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2.
Eur Rev Med Pharmacol Sci ; 25(3): 1548-1556, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33629324

RESUMEN

OBJECTIVE: The study was aimed to investigate the role of radiotherapy (RT) as a risk factor for reactivation or worsening of symptoms in patients affected by rheumatoid arthritis (RA) PATIENTS AND METHODS: This is a single-center retrospective observational study on RA patients who developed cancer requiring RT during the course of the disease. The control group consisted of RA patients with cancer who did not undergo RT. In both groups, the disease activity was evaluated at baseline and at 6 and 12 months through the DAS28 index. A relapse was defined as an increase of >20% in DAS28. A radiotherapist evaluated total and daily doses and timing of radiation. Acute and late toxicity was defined as events occurring within 90 days from the start and more than 90 days after the completion of RT, respectively. RESULTS: Seventy-two RA patients (38F/34M; mean age: 70±9 years; mean disease duration: 13±9 years), 29 (40.2%) of whom received radiotherapy (mean age 72.9±9 years), were enrolled. The most frequent malignancies were breast (27.2%), thyroid (9.8%), and skin (7%). Between radio-treated and non-radio-treated patients, no significant differences in RA reactivation (6/29 vs. 17/43; p=0.12) or mean exacerbation time (6.7 ± 4.9 months compared to 6.4 ± 4.1 months; p=0.78) were found. Overall, RT was well tolerated with low rates of both acute and late toxicity. CONCLUSIONS: In RA patients, RT was well tolerated and not associated with an increased risk of articular flares. Properly designed prospective clinical studies with a larger number of patients should be performed to confirm these data.


Asunto(s)
Antirreumáticos/uso terapéutico , Artritis Reumatoide/tratamiento farmacológico , Neoplasias/radioterapia , Anciano , Femenino , Humanos , Masculino , Estudios Retrospectivos
4.
Ann Oncol ; 30(6): 921-926, 2019 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-30778520

RESUMEN

BACKGROUND: In human epidermal growth factor receptor 2 (HER2+) breast cancers, neoadjuvant trials of chemotherapy plus anti-HER2 treatment consistently showed lower pathologic complete response (pCR) rates in hormone receptor (HR) positive versus negative tumors. The PerELISA study was aimed to evaluate the efficacy of a de-escalated, chemotherapy-free neoadjuvant regimen in HR+/HER2+ breast cancer patients selected on the basis of Ki67 inhibition after 2-week letrozole. PATIENTS AND METHODS: PerELISA is a phase II, multicentric study for postmenopausal patients with HR+/HER2+ operable breast cancer. Patients received 2-week letrozole, and then underwent re-biopsy for Ki67 evaluation. Patients classified as molecular responders (Ki67 relative reduction >20% from baseline) continued letrozole and started trastuzumab-pertuzumab for five cycles. Patients classified as molecular non-responders started weekly paclitaxel for 13 weeks combined with trastuzumab-pertuzumab. Primary aim was breast and axillary pCR. According to a two-stage Simon's design, to reject the null hypothesis, at least 8/43 pCR had to be documented. RESULTS: Sixty-four patients were enrolled, 44 were classified as molecular responders. All these patients completed the assigned treatment with letrozole-trastuzumab-pertuzumab and underwent surgery. A pCR was observed in 9/44 cases (20.5%, 95% confidence interval 11.1% to 34.5%). Among molecular non-responders, 16/17 completed treatment and underwent surgery, with pCR observed in 81.3% of the cases. PAM50 intrinsic subtype was significantly associated with Ki67 response and pCR. Among molecular responders, the pCR rate was significantly higher in HER2-enriched than in other subtypes (45.5% versus 13.8%, P = 0.042). CONCLUSIONS: The primary end point of the study was met, by reaching the pre-specified pCRs. In patients selected using Ki67 reduction after short-term letrozole exposure, a meaningful pCR rate can be achieved without chemotherapy. PAM50 intrinsic subtyping further refines our ability to identify a subset of patients for whom chemotherapy might be spared. EUDRACT NUMBER: 2013-002662-40. CLINICALTRIALS.GOV IDENTIFIER: NCT02411344.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Antígeno Ki-67/metabolismo , Receptor ErbB-2/metabolismo , Receptores de Estrógenos/metabolismo , Receptores de Progesterona/metabolismo , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales Humanizados/administración & dosificación , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Neoplasias de la Mama/cirugía , Carcinoma Ductal de Mama/tratamiento farmacológico , Carcinoma Ductal de Mama/metabolismo , Carcinoma Ductal de Mama/patología , Carcinoma Ductal de Mama/cirugía , Carcinoma Lobular/tratamiento farmacológico , Carcinoma Lobular/metabolismo , Carcinoma Lobular/patología , Carcinoma Lobular/cirugía , Relación Dosis-Respuesta a Droga , Femenino , Estudios de Seguimiento , Humanos , Letrozol/administración & dosificación , Persona de Mediana Edad , Terapia Neoadyuvante , Invasividad Neoplásica , Pronóstico , Inducción de Remisión , Trastuzumab/administración & dosificación
5.
G Chir ; 39(6): 383-387, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30563603

RESUMEN

AIM: Complication of Crohn's disease (CD) of the small intestine is small bowel adenocarcinoma (SBA). A lot of studies on Crohn's disease have estimated the increased relative risk of small bowel carcinoma compared to the general population. In clinical settings, it is difficult to detect SBA in CD, therefore most of cases are diagnosed after surgery for strictures without suspicion of malignancy. CASE REPORT: The present case concerns a 48-year-old man with a suspicious 5-year history of untreated chronic inflammatory bowel disease. The patient was admitted to our unit with persistent abdominal pain, 20 kg weight loss and intestinal obstruction, confirmed at CT scans. It was performed an emergency laparotomy, terminal ileus was resected and intestinal continuity was restored. Histological examination revealed a poorly differentiated adenocarcinoma. DISCUSSION: The risk factors of SBA include long-standing and extensive Crohn's disease, young age, male sex, smoke, early onset, complications such as strictures and fistulas The most common clinical presentation of small bowel carcinoma in Crohn's disease is intestinal obstruction accompanied by wheight loss. The diagnosis is very difficult because imaging techniques may not be able to differentiate areas of small bowel carcinomas from benign fibrotic or acute inflammatory strictures. CONCLUSION: Small bowel adenocarcinoma is a rare disease but this evenience must be considered in patients with strictures for Crohn's disease. Preoperative diagnosis is still highly challenging despite significant radiological and endoscopic progress.


Asunto(s)
Adenocarcinoma/etiología , Enfermedad de Crohn/complicaciones , Neoplasias del Íleon/etiología , Adenocarcinoma/secundario , Adenocarcinoma/cirugía , Antirreumáticos/efectos adversos , Antirreumáticos/uso terapéutico , Enfermedad de Crohn/tratamiento farmacológico , Humanos , Neoplasias del Íleon/cirugía , Huésped Inmunocomprometido , Inmunosupresores/uso terapéutico , Infliximab/efectos adversos , Infliximab/uso terapéutico , Metástasis Linfática , Masculino , Desnutrición/etiología , Desnutrición/terapia , Persona de Mediana Edad , Nutrición Parenteral Total , Fumar/efectos adversos , Tiempo de Tratamiento , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores
6.
Dalton Trans ; 47(10): 3329-3338, 2018 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-29423483

RESUMEN

The formation of halide and hydroxide anion complexes with two ligands L1 (3,6-bis(morpholin-4-ylmethyl)-1,2,4,5-tetrazine) and L2 (3,6-bis(morpholin-4-ylethyl)-1,2,4,5-tetrazine) was studied in aqueous solution, by means of potentiometric and ITC procedures. In the solid state, HF2-, Cl- and Br- complexes of H2L22+ were analysed by single crystal XRD measurements. Further information on the latter was obtained with the use of density functional theory (DFT) calculations in combination with the polarizable continuum model (PCM). The presence of two halide or bifluoride HF2- (F-H-F-) anions forming anion-π interactions, respectively above and below the ligand tetrazine ring, is the leitmotiv of the [(H2L2)X2] (X = HF2, Cl, Br, I) complexes in the solid state, while hydrogen bonding between the anions and protonated morpholine ligand groups contributes to strengthen the anion-ligand interaction, in particular in the case of Cl- and Br-. In contrast to the solid state, only the anion : ligand complexes of 1 : 1 stoichiometry were found in solution. The stability of these complexes displays the peculiar trend I- > F- > Br- > Cl- which was rationalized in terms of electrostatic, hydrogen bond, anion-π interactions and solvent effects. DFT calculations performed on [(H2L2)X]+ (X = F, Cl, Br, I) in PCM water suggested that the ligand assumes a U-shaped conformation to form one anion-π and two salt bridge interactions with the included anions and furnished structural information to interpret the solvation effects affecting complex formation. The formation of hydroxide anion complexes with neutral (not protonated) L1 and L2 molecules represents an unprecedented case in water. The stability of the [L(OH)]- (L = L1, L2) complexes is comparable to or higher than the stability of halide complexes with protonated ligand molecules, their formation being promoted by largely favourable enthalpic contributions that prevail over unfavourable entropic changes.

7.
Methods Enzymol ; 588: 171-186, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28237100

RESUMEN

It is widely acknowledged that mitochondria are highly active structures that rapidly respond to cellular and environmental perturbations by changing their shape, number, and distribution. Mitochondrial remodeling is a key component of diverse biological processes, ranging from cell cycle progression to autophagy. In this chapter, we describe different methodologies for the morphological study of the mitochondrial network. Instructions are given for the preparation of samples for fluorescent microscopy, based on genetically encoded strategies or the employment of synthetic fluorescent dyes. We also propose detailed protocols to analyze mitochondrial morphometric parameters from both three-dimensional and bidimensional datasets. Finally, we describe a protocol for the visualization and quantification of mitochondrial structures through electron microscopy.


Asunto(s)
Autofagia , Microscopía Confocal/métodos , Microscopía Electrónica/métodos , Mitocondrias/ultraestructura , Mitofagia , Imagen Óptica/métodos , Animales , Colorantes Fluorescentes/análisis , Proteínas Fluorescentes Verdes/análisis , Humanos , Mitocondrias/metabolismo
8.
Int Rev Cell Mol Biol ; 328: 49-103, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28069137

RESUMEN

Mitochondria, the organelles that function as the powerhouse of the cell, have been increasingly linked to the pathogenesis of many neurological disorders, including multiple sclerosis (MS). MS is a chronic inflammatory demyelinating disease of the central nervous system (CNS) and a leading cause of neurological disability in young adults in the western world. Its etiology remains unknown, and while the inflammatory component of MS has been heavily investigated and targeted for therapeutic intervention, the failure of remyelination and the process of axonal degeneration are still poorly understood. Recent studies suggest a role of mitochondrial dysfunction in the neurodegenerative aspects of MS. This review is focused on mitochondrial functions under physiological conditions and the consequences of mitochondrial alterations in various CNS disorders. Moreover, we summarize recent findings linking mitochondrial dysfunction to MS and discuss novel therapeutic strategies targeting mitochondria-related pathways as well as emerging experimental approaches for modeling mitochondrial disease.


Asunto(s)
Mitocondrias/metabolismo , Esclerosis Múltiple/genética , Animales , Modelos Animales de Enfermedad , Humanos , Modelos Biológicos , Terapia Molecular Dirigida , Esclerosis Múltiple/patología , Esclerosis Múltiple/terapia , Degeneración Nerviosa/patología
9.
Cell Death Dis ; 6: e1786, 2015 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-26068794

RESUMEN

High-mobility group box 1 (HMGB1) is an inflammatory molecule that has a critical role in the initiation and progression of malignant mesothelioma (MM). Aspirin (acetylsalicylic acid, ASA) is the most widely used nonsteroidal anti-inflammatory drug that reduces the incidence, metastatic potential and mortality of many inflammation-induced cancers. We hypothesized that ASA may exert anticancer properties in MM by abrogating the carcinogenic effects of HMGB1. Using HMGB1-secreting and -non-secreting human MM cell lines, we determined whether aspirin inhibited the hallmarks of HMGB1-induced MM cell growth in vitro and in vivo. Our data demonstrated that ASA and its metabolite, salicylic acid (SA), inhibit motility, migration, invasion and anchorage-independent colony formation of MM cells via a novel HMGB1-mediated mechanism. ASA/SA, at serum concentrations comparable to those achieved in humans taking therapeutic doses of aspirin, and BoxA, a specific inhibitor of HMGB1, markedly reduced MM growth in xenograft mice and significantly improved survival of treated animals. The effects of ASA and BoxA were cyclooxygenase-2 independent and were not additive, consistent with both acting via inhibition of HMGB1 activity. Our findings provide a rationale for the well documented, yet poorly understood antitumorigenic activity of aspirin, which we show proceeds via HMGB1 inhibition. Moreover, the use of BoxA appears to allow a more efficient HMGB1 targeting while eluding the known gastrointestinal side effects of ASA. Our findings are directly relevant to MM. Given the emerging importance of HMGB1 and its tumor-promoting functions in many cancer types, and of aspirin in cancer prevention and therapy, our investigation is poised to provide broadly applicable information.


Asunto(s)
Antiinflamatorios no Esteroideos/uso terapéutico , Aspirina/uso terapéutico , Proteína HMGB1/antagonistas & inhibidores , Neoplasias Pulmonares/tratamiento farmacológico , Mesotelioma/tratamiento farmacológico , Ácido Salicílico/uso terapéutico , Células 3T3 , Animales , Antineoplásicos/uso terapéutico , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Ciclooxigenasa 2/genética , Ciclooxigenasa 2/metabolismo , Transición Epitelial-Mesenquimal/efectos de los fármacos , Femenino , Proteína HMGB1/metabolismo , Neoplasias Pulmonares/metabolismo , Mesotelioma/metabolismo , Mesotelioma Maligno , Ratones , Ratones Noqueados , Ratones SCID , Invasividad Neoplásica/patología , Ensayos Antitumor por Modelo de Xenoinjerto
10.
Cell Death Differ ; 21(8): 1198-208, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24658399

RESUMEN

Mitochondrial defects, affecting parameters such as mitochondrial number and shape, levels of respiratory chain complex components and markers of oxidative stress, have been associated with the appearance and progression of multiple sclerosis. Nevertheless, mitochondrial physiology has never been monitored during oligodendrocyte progenitor cell (OPC) differentiation, especially in OPCs challenged with proinflammatory cytokines. Here, we show that tumor necrosis factor alpha (TNF-α) inhibits OPC differentiation, accompanied by altered mitochondrial calcium uptake, mitochondrial membrane potential, and respiratory complex I activity as well as increased reactive oxygen species production. Treatment with a mitochondrial uncoupler (FCCP) to mimic mitochondrial impairment also causes cells to accumulate at the progenitor stage. Interestingly, AMP-activated protein kinase (AMPK) levels increase during TNF-α exposure and inhibit OPC differentiation. Overall, our data indicate that TNF-α induces metabolic changes, driven by mitochondrial impairment and AMPK activation, leading to the inhibition of OPC differentiation.


Asunto(s)
Mitocondrias/metabolismo , Oligodendroglía/citología , Oligodendroglía/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Animales , Diferenciación Celular/fisiología , Esclerosis Múltiple/metabolismo , Esclerosis Múltiple/patología , Ratas , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal
11.
Cell Death Differ ; 20(12): 1631-43, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23811847

RESUMEN

The tumor suppressor activity of PTEN (phosphatase and tensin homolog deleted on chromosome 10) is thought to be largely attributable to its lipid phosphatase activity. PTEN dephosphorylates the lipid second messenger phosphatidylinositol 3,4,5-trisphosphate to directly antagonize the phosphoinositide 3-kinase-Akt pathway and prevent the activating phosphorylation of Akt. PTEN has also other proposed mechanisms of action, including a poorly characterized protein phosphatase activity, protein-protein interactions, as well as emerging functions in different compartment of the cells such as nucleus and mitochondria. We show here that a fraction of PTEN protein localizes to the endoplasmic reticulum (ER) and mitochondria-associated membranes (MAMs), signaling domains involved in calcium ((2+)) transfer from the ER to mitochondria and apoptosis induction. We demonstrate that PTEN silencing impairs ER Ca(2+) release, lowers cytosolic and mitochondrial Ca(2+) transients and decreases cellular sensitivity to Ca(2+)-mediated apoptotic stimulation. Specific targeting of PTEN to the ER is sufficient to enhance ER-to-mitochondria Ca(2+) transfer and sensitivity to apoptosis. PTEN localization at the ER is further increased during Ca(2+)-dependent apoptosis induction. Importantly, PTEN interacts with the inositol 1,4,5-trisphosphate receptors (IP3Rs) and this correlates with the reduction in their phosphorylation and increased Ca(2+) release. We propose that ER-localized PTEN regulates Ca(2+) release from the ER in a protein phosphatase-dependent manner that counteracts Akt-mediated reduction in Ca(2+) release via IP3Rs. These findings provide new insights into the mechanisms and the extent of PTEN tumor-suppressive functions, highlighting new potential strategies for therapeutic intervention.


Asunto(s)
Apoptosis , Señalización del Calcio , Retículo Endoplásmico/enzimología , Membranas Mitocondriales/enzimología , Fosfohidrolasa PTEN/metabolismo , Animales , Calcio/metabolismo , Silenciador del Gen , Células HEK293 , Homeostasis , Humanos , Ratones , Fracciones Subcelulares/enzimología
12.
Cell Death Differ ; 20(2): 198-208, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22935610

RESUMEN

In response to intense stress, the tumor protein p53 (p53) tumor suppressor rapidly mounts a direct mitochondrial death program that precedes transcription-mediated apoptosis. By eliminating severely damaged cells, this pathway contributes to tumor suppression as well as to cancer cell killing induced by both genotoxic drugs and non-genotoxic p53-reactivating molecules. Here we have explored the role had in this pathway by the prolyl-isomerase Pin1 (peptidylprolyl cis/trans isomerase, NIMA-interacting 1), a crucial transducer of p53's phosphorylation into conformational changes unleashing its pro-apoptotic activity. We show that Pin1 promotes stress-induced localization of p53 to mitochondria both in vitro and in vivo. In particular, we demonstrate that upon stress-induced phosphorylation of p53 on Ser46 by homeodomain interacting protein kinase 2, Pin1 stimulates its mitochondrial trafficking signal, that is, monoubiquitination. This pathway is induced also by the p53-activating molecule RITA, and we demonstrate the strong requirement of Pin1 for the induction of mitochondrial apoptosis by this compound. These findings have significant implications for treatment of p53-expressing tumors and for prospective use of p53-activating compounds in clinics.


Asunto(s)
Mitocondrias/metabolismo , Isomerasa de Peptidilprolil/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Animales , Apoptosis/efectos de los fármacos , Proteínas Portadoras/antagonistas & inhibidores , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Línea Celular Tumoral , Furanos/farmacología , Células HCT116 , Humanos , Ratones , Isomerasa de Peptidilprolil/antagonistas & inhibidores , Isomerasa de Peptidilprolil/genética , Fosforilación , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Interferencia de ARN , ARN Interferente Pequeño/metabolismo , Transcripción Genética , Proteína p53 Supresora de Tumor/deficiencia , Proteína p53 Supresora de Tumor/genética
13.
Anim Reprod Sci ; 132(1-2): 101-10, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22541277

RESUMEN

The cDNA sequences of vitellogenin receptor proteins (VgR(+) and VgR(-)), containing or lacking the O-linked sugar domain, were determined in Atlantic bluefin tuna (Thunnus thynnus L.). VgR(-) gene expression in the ovary was compared in captive-reared and wild Atlantic bluefin tuna during the reproductive cycle. Gonad samples from adult fish were sampled from 2008 to 2010 from stocks reared in captivity at different commercial fattening operations in the Mediterranean Sea and from wild individuals caught either by traditional tuna traps during their migration towards the spawning grounds in the Mediterranean Sea or by the long-line artisanal fishery. In addition, juvenile male and female Atlantic bluefin tuna were sampled from a farming facility, to obtain baseline information and pre-adulthood amounts of VgR(-). The total length of VgR(+) cDNA was 4006 nucleotides (nt) and that of VgR(-) was 3946 nt. Relative amounts of VgR(-) were greater in juvenile females and in those adults having only previtellogenic oocytes (119 ± 55 and 146 ± 26 folds more than juvenile males, respectively). Amounts of VgR(-) were less in individuals with yolked oocytes (ripening stage, May-June) and increased after spawning in July (92 ± 20 and 113 ± 13 folds more than juvenile males in ripening and post-spawning fish, respectively). These data suggest that regulation of VgR(-) is not under oestrogen control. During the ripening period, greater VgR(-) gene expression was observed in wild fish than in fish reared in captivity, possibly because of (a) differences in water temperature exposure and/or energy storage, and/or (b) an inadequate diet in reared Atlantic bluefin tuna.


Asunto(s)
Proteínas del Huevo/biosíntesis , Ovario/fisiología , Receptores de Superficie Celular/biosíntesis , Atún/metabolismo , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Proteínas del Huevo/genética , Femenino , Regulación de la Expresión Génica , Histocitoquímica/veterinaria , Masculino , Mar Mediterráneo , Datos de Secuencia Molecular , Oocitos/fisiología , Ovario/metabolismo , ARN/química , ARN/genética , Receptores de Superficie Celular/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/veterinaria , Estaciones del Año , Alineación de Secuencia , Análisis de Secuencia de ADN , Atún/genética
14.
Cell Death Dis ; 3: e304, 2012 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-22552281

RESUMEN

Ca²âº transfer from endoplasmic reticulum (ER) to mitochondria can trigger apoptotic pathways by inducing release of mitochondrial pro-apoptotic factors. Three different types of inositol 1,4,5-trisphosphate receptor (IP3R) serve to discharge Ca²âº from ER, but possess some peculiarities, especially in apoptosis induction. The anti-apoptotic protein Akt can phosphorylate all IP3R isoforms and protect cells from apoptosis, reducing ER Ca²âº release. However, it has not been elucidated which IP3R subtypes mediate these effects. Here, we show that Akt activation in COS7 cells, which lack of IP3R I, strongly suppresses IP3-mediated Ca²âº release and apoptosis. Conversely, in SH-SY 5Y cells, which are type III-deficient, Akt is unable to modulate ER Ca²âº flux, losing its anti-apoptotic activity. In SH-SY 5Y-expressing subtype III, Akt recovers its protective function on cell death, by reduction of Ca²âº release. Moreover, regulating Ca²âº flux to mitochondria, Akt maintains the mitochondrial integrity and delays the trigger of apoptosis, in a type III-dependent mechanism. These results demonstrate a specific activity of Akt on IP3R III, leading to diminished Ca²âº transfer to mitochondria and protection from apoptosis, suggesting an additional level of cell death regulation mediated by Akt.


Asunto(s)
Apoptosis , Calcio/metabolismo , Retículo Endoplásmico/metabolismo , Receptores de Inositol 1,4,5-Trifosfato/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Animales , Células COS , Línea Celular Tumoral , Chlorocebus aethiops , Células HeLa , Humanos , Receptores de Inositol 1,4,5-Trifosfato/genética , Mitocondrias/metabolismo , Fosforilación , Transfección
15.
Cell Death Differ ; 19(8): 1390-7, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22402588

RESUMEN

The transcription factor signal transducer and activator of transcription 3 (STAT3) acts downstream of many pro-oncogenic signals, including cytokines, growth factors and oncogenes, and is accordingly constitutively active in a wide variety of tumors that often become addicted to it. Moreover, STAT3 is a key player in mediating inflammation-driven tumorigenesis, where its aberrant continuous activation is typically triggered by local or systemic production of the pro-inflammatory cytokine IL-6. We recently showed that mouse embryonic fibroblasts (MEFs) derived from STAT3C k/in mice, which express physiological levels of the constitutively active mutant STAT3C, display features of transformed cells such as increased proliferation, resistance to apoptosis and senescence, and aerobic glycolysis. Here, we show that pre-existing constitutively active STAT3 is sufficient to prime primary MEFs for malignant transformation upon spontaneous immortalization. Transformation is strictly STAT3-dependent and correlates with high resistance to apoptosis and enhanced expression of anti-apoptotic/pro-survival genes. Additionally, hypoxia inducible factor (HIF)-1α level is elevated by twofold and contributes to STAT3 oncogenic activity by supporting high rates of aerobic glycolysis. Thus, constitutively active STAT3, an accepted essential factor for tumor growth/progression, can also act as a first hit in multistep carcinogenesis; this ability to predispose cells to malignant transformation may be particularly relevant in the pro-oncogenic niche represented by chronically inflamed tissues.


Asunto(s)
Transformación Celular Neoplásica/patología , Fibroblastos/citología , Factor de Transcripción STAT3/metabolismo , Células 3T3 , Animales , Apoptosis/fisiología , Línea Celular Tumoral , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/metabolismo , Progresión de la Enfermedad , Femenino , Fibroblastos/metabolismo , Ratones , Ratones Transgénicos , Factor de Transcripción STAT3/genética , Transducción de Señal
16.
Cell Death Differ ; 18(9): 1450-6, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21475307

RESUMEN

The development of malignant tumors results from deregulated proliferation or an inability of cells to undergo apoptotic cell death. Experimental works of the past decade have highlighted the importance of calcium (Ca(2+)) in the regulation of apoptosis. Several studies indicate that the Ca(2+) content of the endoplasmic reticulum (ER) determines the cell's sensitivity to apoptotic stress and perturbation of ER Ca(2+) homeostasis appears to be a key component in the development of several pathological situations. Sensitivity to apoptosis depends on the ability of cells to transfer Ca(2+) from the ER to the mitochondria. The physical platform for the interplay between the ER and mitochondria is a domain of the ER called the mitochondria-associated membranes (MAMs). The disruption of these contact sites has profound consequences for cellular function, such as imbalances of intracellular Ca(2+) signaling, cellular stress, and disrupted apoptosis progression. The promyelocytic leukemia (PML) protein has been previously recognized as a critical and essential regulator of multiple apoptotic response. Nevertheless, how PML would exert such broad and fundamental role in apoptosis remained for long time a mystery. In this review, we will discuss how recent results demonstrate that the elusive mechanism whereby the PML tumor suppressor exerts its essential role in apoptosis triggered by Ca(2+)-dependent stimuli can be attributed to its unexpected and fundamental role at MAMs in the control of the functional cross-talk between ER and mitochondria.


Asunto(s)
Apoptosis/fisiología , Leucemia Mieloide Aguda , Leucemia Promielocítica Aguda , Proteínas Nucleares/fisiología , Factores de Transcripción/fisiología , Proteínas Supresoras de Tumor/fisiología , Animales , Calcio/metabolismo , Señalización del Calcio , Retículo Endoplásmico/fisiología , Humanos , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patología , Leucemia Promielocítica Aguda/metabolismo , Leucemia Promielocítica Aguda/patología , Mitocondrias/fisiología , Proteína de la Leucemia Promielocítica , Transporte de Proteínas , Dedos de Zinc
17.
Anim Reprod Sci ; 123(1-2): 98-105, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21093994

RESUMEN

The sequence of vitellogenin A (VgA) and vitellogenin B (VgB) cDNAs in Atlantic bluefin tuna (Thunnus thynnus L.) were determined, and vitellogenin expression levels in the liver and oocyte yolk accumulation were compared in wild and captive-reared individuals. Liver and ovary samples were taken from 31 individuals reared experimentally in three commercial Atlantic bluefin tuna fattening sites in the Mediterranean Sea and from 33 wild individuals caught by commercial traps during the fish's migration towards their Mediterranean spawning grounds. The total length of VgA cDNA was 5585 nucleotides and that of VgB was 5267 nucleotides. The identity and similarity between deduced amino acid sequences of VgA and VgB were 60% and 78%, respectively. The Atlantic bluefin tuna VgA and VgB amino acid sequences have high similarities with those of other teleost fishes. Relative levels of VgA and VgB mRNAs were low in April, increased significantly during the reproductive period in May and June, and declined in July. There was a trend towards higher relative levels of VgA and VgB mRNAs in captive fish compared to wild individuals during the reproductive period. The surface occupied by eosinophilic yolk granules in fully vitellogenic oocytes, as well as the frequency of oocytes in late vitellogenesis, was significantly higher in captive compared to wild individuals. The study suggests that the experimental conditions under which Atlantic bluefin tuna individuals were reared allowed the occurrence of normal vitellogenesis, based on gene expression of VgA and VgB in the liver and yolk accumulation in the oocytes. The higher yolk accumulation and frequency of vitellogenic oocytes observed in the ovaries of captive fish suggest that improvements in feeding practices may result in an improved vitellogenic process.


Asunto(s)
Yema de Huevo/metabolismo , Hígado/metabolismo , Oocitos/metabolismo , Atún/genética , Vitelogeninas/genética , Animales , Animales Salvajes/genética , Animales Salvajes/metabolismo , Acuicultura , Clonación Molecular , Femenino , Expresión Génica , Atún/metabolismo , Vitelogeninas/biosíntesis , Vitelogeninas/metabolismo
19.
Int J Immunopathol Pharmacol ; 22(4): 967-78, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-20074460

RESUMEN

This study reports the immunomodulatory activity on human monocyte derived dendritic cells (MDDCs) of a vaccine preparation shown to be effective against an HPV16-related tumour in an animal model. The vaccine is composed of extract from Nicotiana benthamiana leaves containing HPV16 E7 protein expressed by a potato virus X-derived vector (NbPVX-E7). The effect of the extract was evaluated on MDDC differentiation and maturation by monitoring the phenotypic expression of specific markers. The results show that NbPVX-E7 does not induce monocyte differentiation to dendritic cells, but does induce MDDC maturation. Plant extract does not influence MDDC-uptake of E7-FITC while it significantly improves the Ovalbumin-FITC uptake, considered as a model antigen. Importantly, NbPVX-E7-pulsed MDDCs/PBMCs are able to prime human blood-derived lymphocytes from healthy individuals to induce HPV16 E7-specific cytotoxic activity. This is a propaedeutic study for a possible use of E7-containing plant extract in human immunotherapy of HPV-related lesions.


Asunto(s)
Adyuvantes Inmunológicos/farmacología , Células Dendríticas/inmunología , Linfocitos/inmunología , Nicotiana/metabolismo , Proteínas Oncogénicas Virales/inmunología , Vacunas contra Papillomavirus/inmunología , Extractos Vegetales/inmunología , Plantas Modificadas Genéticamente , Adyuvantes Inmunológicos/aislamiento & purificación , Presentación de Antígeno , Diferenciación Celular , Línea Celular Tumoral , Supervivencia Celular , Técnicas de Cocultivo , Citotoxicidad Inmunológica , Células Dendríticas/efectos de los fármacos , Células Dendríticas/metabolismo , Relación Dosis-Respuesta a Droga , Vectores Genéticos , Humanos , Activación de Linfocitos , Linfocitos/efectos de los fármacos , Masculino , Proteínas Oncogénicas Virales/biosíntesis , Proteínas Oncogénicas Virales/genética , Proteínas Oncogénicas Virales/aislamiento & purificación , Ovalbúmina/inmunología , Ovalbúmina/metabolismo , Proteínas E7 de Papillomavirus , Vacunas contra Papillomavirus/biosíntesis , Vacunas contra Papillomavirus/genética , Vacunas contra Papillomavirus/aislamiento & purificación , Extractos Vegetales/aislamiento & purificación , Hojas de la Planta , Potexvirus/genética , Proteínas Recombinantes/inmunología , Factores de Tiempo , Nicotiana/genética
20.
Oncogene ; 27(50): 6407-18, 2008 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-18955969

RESUMEN

There is a growing consensus that the various forms of cell death (necrosis, apoptosis and autophagy) are not separated by strict boundaries, but rather share molecular effectors and signaling routes. Among the latter, a clear role is played by calcium (Ca(2+)), the ubiquitous second messenger involved in the control of a broad variety of physiological events. Fine tuning of intracellular Ca(2+) homeostasis by anti- and proapoptotic proteins shapes the Ca(2+) signal to which mitochondria and other cellular effectors are exposed, and hence the efficiency of various cell death inducers. Here, we will review: (i) the evidence linking calcium homeostasis to the regulation of apoptotic, and more recently autophagic cell death, (ii) the discussion of mitochondria as a critical, although not unique checkpoint and (iii) the molecular and functional elucidation of ER/mitochondria contacts, corresponding to the mitochondria-associated membrane (MAM) subfraction and proposed to be a specialized signaling microdomain.


Asunto(s)
Apoptosis/fisiología , Calcio/fisiología , Retículo Endoplásmico/metabolismo , Animales , Calcio/metabolismo , Citosol/metabolismo , Humanos
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