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2.
Stem Cells ; 34(5): 1332-42, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-26850087

RESUMEN

Peribiliary glands (PBGs) are niches in the biliary tree and containing heterogeneous endodermal stem/progenitors cells that can differentiate, in vitro and in vivo, toward pancreatic islets. The aim of this study was to evaluate, in experimental and human diabetes, proliferation of cells in PBGs and differentiation of the biliary tree stem/progenitor cells (BTSCs) toward insulin-producing cells. Diabetes was generated in mice by intraperitoneal injection of a single dose of 200 mg/kg (N = 12) or 120 mg/kg (N = 12) of streptozotocin. Liver, pancreas, and extrahepatic biliary trees were en bloc dissected and examined. Cells in PBGs proliferated in experimental diabetes, and their proliferation was greatest in the PBGs of the hepatopancreatic ampulla, and inversely correlated with the pancreatic islet area. In rodents, the cell proliferation in PBGs was characterized by the expansion of Sox9-positive stem/progenitor cells that gave rise to insulin-producing cells. Insulin-producing cells were located mostly in PBGs in the portion of the biliary tree closest to the duodenum, and their appearance was associated with upregulation of MafA and Gli1 gene expression. In patients with type 2 diabetes, PBGs at the level of the hepatopancreatic ampulla contained cells showing signs of proliferation and pancreatic fate commitment. In vitro, high glucose concentrations induced the differentiation of human BTSCs cultures toward pancreatic beta cell fates. The cells in PBGs respond to diabetes with proliferation and differentiation towards insulin-producing cells indicating that PBG niches may rescue pancreatic islet impairment in diabetes. These findings offer important implications for the pathophysiology and complications of this disease. Stem Cells 2016;34:1332-1342.


Asunto(s)
Sistema Biliar/citología , Diabetes Mellitus Experimental/patología , Diabetes Mellitus Tipo 2/patología , Células Secretoras de Insulina/citología , Nicho de Células Madre , Células Madre/citología , Animales , Compartimento Celular , Diferenciación Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Glucosa/farmacología , Humanos , Insulina/metabolismo , Masculino , Ratones Endogámicos C57BL , Estreptozocina
3.
Cancer Invest ; 32(1): 13-21, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24380379

RESUMEN

Fetal lung adenocarcinoma (FLAC) is a rare variant of lung adenocarcinoma. Studies regarding FLAC have been based only on histopathological observations, thus representative in vitro models of FLAC cultures are unavailable. We have established and characterized a human primary FLAC cell culture, exploring its biology, chemosensitivity, and migration. FLAC cells and specimen showed significant upregulation of VEGF165 and HIF-1α mRNA levels. This observation was confirmed by in vitro chemosensitivity and migration assay, showing that only Axitinib was comparable to Cisplatin treatment. We provide a suitable in vitro model to further investigate the nature of this rare type of cancer.


Asunto(s)
Adenocarcinoma/patología , Antineoplásicos/farmacología , Movimiento Celular/efectos de los fármacos , Imidazoles/farmacología , Indazoles/farmacología , Neoplasias Pulmonares/patología , Inhibidores de Proteínas Quinasas/farmacología , Adenocarcinoma/diagnóstico por imagen , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adenocarcinoma del Pulmón , Anciano de 80 o más Años , Axitinib , Supervivencia Celular/efectos de los fármacos , Cisplatino/farmacología , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Persona de Mediana Edad , Invasividad Neoplásica , ARN Mensajero/metabolismo , Radiografía , Células Tumorales Cultivadas , Regulación hacia Arriba , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/metabolismo
4.
Acta Psychol (Amst) ; 244: 104175, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38359654

RESUMEN

In many countries, early mathematical learning takes place in informal and play-based situations. To support children's mathematical learning, the interactions that occur in the daily contact between the early childhood (EC) teacher and the child in kindergarten play an important role. In these interactions, the feedback provided by the EC teacher is considered to have effects on learning. However, how EC teachers actually give specific or non-specific feedback in everyday activities and play situations with a potential for mathematical learning (natural mathematical learning situations) has been little studied so far. To comprehensively characterize the EC teacher's feedback in natural mathematical learning situations, the current study developed a detailed category system based on categories from previous feedback studies, conducted under various conditions and with different objectives. To verify our category system, we coded mathematical teacher-child interactions (N = 162). The coding provided us with evidence that the category system allows to capture the given feedback in natural mathematical learning situations reliably and in detail. The category system can be useful for further research examining the effects of naturally given feedback on children's mathematical learning and, in the long run, for training teachers in the use of potentially supportive feedback in natural learning situations.


Asunto(s)
Aprendizaje , Instituciones Académicas , Humanos , Preescolar , Retroalimentación
5.
J Clin Med ; 13(9)2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38731081

RESUMEN

Background: Guselkumab is the first approved human IgG1λ monoclonal antibody selectively targeting the p19 subunit of IL23. Its effectiveness and safety were widely reported by clinical trials. However, these results must be confirmed in real life since its safety deals with more complicated subjects with respect to trials. Currently, real-life data on the use of guselkumab following treatment failure with ustekinumab are limited, and existing studies usually show a small cohort and/or a reduced follow-up period. In this context, the aim of our study was to evaluate the use of guselkumab in patients who previously did not respond to ustekinumab after up to 3 years of treatment. Methods: A multicenter retrospective study was performed. The study enrolled patients affected by moderate-to-severe plaque psoriasis undergoing treatment with guselkumab who were attending the Psoriasis Center of nine different centers in the Campania region of Italy. Demographic and clinical features were collected for each patient at baseline. Moreover, data on psoriasis severity and adverse events (AEs) were collected at each follow-up visit (week (W)16-W36-W52-W104-W156). Results: A total of 112 patients (70 male, 62.5%; mean age 54.8 ± 11.7 years old) were enrolled. Of these, 48 (42.9%), 34 (30.4%), and 16 (14.3%) reached 1, 2, and 3 years, respectively, of follow-up under guselkumab. A statistically significant clinical improvement was observed since W16, and sustained effectiveness was reported at each timepoint up to W156. No serious AEs were collected. Moreover, a sub analysis on the body mass index, involvement of difficult-to-treat areas, and presence of psoriatic arthritis (PsA) showed that the presence of PsA or palmoplantar psoriasis was associated with a reduced clinical improvement at W16 and W36, without differences from W52. In contrast, the efficacy of guselkumab does not seem to be affected by the BMI, involvement of fingernails, or location in the genital or scalp area. Conclusions: To sum up, our long-term real-life multicenter retrospective study confirmed the efficacy and safety of guselkumab following ustekinumab discontinuation up to 156 weeks of treatment.

6.
Cell Tissue Bank ; 14(2): 277-87, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22820760

RESUMEN

Good manufacturing practices guidelines require safer and standardized cell substrates especially for those cell therapy products to treat ocular diseases where fibroblasts are used as feeder layers. However, if these are unavailable for stem cells culturing, murine fibroblasts are regularly used, raising critical issues as accidentally transplanting xenogenous graft and adversely affecting stem cell clinical trials. Moreover, human fibroblasts play a significant role in testing novel ophthalmologic drugs. Accordingly, we developed a standardized laboratory and surgical approach to isolate normal and undamaged Tenon's fibroblasts to implement the setting up of banks for both stem cells-based ocular cell therapy and in vitro drug testing. A 2-3 cm(2) undamaged Tenon's biopsy was surgically obtained from 28 patients without mutually correlated ocular diseases. Nineteen dermal biopsies were used as control. Fibroblasts were isolated with or without collagenase, cultured in autologous, fetal bovine or AB serum, tested for viability by trypan blue, vimentin expression and standardized until passage 6. Successful Tenon's fibroblasts isolation was age dependent (P = 0.001) but not sex, pathology or surgery related. A significant rate of successful cultures were obtained when biopsies were not digested by collagenase (P = 0.013). Moreover, cultures in autologous or fetal bovine serum had comparable proliferative properties (P = 0.77; P = 0.82). Through our surgical and laboratory standardized procedure, we elucidated for the first time key points of this human primary culture system, the role of the autologous serum, comparing Tenon's and dermal fibroblasts. Our protocol may be clinically useful to reduce the risk above mentioned and may be potentially more effective for ophthalmological clinical purposes.


Asunto(s)
Proliferación Celular , Separación Celular/métodos , Fibroblastos/patología , Cápsula de Tenon/patología , Bancos de Tejidos , Factores de Edad , Biopsia , Proliferación Celular/efectos de los fármacos , Tratamiento Basado en Trasplante de Células y Tejidos , Células Cultivadas , Medios de Cultivo Condicionados/farmacología , Dermis/efectos de los fármacos , Dermis/patología , Oftalmopatías/terapia , Fibroblastos/efectos de los fármacos , Humanos , Técnicas In Vitro , Factores Sexuales
7.
Int J Cancer ; 131(4): E562-8, 2012 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-21932419

RESUMEN

Activated p53 is necessary for tumor suppression. Homeodomain-interacting protein kinase-2 (HIPK2) is a positive regulator of functional p53. HIPK2 modulates wild-type p53 activity toward proapoptotic transcription and tumor suppression by the phosphorylation of serine 46. Knock-down of HIPK2 interferes with tumor suppression and sensitivity to chemotherapy. Combined administration of adriamycin and zinc restores activity of misfolded p53 and enables the induction of its proapoptotic and tumor suppressor functions in vitro and in vivo. We therefore looked for a cancer model where HIPK2 expression is low. MMTV-neu transgenic mice overexpressing HER2/neu, develop mammary tumors at puberty with a long latency, showing very low expression of HIPK2. Here we show that whereas these tumors are resistant to adriamycin treatment, a combination of adriamycin and zinc suppresses tumor growth in vivo in these mice, an effect evidenced by the histological features of the mammary tumors. The combined treatment of adriamycin and zinc also restores wild-type p53 conformation and induces proapoptotic transcription activity. These findings may open up new possibilities for the treatment of human cancers via the combination of zinc with chemotherapeutic agents, for a selected group of patients expressing low levels of HIPK2, with an intact p53. In addition, HIPK2 may serve as a new biomarker for tumor aggressiveness.


Asunto(s)
Antineoplásicos/uso terapéutico , Doxorrubicina/uso terapéutico , Neoplasias Mamarias Experimentales/tratamiento farmacológico , Proteína p53 Supresora de Tumor/fisiología , Zinc/administración & dosificación , Animales , Apoptosis , Secuencia de Bases , Cartilla de ADN , Genes erbB-2 , Neoplasias Mamarias Experimentales/virología , Virus del Tumor Mamario del Ratón/aislamiento & purificación , Ratones , Ratones Transgénicos , Pliegue de Proteína , Reacción en Cadena en Tiempo Real de la Polimerasa , Proteína p53 Supresora de Tumor/metabolismo
8.
PLoS One ; 17(6): e0270116, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35771852

RESUMEN

A motivational downturn in mathematics during secondary school has been well documented for many students. As a way to address this, creating personally relevant tasks is supposed to increase students' motivation for mathematical tasks. According to recent research, topics relating to affiliation, achievement, and power are personally relevant for young people. Prior research showed that motive imagery in school tasks increases students' task-related intrinsic value and success expectancies. The present study examined the effect of motive topics in word problems on students' task performance. We contextualized mathematical tasks either with affiliation, achievement, and power topics or with neutral topics not related to motive topics. The tasks were comparable regarding their mean word count, text, and mathematical complexity. In three experimental studies (N1 = 56, N2 = 63, N3 = 62), the students solved four tasks for each motive topic and neutral tasks, respectively. The dependent variables were task performance, intrinsic values, and expectancies of success. Repeated measures analyses of variance with the four-level, within-subjects factor motive imagery revealed positive effects of motive imagery in word problems on students' task performance. This was particularly true for achievement-related tasks compared with neutral tasks. The results also indicated slightly positive effects for affiliation-related word problems on students' performance. In addition, the intrinsic value for affiliation-related (Experiment 1) and achievement-related tasks (Experiment 3) was higher than for neutral tasks. Power imagery did not affect students' task performance; it negatively affected students' intrinsic value compared with neutral tasks. Task-related success expectancies were not influenced by motive imagery. The present study replicates and extends previous findings that indicate that tasks referring to affiliation and achievement imagery are more appealing to students and can benefit their performance.


Asunto(s)
Logro , Análisis y Desempeño de Tareas , Adolescente , Humanos , Matemática , Motivación , Estudiantes
9.
Ital J Dermatol Venerol ; 157(5): 436-440, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35785926

RESUMEN

BACKGROUND: Psoriatic arthritis (PsA) is a chronic inflammatory disease that can produce disabling joint symptoms, adding significantly to the physical and psychosocial burden of psoriasis. Early detection is important to allow the development of an appropriate care plan to delay the onset of PsA and maximize the patient's quality of life. Our aim was to present the criteria, based on evidence and expert opinion, for a multidisciplinary approach to the management of PsA in a patient already characterized by skin manifestation. METHODS: An expert panel from the principal psoriatic care units of the Campania region of Italy met to discuss their mutual experience of the multidisciplinary approach to the management of psoriatic disease and to describe an integrated dermatologic/rheumatologic approach focused on the early diagnosis, management, and treatment of PsA. RESULTS: Two types of consultation modalities were considered most relevant to the care of patients with psoriatic disease in Italy: the parallel approach and the face-to-face care unit approach. Screening criteria for multidisciplinary care unit admission were described, with dermatologists, as the primary managers of the majority of patients with psoriasis, playing a critical role in introducing patients early on to therapy. CONCLUSIONS: An integrated management approach may enhance patient care by ensuring early diagnosis and treatment, with the potential to achieve better outcomes for both skin and musculoskeletal manifestations of psoriasis. The multidisciplinary care unit model is an effective and satisfying collaborative approach, not only optimizing outcomes and satisfaction for the patient but strengthening collaboration between the specialties.


Asunto(s)
Artritis Psoriásica , Psoriasis , Artritis Psoriásica/diagnóstico , Diagnóstico Precoz , Humanos , Estudios Interdisciplinarios , Psoriasis/diagnóstico , Calidad de Vida
10.
Artículo en Inglés | MEDLINE | ID: mdl-35206248

RESUMEN

The literature reported higher depression rates in psoriasis patients compared to the general population. Our study aimed to verify whether variability in depression prevalence was due to using different diagnostic tools. We also aimed to determine whether dysfunctional coping strategies might increase the depression burden. We assessed psoriasis severity by the Psoriasis Area Severity Index (PASI) and PSOdisk. We analyzed mental alterations of 120 outpatients by Hamilton Depression and Anxiety Rating Scales (HAM-D and HAM-A), Symptom Checklist-90-Revised (SCL-90-R), plus coping strategies and quality of life by Coping Orientation to Problems Experienced (COPE) Inventory and 36-Item Short Form Health Survey (SF-36). We divided our cohort into five subgroups from minimal to severe psoriasis using the PSOdisk total score. Depression prevalence varied according to the assessment criteria for specificity, frequency, and severity. Different mood disorders other than major depression emerged when we used DSM-IV-TR criteria. Correlation analysis of the criteria we used to diagnose depression or depressed mood indicated that a dysfunctional coping strategy was highly and positively correlated only in patients of the severe subgroup. Differently, a negative correlation emerged between the SF-36 Mental Summary Component (MSC) and behavioral disengagement, thus suggesting that psychopathological distress might induce patients with a marked/severe psoriasis to adopt dysfunctional coping strategies. Dermatologists are fundamental in detecting comorbid depression, referring psoriasis patients to mental health specialists to achieve adequate treatments, and preventing suicide risk.


Asunto(s)
Trastorno Depresivo Mayor , Psoriasis , Estudios de Cohortes , Depresión/epidemiología , Humanos , Análisis Multivariante , Prevalencia , Psoriasis/complicaciones , Psoriasis/epidemiología , Calidad de Vida , Índice de Severidad de la Enfermedad
11.
Pharmaceutics ; 13(10)2021 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-34683927

RESUMEN

The study focused on the development and characterization of an O/W emulsion for skincare containing Castanea sativa spiny burs extract (CSE) as functional agent. The emulsion was stable and had suitable physicochemical and technological properties for dermal application and CSE showed no cytotoxicity in spontaneously immortalized keratinocytes (HaCaT) at active concentrations. A single-blind, placebo-controlled, monocentric study was designed to evaluate the skin tolerability and the skin performance of the CSE-loaded emulsion on healthy human volunteers. An improvement was observed in skin biomechanical properties such as hydration, skin elasticity and a reduction in the periorbital wrinkles in 30 days without altering the skin barrier function, sebum, pH, and erythema values. A significant skin moisturizing effect was detected while the skin barrier function was preserved. The selected natural ingredient combined with the designed formulation and the optimized preparation method has led to a final product that satisfies the physico-chemical and technological requirements underlying the safety of use and the formulative stability over time. With no negative skin reactions and highly significant effects on skin elasticity, wrinkles, and moisturization, the CSE-based emulsion achieved very satisfying outcomes representing a promising functional formulation for skin care.

12.
Biochim Biophys Acta ; 1793(2): 368-77, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19046997

RESUMEN

HIPK2 has been implicated in restraining tumor progression by more than one mechanism, involving both its catalytic and transcriptional co-repressor functions. Starting from the finding that HIPK2 knockdown by RNA-interference (HIPK2i) induced significant up-regulation of HIF-1alpha mRNA and of its target VEGF in tumor cells, we evaluated the role of HIPK2 in transcriptional regulation of HIF-1alpha. We found that HIPK2 overexpression downmodulated both HIF-1alpha reporter activity and mRNA levels and showed that HIPK2 was bound in vivo to the HIF-1alpha promoter likely in a multiprotein co-repressor complex with histone deacetylase 1 (HDAC1). Thus, the HIF-1alpha promoter was strongly acetylated following HIPK2 knockdown. The HIF-1alpha-dependent VEGF transcription was evaluated by co-transfection of a dominant negative (DN) construct of HIF-1alpha that inhibited VEGF reporter activity induced by HIPK2 knockdown. HIF-1alpha and VEGF up-regulation in HIPK2i cells correlated with increased vascularity of tumor xenografts in vivo and tube formation in HUVEC in vitro. These findings provide the first evidence of HIPK2-mediated transcriptional regulation of HIF-1alpha that might play a critical role in VEGF expression.


Asunto(s)
Proteínas Portadoras/metabolismo , Regulación Neoplásica de la Expresión Génica , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Neoplasias/genética , Neoplasias/patología , Proteínas Serina-Treonina Quinasas/metabolismo , Transcripción Genética , Animales , Línea Celular Tumoral , Proliferación Celular , Ensamble y Desensamble de Cromatina/genética , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Ratones , Neoplasias/irrigación sanguínea , Neoplasias/enzimología , Neovascularización Patológica/genética , Regiones Promotoras Genéticas/genética , Unión Proteica , Proteínas Serina-Treonina Quinasas/deficiencia , Proteínas Represoras/metabolismo , Factor A de Crecimiento Endotelial Vascular/genética
13.
J Mol Recognit ; 23(4): 343-51, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-19941302

RESUMEN

Azurin, a bacterial protein, can be internalized in cancer cells and induce apoptosis. Such anticancer effect is coupled to the formation of a complex with the tumour-suppressor p53. The mechanism by which azurin stabilizes p53 and the binding sites of their complex are still under investigation. It is also known that the predominant mechanism for p53 down-regulation implies its association to Mdm2, the main ubiquitin ligase affecting its stability. However, the p53/Mdm2 interaction, occurring at the level of both their N-terminal domains, has been characterized so far by experiments involving only partial domains of these proteins. The relevance of the p53/Mdm2 complex as a possible target of the anticancer therapies requires a deeper study of this complex as made up of the two entire proteins. Moreover, the apparent antagonist action of azurin against Mdm2, with respect of p53 regulation, might suggest the possibility that azurin binds p53 at the same site of Mdm2, preventing in such a way p53 and Mdm2 from association and thus p53 from degradation. By following the interaction of the two entire proteins by atomic force spectroscopy, we have assessed the formation of a specific complex between p53 and Mdm2. We found for it a binding strength and a dissociation rate constant typical of dynamical protein-protein interactions and we observed that azurin, even if capable to bind p53, does not compete with Mdm2 for the same binding site on p53. The formation of the p53/Mdm2/azurin ternary complex might suggest an alternative anti-cancer mechanism adopted by azurin.


Asunto(s)
Azurina/metabolismo , Microscopía de Fuerza Atómica , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Azurina/genética , Humanos , Modelos Biológicos , Unión Proteica , Proteínas Proto-Oncogénicas c-mdm2/genética , Proteína p53 Supresora de Tumor/genética
14.
Exp Cell Res ; 315(1): 67-75, 2009 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-18996371

RESUMEN

The maintenance of p53 transactivation activity is important for p53 apoptotic function. We have shown that stable knockdown of HIPK2 induces p53 misfolding with inhibition of p53 target gene transcription. In this study we established a lentiviral-based system for doxycyclin (Dox)-induced conditional interference of HIPK2 expression to evaluate the molecular mechanisms involved in p53 deregulation. We found that HIPK2 knockdown induced metallothionein 2A (MT2A) upregulation as assessed by RT-PCR analysis, increased promoter acetylation, and increased promoter luciferase activity. The MT2A upregulation correlated with resistance to Adriamycin (ADR)-driven apoptosis and with p53 inhibition. Thus, acute knockdown of HIPK2 (HIPK2i) induced misfolded p53 protein in MCF7 breast cancer cells and inhibited p53 DNA-binding and transcription activities in response to ADR treatment. Previous works show that MT may modulate p53 activity through zinc exchange. Here, we found that inhibition of MT2A expression by siRNA in the HIPK2i cells restored p53 transcription activity. Similarly zinc supplementation to HIPK2i cells restored p53 transcription activity and drug-induced apoptosis. These data support the notion that MT2A is involved in p53 deregulation and strengthen the possibility that combination of chemotherapy and zinc might be useful to treat tumors with inactive wtp53.


Asunto(s)
Metalotioneína/metabolismo , Proteínas Serina-Treonina Quinasas/deficiencia , Proteína p53 Supresora de Tumor/metabolismo , Zinc/metabolismo , Apoptosis/efectos de los fármacos , Proteínas Portadoras/metabolismo , Línea Celular Tumoral , ADN de Neoplasias/metabolismo , Doxorrubicina/farmacología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Lentivirus , Fosforilación/efectos de los fármacos , Fosfoserina/metabolismo , Unión Proteica/efectos de los fármacos , Conformación Proteica/efectos de los fármacos , Pliegue de Proteína/efectos de los fármacos , Proteínas Serina-Treonina Quinasas/metabolismo , Transcripción Genética/efectos de los fármacos , Activación Transcripcional/efectos de los fármacos , Proteína p53 Supresora de Tumor/química , Proteína p53 Supresora de Tumor/genética , Regulación hacia Arriba/efectos de los fármacos , Zinc/farmacología
15.
Mol Cancer ; 8: 1, 2009 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-19128456

RESUMEN

BACKGROUND: Homeodomain-interacting protein kinase-2 (HIPK2), a transcriptional co-repressor with apoptotic function, can affect hypoxia-inducible factor 1 (HIF-1) transcriptional activity, through downmodulation of its HIF-1alpha subunit, in normoxic condition. Under hypoxia, a condition often found in solid tumors, HIF-1alpha is activated to induce target genes involved in chemoresistance, inhibition of apoptosis and tumor progression. Here, we investigated whether the HIPK2 overexpression could downregulate HIF-1alpha expression and activity in tumor cells treated with hypoxia-mimicking condition, and evaluated whether HIPK2-dependent downregulation of HIF-1alpha could sensitize chemoresistant tumor cells to adriamycin (ADR)-induced apoptosis. METHODS: Tumor cell lines carrying wild-type p53, siRNA p53, or mutant p53 were overexpressed with HIPK2 (full length or catalytic inactive mutant) and treated with cobalt chloride (CoCl2) to mimic hypoxia, in the presence or absence of ADR treatment. HIF-1alpha expression was measured by semiquantitative reverse-transcriptase (RT)-PCR and Western immunoblotting and HIF-1 activity was evaluated by luciferase assay using reporter plasmid containing hypoxia response elements (HREs) upstream of luciferase gene. HIF-1 target genes, including multidrug resistance 1 (MDR1) and the antiapoptotic Bcl2 were determined by RT-PCR. Cell survival and apoptosis were measured by colony assay and cleavage of the caspase-3 substrate PARP, respectively. RESULTS: Overexpression of HIPK2 resulted in downmodulation of cobalt-stabilized HIF-1alpha protein and HIF-1alpha mRNA levels, with subsequent inhibition of HIF-1 transcriptional activity. MDR1 and Bcl-2 gene expression was downmodulated by HIPK2 overexpression in cobalt-treated cells. Inhibition of HIF-1 transcriptional activity was dependent on HIPK2 catalytic activity. HIPK2 overexpression did not induce per se apoptosis of cobalt-treated cells, on the contrary it sensitized cobalt-treated cells to ADR-induced apoptosis, regardless of their p53 status. CONCLUSION: The ability of HIPK2 to restore the apoptosis-inducing potential of chemotherapeutic drug in hypoxia-mimicking condition and therefore to sensitize chemoresistant tumor cells suggests that HIPK2 may induce fundamental alterations in cell signaling pathways, involving or not p53 function. Thus potential use of HIPK2 is promising for cancer treatment by potentiating cytotoxic therapies, regardless of p53 cell status.


Asunto(s)
Apoptosis/fisiología , Proteínas Portadoras/metabolismo , Resistencia a Antineoplásicos/fisiología , Regulación Neoplásica de la Expresión Génica/fisiología , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Antibióticos Antineoplásicos/farmacología , Western Blotting , Hipoxia de la Célula/efectos de los fármacos , Hipoxia de la Célula/fisiología , Línea Celular Tumoral , Doxorrubicina/farmacología , Humanos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transfección , Proteína p53 Supresora de Tumor/metabolismo
16.
Mol Cancer ; 8: 85, 2009 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-19828042

RESUMEN

BACKGROUND: Activation of p53-mediated gene transcription is a critical cellular response to DNA damage and involves a phosphorylation-acetylation cascade of p53. The discovery of differences in the response to different agents raises the question whether some of the p53 oncosuppressor functions might be exerted by different posttranslational modifications. Stress-induced homeodomain-interacting protein kinase-2 (HIPK2) phosphorylates p53 at serine-46 (Ser46) for p53 apoptotic activity; p53 acetylation at different C-terminus lysines including p300-mediated lysine-382 (Lys382) is also required for full activation of p53 transcriptional activity. The purpose of the current study was to evaluate the interplay among HIPK2, p300, and p53 in p53 acetylation and apoptotic transcriptional activity in response to drug by using siRNA interference, p300 overexpression or deacetylase inhibitors, in cancer cells. RESULTS: Knockdown of HIPK2 inhibited both adriamycin-induced Ser46 phosphorylation and Lys382 acetylation in p53 protein; however, while combination of ADR and zinc restored Ser46 phosphorylation it did not recover Lys382 acetylation. Chromatin immunoprecipitation studies showed that HIPK2 was required in vivo for efficient p300/p53 co-recruitment onto apoptotic promoters and that both p53 modifications at Ser46 and Lys382 were necessary for p53 apoptotic transcription. Thus, p53Lys382 acetylation in HIPK2 knockdown as well as p53 apoptotic activity in response to drug could be rescued by p300 overexpression. Similar effect was obtained with the Sirt1-inhibitor nicotinamide. Interestingly trichostatin A (TSA), the inhibitor of histone deacetylase complexes (HDAC) did not have effect, suggesting that Sirt1 was the deacetylase involved in p53 deacetylation in HIPK2 knockdown. CONCLUSION: These results reveal a novel role for HIPK2 in activating p53 apoptotic transcription. Our results indicate that HIPK2 may regulate the balance between p53 acetylation and deacetylation, by stimulating on one hand co-recruitment of p300 and p53Lys382 on apoptotic promoters and on the other hand by inhibiting Sirt1 deacetylase activity. We attempted to reactivate p53 apoptotic transcriptional activity by rescuing both Ser46 and Lys382 modification in response to drug. Our data propose combination strategies for the treatment of tumors with dysfunctional p53 and/or HIPK2 that include classical chemotherapy with pharmacological or natural agents such as Sirt1-deacetylase inhibitors or zinc, respectively.


Asunto(s)
Apoptosis/genética , Proteínas Portadoras/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Transcripción Genética , Proteína p53 Supresora de Tumor/metabolismo , Acetilación/efectos de los fármacos , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Doxorrubicina/farmacología , Proteína p300 Asociada a E1A/metabolismo , Eliminación de Gen , Técnicas de Silenciamiento del Gen , Humanos , Ácidos Hidroxámicos/farmacología , Lisina/metabolismo , Niacinamida/farmacología , Fosforilación/efectos de los fármacos , Regiones Promotoras Genéticas/genética , Unión Proteica/efectos de los fármacos , Sirtuina 1/metabolismo , Transcripción Genética/efectos de los fármacos , Zinc/farmacología , Proteína X Asociada a bcl-2/metabolismo
17.
Gynecol Oncol ; 109(3): 403-10, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18395248

RESUMEN

OBJECTIVE: Chemoresistance, due to inhibition of apoptotic response, is the major reason for the failure of anticancer therapies. HIPK2 regulates p53-apoptotic function via serine-46 (Ser46) phosphorylation and activation of p53 is a key determinant in ovarian cancer cell death. In this study we determined whether HIPK2 overexpression restored apoptotic response in chemoresistant cancer cells. METHODS: Using cisplatin chemosensitive (2008) and chemoresistant (2008C13) ovarian cancer cell lines we compared drug-induced activation of the HIPK2/p53Ser46 apoptotic pathway. The levels of HIPK2, Ser46 phosphorylation, and PARP cleavage were detected by Western blotting. The p53Ser46 apoptotic commitment was evaluated by luciferase assay using the Ser46 specific AIP1 target gene promoter. The apoptotic pathway was detected by caspase-3, -8, and -9 activities. RESULTS: HIPK2 was expressed differently in sensitive versus chemoresistant cells in response to different chemotherapeutic drugs (i.e., cisplatin and adriamycin), though the p53Ser46 apoptotic pathway was not defective in chemoresistant 2008C13 cells. Thus, 2008C13 cells were resistant to cisplatin but sensitive to adriamycin-induced apoptosis through activation of the HIPK2/p53Ser46 pathway. HIPK2 knock-down inhibited the adriamycin-induced apoptosis in 2008C13 cells. Exogenous HIPK2 triggered apoptosis in chemoresistant cells, associated with induction of p53Ser46-target gene AIP1. CONCLUSIONS: HIPK2 is an important regulator of p53 activity in response to a chemotherapeutic drug. These results suggest that different drug-activated pathways may regulate HIPK2 and that HIPK2/p53Ser46 deregulation is involved in chemoresistance. Exogenous HIPK2 might represent a novel therapeutic approach to circumvent inhibition of apoptosis in treatment of chemoresistant ovarian cancers with wtp53.


Asunto(s)
Apoptosis/efectos de los fármacos , Apoptosis/fisiología , Proteínas Portadoras/biosíntesis , Cisplatino/farmacología , Doxorrubicina/farmacología , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/metabolismo , Proteínas Serina-Treonina Quinasas/biosíntesis , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Caspasas/metabolismo , Línea Celular Tumoral , Cistadenocarcinoma Seroso/tratamiento farmacológico , Cistadenocarcinoma Seroso/metabolismo , Cistadenocarcinoma Seroso/patología , Resistencia a Antineoplásicos , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Neoplasias Ováricas/genética , Neoplasias Ováricas/patología , Fosforilación , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo
18.
Skinmed ; 6(1): 41-4, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17215622

RESUMEN

An 82-year-old man with hypothyroidism presented with an ulcerated nodule on the dorsum of his left hand (Figure 1). The lesion had been present for about 3 months. Similar lesions were present along the lymphatic distribution of the dorsum of his left forearm, proximal to the first lesion, as well as the dorsum of his right forearm. Laboratory findings were normal. Immune complexes, complement 3, and complement 4 were negative. A biopsy from an ulcerated nodule was taken for both histologic examination and culture. Hematoxylin and eosin sections showed a nonspecific chronic granulomatous reaction. No fungi were detected by periodic acid-Schiff stain and methenamine silver stain. Culture of tissue obtained from a skin biopsy of 1 lesion placed directly on Sabouraud agar produced colonies of Sporothrix schenckii (Figure 2). The diagnosis of lymphocutaneous sporotrichosis was confirmed.


Asunto(s)
Antifúngicos/uso terapéutico , Dermatosis de la Mano/tratamiento farmacológico , Itraconazol/uso terapéutico , Esporotricosis/tratamiento farmacológico , Anciano de 80 o más Años , Humanos , Masculino , Inducción de Remisión
20.
Redox Biol ; 11: 111-117, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-27912195

RESUMEN

Cholesterol is a main lipid component of sperm cell that is essential for sperm membrane fluidity, capacitation, and acrosomal reaction. Recent data obtained in bovine sperm showed that sperm capacitation is associated to the formation of oxysterols, oxidized products of cholesterol. The aim of this study was to profile oxysterol content in human semen, and to investigate their potential role in sperm pathophysiology. Among the 12 oxysterols analyzed, 25-hydroxycholesterol (25-HC) resulted the most represented in normozoospermic samples, and its concentration positively correlated with spermatozoa number. We detected Cholesterol 25-hydroxylase, the enzyme responsible for 25-HC production, in human spermatozoa at the level of the neck and the post acrosomal area. Upon incubation with spermatozoa, 25-HC induced calcium and cholesterol transients in connection with the acrosomal reaction. Our results support a role for 25-HC in sperm function.


Asunto(s)
Hidroxicolesteroles/metabolismo , Capacitación Espermática/fisiología , Espermatozoides/metabolismo , Esteroide Hidroxilasas/metabolismo , Acrosoma/metabolismo , Calcio/metabolismo , Colesterol/metabolismo , Humanos , Masculino , Fluidez de la Membrana/genética , Capacitación Espermática/genética , Motilidad Espermática/genética , Esteroide Hidroxilasas/genética
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