy protocols, many tissues were proposed as a source of mesenchymal stem cells (MSC) isolation. So far, bone marrow (BM) has been presented as the main source of MSC despite the invasive isolation procedure related to this source. During the last years, the umbilical cord (UC) matrix was cited in different studies as a reliable source from which long term ex vivo proliferating fibroblasts were isolated but with contradictory data about their immunophenotype, gene expression profile, and differentiation potential. Hence, an interesting question emerged: Are cells isolated from cord matrix (UC-MSC) different from other MSCs? In this review, we will summarize different studies that isolated and characterized UC-MSC. Considering BM-MSC as gold standard, we will discuss if UC-MSC fulfill different criteria that define MSC, and what remain to be done in this issue.

7.
Int J Exp Pathol ; 95(4): 251-9, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24738751

RESUMO

Undifferentiated cell Transcription Factor 1 (UTF1) is a chromatin-bound protein involved in stem cell differentiation. It was initially reported to be restricted to stem cells or germinal tissues. However, recent work suggests that UTF1 is also expressed in somatic cells and that its expression may increase during carcinogenesis. To further clarify the expression profile of UTF1, we evaluated UTF1 expression levels immunohistochemically in eight normal human epithelia (from breast, prostate, endometrium, bladder, colon, oesophagus, lung and kidney) and their corresponding tumours as well as in several epithelial cell lines. We showed UTF1 staining in normal and tumour epithelial tissues, but with varying intensities according to the tissue location. In vitro analyses also revealed that UTF1 is expressed in somatic epithelial cell lines even in the absence of Oct4A and Sox2, its two main known regulators. The comparison of UTF1 levels in normal and tumoral tissues revealed significant overexpression in endometrial and prostatic adenocarcinomas, whereas lower intensity of the staining was observed in renal and colic tumours, suggesting a potential tissue-specific function of UTF1. Altogether, these results highlight a potential dual role for UTF1, acting either as an oncogene or as a tumour suppressor depending on the tissue. These findings also question its role as a specific marker for stem cells.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias do Endométrio/metabolismo , Endométrio/metabolismo , Células Epiteliais/metabolismo , Proteínas Nucleares/metabolismo , Próstata/metabolismo , Neoplasias da Próstata/metabolismo , Transativadores/metabolismo , Transcriptoma , Biomarcadores Tumorais/genética , Linhagem Celular Tumoral , Células Cultivadas , Colo/metabolismo , Colo/patologia , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Regulação para Baixo , Neoplasias do Endométrio/patologia , Endométrio/patologia , Células Epiteliais/patologia , Feminino , Humanos , Rim/metabolismo , Rim/patologia , Neoplasias Renais/metabolismo , Neoplasias Renais/patologia , Masculino , Proteínas Nucleares/genética , Fator 3 de Transcrição de Octâmero/genética , Fator 3 de Transcrição de Octâmero/metabolismo , Próstata/patologia , Neoplasias da Próstata/patologia , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXB1/metabolismo , Transativadores/genética , Regulação para Cima
8.
Stem Cells Dev ; 21(11): 1948-55, 2012 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-22087763

RESUMO

Leptin plays a central role in maintaining energy balance, with multiple other systemic effects. Despite leptin importance in peripheral regulation of mesenchymal stem cells (MSC) differentiation, little is known about its expression mechanism. Leptin is often described as adipokine, while it is expressed by other cell types. We have recently shown an in vitro leptin expression, enhanced by glucocorticoids in synovial fibroblasts (SVF). Here, we investigated leptin expression in MSC from bone marrow (BM-MSC) and umbilical cord matrix (UMSC). Results showed that BM-MSC, but not UMSC, expressed leptin that was strongly enhanced by glucocorticoids. Transforming growth factor ß1 (TGF-ß1) markedly inhibited the endogenous- and glucocorticoid-induced leptin expression in BM-MSC. Since TGF-ß1 was shown to signal via ALK-5-Smad2/3 and/or ALK-1-Smad1/5 pathways, we analyzed the expression of proteins from both pathways. In BM-MSC, TGF-ß1 increased phosphorylated Smad2 (p-Smad2) expression, while ALK-5 inhibitor (SB431542) induced leptin expression and significantly restored TGF-ß1-induced leptin inhibition. In addition, both prednisolone and SB431542 increased p-Smad1/5 expression. These results suggested the ALK-5-Smad2 pathway as an inhibitor of leptin expression, while ALK-1-Smad1/5 as an activator. Indeed, Smad1 expression silencing induced leptin expression inhibition. Furthermore, prednisolone enhanced the expression of TGF-ßRII while decreasing p-Smad2 in BM-MSC and SVF but not in UMSC. In vitro differentiation revealed differential osteogenic potential in SVF, BM-MSC, and UMSC that was correlated to their leptin expression potential. Our results suggest that ALK-1/ALK-5 balance regulates leptin expression in MSC. It also underlines UMSC as leptin nonproducer MSC for cell therapy protocols where leptin expression is not suitable.


Assuntos
Receptores de Activinas Tipo II/metabolismo , Leptina/metabolismo , Células-Tronco Mesenquimais/enzimologia , Proteínas Serina-Treonina Quinases/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Receptores de Activinas Tipo II/genética , Benzamidas/farmacologia , Medula Óssea/metabolismo , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Dioxóis/farmacologia , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Regulação da Expressão Gênica , Inativação Gênica , Humanos , Leptina/antagonistas & inibidores , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Osteogênese , Fosforilação , Prednisolona/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/genética , Receptor do Fator de Crescimento Transformador beta Tipo I , Receptor do Fator de Crescimento Transformador beta Tipo II , Receptores para Leptina/antagonistas & inibidores , Receptores para Leptina/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/antagonistas & inibidores , Receptores de Fatores de Crescimento Transformadores beta/genética , Transdução de Sinais , Proteína Smad2/genética , Proteína Smad2/metabolismo , Fator de Crescimento Transformador beta1/farmacologia , Cordão Umbilical/citologia , Cordão Umbilical/metabolismo
9.
Cell Biol Int ; 34(7): 693-701, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20187873

RESUMO

Many studies have drawn attention to the emerging role of MSC (mesenchymal stem cells) as a promising population supporting new clinical concepts in cellular therapy. However, the sources from which these cells can be isolated are still under discussion. Whereas BM (bone marrow) is presented as the main source of MSC, despite the invasive procedure related to this source, the possibility of isolating sufficient numbers of these cells from UCB (umbilical cord blood) remains controversial. Here, we present the results of experiments aimed at isolating MSC from UCB, BM and UCM (umbilical cord matrix) using different methods of isolation and various culture media that summarize the main procedures and criteria reported in the literature. Whereas isolation of MSC were successful from BM (10:10) and (UCM) (8:8), only one cord blood sample (1:15) gave rise to MSC using various culture media [DMEM (Dulbecco's modified Eagle's medium) +5% platelet lysate, DMEM+10% FBS (fetal bovine serum), DMEM+10% human UCB serum, MSCGM] and different isolation methods [plastic adherence of total MNC (mononuclear cells), CD3+/CD19+/CD14+/CD38+-depleted MNC and CD133+- or LNGFR+-enriched MNC]. MSC from UCM and BM were able to differentiate into adipocytes, osteocytes and hepatocytes. The expansion potential was highest for MSC from UCM. The two cell populations had CD90+/CD73+/CD105+ phenotype with the additional expression of SSEA4 and LNGFR for BM MSC. These results clearly exclude UCB from the list of MSC sources for clinical use and propose instead UCM as a rich, non-invasive and abundant source of MSC.


Assuntos
Sangue Fetal/citologia , Células-Tronco Mesenquimais/citologia , Cordão Umbilical/citologia , Adipócitos/citologia , Adipócitos/imunologia , Animais , Células da Medula Óssea/citologia , Células da Medula Óssea/imunologia , Bovinos , Técnicas de Cultura de Células/métodos , Diferenciação Celular/fisiologia , Separação Celular/métodos , Células Cultivadas , Citometria de Fluxo , Hepatócitos/citologia , Hepatócitos/imunologia , Humanos , Imunofenotipagem , Células-Tronco Mesenquimais/imunologia , Osteócitos/citologia , Osteócitos/imunologia , Fenótipo
10.
Lab Invest ; 89(7): 811-22, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19434061

RESUMO

It was shown recently that synovial fibroblast transformation into adipocytes reduced the expression of interleukin-6 (IL-6) and IL-8. However, the synovial fibroblast adipogenesis was inhibited in inflammatory conditions induced by the tumor necrosis factor-alpha (TNF-alpha). Furthermore, adipogenesis is often accompanied by leptin production, a proinflammatory adipokine in rheumatic diseases. In this study, we tested the phytohormone genistein for adipogenic and anti-inflammatory properties on human synovial fibroblasts. Results showed that genistein was able to transform synovial fibroblasts into adipocytes that expressed perilipin-A and produced adiponectin, but not leptin. Furthermore, genistein enhanced glucocorticoid-mediated synovial fibroblast adipogenesis and, in parallel, downregulated glucocorticoid-induced leptin and leptin receptor. Endogenous and TNF-alpha-induced expressions of IL-6, IL-8, p38, p65 and C/EBP-beta were also downregulated by genistein, showing its anti-inflammatory properties. Peroxisome proliferator- activated receptor-gamma (PPAR-gamma) agonist, rosiglitazone, had a synergic effect on genistein-induced adipogenesis, whereas the non-active tyrosine kinase inhibitor, daidzein, had a significantly inferior adipogenic activity than genistein. The Janus kinase-2 tyrosine kinase inhibitor, AG 490, mimicked the anti-leptin effect of genistein. These results showed that genistein-induced adipogenesis involves PPAR-gamma induction and tyrosine kinase inhibition. In conclusion, genistein, alone or coupled with glucocorticoids, have both adipogenic and anti-inflammatory effects on synovial fibroblasts.


Assuntos
Adipócitos/citologia , Adipócitos/efeitos dos fármacos , Adipogenia/efeitos dos fármacos , Genisteína/farmacologia , Leptina/biossíntese , Membrana Sinovial/citologia , Membrana Sinovial/efeitos dos fármacos , Adipócitos/metabolismo , Anti-Inflamatórios/farmacologia , Sequência de Bases , Diferenciação Celular/efeitos dos fármacos , Primers do DNA/genética , Dexametasona/farmacologia , Regulação para Baixo/efeitos dos fármacos , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Humanos , Técnicas In Vitro , Interleucina-6/biossíntese , Interleucina-8/biossíntese , Interleucina-8/genética , PPAR gama/biossíntese , Fitoestrógenos/farmacologia , Prostaglandina D2/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Rosiglitazona , Transdução de Sinais/efeitos dos fármacos , Membrana Sinovial/metabolismo , Tiazolidinedionas/farmacologia , Fator de Necrose Tumoral alfa/farmacologia
11.
BMC Cancer ; 8: 147, 2008 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-18505570

RESUMO

BACKGROUND: The 21-kDa Vaccinia virus VH1-related (VHR) dual-specific protein phosphatase (encoded by the DUSP3 gene) plays a critical role in cell cycle progression and is itself regulated during the cell cycle. We have previously demonstrated using RNA interference that cells lacking VHR arrest in the G1 and G2 phases of the cell cycle and show signs of beginning of cell senescence. METHODS: In this report, we evaluated successfully the expression levels of VHR protein in 62 hysterectomy or conization specimens showing the various (pre) neoplastic cervical epithelial lesions and 35 additional cases of hysterectomy performed for non-cervical pathologies, from patients under 50 years of age. We used a tissue microarray and IHC technique to evaluate the expression of the VHR phosphatase. Immunofluorescence staining under confocal microscopy, Western blotting and RT-PCR methods were used to investigate the localization and expression levels of VHR. RESULTS: We report that VHR is upregulated in (pre) neoplastic lesions (squamous intraepithelial lesions; SILs) of the uterine cervix mainly in high grade SIL (H-SIL) compared to normal exocervix. In the invasive cancer, VHR is also highly expressed with nuclear localization in the majority of cells compared to normal tissue where VHR is always in the cytoplasm. We also report that this phosphatase is highly expressed in several cervix cancer cell lines such as HeLa, SiHa, CaSki, C33 and HT3 compared to primary keratinocytes. The immunofluorescence technique under confocal microscopy shows that VHR has a cytoplasmic localization in primary keratinocytes, while it localizes in both cytoplasm and nucleus of the cancer cell lines investigated. We report that the up-regulation of this phosphatase is mainly due to its post-translational stabilization in the cancer cell lines compared to primary keratinocytes rather than increases in the transcription of DUSP3 locus. CONCLUSION: These results together suggest that VHR can be considered as a new marker for cancer progression in cervix carcinoma and potential new target for anticancer therapy.


Assuntos
Carcinoma de Células Escamosas/enzimologia , Fosfatase 3 de Especificidade Dupla/biossíntese , Displasia do Colo do Útero/enzimologia , Neoplasias do Colo do Útero/enzimologia , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Linhagem Celular Tumoral , Núcleo Celular/enzimologia , Indução Enzimática , Feminino , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Histerectomia , Queratinócitos/enzimologia , Queratinócitos/patologia , Microscopia Confocal , Análise de Sequência com Séries de Oligonucleotídeos , Estatística como Assunto , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/cirurgia , Displasia do Colo do Útero/patologia , Displasia do Colo do Útero/cirurgia
12.
Retrovirology ; 4: 72, 2007 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-17927817

RESUMO

The CD94/NKG2A heterodimer is a natural killer receptor (NKR), which inhibits cell-mediated cytotoxicity upon interaction with MHC class I gene products. It is expressed by NK cells and by a small fraction of activated CD8+ T lymphocytes. Abnormal upregulation of the CD94/NKG2A inhibitory NKR on cytotoxic T cells (CTLs) could be responsible for a failure of immunosurveillance in cancer or HIV infection. In this study, CD94/NKG2A receptor expression on CD8+ T lymphocytes and NK cells was assessed in 46 HIV-1-infected patients (24 viraemic, 22 aviraemic) and 10 healthy volunteers. The percentage of CD8+ T lymphocytes expressing the CD94/NKG2A inhibitory heterodimer was very significantly decreased in HIV-1-infected patients in comparison with non-infected controls. Within the HIV infected patients, the proportion of CD8+ T lymphocytes and NK cells expressing CD94/NKG2A was higher in subjects with undetectable viral loads in comparison with their viraemic counterparts. No significant difference was detected in the proportion of CD8+ T lymphocytes expressing the activatory CD94/NKG2C heterodimer between the HIV-1 infected patients and the healthy donors, nor between the vireamic and avireamic HIV-1 infected patients. In conclusion, chronic stimulation with HIV antigens in viraemic patients leads to a decreased rather than increased CD94/NKG2A expression on CD8+ T lymphocytes and NK cells.


Assuntos
Linfócitos T CD8-Positivos/metabolismo , Infecções por HIV/imunologia , HIV-1 , Subfamília D de Receptores Semelhantes a Lectina de Células NK/metabolismo , Receptores Imunológicos/metabolismo , Doença Crônica , Regulação para Baixo , Infecções por HIV/virologia , Humanos , Células Matadoras Naturais/metabolismo , Subfamília C de Receptores Semelhantes a Lectina de Células NK , Receptores de Células Matadoras Naturais , Carga Viral
13.
Biochem Pharmacol ; 70(5): 714-24, 2005 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-15978547

RESUMO

The CD94/NKG2A heterodimer is a natural killer receptor (NKR), which inhibits cell-mediated cytotoxicity upon interaction with MHC class I gene products. It is expressed by NK cells and by a small fraction of activated T cells, predominantly of CD8+ phenotype. Abnormal upregulation of the CD94/NKG2A inhibitory NKR on cytotoxic T cells (CTLs) could be responsible for a failure of immunosurveillance in cancer or HIV infection. In an attempt to identify the mechanisms leading to inhibitory NKR upregulation on T cells, we analyzed the expression of the CD94/NKG2A heterodimer on human CTLs activated with anti-CD3 mAb in the presence of PGE2 or with 8-CPT-cAMP, an analogue of cyclic AMP. As previously described, anti-CD3 mAb-mediated activation induced the expression of CD94/NKG2A on a small fraction of CD8+ T cells. Interestingly, when low concentrations of PGE2 or 8-CPT-cAMP were present during the culture, the proportion of CD8+ T cells expressing CD94/NKG2A was two- to five-fold higher. This upregulation was partially prevented by PKA inhibitors, such as KT5720 and Rp-8-Br-cAMP (type I selective). We also report that cAMP induces upregulation of NKG2A at the mRNA level. We further demonstrated that cross-linking of CD94 on CD8+ T cells expressing the CD94/NKG2A heterodimer inhibits their cytotoxic activity in a bispecific antibody redirected lysis assay. Our findings clearly demonstrate that the PGE2/cAMP/PKA type I axis is involved in the expression of CD94/NKG2A receptor on human CD8+ T lymphocytes.


Assuntos
Antígenos CD/biossíntese , Linfócitos T CD8-Positivos/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/fisiologia , Dinoprostona/farmacologia , Lectinas Tipo C/biossíntese , Receptores Imunológicos/biossíntese , Antígenos CD/genética , Antígenos CD/fisiologia , AMP Cíclico/análogos & derivados , AMP Cíclico/farmacologia , AMP Cíclico/fisiologia , Humanos , Lectinas Tipo C/genética , Lectinas Tipo C/fisiologia , Subfamília C de Receptores Semelhantes a Lectina de Células NK , Subfamília D de Receptores Semelhantes a Lectina de Células NK , RNA Mensageiro/análise , Receptores Imunológicos/genética , Receptores Imunológicos/fisiologia , Receptores de Células Matadoras Naturais , Tionucleotídeos/farmacologia
14.
Biochem J ; 384(Pt 3): 469-76, 2004 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-15344910

RESUMO

MAIDS (murine AIDS) is caused by infection with the murine leukaemia retrovirus RadLV-Rs and is characterized by a severe immunodeficiency and T-cell anergy combined with a lymphoproliferative disease affecting both B- and T-cells. Hyperactivation of the cAMP-protein kinase A pathway is involved in the T-cell dysfunction of MAIDS and HIV by inhibiting T-cell activation through the T-cell receptor. In the present study, we show that MAIDS involves a strong and selective up-regulation of cyclo-oxygenase type 2 in the CD11b+ subpopulation of T- and B-cells of the lymph nodes, leading to increased levels of PGE2 (prostaglandin E2). PGE2 activates the cAMP pathway through G-protein-coupled receptors. Treatment with cyclo-oxygenase type 2 inhibitors reduces the level of PGE2 and thereby reverses the T-cell anergy, restores the T-cell immune function and ameliorates the lymphoproliferative disease.


Assuntos
Dinoprostona/metabolismo , Prostaglandina-Endoperóxido Sintases/metabolismo , Vírus da Leucemia Induzida por Radiação/fisiologia , Linfócitos T/patologia , Linfócitos T/virologia , Animais , Linfócitos B/metabolismo , Linfócitos B/virologia , Antígeno CD11b/análise , Antígeno CD11b/metabolismo , Anergia Clonal , AMP Cíclico/metabolismo , Ciclo-Oxigenase 1 , Ciclo-Oxigenase 2 , Inibidores de Ciclo-Oxigenase 2 , Inibidores de Ciclo-Oxigenase/farmacologia , Dinoprostona/antagonistas & inibidores , Dinoprostona/biossíntese , Indução Enzimática , HIV/imunologia , HIV/patogenicidade , Linfonodos/citologia , Linfonodos/enzimologia , Linfonodos/imunologia , Linfonodos/virologia , Ativação Linfocitária , Masculino , Proteínas de Membrana , Camundongos , Camundongos Endogâmicos C57BL , Síndrome de Imunodeficiência Adquirida Murina/imunologia , Síndrome de Imunodeficiência Adquirida Murina/metabolismo , Síndrome de Imunodeficiência Adquirida Murina/patologia , Síndrome de Imunodeficiência Adquirida Murina/virologia , Vírus da Leucemia Induzida por Radiação/patogenicidade , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais , Linfócitos T/imunologia , Linfócitos T/metabolismo
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