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1.
Arch Gynecol Obstet ; 296(3): 429-433, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28664483

RESUMEN

PURPOSE: Dienogest has recently been marketed as a medical treatment for endometriosis. Given the recent introduction on the market of Dienogest, little data are available regarding its effectiveness in routine clinical practice. METHODS: The study is an observational, single-center, cohort study. Eligible was women with a surgical diagnosis of endometriosis dating back <24 months or a clinical/instrumental diagnosis of endometriosis and endometriosis-associated pelvic pain score of at least 40 mm on a 100-mm visual analog scale (VAS) at start of treatment and who had been taking Dienogest 2 mg once daily treatment at the time of study entry for no more than 30 days, consecutively observed between September 2013 to September 2014. In accordance with routine practice, women came back for clinical assessment and evaluation of pain after 1 (V1), 3 (V2), and 12 (V3) months. RESULTS: A total of 132 women were enrolled in the study. A total of 21 of the enrolled patients were released from the study during follow-up due to adverse effects. The mean pelvic pain VAS score at baseline was 8.9 (SD 1.3). The corresponding values were 6.7 (SD 3.2) and 5.7 (SD 3.7) for dyspareunia and dyschezia. The mean VAS scores progressively and significantly decreased to 0.9 (SD 1.6) for pelvic pain, 1.4 (SD 2.1) for dyspareunia and 0.2 (SD 0.9) for dyschezia, respectively, 12 months after start of treatment. CONCLUSION: This study confirms that in routine clinical practice, Dienogest 2 mg is an effective and well-tolerated treatment for endometriosis-related pain in women with endometriosis.


Asunto(s)
Endometriosis/tratamiento farmacológico , Antagonistas de Hormonas/uso terapéutico , Nandrolona/análogos & derivados , Dolor Pélvico/tratamiento farmacológico , Adolescente , Adulto , Estudios de Cohortes , Dispareunia/tratamiento farmacológico , Endometriosis/complicaciones , Femenino , Antagonistas de Hormonas/efectos adversos , Humanos , Persona de Mediana Edad , Nandrolona/efectos adversos , Nandrolona/uso terapéutico , Dimensión del Dolor , Resultado del Tratamiento
2.
Oncogene ; 35(9): 1111-21, 2016 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-25982283

RESUMEN

IMP3 (insulin-like growth factor-2 mRNA binding protein 3) is an oncofetal protein whose expression is prognostic for poor outcome in several cancers. Although IMP3 is expressed preferentially in triple-negative breast cancer (TNBC), its function is poorly understood. We observed that IMP3 expression is significantly higher in tumor initiating than in non-tumor initiating breast cancer cells and we demonstrate that IMP3 contributes to self-renewal and tumor initiation, properties associated with cancer stem cells (CSCs). The mechanism by which IMP3 contributes to this phenotype involves its ability to induce the stem cell factor SOX2. IMP3 does not interact with SOX2 mRNA significantly or regulate SOX2 expression directly. We discovered that IMP3 binds avidly to SNAI2 (SLUG) mRNA and regulates its expression by binding to the 5' UTR. This finding is significant because SLUG has been implicated in breast CSCs and TNBC. Moreover, we show that SOX2 is a transcriptional target of SLUG. These data establish a novel mechanism of breast tumor initiation involving IMP3 and they provide a rationale for its association with aggressive disease and poor outcome.


Asunto(s)
Biomarcadores de Tumor/biosíntesis , Proteínas de Unión al ARN/biosíntesis , Factores de Transcripción/biosíntesis , Neoplasias de la Mama Triple Negativas/genética , Biomarcadores de Tumor/genética , Regulación Neoplásica de la Expresión Génica , Humanos , Células Madre Neoplásicas , Pronóstico , ARN Mensajero/biosíntesis , Proteínas de Unión al ARN/genética , Factores de Transcripción SOXB1/genética , Factores de Transcripción de la Familia Snail , Factores de Transcripción/genética , Neoplasias de la Mama Triple Negativas/patología
3.
Integr Biol (Camb) ; 7(2): 198-212, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25537447

RESUMEN

Breast cancer preferentially spreads to the bone, brain, liver, and lung. The clinical patterns of this tissue-specific spread (tropism) cannot be explained by blood flow alone, yet our understanding of what mediates tropism to these physically and chemically diverse tissues is limited. While the microenvironment has been recognized as a critical factor in governing metastatic colonization, the role of the extracellular matrix (ECM) in mediating tropism has not been thoroughly explored. We created a simple biomaterial platform with systematic control over the ECM protein density and composition to determine if integrin binding governs how metastatic cells differentiate between secondary tissue sites. Instead of examining individual behaviors, we compiled large patterns of phenotypes associated with adhesion to and migration on these controlled ECMs. In combining this novel analysis with a simple biomaterial platform, we created an in vitro fingerprint that is predictive of in vivo metastasis. This rapid biomaterial screen also provided information on how ß1, α2, and α6 integrins might mediate metastasis in patients, providing insights beyond a purely genetic analysis. We propose that this approach of screening many cell-ECM interactions, across many different heterogeneous cell lines, is predictive of in vivo behavior, and is much simpler, faster, and more economical than complex 3D environments or mouse models. We also propose that when specifically applied toward the question of tissue tropism in breast cancer, it can be used to provide insight into certain integrin subunits as therapeutic targets.


Asunto(s)
Neoplasias de la Mama/patología , Neoplasias de la Mama/fisiopatología , Matriz Extracelular/patología , Matriz Extracelular/fisiología , Metástasis de la Neoplasia/patología , Metástasis de la Neoplasia/fisiopatología , Animales , Materiales Biocompatibles , Adhesión Celular , Línea Celular Tumoral , Movimiento Celular , Femenino , Ensayos Analíticos de Alto Rendimiento/métodos , Humanos , Integrinas/fisiología , Células MCF-7 , Ratones , Especificidad de Órganos , Fenotipo , Biología de Sistemas , Microambiente Tumoral/fisiología
4.
Case Rep Med ; 2013: 747431, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23424596

RESUMEN

Sjögren syndrome (SS) is an autoimmune disease of the exocrine glands, characterized by focal lymphocytic infiltration and destruction of these glands. Neurologic complications are quite common, mainly involving the peripheral nervous system (PNS). The most common central nervous system (CNS) manifestations are myelopathy and microcirculation vasculitis. However, specific diagnostic criteria for CNS SS are still lacking. We report two cases of primary SS in which the revealing symptom was cerebral venous thrombosis (CVT) in the absence of genetic or acquired thrombophilias.

5.
Oncogene ; 31(44): 4689-97, 2012 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-22266872

RESUMEN

Insulin-like growth factor II (IGF-II) mRNA-binding protein 3 (IMP3) is emerging as a useful indicator of the progression and outcome of several cancers. IMP3 expression is associated with triple-negative breast carcinomas (TNBCs), which are aggressive tumors associated with poor outcome. In this study, we addressed the hypothesis that signaling pathways, which are characteristic of TNBCs, impact the expression of IMP3 and that IMP3 contributes to the function of TNBCs. The data obtained reveal that IMP3 expression is repressed specifically by estrogen receptor ß (ERß) and its ligand 3ßA-diol but not by ERα. Epidermal growth factor receptor (EGFR) signaling and consequent activation of the mitogen-activated protein kinase pathway induce IMP3 transcription and expression. Interestingly, we discovered that the EGFR promoter contains an imperfect estrogen response element and that ERß represses EGFR transcription. These data support a mechanism in which ERß inhibits IMP3 expression indirectly by repressing the EGFR. This mechanism relates to the biology of TNBC, which is characterized by diminished ERß and increased EGFR expression. We also demonstrate that IMP3 contributes to the migration and invasion of breast carcinoma cells. Given that IMP3 is an mRNA-binding protein, we determined that it binds several key mRNAs that could contribute to migration and invasion, including CD164 (endolyn) and MMP9. Moreover, expression of these mRNAs is repressed by ERß and enhanced by EGFR signaling, consistent with our proposed mechanism for the regulation of IMP3 expression in breast cancer cells. Our findings show that IMP3 is an effector of EGFR-mediated migration and invasion and they provide the first indication of how this important mRNA-binding protein is regulated in cancer.


Asunto(s)
Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Receptores ErbB/metabolismo , Receptor beta de Estrógeno/metabolismo , Regulación Neoplásica de la Expresión Génica , Proteínas de Unión al ARN/genética , Transducción de Señal , Línea Celular Tumoral , Movimiento Celular/genética , Receptores ErbB/genética , Femenino , Humanos , Proteínas de Unión al ARN/metabolismo , Receptor ErbB-2/metabolismo , Receptores de Estrógenos/metabolismo , Receptores de Progesterona/metabolismo
6.
Eur J Neurol ; 19(3): 517-21, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22175796

RESUMEN

BACKGROUND AND PURPOSE: Post-stroke depression (PSD) is one of the most frequent complications of stroke, with a prevalence ranging 20-60%. As PSD seems to be related to stroke severity, we hypothesized that the prevalence of PSD would be lower in patients with minor stroke. METHODS: We investigated the prevalence and predictors of PSD over a 30-month follow-up period in a cohort of patients with minor ischaemic stroke (NIHSS≤5). RESULTS: We enrolled 105 patients (mean age 64.38±11.2years, M/F 69/36). PSD was diagnosed in 43 (41%) patients, 40 (93%) of whom had dysthymia; 22% of patients were already depressed at 1month. The most frequent depressive symptoms (DSs) were working inhibition, indecisiveness, and fatigability. Patients who developed PSD were less educated (P=0.044) and diabetic (P=0.006). After excluding patients that were already depressed at 1month, we performed a logistic regression model to detect predictors of PSD. Crying (P=0.012, OR 1.067, CI 0.269-4.553) and guilt (P=0.007, OR 0.037, CI 0.02ì03-0.401) at baseline were two DSs found to be significantly correlated with PSD. Higher educational level (P=0.022, OR 0.084, CI 0.010-0.698) and diabetes (P=0.007, OR 14.361, CI 2.040-101.108) were the risk factors significantly correlated with PSD. CONCLUSION: Post-stroke depression is frequent even in patients with minor stroke. Early detection of DSs might help to predict long-term development of PSD. No correlation was observed between lesion site or side and the development of PSD.


Asunto(s)
Depresión/epidemiología , Depresión/etiología , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/psicología , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Factores de Riesgo , Accidente Cerebrovascular/patología
7.
Cephalalgia ; 29(3): 293-9, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19220310

RESUMEN

We studied the effects of short-term psychodynamic psychotherapy (STPP) and pharmacological therapy in 26 consecutive patients with probable medication overuse headache (pMOH). Patients underwent a standard in-patient detoxification protocol, lasting a mean of 7 days. Eleven patients overused non-steroidal anti-inflammatory drugs (NSAIDs), five a combination of NSAIDs and triptans, four triptans, four a combination of NSAIDs, and three triptans and ergot derivates. Preventive therapy was initiated during detoxification. The STPP protocol comprised the Brief Psychodynamic Investigation (BPI) and psychoanalysis-inspired psychotherapy. All patients (groups A and B) underwent the BPI and pharmacological therapy. Half of the patients (group B) also not randomly underwent psychoanalysis-inspired psychotherapy. We found a significant interaction between time and group for headache frequency and medication intake. At 12-month follow-up, a statistically greater decrease in headache frequency and medication intake was observed in group B than in group A (P = 0.0108 and P = 0.0097, respectively). The relapse rate was much lower in group B patients at both 6 and 12 months [15.3%, odds ratio (OR) 0.11, P = 0.016, and 23%, OR 0.18, P = 0.047, respectively] than in group A. The risk of developing chronic migraine (CM) during follow-up was higher in group A than in group B at 6 (OR 2.0, P = 0.047) and 12 months (OR 2.75, P = 0.005). Our study suggests that STPP in conjunction with drug withdrawal and prophylactic pharmacotherapy relieves headache symptoms in pMOH, reducing both long-term relapses and the burden of CM.


Asunto(s)
Analgésicos no Narcóticos/uso terapéutico , Cefaleas Secundarias/terapia , Psicoterapia Breve/métodos , Adulto , Anciano , Terapia Combinada , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Proyectos Piloto
8.
Oncogene ; 25(52): 6959-67, 2006 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-16715134

RESUMEN

Understanding how RhoC expression and activation are regulated is essential for deciphering its contribution to tumorigenesis. Here, we report that RhoC expression and activation are induced by the epithelial to mesenchymal transition (EMT) of colon carcinoma. Using LIM 1863 colon cancer cells, RhoC protein expression and subsequent activation were detected coincident with the loss of E-cadherin and acquisition of mesenchymal characteristics. Several Ets-1 binding sites were identified in the RhoC promoter, and evidence was obtained using chromatin immunoprecipitation that Ets-1 can regulate RhoC expression during the EMT. Interestingly, a marked decrease in RhoA activation associated with the EMT was observed that corresponds to the increase in RhoC expression. Use of shRNA established that RhoA inhibits and RhoC promotes post-EMT cell migration, demonstrating functional significance for their coordinate regulation. To assess the importance of RhoC expression in colon cancer, immunohistochemistry was performed on 566 colorectal tumors with known clinical outcome. The level of RhoC ranged from no expression to high expression, and statistical analysis revealed that elevated RhoC expression correlates with poor outcome as well as aberrant expression and localization of E-cadherin. These data provide one mechanism for how RhoC expression is regulated in colon carcinoma and substantiate its utility as a prognostic marker.


Asunto(s)
Biomarcadores de Tumor/análisis , Neoplasias del Colon/enzimología , Invasividad Neoplásica/genética , Proteínas de Unión al GTP rho/metabolismo , Proteína de Unión al GTP rhoA/metabolismo , Cadherinas/metabolismo , Línea Celular Tumoral , Neoplasias del Colon/patología , Activación Enzimática/fisiología , Células Epiteliales/enzimología , Humanos , Inmunohistoquímica , Inmunoprecipitación , Pronóstico , Regiones Promotoras Genéticas , Proteína Proto-Oncogénica c-ets-1/metabolismo , ARN Interferente Pequeño , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transcripción Genética , Proteínas de Unión al GTP rho/genética , Proteína rhoC de Unión a GTP
9.
J Craniofac Surg ; 16(2): 332-4, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15750437

RESUMEN

We have studied a common aspect of both adenoid cystic carcinoma (ACC) and neuroblastoma (NB) with the purpose of finding the optimal medical and surgical treatment. This article is based on a case study involving 22 cases of ACC and NB performed at the University of Rome La Sapienza from 1993 to 2001. Of the 22 cases, 17 were diagnosed with ACC and 5 with NB. ACC largely involved the maxillae, having been detected in this location in eight cases. Two of these patients, one affected by ACC and the other affected by NB, received neoadjuvant treatment, whereas 14 were affected by ACC, and 3 with NB received adjuvant treatment. Despite the fact that the two neoplasms have different embryogenic structures, they share common aspects. Both spread invasively through the perineural sheets, and both are responsive to radiotherapy or chemotherapy. The common biologic behavior and the similar response that both show to neoadjuvant radiotherapy or chemotherapy may suggest a way to develop a more effective treatment protocol. The aim of this article is to suggest a line of research along that path.


Asunto(s)
Carcinoma Adenoide Quístico/patología , Neoplasias de Cabeza y Cuello/patología , Terapia Neoadyuvante , Neuroblastoma/patología , Adulto , Anciano , Carcinoma Adenoide Quístico/cirugía , Quimioterapia Adyuvante , Femenino , Estudios de Seguimiento , Neoplasias de Cabeza y Cuello/cirugía , Humanos , Neoplasias Maxilomandibulares/patología , Neoplasias Maxilomandibulares/cirugía , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , Neuroblastoma/cirugía , Radioterapia Adyuvante , Resultado del Tratamiento
10.
Mol Biol Cell ; 12(12): 4030-43, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11739798

RESUMEN

The integrin alpha6beta4, a laminin receptor that stabilizes epithelial cell adhesion to the basement membrane (BM) through its association with cytokeratins, can stimulate the formation and stabilization of actin-rich protrusions in carcinoma cells. An important, unresolved issue, however, is whether this integrin can transmit forces to the substrate generated by the acto-myosin system. Using a traction-force detection assay, we detected forces exerted through alpha6beta4 on either laminin-1 or on an anti-alpha6 antibody, demonstrating that this integrin can transmit forces without the need to engage other integrins. These alpha6beta4-dependent traction forces were organized into a compression machine localized to the base of lamellae. We hypothesized that the compression forces generated by alpha6beta4 result in the remodeling of BMs because this integrin plays a major role in the interaction of epithelial and carcinoma cells with such structures. Indeed, we observed that carcinoma cells are able to remodel a reconstituted BM through alpha6beta4-mediated compression forces by a process that involves the packing of BM material under the cells and the mechanical removal of BM from adjacent areas. The distinct signaling functions of alpha6beta4, which activate phosphoinositide 3-OH kinase and RhoA, also contribute to remodeling. Importantly, we demonstrate remodeling of a native BM by epithelial cells and the involvement of alpha6beta4 in this remodeling. Our findings have important implications for the mechanism of both BM organization and tumor invasion.


Asunto(s)
Antígenos de Superficie/metabolismo , Membrana Basal/citología , Membrana Basal/metabolismo , Integrinas/metabolismo , Invasividad Neoplásica , Neoplasias/metabolismo , Neoplasias/patología , Membrana Basal/ultraestructura , Neoplasias de la Mama/metabolismo , Adhesión Celular , Matriz Extracelular/metabolismo , Humanos , Integrina alfa6beta4 , Laminina/metabolismo , Microscopía Electrónica , Microscopía Fluorescente , Microscopía por Video , Seudópodos/metabolismo , Transducción de Señal , Células Tumorales Cultivadas
11.
J Biol Chem ; 276(51): 47895-900, 2001 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-11606581

RESUMEN

Members of the Rho family of small GTPases, such as Rho and Rac, are required for actin cytoskeletal reorganization during the migration of carcinoma cells. Phosphodiesterases are necessary for this migration because they alleviate cAMP-dependent protein kinase (PKA)-mediated inhibition of RhoA (O'Connor, K. L., Shaw, L. M., and Mercurio, A. M. (1998) J. Cell Biol. 143, 1749-1760; O'Connor K. L., Nguyen, B.-K., and Mercurio, A. M. (2000), J. Cell Biol. 148, 253-258). In this study, we report that the migration of breast and squamous carcinoma cells toward either lysophosphatidic acid or epidermal growth factor involves not only phosphodiesterase activity but also cooperative signaling from PKA. Furthermore, we demonstrate that Rac1 activation in response to chemoattractant or beta(1) integrin clustering is regulated by PKA and that Rac1 is required for this migration. Also, we find that beta(1) integrin signaling stimulates the rapid and transient activation of PKA. A novel implication of these findings is that carcinoma cell migration is controlled by cAMP-dependent as well as cAMP inhibitory signaling mechanisms.


Asunto(s)
Neoplasias de la Mama/patología , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Proteínas de Unión al GTP rac/metabolismo , Neoplasias de la Mama/enzimología , Neoplasias de la Mama/metabolismo , Quimiotaxis/efectos de los fármacos , Factor de Crecimiento Epidérmico/farmacología , Humanos , Integrina beta1/metabolismo , Lisofosfolípidos/farmacología , Transducción de Señal , Células Tumorales Cultivadas , Proteína de Unión al GTP rhoA/metabolismo
12.
J Mammary Gland Biol Neoplasia ; 6(3): 299-309, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11547899

RESUMEN

This review explores the mechanistic basis of breast carcinoma progression by focusing on the contribution of integrins. Integrins are essential for progression not only for their ability to mediate physical interactions with extracellular matrices but also for their ability to regulate signaling pathways that control actin dynamics and cell movement, as well as for growth and survival. Our comments center on the alpha6 integrins (alpha6beta1 and alpha6beta4), which are receptors for the laminin family of basement membrane components. Numerous studies have implicated these integrins in breast cancer progression and have provided a rationale for studying the mechanistic basis of their contribution to aggressive disease. Recent work by our group and others on mechanisms of breast carcinoma invasion and survival that are influenced by the alpha6 integrins are discussed.


Asunto(s)
Antígenos de Neoplasias/metabolismo , Antígenos de Superficie/metabolismo , Antígenos de Superficie/fisiología , Neoplasias de la Mama/metabolismo , Integrinas/fisiología , Neoplasias de la Mama/mortalidad , Movimiento Celular/fisiología , Progresión de la Enfermedad , Femenino , Humanos , Integrina alfa6beta4 , Fosfatidilinositol 3-Quinasas/metabolismo , Tasa de Supervivencia
13.
Curr Opin Cell Biol ; 13(5): 541-5, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11544021

RESUMEN

Although the involvement of alpha 6 beta 4, an integrin laminin receptor, in hemidesmosome organization has dominated the study of this integrin, recent studies are revealing novel functions for alpha 6 beta 4 in the migration of epithelial and carcinoma cells. The engagement of laminin by alpha 6 beta 4 can stabilize actin-rich protrusions and mediate traction forces necessary for cell movement. This integrin also has a significant impact on signaling molecules that stimulate migration and invasion, especially PI3-K and Rho GTPases. Activation of PI3-K by alpha 6 beta 4 enhances the formation of actin protrusions, and it may stimulate the function of other integrins, such as alpha 3 beta 1, that are also important for epithelial migration. Signaling through alpha 6 beta 4 may not always depend on the adhesive functions of this integrin, a possibility that has profound implications for migration and invasion because it implies that the ability of alpha 6 beta 4 to stimulate these processes is not limited to specific matrix environments.


Asunto(s)
Antígenos de Superficie/fisiología , Movimiento Celular , Células Epiteliales/fisiología , Integrinas/fisiología , Animales , Antígenos de Superficie/química , Carcinoma/patología , Adhesión Celular , Hemidesmosomas/metabolismo , Integrina alfa6beta4 , Integrinas/química , Modelos Biológicos , Invasividad Neoplásica , Estructura Terciaria de Proteína , Transducción de Señal
14.
Oncol Nurs Forum ; 28(7): 1139-47, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11517847

RESUMEN

PURPOSE/OBJECTIVES: To provide an overview of cancer-related patient-education research to determine future research needs. DATA SOURCES: A literature search of peer-reviewed articles from 1989-1999. Databases that were searched included Medline, CINAHL, HealthStar, ERIC, CancerLit, and PubMed. DATA SYNTHESIS: 176 articles were analyzed and synthesized into narrative form. CONCLUSIONS: Patients with cancer want and benefit from information, especially when making treatment decisions. Education helps patients manage side effects and improves adherence. Literacy is an important factor in materials development. The efficacy of computer-assisted learning, audio and video programs, and telephone interventions is supported in a variety of patient groups. Pain education can improve pain control, but the impact on fatigue has not been well researched. IMPLICATIONS FOR NURSING PRACTICE: Patient education is an important component of nursing care. Research has confirmed its impact in many areas but questions still remain.


Asunto(s)
Neoplasias/enfermería , Investigación en Enfermería , Educación del Paciente como Asunto/métodos , Medios de Comunicación , Instrucción por Computador , Toma de Decisiones , Escolaridad , Humanos , Neoplasias/complicaciones , Materiales de Enseñanza
15.
J Biol Chem ; 276(39): 36535-42, 2001 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-11479315

RESUMEN

We used published peptide library data to identify PDZ recognition sequences in integrin alpha subunit cytoplasmic domains and found that the alpha(6)A and alpha(5) subunits contain a type I PDZ binding site (TSDA*) (asterisk indicates the stop codon). The alpha(6)A cytoplasmic domain was used for screening a two-hybrid library to find interacting proteins. The bulk of the captured cDNAs (60%) coded for TIP-2/GIPC, a cytoplasmic protein with one PDZ domain. The interaction of TIP-2/GIPC with different integrin subunits was tested in two-hybrid and in vitro binding assays. Surprisingly, TIP-2/GIPC bound strongly to the C terminus of both alpha(6)A and alpha(6)B, although the alpha(6)B sequence (ESYS*) is not suggestive of a PDZ binding site because of its polar C-terminal residue. For high affinity interaction with TIP-2/GIPC, at least one of the residues at positions -1 and -3 must be negatively charged. An aliphatic residue at position 0 increases the affinity of but is not required for this interaction. The alpha(5) integrin subunit also bound to TIP-2/GIPC. The alpha(6) integrin and TIP-2/GIPC co-localize in retraction fibers in carcinoma cells plated on laminin, a finding suggesting a functional interaction in vivo. Our results demonstrate that both splice variants of alpha(6) integrin contain a conserved PDZ binding site that enables interaction with TIP-2/GIPC. The binding site in alpha(6)B defines a new subclass of type I PDZ interaction site, characterized by a non-aliphatic residue at position 0.


Asunto(s)
Antígenos CD/química , Proteínas Portadoras/química , Proteínas Portadoras/metabolismo , Neuropéptidos/química , Neuropéptidos/metabolismo , Proteínas Adaptadoras Transductoras de Señales , Empalme Alternativo , Secuencia de Aminoácidos , Sitios de Unión , Northern Blotting , Adhesión Celular , Células Cultivadas , Glutatión Transferasa/metabolismo , Humanos , Integrina alfa5 , Integrina alfa6 , Datos de Secuencia Molecular , Biblioteca de Péptidos , Plásmidos/metabolismo , Mutación Puntual , Unión Proteica , Estructura Terciaria de Proteína , ARN Mensajero/metabolismo , Proteínas Recombinantes/metabolismo , Homología de Secuencia de Aminoácido , Células Tumorales Cultivadas , Técnicas del Sistema de Dos Híbridos
16.
Cancer Res ; 61(15): 5736-40, 2001 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-11479209

RESUMEN

We identify a novel function for the vascular endothelial growth factor (VEGF) in its ability to stimulate an autocrine signaling pathway in metastatic breast carcinoma cells that is essential for their survival. Suppression of VEGF expression in metastatic cells in vitro induced their apoptosis, in addition to inhibiting the constitutively elevated phosphatidylinositol 3'-kinase activity that is characteristic of these cells and important for their survival. Hypoxia enhanced the survival of metastatic cells by increasing VEGF expression. The importance of the VEGF receptor neuropilin was indicated by the ability of a neuropilin-binding VEGF isoform to enhance breast carcinoma survival. Moreover, the expression of neuropilin in neuropilin-deficient breast carcinoma cells protected them from apoptosis. The identification of this VEGF autocrine signaling pathway has important implications for tumor metastasis and therapeutic intervention.


Asunto(s)
Neoplasias de la Mama/patología , Factores de Crecimiento Endotelial/fisiología , Linfocinas/fisiología , Proteínas del Tejido Nervioso/fisiología , Apoptosis/efectos de los fármacos , Apoptosis/fisiología , Neoplasias de la Mama/metabolismo , Hipoxia de la Célula/fisiología , Supervivencia Celular/fisiología , Cromonas/farmacología , Factores de Crecimiento Endotelial/biosíntesis , Factores de Crecimiento Endotelial/genética , Activación Enzimática , Inhibidores Enzimáticos/farmacología , Humanos , Linfocinas/biosíntesis , Linfocinas/genética , Morfolinas/farmacología , Proteínas del Tejido Nervioso/biosíntesis , Neuropilina-1 , Fosfatidilinositol 3-Quinasas/metabolismo , Inhibidores de las Quinasa Fosfoinosítidos-3 , Transducción de Señal/fisiología , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial Vascular
17.
J Biol Chem ; 276(37): 34702-7, 2001 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-11463786

RESUMEN

Epithelial cells undergo death receptor-dependent apoptosis when detached from matrix, a process termed anoikis. Activation of Akt/protein kinase B (PKB) by matrix attachment protects cells from anoikis. In this study, we establish a link between anoikis and Akt/PKB-mediated survival by demonstrating that Akt/PKB is cleaved by caspases in matrix-detached epithelial cells by a mechanism that involves death receptors. Reduced levels of Akt/PKB protein were observed in detached Madin-Darby canine kidney cells relative to cells attached to collagen. Equivalent levels of Akt/PKB, however, were detected in matrix-adherent and detached cells after inhibition of caspase activity or expression of an Akt/PKB mutant (D108+119A) that is resistant to caspase cleavage. The contribution of death domain-containing proteins to Akt/PKB cleavage was evidenced by the ability of dominant negative Fas-associated death domain to restore normal levels of Akt/PKB in matrix-detached cells. Importantly, expression of a cleavage-resistant Akt/PKB mutant protected matrix-detached cells from apoptosis. These studies suggest that members of the death receptor family promote the caspase-mediated cleavage of Akt/PKB and that this event contributes to anoikis.


Asunto(s)
Apoptosis , Proteínas Serina-Treonina Quinasas , Proteínas Proto-Oncogénicas/metabolismo , Receptores del Factor de Necrosis Tumoral/fisiología , Animales , Anoicis , Caspasas/fisiología , Línea Celular , Perros , Proteínas Proto-Oncogénicas c-akt , Receptores del Ligando Inductor de Apoptosis Relacionado con TNF , Miembro 25 de Receptores de Factores de Necrosis Tumoral
18.
Surg Oncol Clin N Am ; 10(2): 313-28, viii-ix, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11382589

RESUMEN

This article explores the mechanistic basis of carcinoma progression by focusing on the contribution of integrins. Integrins are essential for progression because of their ability to mediate physical interactions with extracellular matrices and their ability to regulate signaling pathways that control actin dynamics and cell movement, and for growth and survival. This article centers on a6 integrins (a6B1 and a6B4), which are receptors for the laminin family of basement membrane components. Numerous studies have implicated these integrins in cancer progression and have provided a rationale for studying the mechanistic basis of their contribution to aggressive disease.


Asunto(s)
Integrinas/fisiología , Invasividad Neoplásica/genética , Invasividad Neoplásica/fisiopatología , Metástasis de la Neoplasia/genética , Metástasis de la Neoplasia/fisiopatología , Actinas/fisiología , Antígenos de Superficie/fisiología , Movimiento Celular/fisiología , Citoesqueleto/fisiología , Progresión de la Enfermedad , Humanos , Integrina alfa6beta1 , Integrina alfa6beta4 , Transducción de Señal/fisiología
19.
Semin Cancer Biol ; 11(2): 129-41, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11322832

RESUMEN

This review explores the mechanistic basis of carcinoma migration and invasion by focusing on the contribution of integrins. Integrins are essential for invasion not only for their ability to mediate physical interactions with extracellular matrices, but also for their ability to regulate signaling pathways that control actin dynamics and cell movement, as well as for growth and survival. Our comments center on a unique member of the integrin family, the alpha 6 beta 4 integrin, which is a receptor for the laminin family of basement membrane components. Numerous studies have implicated this integrin in the invasion of solid tumors and have provided a rationale for studying the mechanistic basis of its contribution to the invasive process. Such studies have revealed novel insights into the mechanism of carcinoma invasion that involve both the dynamics of cell migration and signaling pathways that regulate this migration.


Asunto(s)
Antígenos de Neoplasias/metabolismo , Antígenos de Superficie/metabolismo , Integrinas/metabolismo , Invasividad Neoplásica , Neoplasias/metabolismo , Movimiento Celular , AMP Cíclico/metabolismo , Humanos , Integrina alfa6beta4 , Fosfatidilinositol 3-Quinasas/metabolismo , Transducción de Señal
20.
J Biol Chem ; 275(14): 10604-10, 2000 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-10744756

RESUMEN

We previously demonstrated that beta(4) integrin subunit overexpression increases in vitro invasiveness of NIH3T3 cells that have been transformed by ErbB-2 oncogene. We used this model to identify domains within the large beta(4) cytoplasmic domain that are involved in the interaction of alpha(6)beta(4) with ErbB-2, invasion, and phosphatidylinositol 3-kinase (PI3K) activation. For this purpose, we expressed deletion mutants of beta(4) that lacked either all or portions of the beta(4) cytoplasmic domain in NIH3T3/ErbB-2 cells. We also used an ecto-domain mutant in which most of the extracellular domain of beta(4) was replaced with a c-Myc tag. These transfectants were examined for their ability to invade Matrigel and their ability to activate PI3K, as well as for the ability of alpha(6)beta(4) to co-immunoprecipitate with ErbB-2. The results obtained revealed that a region of the beta(4) cytoplasmic domain between amino acids 854 and 1183 is critical for the ability of alpha(6)beta(4) integrin to increase invasion. Interestingly, the extracellular domain of beta(4) is not necessary for alpha(6)beta(4) to stimulate invasion. The association of alpha(6)beta(4) with ErbB-2 is dependent upon the beta(4) cytoplasmic domain and can occur in the absence of alpha(6)beta(4) heterodimerization. Finally, we observed strong activation of PI3K with beta(4) wild type and with those beta(4) deletion mutants that were able to stimulate invasion upon the expression in NIH3T3/ErbB-2 cells. In conclusion, our results establish that there is cooperation between alpha(6)beta(4) and ErbB-2 in promoting PI3K-dependent invasion and implicate a specific region of the beta(4) cytoplasmic domain (amino acids 854-1183) in this event.


Asunto(s)
Antígenos de Superficie/fisiología , Integrinas/fisiología , Fosfatidilinositol 3-Quinasas/metabolismo , Receptor ErbB-2/fisiología , Transducción de Señal/fisiología , Células 3T3 , Animales , Antígenos de Superficie/química , Quimiotaxis , Colágeno , Dimerización , Combinación de Medicamentos , Activación Enzimática , Matriz Extracelular , Humanos , Integrina alfa6beta4 , Integrinas/química , Laminina , Ratones , Mutagénesis Sitio-Dirigida , Proteoglicanos , Proteínas Proto-Oncogénicas c-myc/genética , Receptor ErbB-2/genética , Proteínas Recombinantes/metabolismo , Eliminación de Secuencia , Transfección
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