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1.
J Cell Mol Med ; 19(2): 327-39, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25444175

RESUMEN

Toll-like receptors (TLRs) are a family of highly conserved transmembrane proteins expressed in epithelial and immune cells that recognize pathogen associated molecular patterns. Besides their role in immune response against infections, numerous studies have shown an important role of different TLRs in cancer, indicating these receptors as potential targets for cancer therapy. We previously demonstrated that the activation of TLR3 by the synthetic double-stranded RNA analogue poly I:C induces apoptosis of androgen-sensitive prostate cancer (PCa) LNCaP cells and, much less efficiently, of the more aggressive PC3 cell line. Therefore, in this study we selected LNCaP cells to investigate the mechanism of TLR3-mediated apoptosis and the in vivo efficacy of poly I:C-based therapy. We show that interferon regulatory factor-3 (IRF-3) signalling plays an essential role in TLR3-mediated apoptosis in LNCaP cells through the activation of the intrinsic and extrinsic apoptotic pathways. Interestingly, hardly any apoptosis was induced by poly I:C in normal prostate epithelial cells RWPE-1. We also demonstrate for the first time the direct anticancer effect of poly I:C as a single therapeutic agent in a well-established human androgen-sensitive PCa xenograft model, by showing that tumour growth is highly impaired in poly I:C-treated immunodeficient mice. Immunohistochemical analysis of PCa xenografts highlights the antitumour role of poly I:C in vivo both on cancer cells and, indirectly, on endothelial cells. Notably, we show the presence of TLR3 and IRF-3 in both human normal and PCa clinical samples, potentially envisaging poly I:C-based therapy for PCa.


Asunto(s)
Andrógenos/farmacología , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Factor 3 Regulador del Interferón/metabolismo , Próstata/efectos de los fármacos , Próstata/metabolismo , Animales , Apoptosis/fisiología , Línea Celular , Línea Celular Tumoral , Proliferación Celular/fisiología , Humanos , Masculino , Ratones , Ratones Endogámicos NOD
2.
Biol Reprod ; 90(3): 53, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24478388

RESUMEN

FOXP3(+) regulatory T cells (Tregs) are central to the maintenance of immunological homeostasis and tolerance. It has long been known that Sertoli cells are endowed with immune suppressive properties; however, the underlying mechanisms as well as the effective nature and role of soluble factors secreted by Sertoli cells have not been fully elucidated as yet. We hypothesized that conditioned medium from primary mouse Sertoli cells (SCCM) may be able and sufficient to induce Tregs. By culturing CD4(+)CD25(-)EGFP(-) T splenocytes purified from FOXP3-EGFP knock-in mice in SCCM, here we show, by flow cytometry and suppression assay, the conversion of peripheral CD4(+)FOXP3(-) T cells into functional CD4(+)FOXP3(+) Tregs. We also demonstrate that the Notch/Jagged1 axis is involved in regulating the de novo generation of Tregs although this process is transforming growth factor-beta1 (TGF-B) dependent. In particular, we identified by Western blot analysis a soluble form of JAGGED1 (JAG1) in SCCM that significantly influences the induction of Tregs, as demonstrated by performing the conversion assay in presence of a JAG1-specific neutralizing antibody. In addition, we show that SCCM modulates the Notch pathway in converted Tregs by triggering the recruitment of the Notch-specific transcription factor CSL/RBP-Jk to the Foxp3 promoter and by inducing the Notch target gene Hey1, as shown by chromatin immunoprecipitation assay and by real time-RT-PCR experiments, respectively. Overall, these results contribute to a better understanding of the molecular mechanisms involved in Sertoli cell-mediated immune tolerance and provide a novel approach to generate ex vivo functional Tregs for therapeutic purpose.


Asunto(s)
Proteínas de Unión al Calcio/fisiología , Péptidos y Proteínas de Señalización Intercelular/fisiología , Proteínas de la Membrana/fisiología , Receptores Notch/fisiología , Células de Sertoli/fisiología , Linfocitos T Reguladores/fisiología , Animales , Western Blotting , Antígenos CD4/biosíntesis , Antígenos CD4/genética , Proteínas de Unión al Calcio/genética , Proteínas de Ciclo Celular/genética , Inmunoprecipitación de Cromatina , Citometría de Flujo , Factores de Transcripción Forkhead/fisiología , Péptidos y Proteínas de Señalización Intercelular/genética , Proteína Jagged-1 , Masculino , Proteínas de la Membrana/genética , Ratones , Cultivo Primario de Células , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptores Notch/genética , Proteínas Serrate-Jagged , Supresión Genética , Transfección , Factor de Crecimiento Transformador beta/fisiología
3.
Apoptosis ; 17(11): 1210-22, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22923157

RESUMEN

TNF-alpha levels in prostate cancer correlate with the extent of disease and are significantly elevated in the metastatic stage. TNF receptor superfamily controls two distinct signalling cascades, leading to opposite effects, i.e. apoptosis and survival; in prostate cancer TNF-alpha-mediated signalling induces cell survival and resistance to therapy. The apoptosis of prostate epithelial cancer cells LNCaP and PC3 was investigated upon treatment with the autophagy inhibitor 3-methyladenine and the autophagy inducer rapamycin, in combination with TNF-alpha. Cells were exposed to these molecules for 18, 24 and 48 h. Autophagy was assessed via LC3 Western blot analysis; propidium iodide and TUNEL stainings followed by flow cytometry or caspase-8 and caspase-3 activation assays were performed to evaluate apoptosis. TNF-alpha-induced apoptosis was potentiated by 3-methyladenine in the androgen-responsive LNCaP cells, whereas no effect was observed in the androgen-insensitive PC3 cells. Interestingly such pro-apoptosis effect in LNCaP cells was associated with reduced c-Flip levels through proteasomal degradation via increased reactive oxygen species production and p38 activation; such c-Flip reduction was reversed in the presence of either the proteasome inhibitor MG132 or the reactive oxygen species scavenger N-acetyl-cysteine. Conversely in PC3 but not in LNCaP cells, rapamycin stimulated TNF-alpha-dependent apoptosis; such effect was associated with reduced c-Flip promoter activity and FoxO3a activation. We conclude that TNF-alpha-induced apoptosis may be potentiated, in prostate cancer epithelial cells, through autophagy modulators. Increased sensitivity to TNF-alpha-dependent apoptosis correlates with reduced c-Flip levels which are consequent to a post-transcriptional and a transcriptional mechanism in LNCaP and PC3 cells respectively.


Asunto(s)
Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Células Epiteliales/patología , Neoplasias de la Próstata/patología , Factor de Necrosis Tumoral alfa/farmacología , Adenina/análogos & derivados , Western Blotting , Proteína Reguladora de Apoptosis Similar a CASP8 y FADD/genética , Proteína Reguladora de Apoptosis Similar a CASP8 y FADD/metabolismo , Línea Celular Tumoral , Ensayos de Selección de Medicamentos Antitumorales , Activación Enzimática/efectos de los fármacos , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Proteína Forkhead Box O3 , Factores de Transcripción Forkhead/metabolismo , Humanos , Masculino , Proteínas Asociadas a Microtúbulos/metabolismo , Regiones Promotoras Genéticas/genética , Neoplasias de la Próstata/enzimología , Complejo de la Endopetidasa Proteasomal/metabolismo , Inhibidores de Proteasoma/farmacología , Proteolisis/efectos de los fármacos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Sirolimus/farmacología , Transcripción Genética/efectos de los fármacos , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
4.
Hum Reprod ; 27(8): 2267-76, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22647452

RESUMEN

BACKGROUND: Clusterin, a heterodimeric glycoprotein found at several sites in the human male reproductive tract, could be a marker of morphologically abnormal spermatozoa, while TUNEL positivity indicates DNA fragmentation. Metabolic disorders such as diabetes mellitus and obesity may compromise sperm quality and fertility of men; however, little evidence specifically links hypertension with the impairment of male reproductive function. METHODS: By flow cytometric, immunofluorescence (TUNEL assay and clusterin immunolabeling) and immunohistochemical (peroxidase-streptavidin method) analyses, we have compared both clusterin- and TUNEL labeling in ejaculated spermatozoa from healthy normotensive donors and hypertensive subjects with the purpose to reveal possible differences between the two conditions. RESULTS: Data analysis from the normotensive (n=25) and hypertensive subjects (n=25) demonstrate a significant correlation between high levels of clusterin immunolabeling and the presence of sperm DNA damage, which is often associated with abnormal morphology. In the normotensive subjects, a low percentage (15.3±4.5) of spermatozoa positive for high levels of clusterin was detected; however, this percentage significantly increased (30.9±13.0) (P<0.01) in hypertensive subjects. Standard semen evaluations does not reveal any significant differences between the two groups of subjects, except for a reduced forward motility and lower sperm vitality in the hypertensive subjects. CONCLUSIONS: This pilot study strongly suggests a relationship between hypertension and markers indicative of poor sperm quality. In hypertensive subjects, high levels of clusterin immunolabeling identified a consistent fraction of ejaculated spermatozoa carrying both DNA fragmentation and strong morphological alterations, which was not correlated with age or with sperm cell mortality. The alternative possibility that sperm damage observed is due to adverse effects of anti-hypertensive drugs does not find support in the literature nor in the drug data sheets. The relationship observed between hypertension and human semen represents a novel and possibly relevant information to be considered in the study of male fertility.


Asunto(s)
Clusterina/química , Daño del ADN , Hipertensión/metabolismo , Espermatozoides/metabolismo , Adulto , Estudios de Casos y Controles , Estudios de Cohortes , Fragmentación del ADN , Citometría de Flujo/métodos , Glicoproteínas/química , Humanos , Hipertensión/patología , Etiquetado Corte-Fin in Situ , Masculino , Microscopía Fluorescente/métodos , Persona de Mediana Edad , Análisis de Regresión , Semen/metabolismo , Espermatozoides/patología
5.
Comput Methods Programs Biomed ; 219: 106763, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35349908

RESUMEN

BACKGROUND AND OBJECTIVE: Many methodologies have been proposed for the control of total intravenous anesthesia in general surgery, as this yields a reduced stress for the anesthesiologist and an increased safety for the patient. The objective of this work is to design a PID-based control system for the regulation of the depth of hypnosis by propofol and remifentanil coadministration that takes into account the clinical practice. METHODS: With respect to a standard PID control system, additional functionalities have been implemented in order to consider specific requirements related to the clinical practice. In particular, suitable boluses are determined and used in the induction phase and a nonzero baseline infusion is used in the maintenance phase when the predicted effect-site concentration drops below a safety threshold. RESULTS: The modified controller has been experimentally assessed on a group of 10 patients receiving general anesthesia for elective plastic surgery. The control system has been able to induce and maintain adequate anesthesia without any manual intervention from the anesthesiologist. CONCLUSIONS: Results confirm the effectiveness of the overall design approach and, in particular, highlight that the new version of the control system, with respect to a standard PID controller, provides significant advantages from a clinical standpoint.


Asunto(s)
Hipnosis , Propofol , Anestesia General , Anestésicos Intravenosos , Humanos , Remifentanilo
6.
Cancer Biol Med ; 2021 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-34018387

RESUMEN

OBJECTIVE: Bone metastasis is a clinically important outcome of prostate carcinoma (PC). We focused on the phenotypic and functional characterization of a particularly aggressive phenotype within the androgen-independent bone metastasis-derived PC3 cell line. These cells, originated from the spontaneous conversion of a CD44-negative subpopulation, stably express the CD44v8-10 isoform (CD44v8-10pos) and display stem cell-like features and a marked invasive phenotype in vitro that is lost upon CD44v8-10 silencing. METHODS: Flow cytometry, enzyme-linked immunoassay, immunofluorescence, and Western blot were used for phenotypic and immunologic characterization. Real-time quantitative polymerase chain reaction and functional assays were used to assess osteomimicry. RESULTS: Analysis of epithelial-mesenchymal transition markers showed that CD44v8-10pos PC3 cells surprisingly display epithelial phenotype and can undergo osteomimicry, acquiring bone cell phenotypic and behavioral traits. Use of specific siRNA evidenced the ability of CD44v8-10 variant to confer osteomimetic features, hence the potential to form bone-specific metastasis. Moreover, the ability of tumors to activate immunosuppressive mechanisms which counteract effective immune responses is a sign of the aggressiveness of a tumor. Here we report that CD44v8-10pos cells express programmed death ligand 1, a negative regulator of anticancer immunity, and secrete exceptionally high amounts of interleukin-6, favoring osteoclastogenesis and immunosuppression in bone microenvironment. Notably, we identified a novel pathway activated by CD44v8-10, involving tafazzin (TAZ) and likely the Wnt/TAZ axis, known to play a role in upregulating osteomimetic genes. CONCLUSIONS: CD44v8-10 could represent a marker of a more aggressive bone metastatic PC population exerting a driver role in osteomimicry in bone. A novel link between TAZ and CD44v8-10 is also shown.

7.
BMC Cancer ; 10: 363, 2010 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-20615237

RESUMEN

BACKGROUND: The majority of cancer patients experience dramatic weight loss, due to cachexia and consisting of skeletal muscle and fat tissue wasting. Cachexia is a negative prognostic factor, interferes with therapy and worsens the patients' quality of life by affecting muscle function. Mice bearing ectopically-implanted C26 colon carcinoma are widely used as an experimental model of cancer cachexia. As part of the search for novel clinical and basic research applications for this experimental model, we characterized novel cellular and molecular features of C26-bearing mice. METHODS: A fragment of C26 tumor was subcutaneously grafted in isogenic BALB/c mice. The mass growth and proliferation rate of the tumor were analyzed. Histological and cytofluorometric analyses were used to assess cell death, ploidy and differentiation of the tumor cells. The main features of skeletal muscle atrophy, which were highlighted by immunohistochemical and electron microscopy analyses, correlated with biochemical alterations. Muscle force and resistance to fatigue were measured and analyzed as major functional deficits of the cachectic musculature. RESULTS: We found that the C26 tumor, ectopically implanted in mice, is an undifferentiated carcinoma, which should be referred to as such and not as adenocarcinoma, a common misconception. The C26 tumor displays aneuploidy and histological features typical of transformed cells, incorporates BrdU and induces severe weight loss in the host, which is largely caused by muscle wasting. The latter appears to be due to proteasome-mediated protein degradation, which disrupts the sarcomeric structure and muscle fiber-extracellular matrix interactions. A pivotal functional deficit of cachectic muscle consists in increased fatigability, while the reported loss of tetanic force is not statistically significant following normalization for decreased muscle fiber size. CONCLUSIONS: We conclude, on the basis of the definition of cachexia, that ectopically-implanted C26 carcinoma represents a well standardized experimental model for research on cancer cachexia. We wish to point out that scientists using the C26 model to study cancer and those using the same model to study cachexia may be unaware of each other's works because they use different keywords; we present strategies to eliminate this gap and discuss the benefits of such an exchange of knowledge.


Asunto(s)
Adenocarcinoma/complicaciones , Caquexia/etiología , Neoplasias del Colon/complicaciones , Neoplasias Pulmonares/complicaciones , Músculo Esquelético/patología , Atrofia Muscular/etiología , Adenocarcinoma/patología , Animales , Apoptosis , Western Blotting , Caquexia/patología , Proliferación Celular , Neoplasias del Colon/patología , Modelos Animales de Enfermedad , Citometría de Flujo , Técnicas para Inmunoenzimas , Neoplasias Pulmonares/secundario , Ratones , Ratones Endogámicos BALB C , Atrofia Muscular/patología , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
8.
Anticancer Res ; 40(10): 5379-5391, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32988857

RESUMEN

BACKGROUND/AIM: Hypoxia-inducible factor 1 (HIF1) inhibitors have been proposed as therapeutic agents for several tumor types. HIF1α is induced by hypoxia and by pathogens in normoxia through toll-like receptors (TLRs). The TLR3 activator polyinosinic:polycytidylic acid [poly(I:C)] induces apoptosis in various types of cancer but not in the most aggressive breast cancer cell lines. We hypothesized that the failure of TLR3 stimulation to induce apoptosis in these cells might be due to an elevated HIF1α level and this link might be exploited. MATERIALS AND METHODS: Poly(I:C)-induced signaling pathway and expression of HIF1α and HIF1α targets were studied in MDA MB-231 and MCF-7 breast cancer cell lines by western blot. Flow cytometry was used for apoptotic responses and vasculogenic mimicry as bioassay. RESULTS: Poly(I:C) increased expression of HIF1α and its targets BCL2 apoptosis regulator and c-MYC. Moreover, using pharmacological or genetic HIF1 inhibition, reduction of poly(I:C)-induced expression of HIF1α was paralleled by lowering of c-MYC and increased sensitivity to poly(I:C)-induced apoptosis, demonstrating the crucial role of this factor. We provide the first evidence in breast cancer cells that TLR3 stimulation induces HIF1α-dependent vasculogenic mimicry. By using specific inhibitors, we identified a signaling cascade upstream of HIF1α induction. CONCLUSION: Combined treatment with poly(I:C) and HIF1 inhibitors deserves consideration as an effective strategy in breast cancer therapy.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Poli I-C/farmacología , Receptor Toll-Like 3/genética , Apoptosis/efectos de los fármacos , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Proliferación Celular/efectos de los fármacos , Femenino , Citometría de Flujo , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Células MCF-7 , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas c-myc/genética , Transducción de Señal/efectos de los fármacos , Receptor Toll-Like 3/agonistas
9.
Front Immunol ; 11: 350, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32231663

RESUMEN

Atherosclerosis is a progressive vascular disease representing the primary cause of morbidity and mortality in developed countries. Formerly, atherosclerosis was considered as a mere passive accumulation of lipids in blood vessels. However, it is now clear that atherosclerosis is a complex and multifactorial disease, in which the involvement of immune cells and inflammation play a key role. A variety of studies have shown that autophagy-a cellular catalytic mechanism able to remove injured cytoplasmic components in response to cellular stress-may be proatherogenic. So far, in this context, its role has been investigated in smooth muscle cells, macrophages, and endothelial cells, while the function of this catabolic protective process in lymphocyte functionality has been overlooked. The few studies carried out so far, however, suggested that autophagy modulation in lymphocyte subsets may be functionally related to plaque formation and development. Therefore, in this research, we aimed at better clarifying the role of lymphocyte subsets, mainly regulatory T cells (Tregs), in human atherosclerotic plaques and in animal models of atherosclerosis investigating the contribution of autophagy on immune cell homeostasis. Here, we investigate basal autophagy in a mouse model of atherosclerosis, apolipoprotein E (ApoE)-knockout (KO) mice, and we analyze the role of autophagy in driving Tregs polarization. We observed defective maturation of Tregs from ApoE-KO mice in response to tumor growth factor-ß (TGFß). TGFß is a well-known autophagy inducer, and Tregs maturation defects in ApoE-KO mice seem to be related to autophagy impairment. In this work, we propose that autophagy underlies Tregs maturation, advocating that the study of this process in atherosclerosis may open new therapeutic strategies.


Asunto(s)
Aterosclerosis/inmunología , Autofagia/fisiología , Linfocitos T Reguladores/citología , Aldosterona/farmacología , Animales , Apolipoproteínas E/fisiología , Aterosclerosis/fisiopatología , Aterosclerosis/terapia , Autofagia/efectos de los fármacos , Diferenciación Celular , Polaridad Celular , Modelos Animales de Enfermedad , Factores de Transcripción Forkhead/metabolismo , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Placa Aterosclerótica/inmunología , Linfocitos T Reguladores/fisiología , Factor de Crecimiento Transformador beta/farmacología
10.
Carcinogenesis ; 29(7): 1334-42, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18566014

RESUMEN

Toll-like receptors (TLRs) are known to play a key role in the innate immune system particularly in inflammatory response against invading pathogens. Recent reports strongly indicate that they play important roles in cancer cells. Prostate cancer represents one of the most common cancer for which no cure is available once metastatic and androgen refractory. Since TLR3 has been recently suggested as a possible therapeutic target in some cancer cell lines, we studied TLR3 expression and functionality in two human prostate cancer cell lines, LNCaP and PC3. We report that both cell lines express TLR3 and that the TLR3 agonist poly (I:C) activates mitogen-activated protein kinases and induces inhibition of proliferation as well as caspase-dependent apoptosis. By using pharmacological and genetic approaches, we demonstrate the involvement of TLR3 in poly (I:C)-induced effects. We also show that a novel interferon-independent pathway involving protein kinase C (PKC)-alpha activation, upstream of p38 and c-jun N-terminal kinase, is responsible for poly (I:C) pro-apoptotic effects on LNCaP cells. To our knowledge, this is the first report describing a role of PKC-alpha in poly (I:C)-mediated apoptosis. The comprehension of the mechanisms underlying TLR3-mediated apoptosis can contribute tools to develop new agonists useful for the treatment of prostate cancer.


Asunto(s)
Apoptosis/fisiología , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Proteína Quinasa C-alfa/metabolismo , Receptor Toll-Like 3/metabolismo , Apoptosis/efectos de los fármacos , Procesos de Crecimiento Celular/efectos de los fármacos , Procesos de Crecimiento Celular/fisiología , Línea Celular Tumoral , Activación Enzimática , Humanos , Interferón beta/metabolismo , MAP Quinasa Quinasa 4/metabolismo , Masculino , Proteínas Quinasas Activadas por Mitógenos/antagonistas & inhibidores , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Fosforilación , Poli I-C/farmacología , Neoplasias de la Próstata/enzimología , Neoplasias de la Próstata/genética , Receptores Androgénicos/biosíntesis , Receptores Androgénicos/genética , Receptor Toll-Like 3/antagonistas & inhibidores , Transfección , Proteína p53 Supresora de Tumor/biosíntesis , Proteína p53 Supresora de Tumor/genética , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
11.
Neurol Res ; 30(2): 160-9, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18397608

RESUMEN

OBJECTIVE: Cachexia, a debilitating syndrome characterized by skeletal muscle wasting, is associated to many chronic diseases and diminishes the quality of life and survival of patients. Tumor-derived factors and proinflammatory cytokines, including TNF-alpha, IL-6 and IL-1 beta, mediate cachexia. In response to elevated cytokine levels, increased proteasome-mediated proteolysis and auto-phagocytosis result in muscle wasting. The histologic features of muscle cachexia are not fully elucidated. Therefore, we analysed alterations of different cell populations in cachectic muscle. METHODS: By immunohistochemical and cytological approaches, we characterized changes in the abundance of cellular populations in the musculature of a murine model of cancer cachexia (C26-bearing mice). RESULTS: Cachectic muscle displayed a decreased DNA content proportional to muscle mass wastage. A decrease in the number of nuclei occurred in the muscular but not in the stromal compartment. Cachectic muscle showed: mild modulation of myeloperoxidase activity, a neutrophil marker; reduction of macrophages in the endomysium; decrease in CD3(+) lymphocyte number. Conversely, a statistically significant enrichment in Sca-1(+) CD45(+) hematopoietic stem cells (HSCs) occurred in cachectic muscle. DISCUSSION: The elevated levels of cytokines which characterize cachexia may represent a trigger for inflammatory cell activation. However, we find that in cachexia, inflammatory cells in muscle are not increased while muscle tissue nuclei decline. Our data suggest that the inflammatory cell-mediated stress is not an etiologic component of muscle wasting in cachexia. The relative increase in HSCs in cachectic skeletal muscle suggests an attempt to maintain muscle homeostasis by recruitment and/or activation of stem cells.


Asunto(s)
Caquexia/patología , Células Madre Hematopoyéticas/fisiología , Músculo Esquelético/patología , Animales , Antígenos Ly/metabolismo , Peso Corporal , Caquexia/complicaciones , Caquexia/etiología , ADN/metabolismo , Modelos Animales de Enfermedad , Femenino , Citometría de Flujo/métodos , Regulación Neoplásica de la Expresión Génica/fisiología , Antígenos Comunes de Leucocito/metabolismo , Linfocitos/patología , Macrófagos/patología , Proteínas de la Membrana/metabolismo , Ratones , Ratones Endogámicos BALB C , Atrofia Muscular/etiología , NADP Transhidrogenasas/metabolismo , Neoplasias/complicaciones , Peroxidasa/metabolismo , Factores de Tiempo
12.
Oncotarget ; 9(56): 30905-30918, 2018 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-30112117

RESUMEN

In human prostate cancer (PCa), the neuroendocrine cells, expressing the prostate cancer stem cell (CSC) marker CD44, may be resistant to androgen ablation and promote tumor recurrence. During the study of heterogeneity of the highly aggressive neuroendocrine PCa cell lines PC3 and DU-145, we isolated and expanded in vitro a minor subpopulation of very small cells lacking CD44 (CD44neg). Unexpectedly, these sorted CD44neg cells rapidly and spontaneously converted to a stable CD44high phenotype specifically expressing the CD44v8-10 isoform which the sorted CD44high subpopulation failed to express. Surprisingly and potentially interesting, in these cells expression of CD44v8-10 was found to be induced in stem cell medium. CD44 variant isoforms are known to be more expressed in CSC and metastatic cells than CD44 standard isoform. In agreement, functional analysis of the two sorted and cultured subpopulations has shown that the CD44v8-10pos PC3 cells, resulting from the conversion of the CD44neg subpopulation, were more invasive in vitro and had a higher clonogenic potential than the sorted CD44high cells, in that they produced mainly holoclones, known to be enriched in stem-like cells. Of interest, the CD44v8-10 is more expressed in human PCa biopsies than in normal gland. The discovery of CD44v8-10pos cells with stem-like and invasive features, derived from a minoritarian CD44neg cell population in PCa, alerts on the high plasticity of stem-like markers and urges for prudency on the approaches to targeting the putative CSC.

13.
Cancer Res ; 65(4): 1505-13, 2005 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-15735039

RESUMEN

Ex vivo amplification of human hematopoietic stem cells (HSC) without loss of their self-renewing potential represents an important target for transplantation, gene and cellular therapies. Valproic acid is a safe and widely used neurologic agent that acts as a potent inhibitor of histone deacetylase activities. Here, we show that valproic acid addition to liquid cultures of human CD34+ cells isolated from cord blood, mobilized peripheral blood, and bone marrow strongly enhances the ex vivo expansion potential of different cytokine cocktails as shown by morphologic, cytochemical, immunophenotypical, clonogenic, and gene expression analyses. Notably, valproic acid highly preserves the CD34 positivity after 1 week (range, 40-89%) or 3 weeks (range, 21-52%) amplification cultures with two (Flt3L + thrombopoietin) or four cytokines (Flt3L + thrombopoietin + stem cell factor + interleukin 3). Moreover, valproic acid treatment increases histone H4 acetylation levels at specific regulatory sites on HOXB4, a transcription factor gene with a key role in the regulation of HSC self-renewal and AC133, a recognized marker gene for stem cell populations. Overall, our results relate the changes induced by valproic acid on chromatin accessibility with the enhancement of the cytokine effect on the maintenance and expansion of a primitive hematopoietic stem cell population. These findings underscore the potentiality of novel epigenetic approaches to modify HSC fate in vitro.


Asunto(s)
Citocinas/farmacología , Inhibidores Enzimáticos/farmacología , Células Madre Hematopoyéticas/efectos de los fármacos , Inhibidores de Histona Desacetilasas , Ácido Valproico/farmacología , Antígeno AC133 , Acetilación/efectos de los fármacos , Antígenos CD , Antígenos CD34/biosíntesis , Apoptosis/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Procesos de Crecimiento Celular/efectos de los fármacos , Cromatina/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Glicoproteínas/metabolismo , Células Madre Hematopoyéticas/citología , Células Madre Hematopoyéticas/enzimología , Células Madre Hematopoyéticas/inmunología , Proteínas de Homeodominio/metabolismo , Humanos , Péptidos/metabolismo , Trombopoyetina/farmacología , Factores de Transcripción/metabolismo
14.
ISA Trans ; 66: 344-361, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27988040

RESUMEN

In this paper a set of optimally balanced tuning rules for fractional-order proportional-integral-derivative controllers is proposed. The control problem of minimizing at once the integrated absolute error for both the set-point and the load disturbance responses is addressed. The control problem is stated as a multi-objective optimization problem where a first-order-plus-dead-time process model subject to a robustness, maximum sensitivity based, constraint has been considered. A set of Pareto optimal solutions is obtained for different normalized dead times and then the optimal balance between the competing objectives is obtained by choosing the Nash solution among the Pareto-optimal ones. A curve fitting procedure has then been applied in order to generate suitable tuning rules. Several simulation results show the effectiveness of the proposed approach.

15.
Comput Methods Programs Biomed ; 144: 21-35, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28495004

RESUMEN

BACKGROUND AND OBJECTIVE: This paper addresses the use of proportional-integral-derivative controllers for regulating the depth of hypnosis in anesthesia by using propofol administration and the bispectral index as a controlled variable. In fact, introducing an automatic control system might provide significant benefits for the patient in reducing the risk for under- and over-dosing. METHODS: In this study, the controller parameters are obtained through genetic algorithms by solving a min-max optimization problem. A set of 12 patient models representative of a large population variance is used to test controller robustness. The worst-case performance in the considered population is minimized considering two different scenarios: the induction case and the maintenance case. RESULTS: Our results indicate that including a gain scheduling strategy enables optimal performance for induction and maintenance phases, separately. Using a single tuning to address both tasks may results in a loss of performance up to 102% in the induction phase and up to 31% in the maintenance phase. Further on, it is shown that a suitably designed low-pass filter on the controller output can handle the trade-off between the performance and the noise effect in the control variable. CONCLUSIONS: Optimally tuned PID controllers provide a fast induction time with an acceptable overshoot and a satisfactory disturbance rejection performance during maintenance. These features make them a very good tool for comparison when other control algorithms are developed.


Asunto(s)
Anestesia/métodos , Hipnosis Anestésica , Hipnóticos y Sedantes/administración & dosificación , Propofol/administración & dosificación , Algoritmos , Humanos , Modelos Teóricos
16.
Comput Methods Programs Biomed ; 147: 63-83, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28734531

RESUMEN

BACKGROUND AND OBJECTIVE: In this paper, we propose the use of an event-based control strategy for the closed-loop control of the depth of hypnosis in anesthesia by using propofol administration and the bispectral index as a controlled variable. METHODS: A new event generator with high noise-filtering properties is employed in addition to a PIDPlus controller. The tuning of the parameters is performed off-line by using genetic algorithms by considering a given data set of patients. RESULTS: The effectiveness and robustness of the method is verified in simulation by implementing a Monte Carlo method to address the intra-patient and inter-patient variability. A comparison with a standard PID control structure shows that the event-based control system achieves a reduction of the total variation of the manipulated variable of 93% in the induction phase and of 95% in the maintenance phase. CONCLUSIONS: The use of event based automatic control in anesthesia yields a fast induction phase with bounded overshoot and an acceptable disturbance rejection. A comparison with a standard PID control structure shows that the technique effectively mimics the behavior of the anesthesiologist by providing a significant decrement of the total variation of the manipulated variable.


Asunto(s)
Anestesia/métodos , Hipnosis , Propofol/administración & dosificación , Algoritmos , Anestésicos Intravenosos , Humanos , Método de Montecarlo
17.
Cancer Lett ; 406: 93-104, 2017 10 10.
Artículo en Inglés | MEDLINE | ID: mdl-28797843

RESUMEN

Poor prognosis in lung cancer has been attributed to the presence of lung cancer stem cells (CSCs) which resist chemotherapy and cause disease recurrence. Hence, the strong need to identify mechanisms of chemoresistance and to develop new combination therapies. We have previously shown that Stearoyl-CoA-desaturase 1 (SCD1), the enzyme responsible for the conversion of saturated to monounsaturated fatty acids is upregulated in 3D lung cancer spheroids and is an upstream activator of key proliferation pathways ß-catenin and YAP/TAZ. Here we first show that SCD1 expression, either alone or in combination with a variety of CSCs markers, correlates with poor prognosis in adenocarcinoma (ADC) of the lung. Treatment of lung ADC cell cultures with cisplatin enhances the formation of larger 3D tumor spheroids and upregulates CSCs markers. In contrast, co-treatment with cisplatin and the SCD1 inhibitor MF-438 reverts upregulation of CSCs markers, strongly synergizes in the inhibition of 3D spheroids formation and induces CSCs apoptosis. Mechanistically, SCD1 inhibition activates endoplasmic reticulum stress response and enhances autophagy. These data all together support the use of combination therapy with SCD1 inhibitors to achieve better control of lung cancer.


Asunto(s)
Cisplatino/farmacología , Resistencia a Antineoplásicos/efectos de los fármacos , Neoplasias Pulmonares/tratamiento farmacológico , Células Madre Neoplásicas/efectos de los fármacos , Piridazinas/farmacología , Estearoil-CoA Desaturasa/antagonistas & inhibidores , Tiadiazoles/farmacología , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/enzimología , Adenocarcinoma/patología , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Biomarcadores de Tumor/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/enzimología , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas/enzimología , Carcinoma de Células Escamosas/patología , Estudios de Casos y Controles , Proliferación Celular/efectos de los fármacos , Quimioterapia Combinada , Estrés del Retículo Endoplásmico/efectos de los fármacos , Humanos , Neoplasias Pulmonares/enzimología , Neoplasias Pulmonares/patología , Estadificación de Neoplasias , Células Madre Neoplásicas/enzimología , Células Madre Neoplásicas/patología , Pronóstico , Tasa de Supervivencia , Células Tumorales Cultivadas
18.
FEBS Lett ; 580(26): 6109-14, 2006 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-17056040

RESUMEN

Apoptosis represents a fundamental process during fetal/post-natal testis development. Therefore pro- and anti-apoptotic proteins are essential to regulate testis physiology. c-Flip(L) is a known inhibitor of caspase 8/10 activity; in this study its perinatal expression in mouse male germ cells was investigated. In testis sections and seminiferous tubule whole mount c-Flip(L) was found to be expressed in undifferentiated spermatogonia and to co-localize with germ stem cells markers. In vivo investigations in the vitamin-A deficient mouse, lacking differentiated germ cells, confirmed c-Flip(L) expression in undifferentiated spermatogonia. Further analyses showed Fas expression but no significant caspase 8/10 activity when c-Flip(L) was highly expressed. Altogether these data suggest that c-Flip may control the survival rate of undifferentiated spermatogonia.


Asunto(s)
Proteína Reguladora de Apoptosis Similar a CASP8 y FADD/análisis , Proteína Reguladora de Apoptosis Similar a CASP8 y FADD/fisiología , Células Germinativas/química , Espermatogonias/química , Animales , Caspasas , Diferenciación Celular , Supervivencia Celular , Técnicas Inmunológicas , Masculino , Ratones , Ratones Endogámicos , Túbulos Seminíferos/citología , Testículo/citología , Receptor fas
19.
FASEB J ; 19(14): 2048-50, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16174786

RESUMEN

Induction of human sperm chemotaxis is an established phenomenon, though signaling systems physiologically involved have not been identified. Recently, it has been demonstrated that RANTES is present in the follicular fluid and that this molecule is a chemoactractant for human spermatozoa. However, the presence of beta-chemokine receptors on human spermatozoa has never been reported. By cytometric, Western blotting and immunofluorescence analysis, we demonstrate the presence of CCR5 and CCR3 on ejaculated spermatozoa from healthy subjects. CCR5 was detected in the periacrosomal region of the sperm surface, whereas CCR3 was also present in the postacrosomal cap. Individual variability was observed on CCR5 and CCR3 positive sperm percentages. Presence of Delta32+/-) mutation was demonstrated in two subjects expressing CCR5 in half of the ejaculated spermatozoa. Our findings represent the missing information in favor of the possibility that beta-chemokines and their receptors are involved in sperm chemotaxis. Identification of molecular mechanisms of sperm chemotaxis may allow us to identify predictive parameters of sperm fertilizing ability in hypofertile or infertile subjects. Finally, both CCR5 and CCR3 expressed on the sperm cell surface may be involved in HIV-1 adhesion to spermatozoa, thus allowing these cells to perform as virion cellular carriers during sexual transmission of HIV-1 infection.


Asunto(s)
Receptores CCR5/biosíntesis , Receptores de Quimiocina/biosíntesis , Motilidad Espermática , Espermatozoides/metabolismo , Western Blotting , Quimiotaxis , Eyaculación , Regulación de la Expresión Génica , Genotipo , VIH-1/metabolismo , Haplotipos , Humanos , Masculino , Microscopía Fluorescente , Mutación , Receptores CCR3 , Receptores CCR5/fisiología , Receptores de Quimiocina/fisiología , Espermatozoides/virología
20.
ISA Trans ; 60: 228-243, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26639055

RESUMEN

This paper analyzes the fragility issue of fractional-order proportional-integral-derivative controllers applied to integer first-order plus-dead-time processes. In particular, the effects of the variations of the controller parameters on the achieved control system robustness and performance are investigated. Results show that this kind of controllers is more fragile with respect to the standard proportional-integral-derivative controllers and therefore a significant attention should be paid by the user in their tuning.

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