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1.
MicroPubl Biol ; 20222022.
Artigo em Inglês | MEDLINE | ID: mdl-35098048

RESUMO

While evaluating the effect on lifespan of decreased ribosomal protein (Rp) expression in Drosophila, we discovered a potential function in the same process for the Molybdenum cofactor synthesis 1 (Mocs1) gene. We utilized the UAS-GAL4 inducible system, by crossing tissue-specific GAL4 drivers to the Harvard Drosophila Transgenic RNAi Project (TrIP) responder lines for Rp gene knockdown. We also employed a negative control that knocked down a gene unrelated to Drosophila (GAL4). Relative to the genetic background in which no driven transgenes were present, lifespan was significantly lengthened in females, both for Rp knockdown and the negative GAL4 control. We reasoned that the Mocs1 gene, located immediately downstream of the integration site on the third chromosome where all the TrIP responders are targeted might be responsible for the lifespan effects observed, due to the potential for upregulation using the UAS-GAL4 system. We repeated the lifespan experiment using an enhancer trap in the same location as the TrIP transgenes, and found that lifespan was significantly lengthened in females that possessed both the driver and responder, relative to controls, implicating Mocs1 in the biology of aging.

2.
Arch Gynecol Obstet ; 299(1): 203-209, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30306311

RESUMO

PURPOSE: Cervical cancer is one of the most frequent cancers in women worldwide. In most of all cases, a persistent HPV infection is the leading cause. HPV-specific sequences are able to bind glucocorticoid receptor (GR). Dexamethasone can increase the activity of early promoters in HPV16 and HPV18 interfering in transcription control of viral oncogenes. The aim of our study was to evaluate glucocorticoid receptor as transcriptional factor in its active form in the nucleus of in cervical cancer cells and to correlate the results with clinical patient specific parameters. METHODS: A total of 250 paraffin-embedded cervical cancer samples obtained from patients having undergone surgery for cervical cancer were used for the study. The expression of GR was immunhistochemical examined and evaluated by a semi-quantitative scoring. SPSS software was used for the statistical evaluation of staining results and survival analysis of patients with cervical cancer. RESULTS: GR is frequently expressed in cervical carcinoma tissue in favor of squamous cell carcinoma (SCC). An enhanced expression is correlated with rather small clinical stages. The expression of the GR is correlated with better overall survival and progression-free survival. CONCLUSIONS: The glucocorticoid receptor is frequently expressed in cervical carcinoma tissue in favor of squamous cell carcinoma. An enhanced expression is correlated with rather small clinical stages. The expression of the analyzed receptor is correlated with better overall survival. Further studies are needed to determine useful treatment targets for glucocorticoid receptor manipulation.


Assuntos
Carcinoma de Células Escamosas/patologia , Receptores de Glucocorticoides/metabolismo , Displasia do Colo do Útero/patologia , Neoplasias do Colo do Útero/patologia , Adulto , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/virologia , Feminino , Papillomavirus Humano 16/genética , Humanos , Pessoa de Meia-Idade , Infecções por Papillomavirus/patologia , Infecções por Papillomavirus/virologia , Inclusão em Parafina/métodos , Regiões Promotoras Genéticas , Análise de Sobrevida , Transcrição Gênica , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/virologia , Displasia do Colo do Útero/metabolismo , Displasia do Colo do Útero/virologia
3.
Oncol Lett ; 14(4): 4467-4476, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29085443

RESUMO

High-risk human papilloma virus (HPV) is the leading cause of cervical cancer. HPV oncogenes are responsible for the development of malignancy, and the E6 oncoprotein that HPV expresses induces the degradation of tumour suppressor protein p53 (p53). This degradation leads to the upregulation of p16; however, unidentified proteins may also serve a role in the development and progression of cervical cancer. Therefore, the aim of the present study was to analyse the expression levels of E6, p53, p16, MDM2 proto-oncogene (MDM2) and galectin-3 (gal-3) in cervical cancer specimens. A total of 250 cervical cancer tissue slides were used. The expression of E6, p53, p16, MDM2 and gal-3 was analysed with immunohistochemical methods and a semi-quantitative scoring. SPSS software was used for the statistical evaluation of staining results and survival analysis of patients with cervical cancer. Cervical cancer specimens demonstrated significantly increased E6 staining with advanced T-status and increased International Federation of Gynecology and Obstetrics classification. E6, p53 and p16 demonstrated significantly different expression levels in squamous epithelial tissue compared with adenocarcinomas. MDM2 and gal-3 demonstrated positively correlated expression levels in cervical cancer. In addition, gal-3 expression was correlated with poor prognosis in p16-negative cases. A negative correlation between the expression of E6 and a mutated form of p53 was also identified in cervical cancer. p53 mutation was demonstrated to be common in cervical cancer, and gal-3 and MDM2 appeared to act in a combined manner in this type of tumour. As gal-3 is overexpressed in the cervical cancer tissue of patients with poor prognosis, the use of gal-3 inhibitors should be investigated in future studies.

4.
Anal Chem ; 89(11): 6175-6181, 2017 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-28489359

RESUMO

In this work, we present the combination of microfluidic chips and mass spectrometry employing laser-induced liquid beam ionization/desorption. The developed system was evaluated with respect to stable beam generation and laser parameters as well as solvent compatibility. The device was exemplarily applied to study a vinylogous Mannich reaction performed in continuous flow on chip. Fast processes can be observed with this technique which in the future could be beneficial for studying intermediates or contribute to the elucidation of reaction mechanisms.

5.
Int J Mol Sci ; 18(3)2017 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-28241481

RESUMO

Chromatin remodeling alters gene expression in carcinoma tissue. Although cervical cancer is the fourth most common cancer in women worldwide, a systematic study about the prognostic value of specific changes in the chromatin structure, such as histone acetylation or histone methylation, is missing. In this study, the expression of histone H3 acetyl K9, which is known to denote active regions at enhancers and promoters, and histone H3 tri methyl K4, which preferentially identifies active gene promoters, were examined as both show high metastatic potential. A panel of patients with cervical cancer was selected and the importance of the histone modifications concerning survival-time (overall survival and relapse-free survival) was analyzed in 250 cases. Histone H3 acetyl K9 staining was correlated with low grading, low FIGO (TNM classification and the International Federation of Gynecology and Obstetrics) status, negative N-status and low T-status in cervical cancer, showing a higher expression in adenocarcinoma than in squamous cell carcinoma. Cytoplasmic expression of histone H3 tri methyl K4 in a cervical cancer specimen was correlated with advanced T-status and poor prognosis. While cytoplasmic H3K4me3 expression seemed to be a marker of relapse-free survival, nuclear expression showed a correlation to poor prognosis in overall survival. Within this study, we analyzed the chemical modification of two histone proteins that are connected to active gene expression. Histone H3 acetyl K9 was found to be an independent marker of overall survival. Histone H3 tri methyl K4 was correlated with poor prognosis and it was found to be an independent marker of relapse-free survival. Therefore, we could show that chromatin remodeling plays an important role in cervical cancer biology.


Assuntos
Biomarcadores Tumorais/metabolismo , Histonas/metabolismo , Processamento de Proteína Pós-Traducional , Neoplasias do Colo do Útero/metabolismo , Acetilação , Adulto , Idoso , Idoso de 80 Anos ou mais , Montagem e Desmontagem da Cromatina , Feminino , Humanos , Metilação , Pessoa de Meia-Idade , Prognóstico , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/patologia
6.
BMC Cancer ; 16(1): 870, 2016 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-27825375

RESUMO

BACKGROUND: Galectin-1 (gal-1) belongs to the family of ß-galactoside-binding proteins which primarily recognizes the Galß1-4GlcNAc sequences of oligosaccharides associated with several cell surface glycoconjugates. The lectin recognizes correspondent glycoepitopes on human breast cancer cells. Galectin-1 is expressed both in normal and malignant tissues. Lymphatic organs naturally possessing high rates of apoptotic cells, express high levels of Galectin-1. Furthermore galectin-1 can initiate T cell apoptosis. Binding of galectin-1 to trophoblast tumor cells presenting the oncofetal Thomsen-Friedenreich (TF) carbohydrate antigen inhibits tumor cell proliferation. In this study we examined the impact galectin-1 has in vitro on cell proliferation, apoptotic potential and metabolic activity of MCF-7 and T-47D breast cancer cells in dependence to their expression of the Thomsen-Friedenreich (TF) tumor antigen. METHODS: For proliferation and apoptosis assays cells were grown in presence of 10, 30 and 60 µg gal-1/ml medium. Cell proliferation was determined by a BrdU uptake ELISA. Detection of apoptotic cells was done by M30 cyto death staining, in situ nick translation and by a nucleosome ELISA method. Furthermore we studied the impact galectin-1 has on the metabolic activity of MCF-7 and T-47D cells in a homotypic three-dimensional spheroid cell culture model mimicking a micro tumour environment. RESULTS: Gal-1 inhibited proliferation of MCF-7 cells (strong expression of the TF epitope) but did not significantly change proliferation of T-47D cells (weak expression of the TF epitope). The incubation of MCF-7 cells with gal-1 raised number of apoptotic cells significantly. Treating the spheroids with 30 µg/ml galectin-1 in addition to standard chemotherapeutic regimes (FEC, TAC) resulted in further suppression of the metabolic activity in MCF-7 cells whereas T-47D cells were not affected. CONCLUSIONS: Our results demonstrate that galectin-1 can inhibit proliferation und metabolic cell activity and induce apoptosis in breast tumor cell lines with high expression levels of the Thomsen-Friedenreich (TF) antigen in monolayer and spheroid cell culture models.


Assuntos
Apoptose , Galectina 1/metabolismo , Antígenos Glicosídicos Associados a Tumores/metabolismo , Apoptose/genética , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Galectina 1/genética , Expressão Gênica , Humanos , Imuno-Histoquímica , Células MCF-7 , Ligação Proteica , Esferoides Celulares , Células Tumorais Cultivadas
7.
Nutrients ; 8(10)2016 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-27740591

RESUMO

Hereinwe investigated the effect of elderflower extracts (EFE) and of enterolactone/enterodiol on hormone production and proliferation of trophoblast tumor cell lines JEG-3 and BeWo, as well as MCF7 breast cancer cells. The EFE was analyzed by mass spectrometry. Cells were incubated with various concentrations of EFE. Untreated cells served as controls. Supernatants were tested for estradiol production with an ELISA method. Furthermore, the effect of the EFE on ER/ER/PR expression was assessed by immunocytochemistry. EFE contains a substantial amount of lignans. Estradiol production was inhibited in all cells in a concentration-dependent manner. EFE upregulated ER in JEG-3 cell lines. In MCF7 cells, a significant ER downregulation and PR upregulation were observed. The control substances enterolactone and enterodiol in contrast inhibited the expression of both ER and of PR in MCF7 cells. In addition, the production of estradiol was upregulated in BeWo and MCF7 cells in a concentration dependent manner. The downregulating effect of EFE on ER expression and the upregulation of the PR expression in MFC-7 cells are promising results. Therefore, additional unknown substances might be responsible for ER downregulation and PR upregulation. These findings suggest potential use of EFE in breast cancer prevention and/or treatment and warrant further investigation.


Assuntos
Estradiol/metabolismo , Fitoestrógenos/farmacologia , Extratos Vegetais/farmacologia , Sambucus/química , Neoplasias Trofoblásticas/tratamento farmacológico , 4-Butirolactona/análogos & derivados , 4-Butirolactona/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imuno-Histoquímica , Lignanas/farmacologia , Células MCF-7/metabolismo , Gravidez , Progesterona/metabolismo , Receptores de Estrogênio/efeitos dos fármacos , Neoplasias Trofoblásticas/metabolismo , Neoplasias Uterinas/química , Neoplasias Uterinas/tratamento farmacológico
8.
Proc Natl Acad Sci U S A ; 113(38): 10714-9, 2016 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-27601658

RESUMO

Galactolipids [monogalactosyldiacylglycerol (MGDG) and digalactosyldiacylglycerol (DGDG)] are the hallmark lipids of photosynthetic membranes. The galactolipid synthases MGD1 and DGD1 catalyze consecutive galactosyltransfer reactions but localize to the inner and outer chloroplast envelopes, respectively, necessitating intermembrane lipid transfer. Here we show that the N-terminal sequence of DGD1 (NDGD1) is required for galactolipid transfer between the envelopes. Different diglycosyllipid synthases (DGD1, DGD2, and Chloroflexus glucosyltransferase) were introduced into the dgd1-1 mutant of Arabidopsis in fusion with N-terminal extensions (NDGD1 and NDGD2) targeting to the outer envelope. Reconstruction of DGDG synthesis in the outer envelope membrane was observed only with diglycosyllipid synthase fusion proteins carrying NDGD1, indicating that NDGD1 enables galactolipid translocation between envelopes. NDGD1 binds to phosphatidic acid (PA) in membranes and mediates PA-dependent membrane fusion in vitro. These findings provide a mechanism for the sorting and selective channeling of lipid precursors between the galactolipid pools of the two envelope membranes.


Assuntos
Proteínas de Arabidopsis/genética , Membrana Celular/genética , Galactolipídeos/biossíntese , Galactolipídeos/genética , Galactosiltransferases/genética , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Membrana Celular/metabolismo , Cloroplastos/genética , Cloroplastos/metabolismo , Galactolipídeos/metabolismo , Galactosiltransferases/metabolismo , Regulação da Expressão Gênica de Plantas , Lipídeos de Membrana/genética , Lipídeos de Membrana/metabolismo , Fotossíntese/genética , Transporte Proteico/genética
9.
Nutr Cancer ; 65(5): 739-45, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23859042

RESUMO

Phytoestrogens have a controversial effect on hormone-dependent tumours. Herein, we investigated the effect of the pumpkin seed extract (PSE) on estradiol production and estrogen receptor (ER)-α/ER-ß/progesterone receptor (PR) status on MCF7, Jeg3, and BeWo cells. The PSE was prepared and analyzed by mass spectrometry. MCF7, Jeg3, and BeWo cells were incubated with various concentrations of PSE. Untreated cells served as controls. Supernatants were tested for estradiol production with an ELISA method. Furthermore, the effect of the PSE on ER-α/ER-ß/PR expression was assessed by immunocytochemistry. The PSE was found to contain both lignans and flavones. Estradiol production was elevated in MCF7, BeWo, and Jeg3 cells in a concentration-dependent manner. In MCF7 cells, a significant ER-α downregulation and a significant PR upregulation were observed. The above results after properly designed animal studies could highlight a potential role of pumpkin seed's lignans in breast cancer prevention and/or treatment.


Assuntos
Estradiol/metabolismo , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/metabolismo , Fitoestrógenos/farmacologia , Extratos Vegetais/farmacologia , Receptores de Progesterona/metabolismo , Neoplasias da Mama , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cucurbita/química , Regulação para Baixo , Receptor alfa de Estrogênio/genética , Receptor beta de Estrogênio/genética , Feminino , Flavonas/farmacologia , Humanos , Imuno-Histoquímica , Lignanas/farmacologia , Células MCF-7 , Receptores de Progesterona/genética , Sementes/química , Neoplasias Trofoblásticas , Regulação para Cima
10.
J Control Release ; 162(2): 295-302, 2012 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-22820452

RESUMO

The pathways of interferon α2a release from a triglyceride based implant system were studied by single molecule fluorescence microscopy. The protein was labeled with a stable fluorescent dye ATTO647N, freeze-dried and embedded into the lipid matrix via twin-screw extrusion. The implant system consisted of a pore-forming agent (water soluble PEG 6000) and two types of triglycerides with different melting ranges which allowed the production of the implants at moderate temperatures and without the use of organic solvents. Single molecule microscopy and single particle tracking of labeled proteins contained in these implants revealed that two populations of diffusing proteins were present. Moreover, proteins were not only released via water-filled pores (created by dissolution of the pore-former), but surprisingly also through diffusion in a phase of molten lipid. Diffusion coefficients of IFNα 2a derived by tracking of individual protein molecules within the implant system were similar to diffusion coefficients obtained from control measurements in pure molten lipid and highly concentrated solutions of PEG 6000. In conclusion, tracking of individual protein molecules was successfully used to elucidate the release pathways of proteins from a relevant lipid based implant system.


Assuntos
Implantes de Medicamento/química , Interferon-alfa/química , Triglicerídeos/química , Composição de Medicamentos , Corantes Fluorescentes/química , Interferon alfa-2 , Microscopia de Fluorescência , Proteínas Recombinantes/química
11.
J Perinat Med ; 40(4): 373-8, 2012 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-22752767

RESUMO

α-Tocopherol transfer protein (α-TTP) has been identified as the major intracellular transport protein for the antioxidant vitamin E (α-tocopherol). Expression of α-TTP on the reproductive system has been described both in mouse uterus and lately in the human placenta. The aim of this study was to clarify if placental expression of α-TTP can be modified by substances causing oxidative reactions. The human choriocarcinoma cell line BeWo was, therefore, treated with two known pro-oxidants. α-TTP expression was determined with immunocytochemistry and evaluated by applying a semiquantitative score. The presence of pro-oxidants in BeWo cells induced α-TTP expression. We thus hypothesize that stimulation of α-TTP expression by oxidative stress, as this was induced by pro-oxidants, could be part of an antioxidant process occurring in the placenta in the aim of enhancing the supply of α-tocopherol. This process could occur both in normal pregnancies, as well as in pregnancy disorders presented with intensified oxidative stress. In that view, this model is proposed for further oxidative stress studies on trophoblast and placenta, on the grounds of clarifying the role of α-tocopherol in pregnancy physiology and pathophysiology.


Assuntos
Proteínas de Transporte/análise , Coriocarcinoma/metabolismo , Estresse Oxidativo/fisiologia , Antioxidantes , Linhagem Celular Tumoral , Feminino , Humanos , Imuno-Histoquímica , Oxidantes/farmacologia , Gravidez , Neoplasias Uterinas/metabolismo , Vitamina E/fisiologia , alfa-Tocoferol/metabolismo
12.
G3 (Bethesda) ; 2(6): 629-42, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22690372

RESUMO

Many proteins require the addition of a hydrophobic prenyl anchor (prenylation) for proper trafficking and localization in the cell. Prenyl proteases play critical roles in modifying proteins for membrane anchorage. The type I prenyl protease has a defined function in yeast (Ste24p/Afc1p) where it modifies a mating pheromone, and in humans (Zmpste24) where it has been implicated in a disease of premature aging. Despite these apparently very different biological processes, the type I prenyl protease gene is highly conserved, encoded by a single gene in a wide range of animal and plant groups. A notable exception is Drosophila melanogaster, where the gene encoding the type I prenyl protease has undergone an unprecedented series of duplications in the genome, resulting in five distinct paralogs, three of which are organized in a tandem array, and demonstrate high conservation, particularly in the vicinity of the active site of the enzyme. We have undertaken targeted deletion to remove the three tandem paralogs from the genome. The result is a male fertility defect, manifesting late in spermatogenesis. Our results also show that the ancestral type I prenyl protease gene in Drosophila is under strong purifying selection, while the more recent replicates are evolving rapidly. Our rescue data support a role for the rapidly evolving tandem paralogs in the male germline. We propose that potential targets for the male-specific type I prenyl proteases include proteins involved in the very dramatic cytoskeletal remodeling events required for spermatid maturation.

13.
Anticancer Res ; 32(5): 2023-9, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22593483

RESUMO

AIM: Tumour markers hold a great relevance in the diagnosis and the follow-up treatment of different kinds of human carcinoma. Although head and neck cancer occurs frequently, there is still lack of appropriate tumour markers. Our investigation on the expression of sialyl Lewis A (CA19-9) in laryngeal carcinomas, consists of systematical analysis of oncofetal carbohydrates and of galectins 1 and 3 in different normal and malignant tissues of the aerodigestive tract. MATERIALS AND METHODS: Paraffin-embedded sections of normal tongue, vocal cord, larynx, pharynx and epiglottis, representing normal control tissue and laryngeal cancer tissue were incubated with monoclonal antibodies against sialyl Lewis A and X (sLeA and X), Lewis Y (LeY), the Thomsen-Friedenreich (TF) antigen and galectin 1 and 3 (Gal-1 and -3). A staining reaction was carried out with ABC-peroxidase and diaminobenzidine (DAB). Tissue of breast cancer was used as a positive control. Mouse IgM, as isotype control antibody, was used as a negative control. Semi quantitative evaluation was carried out double-blinded, by two independent investigators, including a pathologist. RESULTS: Squamous epithelia of all investigated normal tissues of the aerodigestive tract show nearly the same pattern. Most impressive findings are the very weak expression of Gal-1 and the total absence of the TF antigen. Laryngeal cancer reveals high amounts of sLeA, Gal-1 and the TF antigen. CONCLUSION: On the basis of our findings in normal tissue of the aeradigestive tract, these three markers qualified as potential tumour markers for carcinoma of the aerodigestive tract. In particular, the high expression of TF in cancer tissue and its absence from the normal tissue is promising for its establishment as a new tumour marker in this field.


Assuntos
Antígenos Glicosídicos Associados a Tumores/análise , Biomarcadores Tumorais/análise , Galectina 1/análise , Galectina 3/análise , Trato Gastrointestinal/química , Neoplasias Laríngeas/química , Faringe/química , Língua/química , Humanos , Imuno-Histoquímica
14.
Int J Pharm ; 421(1): 120-9, 2011 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-21983095

RESUMO

Highly concentrated antibody solutions are of increasing importance in the pharmaceutical industry. During production highly concentrated solutions are usually prepared by tangential flow filtration (TFF). Since this technique is often not applicable in the early phase of formulation development, where the available amounts of protein are commonly very small, small scale techniques like dialysis or ultrafiltration with stirred cells or centrifugal filters have to be employed. In this study the small scale techniques were compared to tangential flow filtration, with regard to the quality and stability of the concentrated products. The achievable concentration of a protein, when starting from a model antibody solution with 10mg/ml, was also assessed. Concentrations above 100mg/ml could be obtained with all techniques, however with different product qualities. The stability of the highly concentrated solutions (100 mg/ml) was analyzed by turbidity measurements, size exclusion chromatography (SEC), SDS-PAGE and isoelectric focusing (IEF) after storage at 25 and 40°C for 8 weeks. Solutions prepared by dialysis exhibited the smallest degree of instability, whereas those manufactured by centrifugal filtration revealed the best comparability to products obtained by tangential flow filtration with regard to the results of isoelectric focusing, turbidity measurements (UV-vis) and size exclusion chromatography. Stability differences were observed within all analytical methods, primarily after storage and not directly after the concentration process.


Assuntos
Anticorpos Monoclonais/química , Imunoglobulina G/química , Anticorpos Monoclonais/análise , Celulose , Química Farmacêutica , Diálise , Estabilidade de Medicamentos , Eletroforese em Gel de Poliacrilamida , Imunoglobulina G/análise , Focalização Isoelétrica , Membranas Artificiais , Nefelometria e Turbidimetria , Polímeros , Sulfonas , Ultrafiltração
15.
Mol Hum Reprod ; 17(12): 747-57, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21831883

RESUMO

Galectin-1 (gal-1), a member of the mammalian ß-galactoside-binding proteins, exerts biological effects by recognition of glycan ligands, including those involved in cell adhesion and growth regulation. In a previous study, we demonstrated that gal-1 induces cell differentiation processes on the membrane of choriocarcinoma cells BeWo, including the receptor tyrosine kinases, REarranged during transfection, janus kinase 2 and vascular endothelial growth factor receptor 3. Within this study, we examined which mitogen-activated protein kinases (MAPK) and serine/threonine kinases were phoshorylated by gal-1. Out of a number of 21 different MAPKs and other serine/threonine kinases, the stimulation of BeWo cells with gal-1 showed a significant alteration of signal intensity in extracellular-regulated kinases 1/2 (ERK1/2), Akt-3, Akt-pan and glycogen synthase kinase-α/ß (GSK-3α/ß). We demonstrated that gal-1 significantly inhibited ERK1/2, Akt-3/pan and GSK-3α/ß phosphorylation in BeWo cells and in addition induced Elk1 transcription factor activation. In contrast to gal-1 effects, MAPK inhibitor U0126 reduced syncytium formation of BeWo cells. The results of our data showed that phosphorylation of MAP kinases are involved in gal-1-induced signal transduction processes in BeWo cells. Additional results obtained with MAPK inhibitor U0126 close the gap between syncytium formation induced by gal-1 and MAPK activation in trophoblast cells. Furthermore, we demonstrated that gal-1 induces the activation of Elk1, a transcription factor that is activated by MAPK pathways.


Assuntos
Coriocarcinoma/metabolismo , Galectina 1 , Regulação Neoplásica da Expressão Gênica , Células Gigantes/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Trofoblastos/efeitos dos fármacos , Neoplasias Uterinas/metabolismo , Butadienos/farmacologia , Diferenciação Celular/efeitos dos fármacos , Fusão Celular , Coriocarcinoma/genética , Coriocarcinoma/patologia , Inibidores Enzimáticos/farmacologia , Feminino , Galectina 1/metabolismo , Galectina 1/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células Gigantes/citologia , Células Gigantes/metabolismo , Quinase 3 da Glicogênio Sintase/antagonistas & inibidores , Quinase 3 da Glicogênio Sintase/genética , Quinase 3 da Glicogênio Sintase/metabolismo , Humanos , Janus Quinase 2/genética , Janus Quinase 2/metabolismo , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Nitrilas/farmacologia , Fosforilação/efeitos dos fármacos , Gravidez , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/genética , Trofoblastos/citologia , Trofoblastos/metabolismo , Células Tumorais Cultivadas , Neoplasias Uterinas/genética , Neoplasias Uterinas/patologia , Proteínas Elk-1 do Domínio ets/agonistas , Proteínas Elk-1 do Domínio ets/genética , Proteínas Elk-1 do Domínio ets/metabolismo
16.
Anticancer Res ; 30(5): 1849-53, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20592391

RESUMO

BACKGROUND: The clinical relevance of the carbohydrate antigen Sialyl Lewis a (SLea) as a serum tumor marker in diagnosis and follow-up treatment is unquestioned in a broad spectra of human carcinomas. Overexpression of this antigen is combined with poor prognosis and malignant relapse. The aim of our study was the systematic investigation of SLea expression in squamous cell carcinoma of the larynx versus normal and phlogistic tissue. MATERIALS AND METHODS: Paraffin-embedded sections of normal, phlogistic and squamous cell carcinoma tissue were incubated with a monoclonal antibody against SLea. The staining reaction was performed using ABC-Peroxidase and DAB. As a positive control tissue of breast cancer was used and the negative control was performed with unspecific mouse IgM. Semiquantitative evaluations were carried out double-blinded by two independent investigators, including a pathologist. RESULTS: A very faint expression of SLea (Ca19-9) in normal laryngeal tissue, a moderate upregulation in phlogistic tissue and a dramatic upregulation in some types of squamous cell carcinoma of the larynx were observed. Laryngeal cancer is the most common cancer of the upper aerodigestive tract. Most cases of laryngeal cancer are squamous cell carcinoma and can be classified into: well differentiated (more than 75% keratinization), moderately differentiated (25-75% keratinization), and poorly differentiated (<25% keratinisation) carcinomas. CONCLUSION: The results of this study indicate that SLea is a potential tumor marker in carcinoma of the larynx.


Assuntos
Biomarcadores Tumorais/biossíntese , Antígeno CA-19-9/biossíntese , Carcinoma de Células Escamosas/sangue , Regulação Neoplásica da Expressão Gênica , Neoplasias Laríngeas/sangue , Antígenos CD15/biossíntese , Carboidratos/química , Humanos , Imuno-Histoquímica/métodos , Queratinas/química , Antígeno Sialil Lewis X , Regulação para Cima
17.
PLoS One ; 4(10): e7564, 2009 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-19855837

RESUMO

Nuclear intermediate filament proteins, called lamins, form a meshwork that lines the inner surface of the nuclear envelope. Lamins contain three domains: an N-terminal head, a central rod and a C-terminal tail domain possessing an Ig-fold structural motif. Lamins are classified as either A- or B-type based on structure and expression pattern. The Drosophila genome possesses two genes encoding lamins, Lamin C and lamin Dm(0), which have been designated A- and B-type, respectively, based on their expression profile and structural features. In humans, mutations in the gene encoding A-type lamins are associated with a spectrum of predominantly tissue-specific diseases known as laminopathies. Linking the disease phenotypes to cellular functions of lamins has been a major challenge. Drosophila is being used as a model system to identify the roles of lamins in development. Towards this end, we performed a comparative study of Drosophila and human A-type lamins. Analysis of transgenic flies showed that human lamins localize predictably within the Drosophila nucleus. Consistent with this finding, yeast two-hybrid data demonstrated conservation of partner-protein interactions. Drosophila lacking A-type lamin show nuclear envelope defects similar to those observed with human laminopathies. Expression of mutant forms of the A-type Drosophila lamin modeled after human disease-causing amino acid substitutions revealed an essential role for the N-terminal head and the Ig-fold in larval muscle tissue. This tissue-restricted sensitivity suggests a conserved role for lamins in muscle biology. In conclusion, we show that (1) localization of A-type lamins and protein-partner interactions are conserved between Drosophila and humans, (2) loss of the Drosophila A-type lamin causes nuclear defects and (3) muscle tissue is sensitive to the expression of mutant forms of A-type lamin modeled after those causing disease in humans. These studies provide new insights on the role of lamins in nuclear biology and support Drosophila as a model for studies of human laminopathies involving muscle dysfunction.


Assuntos
Lamina Tipo A/química , Lamina Tipo A/genética , Animais , Animais Geneticamente Modificados , Núcleo Celular/metabolismo , Drosophila melanogaster , Regulação da Expressão Gênica , Humanos , Lamina Tipo A/biossíntese , Lamina Tipo A/metabolismo , Músculos/patologia , Mutação , Membrana Nuclear/metabolismo , Distribuição Tecidual , Técnicas do Sistema de Duplo-Híbrido
18.
J Control Release ; 140(1): 27-33, 2009 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-19619592

RESUMO

The question whether lipid based - especially triglyceride based - depot systems can undergo biodegradation is despite many in vivo studies still unanswered. In this paper we studied biodegradation processes in vitro by incubating these lipid based systems in buffer media containing lipases. The main degradation product the free fatty acids (FFA) were isolated from the drawn samples and after derivatization analyzed with RP-HPLC. Lipid microparticles showed a rapid biodegradation whereas the complete degradation of compressed implants would take several months or years. For these two systems surface degradation can be stated. Surprisingly lipid based extrudates changed their structure dramatically upon lipase incubation resulting in a breakdown of the lipid matrix and formation of small lipid particles in the microm-range. This sort of bulk-degradation may enable the use of lipid based extrudates for the long term delivery of drugs. However additional in vivo experiments will be necessary to fully characterize these degradation processes.


Assuntos
Portadores de Fármacos/metabolismo , Sistemas de Liberação de Medicamentos , Lipase/metabolismo , Metabolismo dos Lipídeos , Lipídeos/química , Animais , Soluções Tampão , Química Farmacêutica , Besouros/enzimologia , Concentração de Íons de Hidrogênio , Nanopartículas/química , Nanopartículas/ultraestrutura , Tamanho da Partícula , Fosfatos/química , Pseudomonas/enzimologia , Tecnologia Farmacêutica , Temperatura , Triglicerídeos/metabolismo
19.
J Histochem Cytochem ; 57(9): 871-81, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19506091

RESUMO

Mucin 1 (MUC1) is a glycoprotein in human endometrium and is abundant at the luminal epithelial surface in the receptive phase. It has a highly glycosylated ecto-domain that contains keratan sulfate chains, that disappears at the time of implantation. In addition, the glycoforms on MUC1 differ in fertile and infertile women. Therefore the aims of this study were investigations on glycosylation of MUC1 with the Thomsen-Friedenreich (TF) epitope on normal human endometrium throughout the menstrual cycle and binding of galectin-1 on the TF epitope in the endometrium and the expression of galectin-1 on the human oocyte. Human endometrial tissue was obtained from 54 premenopausal patients and was immunohistochemically analyzed with monoclonal antibodies against MUC1, TF epitope, galectin-1, and biotinylated galectin-1. In addition, human oocytes were analyzed for TF, galectin-1 expression, and galectin-1 binding. We identified a significant upregulation of MUC1 and TF epitope and, in addition, galectin-1 binding in glandular epithelium and epithelial apical surface tissue from proliferative to secretory phase. With double staining experiments, we identified a coexpression of TF and MUC1 in the early secretory phase and galectin-1 binding to TF during the same period of time. In addition we identified TF epitope and galectin-1 expression plus binding on the human oocyte and irregularly fertilized oocytes. Upregulation of TF epitope on the glandular epithelium and epithelial apical surface tissue in the secretory phase and binding of galectin-1 at the same time show the possibility of galectin-1-mediated trophectoderm binding to the endometrium within the window of implantation.


Assuntos
Antígenos Glicosídicos Associados a Tumores/biossíntese , Endométrio/metabolismo , Galectina 1/metabolismo , Mucina-1/biossíntese , Biotinilação , Linhagem Celular Tumoral , Técnicas de Cocultura , Endométrio/citologia , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Epitopos , Feminino , Fertilização , Glicosilação , Humanos , Imuno-Histoquímica , Ciclo Menstrual , Oócitos/citologia , Oócitos/metabolismo , Pré-Menopausa , Ligação Proteica , Zigoto/citologia , Zigoto/metabolismo
20.
Gynecol Obstet Invest ; 67(4): 269-74, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19339781

RESUMO

Effects of female steroid hormones on endothelial cells are gaining increased importance due to several studies on the effects of hormonal treatment on cardiovascular risk. Recent data argue for an improvement of endothelium-derived relaxation and impaired vascular contraction by estradiol, whereas progesterone and testosterone might entail contrary effects. So far, gestagenic influence on endothelial cell physiology is poorly understood. Human umbilical vein endothelial cells (HUVECs) exposed to the female sex hormones estradiol and progesterone show expression of estrogen receptor-beta (ERbeta) and progesterone receptor A (PR-A), and are negative for ERalpha and PR-B. The aim of this study was to analyze the expression and stimulation of PR-A and -B in HUVECs after stimulation with progesterone and PR antagonists that are commercially available. PR-B expression or upregulation was abrogated after application of progesterone or antagonists to HUVECs. Expression of PR-A could be significantly upregulated with progesterone and mifepristone. Unexpectedly, stimulation with the progesterone antagonist RU486 (mifepristone) was accomplished by an upregulation of PR-A expression in our study. We conclude that gestagenic effects on HUVECs independent of modulators are mediated via the PR-A.


Assuntos
Células Endoteliais/química , Mifepristona/farmacologia , Progesterona/farmacologia , Receptores de Progesterona/análise , Veias Umbilicais/citologia , Células Cultivadas , Humanos , Imuno-Histoquímica , Progesterona/antagonistas & inibidores , Receptores de Progesterona/efeitos dos fármacos
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