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1.
J Cell Mol Med ; 19(2): 327-39, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25444175

RESUMO

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.


Assuntos
Androgênios/farmacologia , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Fator Regulador 3 de Interferon/metabolismo , Próstata/efeitos dos fármacos , Próstata/metabolismo , Animais , Apoptose/fisiologia , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos NOD
2.
Biol Reprod ; 90(3): 53, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24478388

RESUMO

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.


Assuntos
Proteínas de Ligação ao Cálcio/fisiologia , Peptídeos e Proteínas de Sinalização Intercelular/fisiologia , Proteínas de Membrana/fisiologia , Receptores Notch/fisiologia , Células de Sertoli/fisiologia , Linfócitos T Reguladores/fisiologia , Animais , Western Blotting , Antígenos CD4/biossíntese , Antígenos CD4/genética , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ciclo Celular/genética , Imunoprecipitação da Cromatina , Citometria de Fluxo , Fatores de Transcrição Forkhead/fisiologia , Peptídeos e Proteínas de Sinalização Intercelular/genética , Proteína Jagged-1 , Masculino , Proteínas de Membrana/genética , Camundongos , Cultura Primária de Células , Reação em Cadeia da Polimerase em Tempo Real , Receptores Notch/genética , Proteínas Serrate-Jagged , Supressão Genética , Transfecção , Fator de Crescimento Transformador beta/fisiologia
3.
Apoptosis ; 17(11): 1210-22, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22923157

RESUMO

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.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Células Epiteliais/patologia , Neoplasias da Próstata/patologia , Fator de Necrose Tumoral alfa/farmacologia , Adenina/análogos & derivados , Western Blotting , Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD/genética , Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD/metabolismo , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Ativação Enzimática/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Proteína Forkhead Box O3 , Fatores de Transcrição Forkhead/metabolismo , Humanos , Masculino , Proteínas Associadas aos Microtúbulos/metabolismo , Regiões Promotoras Genéticas/genética , Neoplasias da Próstata/enzimologia , Complexo de Endopeptidases do Proteassoma/metabolismo , Inibidores de Proteassoma/farmacologia , Proteólise/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Sirolimo/farmacologia , Transcrição Gênica/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
4.
Hum Reprod ; 27(8): 2267-76, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22647452

RESUMO

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.


Assuntos
Clusterina/química , Dano ao DNA , Hipertensão/metabolismo , Espermatozoides/metabolismo , Adulto , Estudos de Casos e Controles , Estudos de Coortes , Fragmentação do DNA , Citometria de Fluxo/métodos , Glicoproteínas/química , Humanos , Hipertensão/patologia , Marcação In Situ das Extremidades Cortadas , Masculino , Microscopia de Fluorescência/métodos , Pessoa de Meia-Idade , Análise de Regressão , Sêmen/metabolismo , Espermatozoides/patologia
5.
Comput Methods Programs Biomed ; 219: 106763, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35349908

RESUMO

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.


Assuntos
Hipnose , Propofol , Anestesia Geral , Anestésicos Intravenosos , Humanos , Remifentanil
6.
Cancer Biol Med ; 2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-34018387

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-20615237

RESUMO

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.


Assuntos
Adenocarcinoma/complicações , Caquexia/etiologia , Neoplasias do Colo/complicações , Neoplasias Pulmonares/complicações , Músculo Esquelético/patologia , Atrofia Muscular/etiologia , Adenocarcinoma/patologia , Animais , Apoptose , Western Blotting , Caquexia/patologia , Proliferação de Células , Neoplasias do Colo/patologia , Modelos Animais de Doenças , Citometria de Fluxo , Técnicas Imunoenzimáticas , Neoplasias Pulmonares/secundário , Camundongos , Camundongos Endogâmicos BALB C , Atrofia Muscular/patologia , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
8.
Anticancer Res ; 40(10): 5379-5391, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32988857

RESUMO

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.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Poli I-C/farmacologia , Receptor 3 Toll-Like/genética , Apoptose/efeitos dos fármacos , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Proliferação de Células/efeitos dos fármacos , Feminino , Citometria de Fluxo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Células MCF-7 , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-myc/genética , Transdução de Sinais/efeitos dos fármacos , Receptor 3 Toll-Like/agonistas
9.
Front Immunol ; 11: 350, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32231663

RESUMO

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.


Assuntos
Aterosclerose/imunologia , Autofagia/fisiologia , Linfócitos T Reguladores/citologia , Aldosterona/farmacologia , Animais , Apolipoproteínas E/fisiologia , Aterosclerose/fisiopatologia , Aterosclerose/terapia , Autofagia/efeitos dos fármacos , Diferenciação Celular , Polaridade Celular , Modelos Animais de Doenças , Fatores de Transcrição Forkhead/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Placa Aterosclerótica/imunologia , Linfócitos T Reguladores/fisiologia , Fator de Crescimento Transformador beta/farmacologia
10.
Carcinogenesis ; 29(7): 1334-42, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18566014

RESUMO

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.


Assuntos
Apoptose/fisiologia , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Proteína Quinase C-alfa/metabolismo , Receptor 3 Toll-Like/metabolismo , Apoptose/efeitos dos fármacos , Processos de Crescimento Celular/efeitos dos fármacos , Processos de Crescimento Celular/fisiologia , Linhagem Celular Tumoral , Ativação Enzimática , Humanos , Interferon beta/metabolismo , MAP Quinase Quinase 4/metabolismo , Masculino , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fosforilação , Poli I-C/farmacologia , Neoplasias da Próstata/enzimologia , Neoplasias da Próstata/genética , Receptores Androgênicos/biossíntese , Receptores Androgênicos/genética , Receptor 3 Toll-Like/antagonistas & inibidores , Transfecção , Proteína Supressora de Tumor p53/biossíntese , Proteína Supressora de Tumor p53/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
11.
Neurol Res ; 30(2): 160-9, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18397608

RESUMO

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.


Assuntos
Caquexia/patologia , Células-Tronco Hematopoéticas/fisiologia , Músculo Esquelético/patologia , Animais , Antígenos Ly/metabolismo , Peso Corporal , Caquexia/complicações , Caquexia/etiologia , DNA/metabolismo , Modelos Animais de Doenças , Feminino , Citometria de Fluxo/métodos , Regulação Neoplásica da Expressão Gênica/fisiologia , Antígenos Comuns de Leucócito/metabolismo , Linfócitos/patologia , Macrófagos/patologia , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Atrofia Muscular/etiologia , NADP Trans-Hidrogenases/metabolismo , Neoplasias/complicações , Peroxidase/metabolismo , Fatores de Tempo
12.
Oncotarget ; 9(56): 30905-30918, 2018 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-30112117

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-15735039

RESUMO

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.


Assuntos
Citocinas/farmacologia , Inibidores Enzimáticos/farmacologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Inibidores de Histona Desacetilases , Ácido Valproico/farmacologia , Antígeno AC133 , Acetilação/efeitos dos fármacos , Antígenos CD , Antígenos CD34/biossíntese , Apoptose/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Processos de Crescimento Celular/efeitos dos fármacos , Cromatina/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Glicoproteínas/metabolismo , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/enzimologia , Células-Tronco Hematopoéticas/imunologia , Proteínas de Homeodomínio/metabolismo , Humanos , Peptídeos/metabolismo , Trombopoetina/farmacologia , Fatores de Transcrição/metabolismo
14.
ISA Trans ; 66: 344-361, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27988040

RESUMO

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 ; 147: 63-83, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28734531

RESUMO

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.


Assuntos
Anestesia/métodos , Hipnose , Propofol/administração & dosagem , Algoritmos , Anestésicos Intravenosos , Humanos , Método de Monte Carlo
16.
Comput Methods Programs Biomed ; 144: 21-35, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28495004

RESUMO

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.


Assuntos
Anestesia/métodos , Hipnose Anestésica , Hipnóticos e Sedativos/administração & dosagem , Propofol/administração & dosagem , Algoritmos , Humanos , Modelos Teóricos
17.
Cancer Lett ; 406: 93-104, 2017 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-28797843

RESUMO

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.


Assuntos
Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Neoplasias Pulmonares/tratamento farmacológico , Células-Tronco Neoplásicas/efeitos dos fármacos , Piridazinas/farmacologia , Estearoil-CoA Dessaturase/antagonistas & inibidores , Tiadiazóis/farmacologia , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/enzimologia , Adenocarcinoma/patologia , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Biomarcadores Tumorais/metabolismo , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/enzimologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/enzimologia , Carcinoma de Células Escamosas/patologia , Estudos de Casos e Controles , Proliferação de Células/efeitos dos fármacos , Quimioterapia Combinada , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Humanos , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/patologia , Estadiamento de Neoplasias , Células-Tronco Neoplásicas/enzimologia , Células-Tronco Neoplásicas/patologia , Prognóstico , Taxa de Sobrevida , Células Tumorais Cultivadas
18.
FEBS Lett ; 580(26): 6109-14, 2006 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-17056040

RESUMO

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.


Assuntos
Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD/análise , Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD/fisiologia , Células Germinativas/química , Espermatogônias/química , Animais , Caspases , Diferenciação Celular , Sobrevivência Celular , Técnicas Imunológicas , Masculino , Camundongos , Camundongos Endogâmicos , Túbulos Seminíferos/citologia , Testículo/citologia , Receptor fas
19.
FASEB J ; 19(14): 2048-50, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16174786

RESUMO

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.


Assuntos
Receptores CCR5/biossíntese , Receptores de Quimiocinas/biossíntese , Motilidade dos Espermatozoides , Espermatozoides/metabolismo , Western Blotting , Quimiotaxia , Ejaculação , Regulação da Expressão Gênica , Genótipo , HIV-1/metabolismo , Haplótipos , Humanos , Masculino , Microscopia de Fluorescência , Mutação , Receptores CCR3 , Receptores CCR5/fisiologia , Receptores de Quimiocinas/fisiologia , Espermatozoides/virologia
20.
ISA Trans ; 60: 228-243, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26639055

RESUMO

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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