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1.
Chem Res Toxicol ; 34(7): 1738-1748, 2021 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-34142820

RESUMEN

Cutaneous drug-induced reactions are immune-mediated responses that can lead to life-threatening diseases such as drug reaction with eosinophilia and systemic symptoms (DRESS), Stevens-Johnson syndrome, and toxic epidermal necrolysis, collectively known as severe cutaneous adverse reactions (SCARs). Unfortunately, they cannot be predicted during drug development, and, at present, a prognostic biomarker is not available nor are validated in vitro assays for diagnosis. Thus, by using proteomic and microarray miRNA analysis, the cargo of extracellular vesicles obtained from SCARs patients was analyzed and correlated with the severity of the reaction. Confirmatory assays using Western blot and qRT-PCR were performed to validate findings, and bioinformatic tools were used to establish the correlation between protein and miRNAs expression between groups. The proteomic analysis showed an increase in the amount of pro-inflammatory proteins, von Willebrand factor, and C-reactive protein and a decrease in anti-inflammatory and protective proteins in the SCARs group compared with the control group. Additionally, histone protein H2A was enriched in DRESS patients. APO1 and SERPINA4 proteins, highly increased in the control group but absent in the SCARs group, are the target of several overexpressed miRNAs, suggesting that the regulation of these proteins might involve gene silencing and protein repressing mechanisms in the severe patients. According with previous reports showing its presence in plasma and T-cells, microRNA miR-18 was upregulated in extracellular vesicles obtained from the most severe patients. Determination of the unique cargo associated with different disease conditions will help to understand the pathophysiology of these complex reactions and might help to develop novel biomarkers for life-threatening iatrogenic cutaneous disease.


Asunto(s)
Erupciones por Medicamentos/genética , Vesículas Extracelulares/genética , MicroARNs/genética , Erupciones por Medicamentos/diagnóstico , Vesículas Extracelulares/química , Vesículas Extracelulares/patología , Humanos , Proteoma/análisis , Proteoma/genética , Proteómica , Transcriptoma
2.
Int J Mol Sci ; 20(5)2019 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-30871076

RESUMEN

The clustered regularly interspaced short palindromic repeat/CRISPR-associated protein 9 (CRISPR/Cas9) technology is a versatile and useful tool to perform genome editing in different organisms ranging from bacteria and yeast to plants and mammalian cells. For a couple of years, it was believed that the system was inefficient and toxic in the alga Chlamydomonas reinhardtii. However, recently the system has been successfully implemented in this model organism, albeit relying mostly on the electroporation of ribonucleoproteins (RNPs) into cell wall deficient strains. This requires a constant source of RNPs and limits the application of the technology to strains that are not necessarily the most relevant from a biotechnological point of view. Here, we show that transient expression of the Streptococcus pyogenes Cas9 gene and sgRNAs, targeted to the single-copy nuclear apt9 gene, encoding an adenine phosphoribosyl transferase (APT), results in efficient disruption at the expected locus. Introduction of indels to the apt9 locus results in cell insensitivity to the otherwise toxic compound 2-fluoroadenine (2-FA). We have used agitation with glass beads and particle bombardment to introduce the plasmids carrying the coding sequences for Cas9 and the sgRNAs in a cell-walled strain of C. reinhardtii (CC-125). Using sgRNAs targeting exons 1 and 3 of apt9, we obtained disruption efficiencies of 3 and 30% on preselected 2-FA resistant colonies, respectively. Our results show that transient expression of Cas9 and a sgRNA can be used for editing of the nuclear genome inexpensively and at high efficiency. Targeting of the APT gene could potentially be used as a pre-selection marker for multiplexed editing or disruption of genes of interest.


Asunto(s)
Adenina Fosforribosiltransferasa/genética , Proteína 9 Asociada a CRISPR/genética , Sistemas CRISPR-Cas/genética , Chlamydomonas reinhardtii/genética , Genes Reporteros/genética , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas/genética , Electroporación/métodos , Edición Génica/métodos , Plásmidos/genética , ARN Guía de Kinetoplastida/genética , Ribonucleoproteínas/genética
3.
Plant Mol Biol ; 98(4-5): 303-317, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30225747

RESUMEN

KEY MESSAGE: Two intercistronic regions were identified as functional intercistronic expression elements (IEE) for the simultaneous expression of aphA-6 and gfp in a synthetic operon in the chloroplast of C. reinhardtii. Chlamydomonas reinhardtii, a biflagellate photosynthetic microalga, has been widely used in basic and applied science. Already three decades ago, Chlamydomonas had its chloroplast genome transformed and to this day constitutes the only alga routinely used in transplastomic technology. Despite the fact that over a 100 foreign genes have been expressed from the chloroplast genome, little has been done to address the challenge of expressing multiple genes in the form of operons, a development that is needed and crucial to push forward metabolic engineering and synthetic biology in this organism. Here, we studied five intercistronic regions and investigated if they can be used as intercistronic expression elements (IEE) in synthetic operons to drive the expression of foreign genes in the chloroplast of C. reinhardtii. The intercistronic regions were those from the psbB-psbT, psbN-psbH, psaC-petL, petL-trnN and tscA-chlN chloroplast operons, and the foreign genes were the aminoglycoside 3'-phosphotransferase (aphA-6), which confers resistance to kanamycin, and the green fluorescent protein gene (gfp). While all the intercistronic regions yielded lines that were resistant to kanamycin, only two (obtained with intercistronic regions from psbN-psbH and tscA-chlN) were identified as functional IEEs, yielding lines in which the second cistron (gfp) was translated and generated GFP. The IEEs we have identified could be useful for the stacking of genes for metabolic engineering or synthetic biology circuits in the chloroplast of C. reinhardtii.


Asunto(s)
Chlamydomonas reinhardtii/genética , Cloroplastos/metabolismo , ADN Intergénico/genética , Genes de Plantas/genética , Operón/genética , Plantas Modificadas Genéticamente/genética , Cloroplastos/genética , Regulación de la Expresión Génica de las Plantas/genética , Ingeniería Genética/métodos , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Kanamicina Quinasa/genética , Kanamicina Quinasa/metabolismo , Ingeniería Metabólica/métodos , Plantas Modificadas Genéticamente/metabolismo
4.
Chem Res Toxicol ; 31(6): 454-461, 2018 06 18.
Artículo en Inglés | MEDLINE | ID: mdl-29644860

RESUMEN

Dysregulation in the expression of microRNAs (miRNAs), single-stranded RNAs which regulate gene expression, has been associated with diseases such as Stevens-Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN), although their cellular origin has not been explored. Thus, the focus of this work was to study expression patterns of reported miRNAs involved in T-cell activation following drug-specific stimulation in peripheral blood mononuclear cells (PBMCs) and drug-specific CD4+ T-cell clones (TCC) from patients with different cutaneous manifestations of delayed-type drug hypersensitivity reactions. CD4+ T-cells from hypersensitive patients were stimulated to proliferate, secreted cytokines (IFN-γ and IL-22), cytolytic molecules (Granzyme B) and up-regulate miRNAs 24 to 48 h after drug exposure. Carbamazepine-specific CD4+ T-cells that proliferated to the greatest extent and secreted the highest levels of IFN-γ showed an up-regulation of miR-18a and miR-155. In contrast, piperacillin-specific CD4+ T-cells displaying high expression of miR-9 and miR-21 showed an association with the extent of proliferation, but not IFN-γ secretion. MiR-155 up-regulation was detected in PBMCs from all hypersensitive patients 24 h after drug treatment, while miR-18a and miR-21 expression was up-regulated after 48 h. These findings demonstrate that miRNAs are expressed during drug-specific CD4+ T-cell activation and shows a new regulation path for drug hypersensitivity reactions.


Asunto(s)
Linfocitos T CD4-Positivos/efectos de los fármacos , MicroARNs/genética , Regulación hacia Arriba , Adulto , Linfocitos T CD4-Positivos/metabolismo , Carbamazepina/farmacología , Citocinas/metabolismo , Hipersensibilidad a las Drogas/genética , Femenino , Humanos , Lamotrigina/farmacología , Activación de Linfocitos , Masculino , Persona de Mediana Edad , Piperacilina/farmacología , Sulfametoxazol/farmacología
5.
J Clin Periodontol ; 40(3): 260-5, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23278672

RESUMEN

AIM: The objective of this prospective study was to investigate outcomes of a lip repositioning technique for the treatment of excessive gingival display. MATERIALS AND METHODS: Thirteen consecutively treated patients with excessive gingival display were treated with a modified lip repositioning technique. Treatment consisted of the removal of two strips of mucosa, bilaterally to the maxillary labial frenum and coronal repositioning of the new mucosal margin. The clinical dimensions of gingival display, upper lip and vermillion length were measured at baseline, 3 and 6 months post-operatively. Subjects completed surveys to evaluate satisfaction with outcomes. RESULTS: The baseline gingival display of 5.8 ± 2.1 mm significantly decreased to 1.4 ± 1.0 mm at 3 months (p < 0.0001) and was maintained until 6 months (1.3 ± 1.6 mm). The reduction in gingival display strongly correlated to the combined change in upper lip and vermillion length (r(2)  = 0.60, p = 0.0018). Subjects were satisfied with their smile after surgery and would likely choose to undergo the procedure again (92%). The worst part of undergoing the procedure was the discomfort or the inability to move the lip during the early healing (69%). CONCLUSION: Treatment of excessive gingival display by means of a modified lip repositioning technique results in high level of patient satisfaction and predictable outcomes that are stable in the short term.


Asunto(s)
Encía/patología , Labio/cirugía , Sonrisa , Adulto , Estética Dental , Femenino , Estudios de Seguimiento , Humanos , Frenillo Labial/cirugía , Labio/patología , Masculino , Persona de Mediana Edad , Mucosa Bucal/cirugía , Dolor Postoperatorio/etiología , Satisfacción del Paciente , Complicaciones Posoperatorias , Estudios Prospectivos , Resultado del Tratamiento , Cicatrización de Heridas/fisiología , Adulto Joven
6.
Mol Biotechnol ; 61(6): 461-468, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30997667

RESUMEN

Synthetic biology and genetic engineering in algae offer an unprecedented opportunity to develop species with traits that can help solve the problems associated with food and energy supply in the 21st century. In the green alga Chlamydomonas reinhardtii, foreign genes can be expressed from the chloroplast genome for molecular farming and metabolic engineering to obtain commodities and high-value molecules. To introduce these genes, selectable markers, which rely mostly on the use of antibiotics, are needed. This has risen social concern associated with the potential risk of horizontal gene transfer across life kingdoms, which has led to a quest for antibiotic-free selectable markers. Phosphorus (P) is a scarce nutrient element that most organisms can only assimilate in its most oxidized form as phosphate (Pi); however, some organisms are able to oxidize phosphite (Phi) to Pi prior to incorporation into the central metabolism of P. As an alternative to the use of the two positive selectable makers already available for chloroplast transformation in C. reinhardtii, the aadA and the aphA-6 genes, that require the use of antibiotics, we investigated if a phosphite-based selection method could be used for the direct recovery of chloroplast transformed lines in this alga. Here we show that following bombardment with a vector carrying the ptxD gene from Pseudomonas stutzeri WM88, only cells that integrate and express the gene proliferate and form colonies using Phi as the sole P source. Our results demonstrate that a selectable marker based on the assimilation of Phi can be used for chloroplasts transformation in a biotechnologically relevant organism. The portable selectable marker we have developed is, in more than 18 years, the latest addition to the markers available for selection of chloroplast transformed cells in C. reinhardtii. The ptxD gene will contribute to the repertoire of tools available for synthetic biology and genetic engineering in the chloroplast of C. reinhardtii.


Asunto(s)
Proteínas Bacterianas/genética , Chlamydomonas reinhardtii/genética , Cloroplastos/genética , NADH NADPH Oxidorreductasas/genética , Fosfitos/metabolismo , Fósforo/metabolismo , Proteínas Algáceas/genética , Proteínas Algáceas/metabolismo , Proteínas Bacterianas/metabolismo , Chlamydomonas reinhardtii/metabolismo , Cloroplastos/metabolismo , Ingeniería Genética/métodos , Marcadores Genéticos , Vectores Genéticos/química , Vectores Genéticos/metabolismo , NADH NADPH Oxidorreductasas/metabolismo , Fosfitos/farmacología , Pseudomonas stutzeri/química , Pseudomonas stutzeri/genética , Selección Genética , Transformación Genética
7.
Clin Adv Periodontics ; 9(1): 15-19, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-31490037

RESUMEN

INTRODUCTION: The peripheral ossifying fibroma (POF) is a benign reactive lesion that exclusively arises from gingiva. The lesion may gain considerably large sizes and present peculiar clinical and radiographic features that would then allow it to be called a giant POF; in that case, its otherwise simple surgical extraction could create a challenge. Thus, we elect here, for the very first time, a plausible alternative for treating giant POF: piezosurgery followed by placement of platelet-rich fibrin (PRF). CASE PRESENTATION: A 31-year-old black male presented a large asymptomatic nodule on the lower gingiva; the lesion had caused vestibular displacement of teeth and had been present for 18 years. Following the diagnostic hypothesis of a giant POF, an excisional biopsy was performed under local anesthesia using piezosurgery (microvibration of 36,000 times/sec was used in a bone cortical working mode), which confirmed the diagnosis. The surgical procedure was facilitated with the use of piezosurgery followed by placement of PRF, being the trans- and postoperative periods occurred with no complications. One year after the treatment, the patient shows no signs of disease recurrence and remains under follow-up. CONCLUSIONS: Giant POF is a rare gingival reactive lesion that can reach large dimensions, causing teeth displacement, functional, and esthetic impairments. The lesion can be successfully managed with piezosurgery and PRF, as illustrated herein, avoiding extensive bone loss and damage to the surrounding soft tissues.


Asunto(s)
Fibroma Osificante , Enfermedades de las Encías , Piezocirugía , Fibrina Rica en Plaquetas , Adulto , Fibroma Osificante/terapia , Enfermedades de las Encías/terapia , Humanos , Masculino , Recurrencia Local de Neoplasia
8.
Methods Mol Biol ; 1932: 175-185, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30701500

RESUMEN

microRNAs are noncoding RNAs of 20-24 nucleotides (nt) in length that act as repressors of genes and are important in key developmental processes in the entire life cycle of plants. To determine the function of a microRNA, the first step is to resolve its expression pattern; this can be achieved by in situ hybridization, RNA blot assays, or quantitative PCR. However, the study of the expression of a MIR gene is straightforward with the use of reporter proteins such as ß-D-glucuronidase (GUS), GFP, or mCherry. To do this, it is necessary to clone the promoter region of the MIR gene and place it upstream of the reporter gene; in this way the activity of the promoter will be a direct reflection of the expression of the MIR gene. Here, we indicate step by step how to make transcriptional fusion constructs from the cloning of a promoter region of a MIR gene fused to the classical reporter proteins GUS and mCherry, the latter with codon optimization for better expression in Arabidopsis thaliana. This method is particularly useful to dissect the promoter region of a MIR gene and to find its expression pattern in a tissue and developmental specific manner.


Asunto(s)
Arabidopsis/genética , Regulación de la Expresión Génica de las Plantas/genética , MicroARNs/genética , ARN de Planta/genética , Proteínas Recombinantes de Fusión/genética , Clonación Molecular , Genes de Plantas/genética , Genes Reporteros/genética , Glucuronidasa/genética , Regiones Promotoras Genéticas/genética , Transcripción Genética/genética
9.
J Biotechnol ; 251: 186-188, 2017 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-28359866

RESUMEN

Light-up aptamers are practical tools to image RNA localization in vivo. A now classical light-up aptamer system is the combination of the 3,5-difluoro-4-hydroxybenzylidene (DFHBI) fluorogen and the RNA aptamer Spinach, which has been successfully used in bacterial and mammalian cells. However, light-up aptamers have not been used in algae. Here, we show that a simple vector, carrying Spinach, transcriptionally fused to the aphA-6 gene, can be effectively used to generate a functional light-up aptamer in the chloroplast of Chlamydomonas reinhardtii. After incubation with DFHBI, lines expressing the aphA-6/Spinach mRNA were observed with laser confocal microscopy to evaluate the functionality of the light-up aptamer in the chloroplast of C. reinhardtii. Clear and strong fluorescence was localized to the chloroplast, in the form of discrete spots. There was no background fluorescence in the strain lacking Spinach. Light-up aptamers could be further engineered to image RNA or to develop genetically encoded biosensors in algae.


Asunto(s)
Aptámeros de Nucleótidos/genética , Chlamydomonas reinhardtii/genética , Cloroplastos/genética , Compuestos de Bencilo , Fluorescencia , Colorantes Fluorescentes , Imidazolinas , Kanamicina Quinasa/genética , ARN Mensajero/genética , ARN de Planta/genética
10.
Biochimie ; 88(6): 725-35, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16483707

RESUMEN

In the present work we have used a double-hybrid assay in bacteria to identify a putative domain in E. coli PNPase required for in vivo interaction with RNase E. We used a 202 aa fragment of RNase E previously reported as the PNPase binding domain in this enzyme and a collection of 13 different fragments of 105 aa, spanning the entire sequence of 734 aa PNPase (GenBank Accession number NP_417633). Our results indicate that two clones of PNPase including residues 158-262 and residues 473-577 contain interaction sites for RNase E within a betabetaalphabetabetaalpha domain configuration. Three-dimensional modeling of the E. coli PNPase based on the S. antibioticus protein structure indicates that the putative binding domain is located on the monomer surface, facing outward from the trimeric tertiary structure. Since a copy of the betabetaalphabetabetaalpha domain is also found in RNase PH, we investigated and found an interaction with RNase E in a pull-down assay. We suggest this interaction takes place through the similar betabetaalphabetabetaalpha domain present in the tertiary structure of this enzyme. Based on these results, we propose that RNase PH and RNase E could form functional assemblies in E. coli.


Asunto(s)
Endorribonucleasas/metabolismo , Polirribonucleótido Nucleotidiltransferasa/química , Polirribonucleótido Nucleotidiltransferasa/metabolismo , Escherichia coli , Modelos Moleculares , Unión Proteica , Estructura Cuaternaria de Proteína , Estructura Terciaria de Proteína , Subunidades de Proteína/química
11.
Oncogene ; 16(15): 1931-8, 1998 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-9591776

RESUMEN

The dihydrofolate reductase (dhfr) promoter is powerfully activated by the transcription factor Sp1. It has been suggested that Sp1 is a potential target for transcriptional regulation by the cell cycle regulator retinoblastoma protein (Rb), and so we have explored this possibility using the hamster dhfr gene as a model. By the use of DNA probes from the hamster dhfr gene promoter, containing the most proximal GC box (minimal promoter), and nuclear extracts from cultured hamster cells (CHO K1), we show that polyclonal and monoclonal antibodies against Rb supershift the binding of Sp1. Nuclear extract immunoprecipitation with anti-Rb followed by Western analysis using anti-Sp1 also shows that Rb is complexed to Sp1. Complementary Immunoprecipitation/WB analysis shows both forms of Rb protein in the anti-Sp1 immunoprecipitates. Moreover, nuclear extract immunodepletion of Rb abolishes Sp1 gel-shift. The interaction between Rb and Sp1 is maintained in all the phases of the cell cycle. Transient overexpression of Rb in dhfr negative cells co-transfected with a dhfr minigene driven by its minimal promoter increases DHFR activity and potentiates transcription when overexpressing Sp1. Both effects are severely reduced when the co-transfections are performed with a homologous dhfr minigene containing a single point mutation in the GC box. Thus, the activation by Rb of the dhfr gene may be exerted through Sp1. Stable transfectants of pCMVRb in K1 cells show an increase in both mRNA and DHFR activity. It is concluded that Sp1 is physically associated with Rb, and that this association increases Sp1-mediated transcription of the hamster dhfr gene.


Asunto(s)
Proteínas Portadoras , Proteínas de Ciclo Celular , Proteínas de Unión al ADN , Regiones Promotoras Genéticas , Proteína de Retinoblastoma/metabolismo , Factor de Transcripción Sp1/metabolismo , Tetrahidrofolato Deshidrogenasa/genética , Animales , Células CHO , Ciclo Celular , Cricetinae , Factores de Transcripción E2F , Proteína 1 de Unión a Retinoblastoma , Factores de Transcripción/metabolismo , Transfección
12.
Oncogene ; 17(16): 2059-71, 1998 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-9798677

RESUMEN

Fibroblast Growth Factors 3 (FGF-3) and 4 (FGF-4) were compared for the effects they each exert on EF43 mouse cells. This non-transformed mammary cell line appears to be myoepithelial mainly because it expresses alpha-smooth muscle actin. The EF43 cells were infected with similar vectors that carry either the short fgf-3 sequence (the product of which goes into the secretory pathway), fgf-4 or the selection gene only as control. In syngeneic animals, EF43.fgf-3 cells were tumorigenic only when orthotopically implanted whereas EF43.fgf-4 cells invariably gave rise to aggressive tumors. However, both tumor types were metastatic as evidenced by the blue micrometastases observed when the implanted cells expressed lacZ. In vitro, the FGF-3 producing cells were strongly invasive in matrigel coated chambers whereas the EF43.fgf-4 cells only were invasive in type I-collagen gels. Interestingly, FGF-3 production greatly stimulated the synthesis of pro-MMP-9 (Matrix Metalloprotease-9) and, to a lesser extent, that of pro-MMP-2. FGF-3 also up-regulated the production of plasminogen activators. In contrast, FGF-4 had no effect on these secretions and the medium conditioned by the EF43.fgf-4 cells displayed the largest plasminogen activator-inhibitor activity. These results show that FGF-3 and FGF-4 have distinct mechanisms of action on myoepithelial cells.


Asunto(s)
Transformación Celular Neoplásica , Factores de Crecimiento de Fibroblastos/fisiología , Glándulas Mamarias Animales/patología , Proteínas Proto-Oncogénicas/fisiología , Animales , Línea Celular , Colagenasas/metabolismo , Células Epiteliales , Femenino , Factor 3 de Crecimiento de Fibroblastos , Factor 4 de Crecimiento de Fibroblastos , Factores de Crecimiento de Fibroblastos/genética , Gelatinasas/metabolismo , Metaloproteinasa 2 de la Matriz , Metaloproteinasa 9 de la Matriz , Metaloendopeptidasas/metabolismo , Ratones , Ratones Endogámicos BALB C , Metástasis de la Neoplasia , Trasplante de Neoplasias , Inactivadores Plasminogénicos/metabolismo , Proteínas Proto-Oncogénicas/genética , Activador de Tejido Plasminógeno/metabolismo , Activador de Plasminógeno de Tipo Uroquinasa/metabolismo
13.
Biochim Biophys Acta ; 1495(3): 319-26, 2000 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-10699469

RESUMEN

RNA-based arbitrarily primed PCR (RAP-PCR) was used to identify sequences in CHO K1 cells that were differentially expressed upon methotrexate incubation during the development of resistance to this drug. Ten different RAP products were isolated, cloned and sequenced. Among these, we identified one sequence that showed 84% identity with the nucleotide sequence of rat cytochrome c oxidase subunit II, and 90% identity with the amino acid sequence of this protein. This RAP fragment was up-regulated in a dose- and time-dependent manner. The overexpression of cytochrome c oxidase subunit II mRNA as a result of methotrexate incubation was corroborated by quantitative RT-PCR and Northern blot analysis. Incubation of cells with sodium azide, a specific cytochrome c oxidase inhibitor, decreased the number of resistant colonies after methotrexate treatment. Thus, overexpression of cytochrome c oxidase is involved in the development of resistance to methotrexate. These results suggest that sodium azide may be used as a modulator in chemotherapy with methotrexate.


Asunto(s)
Antimetabolitos Antineoplásicos/farmacología , Complejo IV de Transporte de Electrones/metabolismo , Metotrexato/farmacología , Animales , Células CHO , Supervivencia Celular/efectos de los fármacos , Cricetinae , Interacciones Farmacológicas , Resistencia a Medicamentos/fisiología , Complejo IV de Transporte de Electrones/antagonistas & inhibidores , Complejo IV de Transporte de Electrones/genética , Inhibidores Enzimáticos/farmacología , Reacción en Cadena de la Polimerasa/métodos , ARN Mensajero/análisis
14.
FEBS Lett ; 363(3): 289-92, 1995 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-7737419

RESUMEN

A synthetic HAV-containing decapeptide homologous to the amino acid sequence 44R-Q53 in rat extracellular superoxide dismutase B affects cadherin-dependent cell aggregation. Cell lines, some of them transfected, expressing different types of cadherins were tested using in vitro cell aggregation and cell dissociation assays. A concentration-dependent inhibition of aggregation by the EC-SOD-derived HAV-containing peptide was detected only in N-cadherin expressing cells. These results suggest the localisation and possible protective role of EC-SOD B for cells expressing N-cadherin.


Asunto(s)
Cadherinas/farmacología , Agregación Celular/efectos de los fármacos , Superóxido Dismutasa/química , Secuencia de Aminoácidos , Animales , Humanos , Células L , Ratones , Datos de Secuencia Molecular , Fragmentos de Péptidos/farmacología , Ratas , Proteínas Recombinantes , Superóxido Dismutasa/farmacología , Transfección
15.
Biochem Soc Symp ; 65: 43-62, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10320932

RESUMEN

The E-cadherin-catenin complex is pivotal for the regulation of cancer invasion. It not only serves cell-cell adhesion but also transduces signals from the micro-environment to other molecular complexes possibly implicated in invasion. Both functions are disturbed when the extracellular part of E-cadherin is cleaved off. Moreover, upon release into the environment, the E-cadherin fragments may interfere with intact complexes, as indicated by experiments with His-Ala-Val (HAV)-containing peptides that are homologous to parts of the first extracellular domain of E-cadherin. Scatter factor/hepatocyte growth factor (SF/HGF), on binding to its c-met tyrosine kinase receptor, can induce invasion through tyrosine phosphorylation of beta-catenin. SF/HGF-induced invasion is also associated with phosphorylation of pp125FAK, and both invasion and phosphorylation are inhibited by platelet-activating factor (PAF). Activation of the membrane-bound non-receptor tyrosine kinase pp60src can also induce invasion. Signal transduction pathways starting from pp60src include E-cadherin-associated beta-catenin as well as the focal adhesion kinase pp125FAK. Whereas all invasion-inducing pathways implicate phosphoinositide 3-kinase, the PAF pathway seems to be E-cadherin-catenin-independent. We conclude that cancer cell invasion is regulated by paracrine and autocrine factors that are released upon cross-talk with the host cells.


Asunto(s)
Cadherinas/metabolismo , Proteínas del Citoesqueleto/metabolismo , Matriz Extracelular/metabolismo , Invasividad Neoplásica , Transactivadores , Secuencia de Aminoácidos , Animales , Factor de Crecimiento de Hepatocito/metabolismo , Humanos , Proteínas Proto-Oncogénicas pp60(c-src)/metabolismo , beta Catenina
16.
Clin Exp Metastasis ; 17(3): 245-53, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10432010

RESUMEN

We have investigated the role of sialylation on cell-cell adhesion mediated by E-cadherin. Two MCF-7 human breast cancer cell variants were studied: MCF-7/AZ cells showed a spontaneous cell-cell adhesion in the fast and slow aggregation assay. whereas the adhesion deficient MCF-7/6 cell variant failed to form larger aggregates, suggesting that E-cadherin was not functional under the conditions of both assays. We measured the sialyltransferase activities using Galbeta1-3GalNAcalpha-O-benzyl and Galbeta1-4GlcNAcalpha-O-benzyl as acceptor substrates as well as mRNA levels of four sialyltransferases, ST3Gal I, ST3Gal III, ST3Gal IV, ST6Gal I, using multiplex RT-PCR in MCF-7 cell variants. The alpha2-6 and alpha2-3 sialylation of E-cadherin was investigated by immuno-blot using Sambucus nigra agglutinin and Maackia amurensis agglutinin. Compared to the adhesion-proficient MCF-7/AZ cells, the adhesion-deficient MCF-7/6 cell line apparently lacks ST6Gal I mRNA, has a lower ST3Gal I mRNA, a lower ST3Gal I sialyltransferase activity, and no alpha2-3 linked sialic acid moieties on E-cadherin. The potential anti-cancer drug 1-O-octadecyl-2-O-methylglycero-3-phosphocholine (ET-18-OMe, 48 h, 25 microg/ml) belonging to the class of alkyllysophospholipids restored the E-cadherin function in the adhesion-deficient MCF-7/6 cells as evidenced by an increased aggregation. ET-18-OMe caused loss of ST6Gal I mRNA in MCF-7/AZ cells but no changes of sialyltransferase activities or sialic acid moieties on E-cadherin could be observed. We conclude that Ca2+-dependent, E-cadherin-specific homotypic adhesion of MCF-7/AZ or MCF-7/6 cells treated with ET-18-OMe was not affected by sialylation of E-cadherin.


Asunto(s)
Antineoplásicos/farmacología , Neoplasias de la Mama/patología , Cadherinas/metabolismo , Inhibidores de Fosfodiesterasa/farmacología , Éteres Fosfolípidos/farmacología , Ácidos Siálicos/metabolismo , Neoplasias de la Mama/enzimología , Neoplasias de la Mama/metabolismo , Agregación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Femenino , Glicoproteínas/metabolismo , Humanos , Immunoblotting , Pruebas de Precipitina , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Sialiltransferasas/biosíntesis , Sialiltransferasas/metabolismo , Células Tumorales Cultivadas
17.
Biochem Pharmacol ; 50(3): 337-46, 1995 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-7646535

RESUMEN

Phorbol 12-myristate 13-acetate (TPA) increases the number of colonies surviving methotrexate (MTX) exposure in a dose-dependent manner upon short incubation with Chinese hamster ovary (CHO) cells. Seventy percent of the isolated colonies showed increased copy number for the dihydrofolate reductase gene. EGTA prevents the increase in resistance triggered by TPA. Calcium ionophore A23187 and angiotensin II also increase this resistance, suggesting that calcium is involved in this process. Protein kinase C (PKC) from CHO cells is rapidly activated by TPA, A23187 and angiotensin II. PKC inhibitors, 1-(5-Isoquinolinylsulphonyl)-2-methyl-piperazine (H-7), glycyrrhetinic acid, staurosporine and calphostin C decrease the generation of resistant colonies to MTX upon incubation with TPA. However, 5 nM staurosporine on its own increases resistance to MTX while having the ability to translocate CHO PKC. In vitro, H-7, staurosporine and calphostin C inhibit PKC activity translocated by TPA incubation with CHO cells. We conclude that PKC, the activity of which is dependent on calcium and phospholipids, is part of the pathway that leads to development of increased resistance to MTX. Thus, inhibition of PKC prevents the appearance of this resistance. Our results suggest the possibility of using non-toxic PKC inhibitors as resistance modulators in MTX chemotherapy.


Asunto(s)
Metotrexato/farmacología , Ésteres del Forbol/farmacología , Proteína Quinasa C/antagonistas & inhibidores , 1-(5-Isoquinolinesulfonil)-2-Metilpiperazina , Alcaloides/farmacología , Animales , Secuencia de Bases , Células CHO , Ensayo de Unidades Formadoras de Colonias , Cricetinae , Resistencia a Medicamentos , Ácido Glicirretínico/farmacología , Isoquinolinas/farmacología , Datos de Secuencia Molecular , Naftalenos/farmacología , Piperazinas/farmacología , Estaurosporina
18.
Atherosclerosis ; 233(1): 178-85, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24529141

RESUMEN

The transcription of the Low-density lipoprotein receptor-related protein (LRP1) is upregulated by aggregated LDL (agLDL) and angiotensin II (AngII) in human vascular smooth muscle cells (hVSMC). The polymorphism c.1-25C>G creates a new GC-box in the LRP1 promoter recognized by Sp1/Sp3 transcription factors. The aims of this study were 1) to evaluate the impact of c.1-25C>G polymorphism on LRP1 transcriptional activity and expression, and 2) to examine the response of c.1-25C>G LRP1 promoter to LDL and AngII. EMSA and Luciferase assays in HeLa cells showed that -25G promoter has enhanced basal transcriptional activity and specific Sp1/Sp3 binding. hVSMC with GG genotype (GG-hVSMC) had higher LRP1 mRNA and protein levels, respectively than CC genotype (CC-hVSMC). EMSA assays showed that the polymorphism determines scarce amount of SRE-B/SREBP-2 complex formation and the failure of agLDL to further reduce these SRE-B/SREBP-2 complexes. Taken together, these results suggest that c.1-25C>G, by difficulting SREBP-2 binding, prevents SREBP-2 displacement required for LRP1 promoter response to LDL. In contrast, c.1-25C>G strongly favours Sp1/Sp3 binding and AngII-induced activity in Sp1/Sp3 dependent manner in GG-hVSMC. This increase is functionally translated into a higher capacity of GG-hVSMC to become foam cells from agLDL in presence of AngII. These results suggest that c.1-25C>G determines a lack of response to agLDL and an exacerbated response to AngII. It is thus conceivable that the presence of the polymorphism would be easily translated to vascular alterations in the presence of the pro-hypertensive autacoid, AngII.


Asunto(s)
Proteína 1 Relacionada con Receptor de Lipoproteína de Baja Densidad/genética , Regiones Promotoras Genéticas/genética , Factor de Transcripción Sp1/metabolismo , Factor de Transcripción Sp3/metabolismo , Angiotensina II/fisiología , Sitios de Unión , Células HeLa , Humanos , Lipoproteínas LDL/metabolismo , Proteína 1 Relacionada con Receptor de Lipoproteína de Baja Densidad/biosíntesis , Músculo Liso Vascular/citología , Músculo Liso Vascular/metabolismo , Polimorfismo Genético , Proteína 2 de Unión a Elementos Reguladores de Esteroles/biosíntesis , Activación Transcripcional
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