RESUMEN
BACKGROUND: Sacral neuromodulation (SNM) is a widely used therapeutic option for fecal incontinence (FI). Larger series are mainly from Western countries, while few reports address the results of SNM in less developed or less wealthy countries. The aim of the present study was to evaluate the efficacy of SNM in patients with FI in Latin America. METHODS: A retrospective study was conducted on patients with FI who had SNM between 2009 and 2016 at 15 specialized colorectal surgery centers in Latin America. Main outcomes measures were functional outcomes, postoperative complications, requirement of revisional surgery, and requirement of device removal. All patients had failed conservative management and had clinical assessment including recording of the validated Cleveland Clinic Florida Fecal Incontinence Score (CCF-FIS) and, when available, anal manometry and endoanal ultrasound. Patients were followed up for a median of 36.7 (1-84) months. RESULTS: One hundred and thirty-one patients [119 females, median age of 62.2 (range 19-87) years] were included. The most common etiology of FI was obstetric injury (n = 60; 45.8%). After successful test lead implantation, the stimulator was permanently placed in 129 patients (98.5%). One patient failed to respond in the test phase and one patient did not proceed to permanent implantation for insurance reasons. Nineteen patients (14.7%) had 19 complications including infection (n = 5, 3.8%), persistent implant site pain (n = 5, 3.8%), generator/lead dislodgment (n = 5, 3.8%), malfunctioning device (n = 3, 2.3%), and hematoma (n = 1, 0.7%). Reimplantation after the first and second stages was necessary in 2 (1.5%) and 3 patients (2.3%), respectively. The device removal rate was 2.2%. At a median follow-up of 36.7 (range 1-84) months, the CCF-FIS significantly improved from a preoperative baseline of 15.9 ± 2.98 to 5.2 ± 3.92 (95%CI: 15.46 vs 4.43; p < 0.0001). Overall, 90% of patients rated their improvement as "significant". CONCLUSIONS: Sacral nerve stimulation for FI is safe and efficient, even in less wealthy or less developed countries.
Asunto(s)
Terapia por Estimulación Eléctrica/métodos , Incontinencia Fecal/terapia , Sacro/inervación , Adulto , Anciano , Anciano de 80 o más Años , Remoción de Dispositivos/estadística & datos numéricos , Electrodos Implantados , Femenino , Humanos , América Latina/epidemiología , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Estudios Retrospectivos , Sacro/cirugía , Resultado del Tratamiento , Adulto JovenRESUMEN
The stomachs of 464 speckled guitarfish Rhinobatos glaucostigma were sampled from the south-eastern Gulf of California (GC) to determine diet composition. Numerical indices and prey-specific index of relative importance ((%I)PSIR ) were used to determine the feeding strategy of the species. An analysis of similarity (ANOSIM) was used to determine differences in diet with respect to sex, season (dry or rainy) and maturity stages (immature or mature). The diversity and niche breadth (by sex, season and maturity) and a general trophic level were determined. The overall diet was dominated by shrimps ((%I)PSIR = 43.47), amphipods ((%I)PSIR = 18.89) and crabs ((%I)PSIR = 18.07). ANOSIM demonstrated differences in the diet by maturity and season, but not by sex. Rainy and dry season diets were dominated by shrimps and amphipods, respectively. Immature specimens fed mainly on amphipods, whereas mature fish preferred shrimps and crabs. Rhinobatos glaucostigma showed a narrow niche breadth with an intermediary trophic level (TL = 3.72) and can be considered as a secondary consumer in the soft-bottom demersal community of the south-east GC. Understanding the feeding habits and trophic level of R. glaucostigma is vital to help identify the segments of the population vulnerable to overfishing by artisanal and industrial fisheries, and to aid in conservation and management of this elasmobranch.
Asunto(s)
Dieta/veterinaria , Elasmobranquios/fisiología , Conducta Alimentaria , Animales , Femenino , Cadena Alimentaria , Contenido Digestivo , Masculino , México , Estaciones del AñoRESUMEN
BACKGROUND: Therapeutic education programs are effective in several chronic conditions. However, evidence is lacking in multiple system atrophy (MSA). We aimed to assess efficacy and safety of a comprehensive therapeutic education program in people with MSA (PwMSA) and their caregivers. METHODS: In this prospective longitudinal study we included 16 PwMSA and their main caregivers in 4 groups of 4 dyads each. The program consisted of eight 60-min interdisciplinary sessions: introduction, orthostatic hypotension, speech therapy, gait and respiratory physiotherapy, psychological support, urinary dysfunction, occupational therapy/social work. UMSARS, NMSS, PDQ39, EQ5 and Zarit scales were administered at baseline and 6 months later. After each session participants filled-out a modified EduPark satisfaction questionnaire and a Likert scale. Educational material was generated for each session after suggestions by participants. RESULTS: At baseline PwMSA and caregivers were comparable in age and sex, with significant correlation between UMSARS-IV (disability) and PDQ39 (quality of life). Adherence to sessions was of 94,92 %. Total modified EduPark scores and Likert scales did not differ in PwMSA vs. caregivers, mild-moderate vs. severe-advanced cases or between genders. The significant difference in satisfaction across sessions (p = 0.03) was driven by higher scores in speech, respiratory and occupational therapy sessions. Longitudinally there was no significant worsening in any scale, nor a significant increase post-vs. pre-program in the number of consultations. CONCLUSIONS: The healthcare education program in MSA was feasible, satisfactory, and safe for patients and caregivers. The educational material of the program is being forwarded to incident MSA cases attending our clinic.
Asunto(s)
Cuidadores , Atrofia de Múltiples Sistemas , Calidad de Vida , Sistema de Registros , Humanos , Masculino , Femenino , Atrofia de Múltiples Sistemas/terapia , Atrofia de Múltiples Sistemas/rehabilitación , Persona de Mediana Edad , Estudios Longitudinales , Anciano , Cuidadores/psicología , Cuidadores/educación , Proyectos Piloto , Educación del Paciente como Asunto , Satisfacción del Paciente , Estudios ProspectivosRESUMEN
During the last decade, the veterinary anesthetics have gained popularity as recreational drugs. The aim of this study was to document the use of "anestecia de caballo" (xylazine) and its consequences among drug users in Puerto Rico. The study combined a cross-sectional survey with 89 drug users and two focus groups conducted in Mayagüez with frontline drug treatment providers. Drug users were recruited from communities of the San Juan metropolitan area using a variety of ethnographic and outreach strategies. A short questionnaire developed for the study collected information on sociodemographics, xylazine use, and its consequences. The two focus groups were conducted to discuss the details related to xylazine use, its consequences, and utilization awareness. The sample comprised 63 males (70.8%) and 26 females with a mean age of 37.2 years. The mean number of years of drug use was 14.3, with a mean frequency of drug use of 5.9 times daily. More than 65% reported speedball as the principal drug of use. The prevalence of xylazine use was 80.7%. More than 42% of the sample used xylazine in a mixture with speedball. The main route of administration of xylazine was injection but 14% reported the use of xylazine by inhalation. More than 35% of the sample reported skin lesions and 21.1% reported at least one overdose episode. Multiple logistic regression analysis revealed that males (OR = 3.47, CI = 1.10-12.00) and those who reported speedball as their main drug of use (OR = 9.34, CI = 2.51-34.70) were significantly more likely to be xylazine users. Focus groups revealed that drug users claimed to recognize the presence of xylaxine in a mixture of speedball based on its effects, taste, the color of the drug (dark brown), and its odor. In conclusion, the use of xylazine among drug users in Puerto Rico seems to be an emerging trend with potentially serious health consequences.
Asunto(s)
Hipnóticos y Sedantes , Abuso de Sustancias por Vía Intravenosa/epidemiología , Trastornos Relacionados con Sustancias/epidemiología , Xilazina , Administración por Inhalación , Adulto , Cocaína/administración & dosificación , Estudios Transversales , Combinación de Medicamentos , Femenino , Grupos Focales , Heroína/administración & dosificación , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Puerto Rico/epidemiología , Úlcera Cutánea/etiología , Encuestas y Cuestionarios , Adulto JovenRESUMEN
The Asociación Mexicana de Hepatología A.C. carried out the Consensus on the Management of Complications of Cirrhosis of the Liver in Pediatrics to provide physicians with useful information for treating said complications. A group of pediatric gastroenterologists and experts in nutrition, nephrology, and infectious diseases participated and reviewed the medical literature. The Delphi method was applied to obtain the level of agreement on the statements that were formulated. The statements were sent to the participants to be analyzed and voted upon, after which they were discussed in virtual sessions, and the final versions were produced. The aim of the consensus results was to issue indications for the management of pediatric patients with liver cirrhosis, to prevent or control complications.
Asunto(s)
Cirrosis Hepática , Pediatría , Humanos , Niño , Consenso , Cirrosis Hepática/complicaciones , Cirrosis Hepática/terapiaRESUMEN
CHD8 is a chromatin remodeling ATPase of the SNF2 family. We found that depletion of CHD8 impairs cell proliferation. In order to identify CHD8 target genes, we performed a transcriptomic analysis of CHD8-depleted cells, finding out that CHD8 controls the expression of cyclin E2 (CCNE2) and thymidylate synthetase (TYMS), two genes expressed in the G1/S transition of the cell cycle. CHD8 was also able to co-activate the CCNE2 promoter in transient transfection experiments. Chromatin immunoprecipitation experiments demonstrated that CHD8 binds directly to the 5' region of both CCNE2 and TYMS genes. Interestingly, both RNA polymerase II (RNAPII) and CHD8 bind constitutively to the 5' promoter-proximal region of CCNE2, regardless of the cell-cycle phase and, therefore, of the expression of CCNE2. The tandem chromodomains of CHD8 bind in vitro specifically to histone H3 di-methylated at lysine 4. However, CHD8 depletion does not affect the methylation levels of this residue. We also show that CHD8 associates with the elongating form of RNAPII, which is phosphorylated in its carboxy-terminal domain (CTD). Furthermore, CHD8-depleted cells are hypersensitive to drugs that inhibit RNAPII phosphorylation at serine 2, suggesting that CHD8 is required for an early step of the RNAPII transcription cycle.
Asunto(s)
Ciclinas/genética , Proteínas de Unión al ADN/metabolismo , Regulación de la Expresión Génica , ARN Polimerasa II/metabolismo , Factores de Transcripción/metabolismo , Línea Celular Tumoral , Proliferación Celular , Ciclinas/biosíntesis , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/genética , Técnicas de Silenciamiento del Gen , Histonas/química , Histonas/metabolismo , Humanos , Fosforilación , Estructura Terciaria de Proteína , Timidilato Sintasa/biosíntesis , Timidilato Sintasa/genética , Factores de Transcripción/química , Factores de Transcripción/genéticaRESUMEN
Stage III non-small cell lung cancer (NSCLC) is a very heterogeneous disease that encompasses patients with resected, potentially resectable and unresectable tumours. To improve the prognostic capacity of the TNM classification, it has been agreed to divide stage III into sub-stages IIIA, IIIB and IIIC that have very different 5-year survival rates (36, 26 and 13%, respectively). Currently, it is considered that both staging and optimal treatment of stage III NSCLC requires the joint work of a multidisciplinary team of expert physicians within the tumour committee. To improve the care of patients with stage III NSCLC, different scientific societies involved in the diagnosis and treatment of this disease have agreed to issue a series of recommendations that can contribute to homogenise the management of this disease, and ultimately to improve patient care.
Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/terapia , Quimioradioterapia/mortalidad , Neoplasias Pulmonares/terapia , Escisión del Ganglio Linfático/mortalidad , Carcinoma de Pulmón de Células no Pequeñas/patología , Consenso , Manejo de la Enfermedad , Humanos , Neoplasias Pulmonares/patología , Estadificación de Neoplasias , Tasa de SupervivenciaRESUMEN
Biochemical and genetic evidence suggest that the SWI/SNF complex is involved in the remodeling of chromatin during gene activation. We have used antibodies specific against three human subunits of this complex to study its subnuclear localization, as well as its potential association with active chromatin and the nuclear skeleton. Immunofluorescence studies revealed a punctate nuclear labeling pattern that was excluded from the nucleoli and from regions of condensed chromatin. Dual labeling failed to reveal significant colocalization of BRG1 or hBRM proteins with RNA polymerase II or with nuclear speckles involved in splicing. Chromatin fractionation experiments showed that both soluble and insoluble active chromatin are enriched in the hSWI/SNF proteins as compared with bulk chromatin. hSWI/SNF proteins were also found to be associated with the nuclear matrix or nuclear scaffold, suggesting that a fraction of the hSWI/SNF complex could be involved in the chromatin organization properties associated with matrix attachment regions.
Asunto(s)
Cromatina/química , Proteínas de Unión al ADN/análisis , Matriz Nuclear/química , Proteínas Nucleares/análisis , Factores de Transcripción/análisis , Adenosina Trifosfato/farmacología , Proteínas Cromosómicas no Histona , ADN Helicasas , Proteínas de Unión al ADN/metabolismo , Inhibidores Enzimáticos/farmacología , Células HeLa , Humanos , Mitosis , Matriz Nuclear/metabolismo , Proteínas Nucleares/metabolismo , Inhibidores de Proteínas Quinasas , Proteína SMARCB1 , Factores de Transcripción/metabolismoRESUMEN
The recent discovery that the RING-finger domain is involved in mediating ubiquitin transfer from ubiquitin-conjugating enzymes to substrates have highlighted the importance of protein degradation through the ubiquitin-proteasome pathway in the regulation of different cellular processes. Two RING-finger-containing proteins, the promyelocytic leukemia protein (PML) from mammals and the constitutive photomorphogenic protein (COP1) from plants, show conspicuous similarities in their cellular distribution, dynamics and structure, indicating that they share a related function. Comparison of these two proteins suggests that they are involved in regulating the targeting of nuclear proteins to specific nuclear compartments for degradation through the ubiquitin-proteasome pathway.
Asunto(s)
Proteínas de Arabidopsis , Proteínas Portadoras/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas Nucleares , Proteínas de Plantas/metabolismo , Factores de Transcripción/metabolismo , Ubiquitina-Proteína Ligasas , Animales , Arabidopsis/metabolismo , Proteínas Portadoras/química , Cisteína Endopeptidasas/metabolismo , Ratones , Complejos Multienzimáticos/metabolismo , Proteínas de Neoplasias/química , Proteínas de Neoplasias/genética , Proteínas de Plantas/química , Proteína de la Leucemia Promielocítica , Complejo de la Endopetidasa Proteasomal , Factores de Transcripción/química , Factores de Transcripción/genética , Proteínas Supresoras de Tumor , Ubiquitinas/metabolismo , Dedos de ZincRESUMEN
The self-diffusion phenomenon in a two-dimensional dusty plasma at extremely strong (effective) magnetic fields is studied experimentally and by means of molecular dynamics simulations. In the experiment the high magnetic field is introduced by rotating the particle cloud and observing the particle trajectories in a corotating frame, which allows reaching effective magnetic fields up to 3000 T. The experimental results confirm the predictions of the simulations: (i) superdiffusive behavior is found at intermediate timescales and (ii) the dependence of the self-diffusion coefficient on the magnetic field is well reproduced.
RESUMEN
The BRAHMA (BRM) gene encodes the SNF2-type ATPase of the putative Arabidopsis thaliana SWI/SNF chromatin remodelling complex. This family of ATPases is characterized by the presence of a conserved catalytic domain and an arrangement of auxiliary domains, whose functions in the remodelling activity remains unclear. Here, we characterize, at the molecular and functional level, the carboxy-terminal part of Arabidopsis BRM. We have found three DNA-binding regions that bind various free DNA and nucleosomal probes with different specificity. One of these regions contains an AT-hook motif. The carboxy terminus also contains a bromodomain able to bind histones H3 and H4. We propose that this array of domains constitute a nucleosome interaction module that helps BRM to interact with its substrate. We also characterize an Arabidopsis mutant that expresses a BRM protein lacking the last 454 amino acid residues (BRM-DeltaC), encompassing the bromodomain and two of the three DNA-binding activities identified. This mutant displays an intermediate phenotype between those of the wild-type and a null allele mutant, suggesting that the nucleosome interaction module is required for the normal function of BRM but it is not essential for the remodelling activity of BRM-containing SWI/SNF complexes.
Asunto(s)
Adenosina Trifosfatasas/fisiología , Proteínas de Arabidopsis/fisiología , Arabidopsis/genética , Nucleosomas/metabolismo , Adenosina Trifosfatasas/genética , Secuencia de Aminoácidos , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Sitios de Unión , ADN Bacteriano/metabolismo , ADN de Plantas/metabolismo , Flores/crecimiento & desarrollo , Genes de Plantas , Histonas/metabolismo , Datos de Secuencia Molecular , Mutación , Estructura Terciaria de Proteína , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Alineación de SecuenciaRESUMEN
The plane wave expansion method is applied to determine the thickness of the ZnSe-ZnTe slabs in a semi-infinite dielectric grating in such a way that the maximum reflectivity of the system is obtained. In this way the potential of the ZnSe-ZnTe system for applications in CdSe ultra thin quantum well based monolithic II-VI Vertical Cavity Surface Emitting Laser for the green spectral region is demonstrated. A kinematic analysis of the thickness-dependent refraction at the boundary between a ZnSe-ZnTe semi-infinite one dimensional photonic crystal and a homogeneous material in transverse magnetic polarization and oblique incidence case is presented.
RESUMEN
We consider a bilevel optimisation approach for parameter learning in higher-order total variation image reconstruction models. Apart from the least squares cost functional, naturally used in bilevel learning, we propose and analyse an alternative cost based on a Huber-regularised TV seminorm. Differentiability properties of the solution operator are verified and a first-order optimality system is derived. Based on the adjoint information, a combined quasi-Newton/semismooth Newton algorithm is proposed for the numerical solution of the bilevel problems. Numerical experiments are carried out to show the suitability of our approach and the improved performance of the new cost functional. Thanks to the bilevel optimisation framework, also a detailed comparison between TGV 2 and ICTV is carried out, showing the advantages and shortcomings of both regularisers, depending on the structure of the processed images and their noise level.
RESUMEN
Therapeutic protocols in immunotherapy are usually proposed following the intuition and experience of the therapist. In order to deduce such protocols mathematical modeling, optimal control and simulations are used instead of the therapist's experience. Clinical efficacy of dendritic cell (DC) vaccines to cancer treatment is still unclear, since dendritic cells face several obstacles in the host environment, such as immunosuppression and poor transference to the lymph nodes reducing the vaccine effect. In view of that, we have created a mathematical murine model to measure the effects of dendritic cell injections admitting such obstacles. In addition, the model considers a therapy given by bolus injections of small duration as opposed to a continual dose. Doses timing defines the therapeutic protocols, which in turn are improved to minimize the tumor mass by an optimal control algorithm. We intend to supplement therapist's experience and intuition in the protocol's implementation. Experimental results made on mice infected with melanoma with and without therapy agree with the model. It is shown that the dendritic cells' percentage that manages to reach the lymph nodes has a crucial impact on the therapy outcome. This suggests that efforts in finding better methods to deliver DC vaccines should be pursued.
Asunto(s)
Vacunas contra el Cáncer , Células Dendríticas/inmunología , Inmunoterapia , Melanoma/terapia , Modelos Teóricos , Algoritmos , Animales , Simulación por Computador , Modelos Animales de Enfermedad , Ratones , Ratones Endogámicos C57BLRESUMEN
INTRODUCTION: The characteristics of social settings are increasingly being recognized as important factors influencing the health of individuals. This study examines the association of neighborhood physical and social disorganization with alcohol consumption in a sample of adolescents 12- to 15-years-old residing in communities of the San Juan metropolitan area with high availability of illicit drugs. METHODS: The sampling frame was developed encompassing all census sectors in three municipalities of the San Juan metropolitan area with outdoor illegal drug-selling areas operating within them. Consent from parents and their adolescent offspring was obtained from 691 of these households for a response rate of 96%. Alcohol use was measured by asking adolescents if they had consumed alcohol during the last 12 months. Neighborhood social disorganization included hearing gunfire in the neighborhood, seeing neighbors selling stolen merchandise and drugs, vandalism, neighbors using alcohol and drugs, and seeing persons carrying weapons. Neighborhood physical disorganization included the presence of abandoned vehicles and buildings in the neighborhood, graffiti, and places where people go to inject drugs. RESULTS: Multiple logistic regression analysis revealed that older participants were more likely to use alcohol. Neighborhood social disorder was significantly associated with alcohol use. The strong positive gradient between neighborhood social disorder and alcohol use remained highly significant after controlling by sociodemographic characteristics. In contrast, neighborhood physical disorder was not significantly associated with alcohol use. CONCLUSION: These findings suggest that social signs of neighborhood disorganization have a more direct influence over adolescents' behaviors than the physical signs. Health professionals need to be cognizant of the strong effects that social environments have on adolescents and develop strategies to address these when intervening with adolescents.
Asunto(s)
Consumo de Bebidas Alcohólicas/epidemiología , Características de la Residencia , Adolescente , Niño , Femenino , Humanos , Masculino , Puerto Rico/epidemiología , Factores SocioeconómicosRESUMEN
Glutamine synthetase (GS) from Synechocystis sp. PCC 6803 was inactivated in vivo by transferring cells from light to darkness or by incubation with the photosynthetic inhibitor 3-(3,4-dichlorophenyl)-1,1-dimethylurea but not with 2,5-dibromo-3-methyl-6-isopropyl-p-benzoquinone. Addition of glucose prevented both dark and 3-(3,4-dichlorophenyl)-1,1-dimethylurea GS inactivation. In a Synechocystis psbE-psbF mutant (T1297) lacking photosystem II, glucose was required to maintain active GS, even in the light. However, in nitrogen-starved T1297 cells the removal of glucose did not affect GS activity. The fact that dark-inactivated GS was reactivated in vitro by the same treatments that reactivate the ammonium-inactivated GS points out that both nitrogen metabolism and redox state of the cells lead to the same molecular regulatory mechanism in the control of GS activity. Using GS antibodies we detected that dark-inactivated GS displayed a different electrophoretic migration with respect to the active form in nondenaturing polyacrylamide gel electrophoresis but not in sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The possible pathway to modulate GS activity by the electron transport flow in Synechocystis cells is discussed.
RESUMEN
The glucocorticoid receptor interacting protein-1 (GRIP1) is a member of the steroid receptor coactivator (SRC) family of transcriptional regulators. Green fluorescent protein (GFP) fusions were made to full-length GRIP1, and a series of GRIP1 mutants lacking the defined regulatory regions and the intracellular distribution of these proteins was studied in HeLa cells. The distribution of GRIP1 was complex, ranging from diffuse nucleoplasmic to discrete intranuclear foci. Formation of these foci was dependent on the C-terminal region of GRIP1, which contains the two characterized transcriptional activation domains, AD1 and AD2. A subpopulation of GRIP1 foci associate with ND10s, small nuclear bodies that contain several proteins including PML, SP100, DAXX, and CREB-binding protein (CBP). Association with the ND10s is dependent on the AD1 of GRIP1, a region of the protein previously described as a CBP-interacting domain. The GRIP1 foci are enriched in components of the 26S proteasome, including the core 20S proteasome, PA28alpha, and ubiquitin. In addition, the irreversible proteasome inhibitor lactacystin induced an increase in the total fluorescence intensity of the GFP-GRIP1 expressing cells, demonstrating that GRIP1 is degraded by the proteasome. These findings suggest the intriguing possibility that degradation of GRIP1 by the 26S proteasome may be a key component of its regulation.
Asunto(s)
Acetilcisteína/análogos & derivados , Antígenos Nucleares , Estructuras del Núcleo Celular/metabolismo , Péptidos y Proteínas de Señalización Intracelular , Péptido Hidrolasas/metabolismo , Complejo de la Endopetidasa Proteasomal , Factores de Transcripción/metabolismo , Acetilcisteína/farmacología , Proteínas Adaptadoras Transductoras de Señales , Secuencia de Aminoácidos , Autoantígenos/metabolismo , Secuencia de Bases , Sitios de Unión , Proteína de Unión a CREB , Proteínas Portadoras/metabolismo , Proteínas Co-Represoras , Proteínas Fluorescentes Verdes , Células HeLa , Humanos , Proteínas Luminiscentes/genética , Proteínas Luminiscentes/metabolismo , Chaperonas Moleculares , Datos de Secuencia Molecular , Proteínas de Neoplasias/metabolismo , Proteínas Nucleares/metabolismo , Coactivador 2 del Receptor Nuclear , Coactivador 3 de Receptor Nuclear , Péptido Hidrolasas/efectos de los fármacos , Proteína de la Leucemia Promielocítica , Inhibidores de Proteasas/farmacología , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Eliminación de Secuencia , Transactivadores/metabolismo , Factores de Transcripción/genética , Proteínas Supresoras de Tumor , Ubiquitinas/metabolismoRESUMEN
HMG20A is a high mobility group (HMG) domain containing protein homologous to HMG20B, a core subunit of the Lys-specific demethylase 1/REST co-repressor 1 (LSD1-CoREST) histone demethylase complex. Here, we show that HMG20A can replace HMG20B and, therefore, they are mutually exclusive subunits of the complex. Both proteins interact through a coiled-coil domain with BHC80, another subunit of the LSD1-CoREST complex. To investigate the functional differences between the two proteins, we performed transcriptomic analysis of HMG20A- and HMG20B-depleted cells. Analysis of the misregulated genes in HMG20A-knockdown cells evidenced a high proportion of genes related to the epithelial-to-mesenchymal transition (EMT) process. EMT occurs during embryonic development or during the course of malignant cancer progression and consists in the dynamic and reversible transitions between epithelial and mesenchymal phenotypes. We show that HMG20A together with LSD1 are required for SNAI1-dependent repression of epithelial genes and for (transforming growth factor ß) TGF-ß-triggered EMT. Importantly, HMG20A-depleted cells displayed reduced binding of LSD1 to epithelial gene promoters and increased methylation of lysine 4 of histone H3, suggesting a role of HMG20A in recruiting or in stabilizing the complex at the chromatin. SNAI1 and the TGF-ß-related transcription factor SMAD4 were found to be associated with the LSD1-CoREST complex containing HMG20A. Furthermore, we show that HMG20A-depleted cells displayed reduced motility and invasion activity. Finally, we show that expression of HMG20A correlates positively with mesenchymal markers and negatively with epithelial markers in human tumor samples. Taken together, our data demonstrate that HMG20A is essential for the mesenchymal phenotype.