Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 49
Filtrar
Más filtros

Banco de datos
Tipo del documento
Intervalo de año de publicación
1.
Ann Ig ; 36(3): 353-362, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38236000

RESUMEN

Background: A key renovation of doctoral programs is currently ongoing in Italy. Public health and its competencies may play a pivotal role in high-level training to scientific research, including interdisciplinary and methodological abilities. Methods: As a case study, we used the ongoing renovation of the Clinical and Experimental Medicine doctoral program at the University of Modena and Reggio Emilia. We focused on how the program is designed to meet national requirements as well as students' needs, thus improving educational standards for scientific research in the biomedical field, and on the specific contribution of public health and epidemiology in such an effort. Results: The renovation process of doctoral programs in Italy, with specific reference to the biomedical field, focuses on epidemiologic-statistical methodology, ethics, language and communication skills, and open science from an interdisciplinary and international perspective. In the specific context of the doctoral program assessed in the study and from a broader perspective, public health appears to play a key role, taking advantage of most recent methodological advancements, and contributing to the renovation of the learning process and its systematic quality monitoring. Conclusions: From a comparative assessment of this case study and Italian legislation, the key role of public health has emerged in the renovation process of doctoral programs in the biomedical field.


Asunto(s)
Investigación Biomédica , Médicos , Humanos , Salud Pública/educación , Estudiantes , Curriculum , Lenguaje
2.
Int J Mol Sci ; 22(19)2021 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-34638901

RESUMEN

Among the mechanisms leading to progression to Adult T-cell Leukaemia/Lymphoma in Human T-cell Leukaemia Virus type 1 (HTLV-1)-infected subjects, the contribution of stromal components remains poorly understood. To dissect the role of fibroblasts in HTLV-1-mediated lymphomagenesis, transcriptome studies, cytofluorimetric and qRT-PCR analyses of surface and intracellular markers linked to plasticity and stemness in coculture, and in vivo experiments were performed. A transcriptomic comparison between a more lymphomagenic (C91/III) and the parental (C91/PL) cell line evidenced hyperactivation of the PI3K/Akt pathway, confirmed by phospho-ELISA and 2-DE and WB analyses. C91/III cells also showed higher expression of mesenchymal and stemness genes. Short-term coculture with human foreskin fibroblasts (HFF) induced these features in C91/PL cells, and significantly increased not only the cancer stem cells (CSCs)-supporting CD10+GPR77+ HFF subpopulation, but also the percentage of ALDH1bright C91/PL cells. A non-cytotoxic acetylsalicylic acid treatment decreased HFF-induced ALDH1bright C91/PL cells, downregulated mesenchymal and stemness genes in cocultured cells, and delayed lymphoma growth in immunosuppressed mice, thus hindering the supportive activity of HFF on CSCs. These data suggest that crosstalk with HFF significantly intensifies the aggressiveness and plasticity of C91/PL cells, leading to the enrichment in lymphoma-initiating cells. Additional research is needed to better characterize these preliminary findings.


Asunto(s)
Fibroblastos/metabolismo , Perfilación de la Expresión Génica/métodos , Regulación Neoplásica de la Expresión Génica/genética , Linfoma/genética , Células Madre Neoplásicas/metabolismo , Animales , Antiinflamatorios no Esteroideos/farmacología , Aspirina/farmacología , Línea Celular , Células Cultivadas , Técnicas de Cocultivo , Fibroblastos/efectos de los fármacos , Fibroblastos/virología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Virus Linfotrópico T Tipo 1 Humano/fisiología , Humanos , Células Jurkat , Linfoma/tratamiento farmacológico , Linfoma/virología , Ratones Endogámicos NOD , Ratones Noqueados , Ratones SCID , Células Madre Neoplásicas/efectos de los fármacos , Células Madre Neoplásicas/virología , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Ensayos Antitumor por Modelo de Xenoinjerto/métodos
3.
J Cell Physiol ; 234(7): 11188-11199, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30565691

RESUMEN

Clusterin (CLU) is a chaperone-like protein with multiple functions. sCLU is frequently upregulated in prostate tumor cells after chemo- or radiotherapy and after surgical or pharmacological castration. Moreover, CLU has been documented to modulate the cellular homolog of murine thymoma virus akt8 oncogene (AKT) activity. Here, we investigated how CLU overexpression influences phosphatidylinositol 3'-kinase (PI3K)/AKT signaling in human normal and cancer epithelial prostate cells. Human prostate cells stably transfected with CLU were broadly profiled by reverse phase protein array (RPPA), with particular emphasis on the PI3K/AKT pathway. The effect of CLU overexpression on normal and cancer cell motility was also tested. Our results clearly indicate that CLU overexpression enhances phosphorylation of AKT restricted to isoform 2. Mechanistically, this can be explained by the finding that the phosphatase PH domain leucine-rich repeat-containing protein phosphatase 1 (PHLPP1), known to dephosphorylate AKT2 at S474, is markedly downregulated by CLU, whereas miR-190, a negative regulator of PHLPP1, is upregulated. Moreover, we found that phosphatase and tensin homolog (PTEN) was heavily phosphorylated at the inhibitory site S380, contributing to the hyperactivation of AKT signaling. By keeping AKT2 phosphorylation high, CLU dramatically enhances the migratory behavior of prostate epithelial cell lines with different migratory and invasive phenotypes, namely prostate normal epithelial 1A (PNT1A) and prostatic carcinoma 3 (PC3) cells. Altogether, our results unravel for the first time a circuit by which CLU can switch a low migration phenotype toward a high migration phenotype, through miR-190-dependent downmodulation of PHLPP1 expression and, in turn, stabilization of AKT2 phosphorylation.


Asunto(s)
Clusterina/metabolismo , Proteínas Nucleares/metabolismo , Fosfohidrolasa PTEN/metabolismo , Fosfoproteínas Fosfatasas/metabolismo , Neoplasias de la Próstata/patología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Células 3T3 , Animales , Línea Celular Tumoral , Movimiento Celular/fisiología , Clusterina/genética , Células Epiteliales/metabolismo , Regulación Neoplásica de la Expresión Génica/genética , Humanos , Masculino , Ratones , MicroARNs/genética , Células PC-3 , Fosfatidilinositol 3-Quinasas/metabolismo , Fosforilación , Próstata/patología , Proteínas Proto-Oncogénicas c-akt/genética , Transducción de Señal/genética
4.
Biochim Biophys Acta ; 1863(12): 2942-2976, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27612668

RESUMEN

Glycogen synthase kinase-3 (GSK-3) is a serine/threonine kinase that participates in an array of critical cellular processes. GSK-3 was first characterized as an enzyme that phosphorylated and inactivated glycogen synthase. However, subsequent studies have revealed that this moon-lighting protein is involved in numerous signaling pathways that regulate not only metabolism but also have roles in: apoptosis, cell cycle progression, cell renewal, differentiation, embryogenesis, migration, regulation of gene transcription, stem cell biology and survival. In this review, we will discuss the roles that GSK-3 plays in various diseases as well as how this pivotal kinase interacts with multiple signaling pathways such as: PI3K/PTEN/Akt/mTOR, Ras/Raf/MEK/ERK, Wnt/beta-catenin, hedgehog, Notch and TP53. Mutations that occur in these and other pathways can alter the effects that natural GSK-3 activity has on regulating these signaling circuits that can lead to cancer as well as other diseases. The novel roles that microRNAs play in regulation of the effects of GSK-3 will also be evaluated. Targeting GSK-3 and these other pathways may improve therapy and overcome therapeutic resistance.


Asunto(s)
Regulación Neoplásica de la Expresión Génica , Glucógeno Sintasa Quinasa 3/genética , MicroARNs/genética , Mutación , Neoplasias/genética , Animales , Diferenciación Celular , Proliferación Celular , Supervivencia Celular , Glucógeno Sintasa Quinasa 3/metabolismo , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Humanos , MicroARNs/metabolismo , Neoplasias/metabolismo , Neoplasias/patología , Fosfatidilinositol 3-Quinasas/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Receptores Notch/genética , Receptores Notch/metabolismo , Transducción de Señal , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Proteínas Wnt/genética , Proteínas Wnt/metabolismo , beta Catenina/genética , beta Catenina/metabolismo
5.
FASEB J ; 27(6): 2145-55, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23430973

RESUMEN

The serine/threonine kinase Akt/PKB is a major signaling hub integrating metabolic, survival, growth, and cell cycle regulatory signals. The definition of the phospho-motif cipher driving phosphorylation by Akt led to the identification of hundreds of putative substrates, and it is therefore pivotal to identify those whose phosphorylation by Akt is of consequence to biological processes. The Lmna gene products lamin A/C and the lamin A precursor prelamin A are type V intermediate filament proteins forming a filamentous meshwork, the lamina, underneath the inner nuclear membrane, for nuclear envelope structures organization and interphase chromatin anchoring. In our previous work, we reported that A-type lamins are phosphorylated by Akt at S301 and S404 in physiological conditions and are therefore bona fide substrates of Akt. We report here that Akt phosphorylation at S404 targets the precursor prelamin A for degradation. We further demonstrate that Akt also regulates Lmna transcription. Our study unveils a previously unknown function of Akt in the control of prelamin A stability and expression. Moreover, given the large number of diseases related to prelamin A, our findings represent a further important step bridging basic A-type lamin physiology to therapeutic approaches for lamin A-linked disorders.


Asunto(s)
Lamina Tipo A/genética , Proteínas Nucleares/metabolismo , Precursores de Proteínas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Animales , Línea Celular , Puntos de Control de la Fase G2 del Ciclo Celular , Regulación de la Expresión Génica , Células HEK293 , Humanos , Interfase , Ratones , Mitosis , Modelos Biológicos , Proteínas Nucleares/química , Fosforilación , Precursores de Proteínas/química , Proteolisis , Proteínas Proto-Oncogénicas c-akt/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-akt/genética , ARN Interferente Pequeño/genética , Transducción de Señal
6.
J Cell Physiol ; 228(6): 1323-31, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23169061

RESUMEN

Dystrophin is a subsarcolemmal protein that, by linking the actin cytoskeleton to the extracellular matrix via dystroglycans, is critical for the integrity of muscle fibers. Here, we report that epidermal melanocytes, obtained from conventional skin biopsy, express dystrophin with a restricted localization to the plasma membrane facing the dermal-epidermal junction. In addition the full-length muscle isoform mDp427 was clearly detectable in melanocyte cultures as assessed by immunohistochemistry, RNA, and Western blot analysis. Melanocytes of Duchenne muscular dystrophy (DMD) patients did not express dystrophin, and the ultrastructural analysis revealed typical mitochondrial alterations similar to those occurring in myoblasts from the same patients. Mitochondria of melanocytes from DMD patients readily accumulated tetramethylrhodamine methyl ester, indicating that they are energized irrespective of the presence of dystrophin but, at variance from mitochondria of control donors, depolarized upon the addition of oligomycin, suggesting that they are affected by a latent dysfunction unmasked by inhibition of the ATP synthase. Pure melanocyte cultures can be readily obtained by conventional skin biopsies and may be a feasible and reliable tool alternative to muscle biopsy for functional studies in dystrophinopathies. The mitochondrial dysfunction occurring in DMD melanocytes could represent a promising cellular biomarker for monitoring dystrophinopathies also in response to pharmacological treatments.


Asunto(s)
Distrofina/metabolismo , Melanocitos/metabolismo , Mitocondrias/metabolismo , Distrofia Muscular de Duchenne/metabolismo , Piel/metabolismo , Biopsia , Northern Blotting , Western Blotting , Estudios de Casos y Controles , Células Cultivadas , Distrofina/genética , Inhibidores Enzimáticos/farmacología , Regulación de la Expresión Génica , Humanos , Inmunohistoquímica , Queratinocitos/metabolismo , Melanocitos/efectos de los fármacos , Melanocitos/ultraestructura , Potencial de la Membrana Mitocondrial , Mitocondrias/efectos de los fármacos , Mitocondrias/ultraestructura , ATPasas de Translocación de Protón Mitocondriales/antagonistas & inhibidores , ATPasas de Translocación de Protón Mitocondriales/metabolismo , Distrofia Muscular de Duchenne/genética , Distrofia Muscular de Duchenne/patología , Mioblastos/metabolismo , Oligomicinas/farmacología , Rodaminas/metabolismo , Piel/efectos de los fármacos , Piel/ultraestructura , Factores de Tiempo , Utrofina/metabolismo
7.
Adv Biol Regul ; 89: 100974, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37245251

RESUMEN

Acute myeloid leukemia is a heterogeneous hematopoietic malignancy, characterized by uncontrolled clonal proliferation of abnormal myeloid progenitor cells, with poor outcomes. The internal tandem duplication (ITD) mutation of the Fms-like receptor tyrosine kinase 3 (FLT3) (FLT3-ITD) represents the most common genetic alteration in AML, detected in approximately 30% of AML patients, and is associated with high leukemic burden and poor prognosis. Therefore, this kinase has been regarded as an attractive druggable target for the treatment of FLT3-ITD AML, and selective small molecule inhibitors, such as quizartinib, have been identified and trialled. However, clinical outcomes have been disappointing so far due to poor remission rates, also because of acquired resistance. A strategy to overcome resistance is to combine FLT3 inhibitors with other targeted therapies. In this study, we investigated the preclinical efficacy of the combination of quizartinib with the pan PI3K inhibitor BAY-806946 in FLT3-ITD cell lines and primary cells from AML patients. We show here that BAY-806946 enhanced quizartinib cytotoxicity and, most importantly, that this combination increases the ability of quizartinib to kill CD34+ CD38-leukemia stem cells, whilst sparing normal hematopoietic stem cells. Because constitutively active FLT3 receptor tyrosine kinase is known to boost aberrant PI3K signaling, the increased sensitivity of primary cells to the above combination can be the mechanistic results of the disruption of signaling by vertical inhibition.


Asunto(s)
Leucemia Mieloide Aguda , Fosfatidilinositol 3-Quinasas , Humanos , Fosfatidilinositol 3-Quinasas/genética , Benzotiazoles/farmacología , Benzotiazoles/uso terapéutico , Mutación , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patología , Proteínas Tirosina Quinasas/genética , Proteínas Tirosina Quinasas/uso terapéutico , Tirosina Quinasa 3 Similar a fms/genética , Tirosina Quinasa 3 Similar a fms/uso terapéutico , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico
8.
Cell Death Dis ; 12(6): 573, 2021 06 03.
Artículo en Inglés | MEDLINE | ID: mdl-34083515

RESUMEN

Epigenomic dysregulation is a common pathological feature in human hematological malignancies. H3K9me3 emerges as an important epigenomic marker in acute myeloid leukemia (AML). Its associated methyltransferases, such as SETDB1, suppress AML leukemogenesis, whilst H3K9me3 demethylases KDM4C is required for mixed-lineage leukemia rearranged AML. However, the specific role and molecular mechanism of action of another member of the KDM4 family, KDM4A has not previously been clearly defined. In this study, we delineated and functionally validated the epigenomic network regulated by KDM4A. We show that selective loss of KDM4A is sufficient to induce apoptosis in a broad spectrum of human AML cells. This detrimental phenotype results from a global accumulation of H3K9me3 and H3K27me3 at KDM4A targeted genomic loci thereby causing downregulation of a KDM4A-PAF1 controlled transcriptional program essential for leukemogenesis, distinct from that of KDM4C. From this regulatory network, we further extracted a KDM4A-9 gene signature enriched with leukemia stem cell activity; the KDM4A-9 score alone or in combination with the known LSC17 score, effectively stratifies high-risk AML patients. Together, these results establish the essential and unique role of KDM4A for AML self-renewal and survival, supporting further investigation of KDM4A and its targets as a potential therapeutic vulnerability in AML.


Asunto(s)
Autorrenovación de las Células/genética , Supervivencia Celular/genética , Epigenómica/métodos , Histona Demetilasas/metabolismo , Leucemia Mieloide Aguda/genética , Animales , Apoptosis , Humanos , Ratones
9.
Adv Biol Regul ; 82: 100830, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34555701

RESUMEN

Acute myeloid leukemia (AML) is an aggressive hematopoietic malignancy, characterized by a heterogeneous genetic landscape and complex clonal evolution, with poor outcomes. Mutation at the internal tandem duplication of FLT3 (FLT3-ITD) is one of the most common somatic alterations in AML, associated with high relapse rates and poor survival due to the constitutive activation of the FLT3 receptor tyrosine kinase and its downstream effectors, such as PI3K signaling. Thus, aberrantly activated FLT3-kinase is regarded as an attractive target for therapy for this AML subtype, and a number of small molecule inhibitors of this kinase have been identified, some of which are approved for clinical practice. Nevertheless, acquired resistance to these molecules is often observed, leading to severe clinical outcomes. Therapeutic strategies to tackle resistance include combining FLT3 inhibitors with other antileukemic agents. Here, we report on the preclinical activity of the combination of the FLT3 inhibitor quizartinib with the dual PI3K/mTOR inhibitor PF-04691502 in FLT3-ITD cells. Briefly, we show that the association of these two molecules displays synergistic cytotoxicity in vitro in FLT3-ITD AML cells, triggering 90% cell death at nanomolar concentrations after 48 h.


Asunto(s)
Antineoplásicos , Leucemia Mieloide Aguda , Antineoplásicos/uso terapéutico , Línea Celular Tumoral , Humanos , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/genética , Mutación , Fosfatidilinositol 3-Quinasas/genética , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Serina-Treonina Quinasas TOR/genética , Tirosina Quinasa 3 Similar a fms/genética , Tirosina Quinasa 3 Similar a fms/uso terapéutico
10.
Pathogens ; 9(11)2020 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-33167340

RESUMEN

The US3 serine/threonine protein kinase is conserved among the alphaherpesvirus family and represents an important virulence factor. US3 plays a role in viral nuclear egress, induces dramatic alterations of the cytoskeleton, represses apoptosis, enhances gene expression and modulates the immune response. Although several substrates of US3 have been identified, an unbiased screen to identify US3 phosphorylation targets has not yet been described. Here, we perform a shotgun and phosphoproteomics analysis of cells expressing the US3 protein of pseudorabies virus (PRV) to identify US3 phosphorylation targets in an unbiased way. We identified several cellular proteins that are differentially phosphorylated upon US3 expression and validated the phosphorylation of lamin A/C at serine 404, both in US3-transfected and PRV-infected cells. These results provide new insights into the signaling network of the US3 protein kinase and may serve as a basis for future research into the role of the US3 protein in the viral replication cycle.

11.
J Clin Med ; 9(9)2020 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-32932888

RESUMEN

Acute myeloid leukemia (AML) is a highly heterogeneous hematopoietic malignancy characterized by excessive proliferation and accumulation of immature myeloid blasts in the bone marrow. AML has a very poor 5-year survival rate of just 16% in the UK; hence, more efficacious, tolerable, and targeted therapy is required. Persistent leukemia stem cell (LSC) populations underlie patient relapse and development of resistance to therapy. Identification of critical oncogenic signaling pathways in AML LSC may provide new avenues for novel therapeutic strategies. The phosphatidylinositol-3-kinase (PI3K)/Akt and the mammalian target of rapamycin (mTOR) signaling pathway, is often hyperactivated in AML, required to sustain the oncogenic potential of LSCs. Growing evidence suggests that targeting key components of this pathway may represent an effective treatment to kill AML LSCs. Despite this, accruing significant body of scientific knowledge, PI3K/Akt/mTOR inhibitors have not translated into clinical practice. In this article, we review the laboratory-based evidence of the critical role of PI3K/Akt/mTOR pathway in AML, and outcomes from current clinical studies using PI3K/Akt/mTOR inhibitors. Based on these results, we discuss the putative mechanisms of resistance to PI3K/Akt/mTOR inhibition, offering rationale for potential candidate combination therapies incorporating PI3K/Akt/mTOR inhibitors for precision medicine in AML.

12.
Biochim Biophys Acta Mol Cell Res ; 1867(9): 118731, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32360668

RESUMEN

Although the prognosis of patients with localized prostate cancer is good after surgery, with a favorable response to androgen deprivation therapy, about one third of them invariably relapse, and progress to castration-resistant prostate cancer. Overall, prostate cancer therapies remain scarcely effective, thus it is mandatory to devise alternative treatments enhancing the efficacy of surgical castration and hormone administration. Dysregulation of the phosphoinositide 3-kinase pathway has attracted growing attention in prostate cancer due to the highly frequent association of epigenetic and post-translational modifications as well as to genetic alterations of both phosphoinositide 3-kinase and PTEN to onset and/or progression of this malignancy, and to resistance to canonical androgen-deprivation therapy. Here we provide a summary of the biological functions of the major players of this cascade and their deregulation in prostate cancer, summarizing the results of preclinical and clinical studies with PI3K signaling inhibitors and the reasons of failure independent from genomic changes.


Asunto(s)
Fosfohidrolasa PTEN/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Neoplasias de la Próstata/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal , Animales , Biomarcadores , Línea Celular Tumoral , Humanos , Masculino , Terapia Molecular Dirigida , Fosfohidrolasa PTEN/genética , Fosfatidilinositol 3-Quinasas/genética , Inhibidores de las Quinasa Fosfoinosítidos-3/farmacología , Inhibidores de las Quinasa Fosfoinosítidos-3/uso terapéutico , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/etiología , Neoplasias de la Próstata/patología , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Serina-Treonina Quinasas TOR/metabolismo , Resultado del Tratamiento
13.
Biochim Biophys Acta Mol Cell Res ; 1867(4): 118635, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31884070

RESUMEN

The introduction of therapeutics targeting specific tumor-promoting oncogenic or non-oncogenic signaling pathways has revolutionized cancer treatment. Mechanistic (previously mammalian) target of rapamycin (mTOR), a highly conserved Ser/Thr kinase, is a central hub of the phosphatidylinositol 3-kinase (PI3K)/Akt/mTOR network, one of the most frequently deregulated signaling pathways in cancer, that makes it an attractive target for therapy. Numerous mTOR inhibitors have progressed to clinical trials and two of them have been officially approved as anticancer therapeutics. However, mTOR-targeting drugs have met with a very limited success in cancer patients. Frequently, the primary impediment to a successful targeted therapy in cancer is drug-resistance, either from the very beginning of the therapy (innate resistance) or after an initial response and upon repeated drug treatment (evasive or acquired resistance). Drug-resistance leads to treatment failure and relapse/progression of the disease. Resistance to mTOR inhibitors depends, among other reasons, on activation/deactivation of several signaling pathways, included those regulated by glycogen synthase kinase-3 (GSK3), a protein that targets a vast number of substrates in its repertoire, thereby orchestrating many processes that include cell proliferation and survival, metabolism, differentiation, and stemness. A detailed knowledge of the rewiring of signaling pathways triggered by exposure to mTOR inhibitors is critical to our understanding of the consequences such perturbations cause in tumors, including the emergence of drug-resistant cells. Here, we provide the reader with an updated overview of intricate circuitries that connect mTOR and GSK3 and we relate them to the efficacy (or lack of efficacy) of mTOR inhibitors in cancer cells.


Asunto(s)
Antineoplásicos/uso terapéutico , Glucógeno Sintasa Quinasa 3/metabolismo , Neoplasias/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/uso terapéutico , Transducción de Señal , Serina-Treonina Quinasas TOR/metabolismo , Animales , Antineoplásicos/farmacología , Glucógeno Sintasa Quinasa 3/antagonistas & inhibidores , Humanos , Neoplasias/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Serina-Treonina Quinasas TOR/antagonistas & inhibidores
14.
J Cell Physiol ; 220(3): 553-61, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19479937

RESUMEN

Lamin A/C is a nuclear lamina constituent mutated in a number of human inherited disorders collectively referred to as laminopathies. The occurrence and significance of lamin A/C interplay with signaling molecules is an old question, suggested by pioneer studies performed in vitro. However, this relevant question has remained substantially unanswered, until data obtained in cellular and organismal models of laminopathies have indicated two main aspects of lamin A function. The first aspect is that lamins establish functional interactions with different protein platforms, the second aspect is that lamin A/C activity and altered function may elicit different effects in different cells and tissue types and even in different districts of the same tissue. Both these observations strongly suggest that signaling mechanisms targeting lamin A/C or its binding partners may regulate such a plastic behavior. A number of very recent data show involvement of kinases, as Akt and Erk, or phosphatases, as PP1 and PP2, in lamin A-linked cellular mechanisms. Moreover, altered activation of signaling in laminopathies and rescue of the pathological phenotype in animal models by inhibitors of signaling pathways, strongly suggest that signaling effectors related to lamin A/C may be implicated in the pathogenesis of laminopathies and may represent targets of therapeutic intervention. In face of such an open perspective of basic and applied research, we review current evidence of lamin A/C interplay with signaling molecules, with particular emphasis on the lamin A-Akt interaction and on the biological significance of their relationship.


Asunto(s)
Lamina Tipo A/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal , Animales , Modelos Animales de Enfermedad , Humanos , Lamina Tipo A/genética , Mutación , Unión Proteica , Transducción de Señal/genética
15.
Reprod Biomed Online ; 18(2): 226-34, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19192343

RESUMEN

MATER (Maternal Antigen That Embryos Require) is an oocyte-specific protein dependent on the maternal genome and required for early embryonic development. The gene products expressed in oocytes play important roles in folliculogenesis, fertilization and pre-implantation development. The aim of this study was to characterize the localization and distribution pattern of the human MATER protein during follicular development and after ovulation, to determine its functional role. Immunocytochemistry experiments coupled with confocal and electron microscopy analysis were carried out to determine the ultrastructural localization of MATER in human ovarian tissue and in isolated oocytes, obtained during IVF procedures. Human cumulus cells were cultured, with or without cycloheximide, to confirm endogenous biosynthesis of the protein. Human MATER is detectable at the onset of the follicular maturation process, suggesting this protein has a role at earlier stages in the human compared with other mammalian species. The presence of MATER is specific to the oocyte and follicular cells that, during maturation, are spatially and functionally associated with the oocyte. The nuclear, nucleolar and mitochondrial localization hints at a possible role in RNA processing and the metabolic activity of the cell.


Asunto(s)
Autoantígenos/metabolismo , Células de la Granulosa/metabolismo , Oocitos/metabolismo , Células Tecales/metabolismo , Nucléolo Celular/metabolismo , Núcleo Celular/metabolismo , Células Cultivadas , Femenino , Células de la Granulosa/citología , Humanos , Microscopía Confocal , Mitocondrias/metabolismo , Proteínas Mitocondriales , Proteínas Nucleares , Oocitos/citología , Folículo Ovárico/citología , Folículo Ovárico/ultraestructura , Procesamiento Postranscripcional del ARN/fisiología , Células Tecales/citología , Distribución Tisular
16.
Neurotoxicology ; 75: 209-220, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31585128

RESUMEN

Impairment of the axonal transport system mediated by intracellular microtubules (MTs) is known to be a major drawback in neurodegenerative processes. Due to a growing interest on the neurotoxic effects of selenium in environmental health, our study aimed to assess the relationship between selenium and MTs perturbation, that may favour disease onset over a genetic predisposition to amyotrophic lateral sclerosis. We treated a neuron-like cell line with sodium selenite, sodium selenate and seleno-methionine and observed that the whole cytoskeleton was affected. We then investigated the protein interactome of cells overexpressing αTubulin-4A (TUBA4A) and found that selenium increases the interaction of TUBA4A with DNA- and RNA-binding proteins. TUBA4A ubiquitination and glutathionylation were also observed, possibly due to a selenium-dependent increase of ROS, leading to perturbation and degradation of MTs. Remarkably, the TUBA4A mutants R320C and A383 T, previously described in ALS patients, showed the same post-translational modifications to a similar extent. In conclusion this study gives insights into a specific mechanism characterizing selenium neurotoxicity.


Asunto(s)
Esclerosis Amiotrófica Lateral/metabolismo , Microtúbulos/efectos de los fármacos , Neuronas/efectos de los fármacos , Selenio/toxicidad , Esclerosis Amiotrófica Lateral/etiología , Western Blotting , Línea Celular Tumoral , Técnica del Anticuerpo Fluorescente , Células HEK293 , Humanos , Inmunoprecipitación , Microscopía Confocal , Microtúbulos/metabolismo , Neuronas/metabolismo , Neuronas/ultraestructura , Especies Reactivas de Oxígeno/metabolismo , Tubulina (Proteína)/metabolismo
17.
Mater Sci Eng C Mater Biol Appl ; 96: 153-165, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30606521

RESUMEN

The need for new approaches to investigate ex vivo the causes and effects of tumor and to achieve improved cancer treatments and medical therapies is particularly urgent for malignant pathologies such as lymphomas and leukemias, whose tissue initiator cells interact with the stroma creating a three-dimensional (3D) protective environment that conventional mono- and bi-dimensional (2D) models are not able to simulate realistically. The solvent-casting particulate leaching (SCPL) technique, that is already a standard method to produce polymer-based scaffolds for bone tissue repair, is proposed here to fabricate innovative 3D porous structures to mimic the bone marrow niche in vitro. Two different polymers, namely a rigid polymethyl methacrylate (PMMA) and a flexible polyurethane (PU), were evaluated to the purpose, whereas NaCl, in the form of common salt table, resulted to be an efficient porogen. The adoption of an appropriate polymer-to-salt ratio, experimentally defined as 1:4 for both PMMA and PU, gave place to a rich and interconnected porosity, ranging between 82.1 vol% and 91.3 vol%, and the choice of admixing fine-grained or coarse-grained salt powders allowed to control the final pore size. The mechanical properties under compression load were affected both by the polymer matrix and by the scaffold's architecture, with values of the elastic modulus indicatively varying between 29 kPa and 1283 kPa. Preliminary tests performed with human stromal HS-5 cells co-cultured with leukemic cells allowed us to conclude that stromal cells grown associated to the supports keep their well-known protective and pro-survival effect on cancer cells, indicating that these devices can be very useful to mimic the bone marrow microenvironment and therefore to assess the efficacy of novel therapies in pre-clinical studies.


Asunto(s)
Células de la Médula Ósea/metabolismo , Matriz Ósea/química , Microambiente Celular , Andamios del Tejido/química , Células de la Médula Ósea/citología , Técnicas de Cocultivo , Módulo de Elasticidad , Humanos , Células Jurkat , Polimetil Metacrilato/química , Poliuretanos/química , Células del Estroma/citología , Células del Estroma/metabolismo
18.
Aging (Albany NY) ; 10(10): 2911-2934, 2018 10 24.
Artículo en Inglés | MEDLINE | ID: mdl-30362963

RESUMEN

Mesenchymal stem cells have emerged as an important tool that can be used for tissue regeneration thanks to their easy preparation, differentiation potential and immunomodulatory activity. However, an extensive culture of stem cells in vitro prior to clinical use can lead to oxidative stress that can modulate different stem cells properties, such as self-renewal, proliferation, differentiation and senescence. The aim of this study was to investigate the aging process occurring during in vitro expansion of stem cells, obtained from amniotic fluids (AFSC) at similar gestational age.The analysis of 21 AFSC samples allowed to classify them in groups with different levels of stemness properties. In summary, the expression of pluripotency genes and the proliferation rate were inversely correlated with the content of reactive oxygen species (ROS), DNA damage signs and the onset premature aging markers, including accumulation of prelamin A, the lamin A immature form. Interestingly, a specific source of ROS, the NADPH oxidase isoform 4 (Nox4), can localize into PML nuclear bodies (PML-NB), where it associates to prelamin A. Besides, Nox4 post translational modification, involved in PML-NB localization, is linked to its degradation pathway, as it is also for prelamin A, thus possibly modulating the premature aging phenotype occurrence.


Asunto(s)
Líquido Amniótico/citología , Núcleo Celular/enzimología , Senescencia Celular , Lamina Tipo A/metabolismo , Células Madre Mesenquimatosas/enzimología , NADPH Oxidasa 4/metabolismo , Estrés Oxidativo , Adulto , Núcleo Celular/genética , Proliferación Celular , Células Cultivadas , Senescencia Celular/genética , Femenino , Regulación de la Expresión Génica , Humanos , Oxidación-Reducción , Fenotipo , Embarazo , Transducción de Señal
19.
Adv Biol Regul ; 68: 2-9, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29576448

RESUMEN

A main cause of treatment failure for AML patients is resistance to chemotherapy. Survival of AML cells may depend on mechanisms that elude conventional drugs action and/or on the presence of leukemia initiating cells at diagnosis, and their persistence after therapy. MDR1 gene is an ATP-dependent drug efflux pump known to be a risk factor for the emergence of resistance, when combined to unstable cytogenetic profile of AML patients. In the present study, we analyzed the sensitivity to conventional chemotherapeutic drugs of 26 samples of primary blasts collected from AML patients at diagnosis. Detection of cell viability and apoptosis allowed to identify two group of samples, one resistant and one sensitive to in vitro treatment. The cells were then analyzed for the presence and the activity of P-glycoprotein. A comparative analysis showed that resistant samples exhibited a high level of MDR1 mRNA as well as of P-glycoprotein content and activity. Moreover, they also displayed high PI3K signaling. Therefore, we checked whether the association with signaling inhibitors might resensitize resistant samples to chemo-drugs. The combination showed a very potent cytotoxic effect, possibly through down modulation of MDR1, which was maintained also when primary blasts were co-cultured with human stromal cells. Remarkably, dual PI3K/mTOR inactivation was cytotoxic also to leukemia initiating cells. All together, our findings indicate that signaling activation profiling associated to gene expression can be very useful to stratify patients and improve therapy.


Asunto(s)
Leucemia Mieloide Aguda/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Serina-Treonina Quinasas TOR/metabolismo , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Citarabina/farmacología , Etopósido/farmacología , Humanos , Transducción de Señal/efectos de los fármacos
20.
Adv Biol Regul ; 64: 1-8, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28373060

RESUMEN

CK2 and AKT display a high degree of cross-regulation of their respective functions, both directly, through physical interaction and phosphorylation, and indirectly, through an intense cross-talk of key downstream effectors, ultimately leading to sustained AKT activation. Being CK2 and AKT attractive targets for therapeutic intervention, here we would like to emphasize how AKT and CK2 might influence cell fate through their complex isoform-specific and contextual-dependent cross-talk, to the extent that such functional interplay should be considered when devising therapies that target one or both these key signaling kinases.


Asunto(s)
Quinasa de la Caseína II/genética , Regulación Neoplásica de la Expresión Génica , Neoplasias/genética , Proteínas Proto-Oncogénicas c-akt/genética , Transducción de Señal/genética , Animales , Antineoplásicos/uso terapéutico , Quinasa de la Caseína II/antagonistas & inhibidores , Quinasa de la Caseína II/metabolismo , Humanos , Terapia Molecular Dirigida , Neoplasias/tratamiento farmacológico , Neoplasias/enzimología , Neoplasias/patología , Fosforilación/efectos de los fármacos , Isoformas de Proteínas/antagonistas & inhibidores , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Inhibidores de Proteínas Quinasas/uso terapéutico , Proteínas Proto-Oncogénicas c-akt/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-akt/metabolismo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA