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Caspasa 3 , Ganciclovir , Neoplasias Ováricas , Simplexvirus , Timidina Quinasa , Humanos , Femenino , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/genética , Neoplasias Ováricas/metabolismo , Neoplasias Ováricas/patología , Timidina Quinasa/genética , Timidina Quinasa/metabolismo , Simplexvirus/genética , Ganciclovir/farmacología , Ganciclovir/uso terapéutico , Caspasa 3/metabolismo , Muerte Celular/efectos de los fármacos , Línea Celular TumoralRESUMEN
PURPOSE: To evaluate the outcomes of REPA and establish if any differences in complications and evolution are present between males and females. METHODS: A retrospective study including consecutive patients operated by REPA approach between November 2017 and April 2019 was conducted. Demographic data, operative times, postoperative complications, and hospital stay were analyzed. The EuraHS-QoL score was used to assess postoperative pain, daily activity constraints, and aesthetic discomfort. The results were compared between sexes. Statistical analysis was performed using SPSS 19. RESULTS: Fifty-four patients were included and 53.7% were male. Patients had a mean age of 50.7 years and a mean BMI of 28.7. The average RAD (Rectus Abdominis Diastasis) size was 2.6 cm (range of 2-5 cm). Seroma was significantly more frequent in males, with an incidence of 55.2 and 24% for females (p = 0.02). Three cases required reintervention (5.5% of total cases), which corresponded to a cystic seroma, an abdominal wall hematoma, and a hernia recurrence. The three cases were males and a p value of 0.04 was obtained when comparing reintervention rates between males and females. No cases of surgical wound infection nor cutaneous necrosis were recorded. No conversions were needed. The mean postoperative pain was 2.25, the mean daily activity constraints score was 2.63, and the degree of aesthetic discomfort was 1.23 with no significant differences between groups. CONCLUSION: The correction of small midline defect associated with minor RAD using REPA seems feasible and reproducible. REPA had achieved good results in females, but in males, the outcomes were poorer.
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Hernia Ventral , Calidad de Vida , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Seroma , Herniorrafia/métodos , Dolor Postoperatorio/etiología , Mallas Quirúrgicas/efectos adversos , Hernia Ventral/cirugía , RecurrenciaRESUMEN
In this chapter, a protocol to design affinity chromatography matrices with short peptide ligands immobilized for protein purification is described. The first step consists of the synthesis of a combinatorial peptide library on the hydroxymethylbenzoyl (HMBA)-ChemMatrix resin by the divide-couple-recombine (DCR) method using the Fmoc chemistry. Next, the library is screened with the protein of interest labeled with a fluorescent dye or biotin. Subsequently, peptides contained on positive beads are identified by tandem matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS/MS), and those sequences showing greater consensus are synthesized in larger quantities and immobilized on chromatographic supports. Finally, target protein adsorption on peptide affinity matrices is evaluated through equilibrium adsorption isotherms and breakthrough curves.
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Cromatografía de Afinidad , Técnicas Químicas Combinatorias , Biblioteca de Péptidos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización DesorciónRESUMEN
Amphibian secretion is an important source of bioactive molecules that naturally protect the skin against noxious microorganisms. Collectively called antimicrobial peptides (AMPs), these molecules have a wide spectrum of action, targeting viruses, bacteria and fungi. Like many membrane and secreted proteins, AMPs have cleavable signal sequences that mediate and translocate the nascent polypeptide chains into the endoplasmic reticulum. Although it is accepted that the signal peptides (SPs) are simple and interchangeable, there is neither sequence nor structure that is conserved among all gene families. They derived from a common ancestor but developed different traits as they adapt to distinct environmental pressures. The aim of this study was to provide anoverview of the diversity of SPs of the frog, taking into account reported cDNA sequences and the evolutionary relationship among them. We analysed more than 2000 records that reported the relative abundance, diversity and evolutionary divergence based on the peptide signals of frog AMPs. We conclude that the physical properties of the sequence are more important than the specific peptidesin AMP SPs. Since there is significant overlapping among related genera, differences in secretion from different peptide types should be regulated by additional levels, such as posttranscriptional modifications or 5-UTR sequences.
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Proteínas Anfibias/genética , Anfibios/genética , Antibacterianos/metabolismo , Péptidos Catiónicos Antimicrobianos/genética , Bacterias/metabolismo , Señales de Clasificación de Proteína/genética , Piel/metabolismo , Proteínas Anfibias/metabolismo , Anfibios/metabolismo , Animales , Péptidos Catiónicos Antimicrobianos/metabolismoRESUMEN
Reprogramming of cellular metabolism towards de novo serine production fuels the growth of cancer cells, providing essential precursors such as amino acids and nucleotides and controlling the antioxidant and methylation capacities of the cell. The enzyme serine hydroxymethyltransferase (SHMT) has a key role in this metabolic shift, and directs serine carbons to one-carbon units metabolism and thymidilate synthesis. While the mitochondrial isoform of SHMT (SHMT2) has recently been identified as an important player in the control of cell proliferation in several cancer types and as a hot target for anticancer therapies, the role of the cytoplasmic isoform (SHMT1) in cancerogenesis is currently less defined. In this paper we show that SHMT1 is overexpressed in tissue samples from lung cancer patients and lung cancer cell lines, suggesting that, in this widespread type of tumor, SHMT1 plays a relevant role. We show that SHMT1 knockdown in lung cancer cells leads to cell cycle arrest and, more importantly, to p53-dependent apoptosis. Our data demonstrate that the induction of apoptosis does not depend on serine or glycine starvation, but is because of the increased uracil accumulation during DNA replication.
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Adenocarcinoma/genética , Regulación Neoplásica de la Expresión Génica , Glicina Hidroximetiltransferasa/antagonistas & inhibidores , Neoplasias Pulmonares/genética , Proteína p53 Supresora de Tumor/genética , Uracilo/metabolismo , Adenocarcinoma/enzimología , Adenocarcinoma/patología , Apoptosis/genética , Puntos de Control del Ciclo Celular , Línea Celular Tumoral , Glicina Hidroximetiltransferasa/genética , Glicina Hidroximetiltransferasa/metabolismo , Humanos , Neoplasias Pulmonares/enzimología , Neoplasias Pulmonares/patología , Mitocondrias/enzimología , Mitocondrias/patología , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Serina/metabolismo , Proteína p53 Supresora de Tumor/metabolismoRESUMEN
Cancer cells are characterized by altered ubiquitination of many proteins. The ubiquitin-specific protease 2a (USP2a) is a deubiquitinating enzyme overexpressed in prostate adenocarcinomas, where it exhibits oncogenic behavior in a variety of ways including targeting c-Myc via the miR-34b/c cluster. Here we demonstrate that USP2a induces drug resistance in both immortalized and transformed prostate cells. Specifically, it confers resistance to typically pro-oxidant agents, such as cisplatin (CDDP) and doxorubicin (Doxo), and to taxanes. USP2a overexpression protects from drug-induced oxidative stress by reducing reactive oxygen species (ROS) production and stabilizing the mitochondrial membrane potential (ΔΨ), thus impairing downstream p38 activation and triggering of apoptosis. The molecular mediator of the USP2a protective function is the glutathione (GSH). Through miR-34b/c-driven c-Myc regulation, USP2a increases intracellular GSH content, thus interfering with the oxidative cascade triggered by chemotherapeutic agents. In light of these findings, targeting Myc and/or miR-34b/c might revert chemo-resistance.
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Antineoplásicos/farmacología , Endopeptidasas/metabolismo , Antioxidantes/metabolismo , Línea Celular Tumoral , Resistencia a Antineoplásicos/efectos de los fármacos , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Depuradores de Radicales Libres/metabolismo , Glutatión/metabolismo , Humanos , Masculino , MicroARNs/metabolismo , Modelos Biológicos , Oxidantes/toxicidad , Oxidación-Reducción/efectos de los fármacos , Próstata/efectos de los fármacos , Próstata/metabolismo , Próstata/patología , Proteínas Proto-Oncogénicas c-myc/genética , Proteínas Proto-Oncogénicas c-myc/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Ubiquitina TiolesterasaRESUMEN
Several epidemiological studies have shown that high levels of melatonin, an indolic hormone secreted mainly by the pineal gland, reduce the risks of developing cancer, thus suggesting that melatonin triggers the activation of tumor-suppressor pathways that lead to the prevention of malignant transformation. This paper illustrates that melatonin induces phosphorylation of p53 at Ser-15 inhibiting cell proliferation and preventing DNA damage accumulation of both normal and transformed cells. This activity requires p53 and promyelocytic leukemia (PML) expression and efficient phosphorylation of p53 at Ser-15 residue. Melatonin-induced p53 phosphorylation at Ser-15 residue does not require ataxia telangiectasia-mutated activity, whereas it is severely impaired upon chemical inhibition of p38 mitogen-activated protein kinase activity. By and large, these findings imply that the activation of the p53 tumor-suppressor pathway is a critical mediator of melatonin and its anticancer effects. Therefore, it provides molecular insights into increasing observational evidence for the role that melatonin has in cancer prevention.
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Antioxidantes/farmacología , Daño del ADN/efectos de los fármacos , Melatonina/farmacología , Serina/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Animales , Proteínas de la Ataxia Telangiectasia Mutada , Proteínas de Ciclo Celular/metabolismo , Línea Celular , Proliferación Celular/efectos de los fármacos , Proteínas de Unión al ADN/metabolismo , Inhibidores Enzimáticos/farmacología , Flavonoides/farmacología , Humanos , Imidazoles/farmacología , Ratones , Proteínas Nucleares/metabolismo , Fosforilación , Proteína de la Leucemia Promielocítica , Proteínas Serina-Treonina Quinasas/metabolismo , Piridinas/farmacología , Factores de Transcripción/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/antagonistas & inhibidores , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismoRESUMEN
Activating mutations in the KRAS gene are among the most prevalent genetic changes in human cancers. To identify synthetic lethal interactions in cancer cells harbouring mutant KRAS, we performed a large-scale screen in isogenic paired colon cancer cell lines that differ by a single allele of mutant KRAS using an inducible short hairpin RNA interference library. Snail2, a zinc finger transcriptional repressor encoded by the SNAI2 gene, was found to be selectively required for the long-term survival of cancer cells with mutant KRAS that have undergone epithelial-mesenchymal transition (EMT), a transdifferentiation event that is frequently seen in advanced tumours and is promoted by RAS activation. Snail2 expression is regulated by the RAS pathway and is required for EMT. Our findings support Snail2 as a possible target for the treatment of the broad spectrum of human cancers of epithelial origin with mutant RAS that have undergone EMT and are characterized by a high degree of chemoresistance and radioresistance.
Asunto(s)
Transformación Celular Neoplásica/genética , Neoplasias Colorrectales/genética , Genes ras , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Línea Celular Tumoral , Transformación Celular Neoplásica/metabolismo , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/terapia , Regulación Neoplásica de la Expresión Génica , Técnicas de Silenciamiento del Gen , Células HCT116 , Humanos , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas p21(ras) , Transducción de Señal , Factores de Transcripción de la Familia Snail , Factores de Transcripción/biosíntesis , Dedos de Zinc/genética , Proteínas ras/genética , Proteínas ras/metabolismoRESUMEN
Both the incidence and prevalence of human immunodeficiency virus infection are increasing in the world. Diseases of ENT districts are more frequent in human immunodeficiency virus-infected patients and involve all the otolaryngological sites. The otorhinolaryngological manifestations in association with HIV infection are mainly atypical, so common in the clinical practice, really aspecific and very frequent in ENT daily routine (such as sinusitis, otitis, etc.) and, therefore, immunodeficiency may not be suspected. In other cases, ENT evidence is more peculiar or unusual, such as opportunistic infections, rare neoplasm and tumours with an unusual course, giving a very high suspect of a human immunodeficiency virus-related infection. The most frequent malignant neoplasm is Kaposi's Sarcoma which is extremely rare in non-human immunodeficiency virus-infected subjects; the second most frequent is non-Hodgkin's lymphoma with 50% in extranodal sites (oral and maxillary sinus). Following a review of the literature, modifications caused by current antiretroviral treatment on head and neck manifestations of human immunodeficiency virus infection have been evaluated. Highly active antiretroviral therapy is a new therapeutic strategy, based on poly-chemo-therapeutic schemes, providing simultaneously two or more anti-retroviral drugs. We have used highly active antiretroviral therapy in human immunodeficiency virus infection since 1997, substituting previous mono-chemotherapy based on Zidovudine or Didanosine alone. Highly active antiretroviral therapy is extremely efficient in reducing the viral load of human immunodeficiency virus and increasing CD4+ T-lymphocyte count. These biological effects are associated with an improvement in immune functions. To evaluate the effects of highly active antiretroviral therapy on otorhinolaryngological manifestations in human immunodeficiency virus infection, we performed a retrospective study on 470 adults, observed over 14 years (1989-2002) and constantly receiving the same treatment, with follow-up from 7 to 80 months. A total of 250 subjects underwent mono-antiretroviral chemotherapy (1989-1996), while 220 underwent highly active antiretroviral therapy (1997-2002). The results of the retrospective study showed that highly active antiretroviral therapy has greatly improved the control of the immune-deficiency (increasing the range of CD4+), reducing the number of otorhinolaryngological manifestations (also tumours). On the other hand, 2 patients presented sudden unilateral hearing loss following treatment: toxicity due to association of new drugs cannot be excluded.
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Terapia Antirretroviral Altamente Activa/métodos , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Linfoma no Hodgkin/epidemiología , Sarcoma de Kaposi/epidemiología , Adulto , Antígenos CD4/inmunología , Didanosina/uso terapéutico , Quimioterapia Combinada , Femenino , Estudios de Seguimiento , Infecciones por VIH/inmunología , Humanos , Incidencia , Masculino , Prevalencia , Infecciones por Pseudomonas/epidemiología , Zidovudina/uso terapéuticoRESUMEN
We have constructed Ad CMV-Smac, a recombinant adenovirus encoding Smac/DIABLO, the recently described second mitochondrial activator of caspases. Transfection of ovarian carcinoma cells with Ad CMV-Smac at multiplicities of infection of 3-60 pfu/cell leads to increasing apoptosis in a dose-dependent manner. Western blot analysis confirms that Smac-induced apoptosis proceeds via a pathway mediated primarily by caspase-9 that can be inhibited by zLEHD-fmk and overexpression of the X-linked inhibitor of apoptosis protein (XIAP). In contrast, there is no cleavage of either caspase-8 or caspase-12. Ad CMV-Smac appears to induce apoptosis independently of cytochrome c release from mitochondria and is not inhibited by overexpression of Bcl-2. Ad CMV-Smac can combine with other proapoptotic factors, such as cisplatin, paclitaxel, and procaspase-3, to produce greater levels of apoptosis in transfected cells.
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Apoptosis/genética , Carcinoma/enzimología , Proteínas Portadoras/metabolismo , Caspasas/metabolismo , Regulación Neoplásica de la Expresión Génica/genética , Proteínas Mitocondriales/metabolismo , Neoplasias Ováricas/enzimología , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Proteínas Reguladoras de la Apoptosis , Carcinoma/tratamiento farmacológico , Carcinoma/genética , Proteínas Portadoras/genética , Caspasa 3 , Caspasa 9 , Caspasas/genética , Grupo Citocromo c/metabolismo , Inhibidores Enzimáticos/farmacología , Precursores Enzimáticos/genética , Precursores Enzimáticos/metabolismo , Femenino , Vectores Genéticos , Humanos , Péptidos y Proteínas de Señalización Intracelular , Proteínas Mitocondriales/genética , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/genética , Proteínas/genética , Proteínas/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Proteínas Recombinantes de Fusión , Células Tumorales Cultivadas , Proteína Inhibidora de la Apoptosis Ligada a XRESUMEN
There is a need to enhance the efficacy of genetic prodrug activation therapy using herpes simplex virus thymidine kinase (tk) and ganciclovir (GCV) following disappointing results in early clinical trials. tk/GCV has been shown to lead to the activation of caspase-3, a potent executor of apoptosis. We demonstrate that co-expression of pro-caspase-3 with tk/GCV leads to enhanced cell death in ovarian carcinoma cells in vitro. Following transfection with recombinant adenoviral vectors encoding tk, GCV treatment leads to greater cell death in pro-caspase-3-expressing clones of SKOV3 and IGROV1 than control cells, as well as more rapid activation of caspase-3 and more rapid cleavage of PARP. Flow cytometry suggests that there is a greater degree of S-phase block in the pro-caspase-3-expressing clones than in control cells following treatment with tk/GCV. None of these effects is seen following transfection with a control adenovirus that does not encode tk. The increased cell death, early caspase-3 activation and PARP cleavage, and flow cytometric changes seen in pro-caspase-3-expressing cells can be partially inhibited by treatment with benzyloxycarbonyl-val-ala-asp fluoromethylketone, a synthetic caspase inhibitor. Our data suggest that co-expression of pro-caspase-3 may lead to a significant enhancement of the efficacy of tk/GCV therapy.
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Antivirales/farmacología , Apoptosis , Caspasas/metabolismo , Ganciclovir/farmacología , Neoplasias Ováricas/patología , Simplexvirus/enzimología , Timidina Quinasa/metabolismo , Células Tumorales Cultivadas/enzimología , Adenoviridae/genética , Clorometilcetonas de Aminoácidos/farmacología , Western Blotting , Caspasa 3 , Inhibidores de Caspasas , Supervivencia Celular/efectos de los fármacos , Inhibidores de Cisteína Proteinasa/farmacología , Cartilla de ADN/química , Resistencia a Antineoplásicos , Femenino , Citometría de Flujo , Terapia Genética/métodos , Vectores Genéticos , Proteínas Fluorescentes Verdes , Humanos , L-Lactato Deshidrogenasa/metabolismo , Proteínas Luminiscentes/metabolismo , Neoplasias Ováricas/enzimología , Poli(ADP-Ribosa) Polimerasas/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Simplexvirus/genética , TransfecciónRESUMEN
The ubiquitin-proteasome pathway plays a critical role in the degradation of several proteins involved in the cell cycle. Dysregulation of this pathway leads to inhibition of cellular proliferation and the induction of apoptosis. Ubiquitination and its downstream consequences have been investigated intensively as targets for the development of drugs for tumour therapy. Here we have investigated the mechanism of apoptosis induced by the proteasome inhibitors MG-132, lactacystin and calpain inhibitor I (ALLN), in the HEK 293 cell line and the ovarian cancer cell lines SKOV3 and OVCAR3. We have found strong caspase-3-like and caspase-6-like activation upon treatment of HEK 293 cells with MG-132. Using a tricistronic expression vector based on a tetracycline-responsive system we generated stable SKOV3 nd OVCAR3 cell lines with inducible expression of pro-caspase-3. Induction of pro-caspase-3 expression in normally growing cells does not induce apoptosis. However, in the presence of the proteasome inhibitors MG-132, lactacystin or ALLN we found that cells overexpressing pro-caspase-3 are rapidly targeted for apoptosis. Our results demonstrate that pro-caspase-3 can sensitise ovarian cancer cells to proteasome inhibitor-induced apoptosis, and a combination of these approaches might be exploited for therapy of ovarian and other cancers.
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Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Caspasas/biosíntesis , Inhibidores de Cisteína Proteinasa/farmacología , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/enzimología , Acetilcisteína/análogos & derivados , Acetilcisteína/farmacología , Apoptosis/fisiología , Caspasa 3 , Caspasas/genética , Caspasas/metabolismo , División Celular/efectos de los fármacos , Línea Celular Tumoral , Inducción Enzimática , Femenino , Citometría de Flujo , Fase G2/efectos de los fármacos , Glicoproteínas/farmacología , Humanos , Immunoblotting , Isoenzimas/biosíntesis , Isoenzimas/metabolismo , Leupeptinas/farmacología , Neoplasias Ováricas/genética , Neoplasias Ováricas/patología , TransfecciónRESUMEN
We have reported previously that among human prostate cancer cell lines LNCaP but not PC-3 cells undergo apoptosis after treatment with the protein kinase inhibitor staurosporine (STS). We have now further investigated this model to uncover the molecular mechanism causing resistance to STS-induced apoptosis in PC-3 cells. S-100 lysates of both cell lines showed biochemical changes typical of apoptosis after the addition of cytochrome c and dATP, suggesting that the postmitochondrial phase of apoptosis was intact. Upon addition of STS, the proapoptotic molecules Bax and Bad became predominantly mitochondrial in both cell lines. This, in turn, was followed by loss of mitochondrial transmembrane potential, translocation of cytochrome c to the cytosol, activation of caspase-9, -3, and -7, and cleavage of the apoptotic targets, DNA fragmentation factor and poly(ADP-ribose) polymerase, in LNCaP but not in PC-3 cells. Components of the mitochondrial permeability transition pore, adenine nucleotide transporter and voltage-dependent anion channel, were normally expressed in the correct subcellular fraction of both cell lines. Overexpression of the proapoptotic proteins Bax and Bad, fused to a green fluorescent protein but not of green fluorescent protein alone, induced apoptosis in >80% of PC-3 cells. These experiments suggested that a factor protecting the mitochondria of PC-3 cells mediates resistance to STS-induced apoptosis. A wide search among the antiapoptotic Bcl-2 family members was performed, and Bcl-X(L) was found to be overexpressed in PC-3 cells. Experiments down-regulating Bcl-X(L) expression by using the tyrosine kinase inhibitor genistein, sodium butyrate, or an antisense Bcl-X(L) oligonucleotide restored sensitivity to apoptosis in PC-3 cells. Thus, Bcl-X(L) overexpression is one of the mediators of resistance to STS-induced apoptosis in the prostate cancer cell line PC-3.
Asunto(s)
Apoptosis/efectos de los fármacos , Apoptosis/fisiología , Inhibidores Enzimáticos/farmacología , Neoplasias de la Próstata/patología , Proteínas Proto-Oncogénicas c-bcl-2/biosíntesis , Estaurosporina/farmacología , Proteínas Portadoras/biosíntesis , Proteínas Portadoras/genética , Regulación hacia Abajo/efectos de los fármacos , Resistencia a Antineoplásicos , Genisteína/farmacología , Humanos , Masculino , Mitocondrias/efectos de los fármacos , Mitocondrias/fisiología , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/metabolismo , Proteínas Proto-Oncogénicas/biosíntesis , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas c-bcl-2/genética , Transducción de Señal/fisiología , Fracciones Subcelulares/efectos de los fármacos , Fracciones Subcelulares/metabolismo , Células Tumorales Cultivadas , Proteína X Asociada a bcl-2 , Proteína Letal Asociada a bcl , Proteína bcl-XRESUMEN
Using adenoviral technology, we overexpressed the proapoptotic molecules pro-caspase-3, pro-caspase-7, and Bax to induce therapeutic apoptosis of prostate cancer cell lines growing in vitro and in vivo. Because overexpressed pro-caspase-3 did not undergo autocatalytic activation in any of the five prostate cancer cell lines evaluated, this strategy was unable to engage any component of the apoptotic pathway. Overexpressed pro-caspase-7 was proteolytically cleaved in LNCaP and LnCaP-Bcl-2 cells but not in PC-3, DU-145, or TsuPr(1) cells. Cleavage was associated with engagement of many components of the apoptotic pathway, including DEVDase activity, cleavage of intracellular caspase targets such as the DNA fragmentation factor and the proapoptotic Bid, release of cytochrome c from the mitochondria to the cytoplasm, and terminal deoxynucleotidyl transferase-mediated nick end labeling. No apoptosis was observed in the cells where caspase-7 did not undergo autocatalytic activation. Searching for an approach that would more reliably induce therapeutic apoptosis of prostate cancer cell lines, we used a binary adenoviral system to overexpress the proapoptotic molecule Bax. Bax was dramatically overexpressed and caused apoptosis of every cell line infected by engaging the mitochondrial pathway, including proteolytic cleavage and catalytic activation of the caspases, cleavage of caspase substrates, release of cytochrome c from the mitochondria, and DNA fragmentation. Furthermore, three injections of the Bax overexpression system into PC-3 cell tumors in nude mice in vivo caused a 25% regression in tumor size corresponding to a 90% reduction relative to continued tumor growth in animals that received injections with the control binary system expressing Lac-Z. These experiments show that adenovirus-mediated Bax overexpression is capable of inducing therapeutic programmed cell death in vitro and in vivo by activating the mitochondrial pathway of apoptosis. On the basis of these studies, we conclude that manipulation of Bax expression is an attractive new gene therapy approach for the treatment of prostate cancer.
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Apoptosis/fisiología , Terapia Genética/métodos , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/terapia , Proteínas Proto-Oncogénicas c-bcl-2 , Proteínas Proto-Oncogénicas/biosíntesis , Adenoviridae/genética , Animales , Caspasa 3 , Caspasa 7 , Caspasas/biosíntesis , Caspasas/genética , Precursores Enzimáticos/biosíntesis , Precursores Enzimáticos/genética , Vectores Genéticos/genética , Humanos , Masculino , Ratones , Ratones Desnudos , Mitocondrias/fisiología , Neoplasias de la Próstata/metabolismo , Proteínas Proto-Oncogénicas/genética , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto , Proteína X Asociada a bcl-2RESUMEN
PURPOSE: We hypothesized that expression/activity of critical components of the apoptotic pathway can be used to induce apoptosis of a human prostate cell line derived from benign prostatic hyperplasia (BPH) tissue. MATERIALS AND METHODS: We analyzed the apoptotic pathway in BPH cells treated with the powerful inducer of apoptosis, staurosporine (STS), and adenoviruses overexpressing caspase-3, -7, or the control gene lacZ. RESULTS: Twelve hours post-STS, most BPH cells were floating in the culture medium, TUNEL staining was widespread, and DEVDase activity (the catalytic activity of type II caspases) was increased. The pan-caspase inhibitor, Z-VAD-FMK, prevented STS-induced apoptosis. Based on these observations, we performed immunoblot analysis for the three known group II caspases (that is caspase-2, -3 and -7), but none of them was detected with three commercially available antibodies. Nevertheless, in view of the presence of increased DEVDase activity, we reasoned that a group II caspase must be a critical mediator of apoptosis in this model. If correct, we postulated that overexpression and activation of a type II caspase should cause apoptosis. To test this hypothesis, we coupled the cDNAs encoding caspase-3 and caspase-7 to adenoviral vectors and obtained constructs AvC3 and AvC7. Cells infected with AvC3 or AvC7 overexpressed the protein for caspase-3 or -7 within 24 to 48 hours. Caspase-3 overexpression did not cause apoptosis above that observed in cells receiving the control adenovirus expressing the lacZ cDNA (AvLac-Z). In contrast, caspase-7 overexpression induced massive apoptosis. BPH cells were then infected with increasing multiplicity of infection (MOI) of AvC7 and AvlacZ. A positive correlation was found between the amount of caspase-7 expressed and the level of DEVDase activity measured. AvC7 at MOIs of 25:1 and 50:1 induced apoptosis in about 50% of BPH cells at 72 hours post-infection. This effect was AvC7 specific, because the same MOIs of AvlacZ were not apoptogenic. CONCLUSIONS: Adenoviral-mediated overexpression of caspase-7 induces apoptosis of BPH-derived cells.
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Adenoviridae/genética , Apoptosis/fisiología , Caspasas/análisis , Hiperplasia Prostática/patología , Apoptosis/efectos de los fármacos , Caspasa 2 , Caspasa 3 , Caspasa 7 , Células Cultivadas , ADN Complementario , Inhibidores Enzimáticos/farmacología , Vectores Genéticos , Humanos , Immunoblotting , Etiquetado Corte-Fin in Situ , Operón Lac , Masculino , Estaurosporina/farmacologíaRESUMEN
OBJECTIVE: The 13C-urea breath test (13C-UBT) is a safe, noninvasive, and accurate test for the detection of Helicobacter pylori (H. pylori) infection in adults. The aim of this study was to evaluate sensitivity and specificity of 13C-UBT in children using different types of test meal, doses of 13C-urea and breath sampling intervals. As yet, a validated, standardized 13C-UBT protocol for children has not been formulated. METHODS: 13C-UBT was performed in 115 children and repeated within 3 days, modifying the test meal or the dose of 13C-urea. H. pylori status was assessed by histology and rapid urease test. 13C-UBT was performed using 100 mg or 50 mg of 13C-urea and a fatty test meal (100 FA; 50 FA), 50 mg of 13C-urea, and a carbohydrate test meal (50 CA). Breath samples were collected every 10 min for 60 min. RESULTS: The 13C-UBT in children was highly sensitive and specific with all three protocols used. The best combination of sensitivity (97.92%) and specificity (97.96%) was obtained with Protocol 50 FA at 30 min with a cut-off of 3.5 per mil. CONCLUSIONS: The 13C-UBT is an accurate test for the detection of H. pylori infection also in children. Administration of 50 mg of 13C-urea, a fatty test meal, and breath sampling at 30 min appears to be the most convenient protocol.
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Pruebas Respiratorias , Gastritis/diagnóstico , Infecciones por Helicobacter/diagnóstico , Helicobacter pylori , Urea/análisis , Adolescente , Adulto , Superficie Corporal , Niño , Preescolar , Relación Dosis-Respuesta a Droga , Femenino , Mucosa Gástrica/patología , Gastritis/patología , Gastroscopía , Infecciones por Helicobacter/patología , Humanos , Masculino , Estándares de Referencia , Sensibilidad y EspecificidadRESUMEN
BACKGROUND: The goal of this work was to identify mechanisms for the inability of metastatic prostate cancer cells to engage the apoptotic pathway following hormonal or cytotoxic therapy. METHODS: Genotypically diverse cell lines isolated from patients with metastatic disease were used. RESULTS: The LNCaP and TsuPr(1) lines exhibited quintessential apoptotic features in response to the pleiotropic apoptotic inducer staurosporine (STS): rapid cytochrome c translocation to the cytosol, proteolytic processing and catalytic activation of caspase-3 and -7, proteolytic inactivation of the death substrates DNA fragmentation factor (DFF) and poly-ADP-ribose polymerase (PARP), and TUNEL-positive polyfragmented nuclei. In contrast, DU-145 and PC-3 cells exhibited few, if any, of these features, while appearing necrotic by confocal microscopy. The presence of caspase-3 and -7 without proteolytic processing suggested that the apoptotic blockade was upstream of executioner caspases in these resistant cell lines. To identify the locus of this block, Western blot analysis of cytochrome c subcellular localization and of pro- and antiapoptotic Bcl-2 family members was performed, and suggested that heterogeneous expression of these proteins might be the underlying mechanism for apoptotic resistance to STS in these cell lines. Thus, the absence of the proapoptotic Bax in DU-145 cells indicated a mechanism for apoptotic resistance of these cells. Similarly, decreased Bax expression during STS treatment, coupled with overexpression of the antiapoptotic Bcl-x(L) and inability to translocate cytochrome c to the cytosol, provided a mechanism for the insensitivity of PC-3 cells. CONCLUSIONS: These observations suggest that activation of the apoptotic machinery in metastatic prostate cancer cell lines may be determined by expression levels of Bcl-2 family members, by the ability of cytochrome c to translocate to the cytosol, and by the ability of the caspase pathway to react in response to activation of the mitochondrial phase.
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Apoptosis/efectos de los fármacos , Caspasas/metabolismo , Neoplasias de la Próstata/patología , Proteínas Proto-Oncogénicas c-bcl-2/biosíntesis , Proteínas Proto-Oncogénicas/biosíntesis , Estaurosporina/farmacología , Proteínas Reguladoras de la Apoptosis , Transporte Biológico , Caspasa 3 , Caspasa 7 , Catálisis , Supervivencia Celular , Grupo Citocromo c/metabolismo , Citosol/metabolismo , Fragmentación del ADN , Activación Enzimática , Inhibidores Enzimáticos/farmacología , Humanos , Etiquetado Corte-Fin in Situ , Membranas Intracelulares/fisiología , Masculino , Mitocondrias/fisiología , Necrosis , Poli(ADP-Ribosa) Polimerasas/metabolismo , Neoplasias de la Próstata/enzimología , Neoplasias de la Próstata/metabolismo , Proteínas/metabolismo , Inhibidores de Topoisomerasa II , Células Tumorales Cultivadas , Proteína X Asociada a bcl-2RESUMEN
The aim of the study was to identify immediate clinical and/or laboratory findings able to differentiate bacterial from viral etiology of acute gastroenteritis in pediatric patients. We studied 52 children, aged between 5 months and 12 years, consecutively admitted to hospital with acute diarrhoea lasting less than 5 days. All the patients were divided into 4 groups according to etiologic agent, subsequently demonstrated by culture: salmonellae (group A), rotavirus (group B); combined salmonellae and rotavirus (group C) and no pathogen (group D). The contemporary presence of fever > 39 degrees C, number of daily liquid stools > 6, presence of bloody diarrhoea, positivity of C-reactive protein and hyponatremia (< 135 mEq/l) allowed to recognize the etiology (viral or bacterial) before results of culture (sensitivity was 71% and specificity was 97%). In particular, hyponatremia resulted significantly lower in group A and C than in group B and D. We concluded that hyponatremia can be considered a marker for acute gastroenteritis caused by salmonellae.
Asunto(s)
Gastroenteritis/microbiología , Enfermedad Aguda , Niño , Preescolar , Diagnóstico Diferencial , Gastroenteritis/diagnóstico , Gastroenteritis/virología , Humanos , LactanteRESUMEN
The aim of this case-control study, was to estimate clinical effects, safety and parents' assessment of Diosmectite, in acute infantile diarrhoea. Thirty-five children aged 0-5 years, with acute diarrhoea from at least 5 days received alternatively oral rehydration solution (ORS) and Diosmectite (3 g/day for 3 days in children aged under 3 years and 6 g/day for 3 days in children aged over 3 years) (16 cases) or ORS only (19 cases). At discharge, parents' opinion concerning satisfaction for treatment received was evaluated through a questionnaire. Differences in the amount of liquid intake, weigh recovery, resolution of fever, resolution of vomiting and number of loose stools in the first 48 hours of hospitalization were not significant. Diosmectite was well tolerated and no major side effects were found. Parents' satisfaction for therapy resulted higher in the treated group than in the control group, even if differences were not significant. Treatment with ORS and Diosmectite allowed to shorten the mean duration of hospitalization by 0.4 days/children in the treatment group compared to the control group. Further studies with more cases and with higher does of the drug are necessary to confirm our results.