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1.
J Gastrointest Cancer ; 55(2): 511-518, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38165605

RESUMEN

BACKGROUND: To investigate the correlation between preoperative malnutrition and perioperative variables in patients with hepatocellular carcinoma (HCC) and to analyze the risk factors of complications after HCC resection. METHODS: All patients who underwent hepatectomy because of HCC in the First Affiliated Hospital of Chongqing Medical University from June 1, 2018, to December 1, 2021, were analyzed retrospectively. Preoperative malnutrition was defined as body mass index (BMI) < 18.5 kg/m2 or serum albumin level < 3.5 g/dL within 30 days before operation. RESULTS: A total of 415 patients with HCC hepatectomy were included, and 75 (18.1%) were classified as malnutrition group. In the malnutrition group, blood loss (662.1 ± 748.1 VS 404.6 ± 681.9, P = 0.002), transfusion rate (36.0% VS 13.5%, P < 0.001), postoperative hospital stays (13.3 ± 9.6 VS 10.1 ± 4.2, P < 0.001), 30-day postoperative mortality (4.0 VS 0.6%, P = 0.043), complications rate (68% VS 34.8%, P < 0.001), and severe complication rate (17.3% VS 2.4%, P < 0.001) were significantly higher than those in the well-nourished group. Multivariate analysis showed that age (HR 1.037, 95% CI 1.015-1.059, P = 0.001), preoperative malnutrition (HR 2.933, 95% CI 1.515-5.679, P = 0.001), simultaneous cholecystectomy (HR 2.004, 95% CI 1.168-3.440, P = 0.012), cirrhosis (HR 4.997, 95% CI 2.864-8.718, P < 0.001), and transfusion (HR 5.166, 95% CI 2.272-11.748, P < 0.001) were independent risk factors for postoperative complications. In addition, preoperative malnutrition (HR 8.209, 95% CI 2.711-24.864, P < 0.001) and operation time (HR 1.088, 95% CI 1.003-1.103, P = 0.004) were independent risk factors for severe complications. CONCLUSION: Preoperative malnutrition can adversely affect the outcome of HCC resection. For patients with advanced age, cirrhosis, and malnutrition, preoperative planning is very important, and we should be more careful during the operation to avoid transfusion caused by bleeding and not to carry out preventive cholecystectomy, which are helpful to reduce the occurrence of postoperative complications.


Asunto(s)
Índice de Masa Corporal , Carcinoma Hepatocelular , Hepatectomía , Neoplasias Hepáticas , Desnutrición , Complicaciones Posoperatorias , Humanos , Carcinoma Hepatocelular/cirugía , Carcinoma Hepatocelular/complicaciones , Masculino , Femenino , Neoplasias Hepáticas/cirugía , Neoplasias Hepáticas/complicaciones , Persona de Mediana Edad , Factores de Riesgo , Desnutrición/complicaciones , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Estudios Retrospectivos , Hepatectomía/efectos adversos , Anciano , Albúmina Sérica/análisis , Periodo Preoperatorio , Adulto
2.
Noncoding RNA Res ; 9(1): 194-202, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38125756

RESUMEN

Cholangiocarcinoma is a highly aggressive cancer with a dismal prognosis and limited resectability. Chemotherapy has demonstrated tremendous benefits for patients with advanced and inoperable cancer, but drug resistance poses a significant obstacle. Despite recent progress in cancer therapy, the mechanisms driving drug resistance are multifaceted and not completely comprehended. Non-coding RNA refers to RNA molecules that are endogenous and do not code for proteins. Particularly microRNAs, long non-coding RNAs, circular RNAs, are widely acknowledged to be involved in cancer initiation, proliferation, and metastasis. Recently, evidences suggests that abnormal expression of non-coding RNAs contributes to resistance to different type of cancer therapies in cholangiocarcinoma. This occurs via the rewiring of signaling pathways including the reduction of anticancer drugs, apoptosis, interaction between cholangiocarcinoma and tumor-infiltrating immune cells, and cancer stemness. Thus, our review aims to demonstrate the potential of targeting non-coding RNA to override drug resistance and summarize the molecular mechanisms of how non-coding RNA contributes to drug resistance in cholangiocarcinoma.

3.
Front Cell Dev Biol ; 11: 1179077, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37601106

RESUMEN

Currently, liver transplantation has reached a level of maturity where it is considered an effective treatment for end-stage liver disease and can significantly prolong the survival time of patients. However, acute and chronic rejection remain major obstacles to its efficacy. Although long-term use of immunosuppressants can prevent rejection, it is associated with serious side effects and significant economic burden for patients. Therefore, the investigation of induced immune tolerance holds crucial theoretical significance and socio-economic value. In fact, the establishment of immune tolerance in liver transplantation is intricately linked to the unique innate immune system of the liver. Kupffer cells, as a crucial component of this system, play a pivotal role in maintaining the delicate balance between inflammatory response and immune tolerance following liver transplantation. The important roles of different functions of Kupffer cells, such as phagocytosis, cell polarization, antigen presentation and cell membrane proteins, in the establishment of immune tolerance after transplantation is comprehensively summarized in this paper. Providing theoretical basis for further study and clinical application of Kupffer cells in liver transplantation.

4.
Front Plant Sci ; 13: 914103, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36275594

RESUMEN

Cadmium (Cd) contamination of agricultural soils poses a potential public health issue for humans. Phytoremediation-based accumulating plants are an effective and sustainable technology for Cadmium remediation of contaminated agricultural soil. The rhizosphere microbiome can promote the growth and Cadmium accumulation in hyperaccumulators, but its taxonomic and functional traits remain elusive. The present study used two ecotypes of Sedum alfredii, an accumulating ecotype (AE) and a non-accumulating ecotype (NAE), as model plants to investigate the rhizosphere microbiome assemblages and influence on plant growth under high cadmium conditions. Our results showed that distinct root microbiomes assembled in association with both ecotypes of S. alfredii and that the assemblages were based largely on the lifestyles of the two ecotypes. In addition, we demonstrated that the functions of the microbes inhabiting the rhizosphere soils were closely associated with root-microbe interactions in both ecotypes of S. alfredii. Importantly, our results also demonstrated that the rhizosphere microbiome assembled in the AE rhizosphere soils contributed to plant growth and cadmium uptake under high cadmium conditions through functions such as nitrogen fixation, phosphorus solubilization, indole acetic acid (IAA) synthesis, and siderophore metabolism. However, this phenomenon was not clearly observed in the NAE. Our results suggest that the rhizosphere microbiome plays important roles in biogeochemical nutrient and metal cycling that can contribute to host plant fitness.

5.
Transplant Proc ; 54(7): 1881-1886, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35918193

RESUMEN

BACKGROUND: T cell immunoglobulin domain, and mucin domain-3 (Tim-3) is associated with immunosuppression, immune tolerance, and rejection after organ transplantation, but there are no reports of rejection after human liver transplantation. This study aimed to detect Tim-3 expression after liver transplantation to determine whether Tim-3 can be used as a noninvasive index to predict immune rejection. METHODS: Quantitative real-time polymerase chain reaction and enzyme-linked immunosorbent assay were performed on healthy people and patients with liver transplantation to detect Tim-3 and cytokines. Hepatic biochemical test was used to detect liver function. The study conforms to the provisions of the Declaration of Helsinki and Istanbul. RESULTS: The expression of Tim-3, alanine aminotransferase, and aspartate aminotransferase increased first and then decreased, whereas the cytokines showed upward trend. There was no significant difference in the expression of Tim-3 between preoperative patients and normal people (P > .05), whereas the expression of Tim-3 was significantly higher on the third day after operation than that before operation (P < .05). The expression of Tim-3, alanine aminotransferase, and aspartate aminotransferase peaked only once in most liver transplantation patients, but there were 3 patients that were exceptions. CONCLUSIONS: Tim-3 could be used as a potential biomarker to predict rejection after liver transplantation.


Asunto(s)
Receptor 2 Celular del Virus de la Hepatitis A , Trasplante de Hígado , Humanos , Alanina Transaminasa/metabolismo , Suero Antilinfocítico , Aspartato Aminotransferasas/metabolismo , Citocinas/metabolismo , Dominios de Inmunoglobulinas , Trasplante de Hígado/efectos adversos , Mucina 3 , Linfocitos T
6.
Nat Commun ; 12(1): 5389, 2021 09 10.
Artículo en Inglés | MEDLINE | ID: mdl-34508101

RESUMEN

Conditional overexpression of histone reader Tripartite motif containing protein 24 (TRIM24) in mouse mammary epithelia (Trim24COE) drives spontaneous development of mammary carcinosarcoma tumors, lacking ER, PR and HER2. Human carcinosarcomas or metaplastic breast cancers (MpBC) are a rare, chemorefractory subclass of triple-negative breast cancers (TNBC). Comparison of Trim24COE metaplastic carcinosarcoma morphology, TRIM24 protein levels and a derived Trim24COE gene signature reveals strong correlation with human MpBC tumors and MpBC patient-derived xenograft (PDX) models. Global and single-cell tumor profiling reveal Met as a direct oncogenic target of TRIM24, leading to aberrant PI3K/mTOR activation. Here, we find that pharmacological inhibition of these pathways in primary Trim24COE tumor cells and TRIM24-PROTAC treatment of MpBC TNBC PDX tumorspheres decreased cellular viability, suggesting potential in therapeutically targeting TRIM24 and its regulated pathways in TRIM24-expressing TNBC.


Asunto(s)
Carcinosarcoma/genética , Proteínas Portadoras/genética , Neoplasias Mamarias Experimentales/genética , Proteínas Nucleares/genética , Factores de Transcripción/genética , Neoplasias de la Mama Triple Negativas/genética , Animales , Mama/patología , Carcinosarcoma/patología , Proteínas Portadoras/metabolismo , Ensayos Clínicos como Asunto , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Glándulas Mamarias Animales/patología , Neoplasias Mamarias Experimentales/patología , Ratones , Ratones Transgénicos , Proteínas Nucleares/metabolismo , Cultivo Primario de Células , Proteínas Proto-Oncogénicas c-met/genética , RNA-Seq , Análisis de la Célula Individual , Factores de Transcripción/metabolismo , Neoplasias de la Mama Triple Negativas/patología , Secuenciación Completa del Genoma , Ensayos Antitumor por Modelo de Xenoinjerto
7.
Int J Med Sci ; 18(14): 3097-3105, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34400880

RESUMEN

Emerging evidence revealed that UHRF2 was implicated in a variety of human diseases, especially in cancer. However, the biological function, clinical significance and underly mechanisms of UHRF2 in hepatocellular carcinoma (HCC) is largely unknown. We analyzed the expression of UHRF2 in 371 HCC tissues and 50 para-cancerous tissues of TCGA database. We found that UHRF2 was significantly upregulated in HCC tissues, which was further confirmed in HCC cells and tissues by western blot. More importantly, the level of UHRF2 was correlated with pathological grade and clinical stage, and the patients with high level of UHRF2 had lower overall survival, disease-free survival and higher recurrence rate than those with low UHRF2 level. Univariate and multivariate Cox regression analysis revealed that high level of UHRF2 might be an independent prognostic factor for HCC patients. Functional investigations suggested that ectopic expression of UHRF2 could promote the proliferation, migration and invasion of HCC cell lines, whereas knock down of UHRF2 exhibited an opposite effect. Additionally, gene set enrichment analysis indicated that ERBB signaling pathway was upregulated in patients with high level of UHRF2. Pearson correlation analysis indicated that the expression of UHRF2 was positively correlated with ErbB3 and its downstream targets SOS1, Ras and Raf-1. Furthermore, we found that overexpression of UHRF2 could upregulate the expression of ErbB3, SOS1, Ras and Raf-1. Our findings suggested that UHRF2 might accelerate HCC progression by upregulating ErbB3/Ras/Raf signaling pathway and it might serve as a diagnostic marker and therapeutic target for HCC patients.


Asunto(s)
Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Receptor ErbB-3/genética , Ubiquitina-Proteína Ligasas/metabolismo , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/cirugía , Progresión de la Enfermedad , Femenino , Regulación Neoplásica de la Expresión Génica , Técnicas de Silenciamiento del Gen , Células Hep G2 , Hepatectomía , Humanos , Hígado/patología , Hígado/cirugía , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/cirugía , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Estadificación de Neoplasias , Proteínas Proto-Oncogénicas c-raf/metabolismo , Receptor ErbB-3/metabolismo , Proteína SOS1/metabolismo , Transducción de Señal/genética , Ubiquitina-Proteína Ligasas/genética , Ubiquitinación/genética , Regulación hacia Arriba , Proteínas ras/metabolismo
8.
Endocrinology ; 162(8)2021 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-33963375

RESUMEN

The steroid receptor coactivator-1 (SRC-1) is a nuclear receptor co-activator, known to play key roles in both estrogen response in bone and in breast cancer metastases. We previously demonstrated that the P1272S single nucleotide polymorphism (SNP; P1272S; rs1804645) in SRC-1 decreases the activity of estrogen receptor in the presence of selective estrogen receptor modulators (SERMs) and that it is associated with a decrease in bone mineral density (BMD) after tamoxifen therapy, suggesting it may disrupt the agonist action of tamoxifen. Given such dual roles of SRC-1 in the bone microenvironment and in tumor cell-intrinsic phenotypes, we hypothesized that SRC-1 and a naturally occurring genetic variant, P1272S, may promote breast cancer bone metastases. We developed a syngeneic, knock-in mouse model to study if the SRC-1 SNP is critical for normal bone homeostasis and bone metastasis. Our data surprisingly reveal that the homozygous SRC-1 SNP knock-in increases tamoxifen-induced bone protection after ovariectomy. The presence of the SRC-1 SNP in mammary glands resulted in decreased expression levels of SRC-1 and reduced tumor burden after orthotopic injection of breast cancer cells not bearing the SRC-1 SNP, but increased metastases to the lungs in our syngeneic mouse model. Interestingly, the P1272S SNP identified in a small, exploratory cohort of bone metastases from breast cancer patients was significantly associated with earlier development of bone metastasis. This study demonstrates the importance of the P1272S SNP in both the effect of SERMs on BMD and the development of tumor in the bone.


Asunto(s)
Adenocarcinoma/secundario , Densidad Ósea/genética , Neoplasias Óseas/secundario , Neoplasias Mamarias Experimentales/patología , Coactivador 1 de Receptor Nuclear/fisiología , Adenocarcinoma/genética , Animales , Neoplasias Óseas/genética , Huesos/efectos de los fármacos , Huesos/patología , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Línea Celular Tumoral , Femenino , Técnicas de Sustitución del Gen , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/secundario , Neoplasias Mamarias Experimentales/genética , Ratones Transgénicos , Polimorfismo de Nucleótido Simple , Moduladores Selectivos de los Receptores de Estrógeno/farmacología , Tamoxifeno/farmacología
9.
Hepatol Int ; 15(3): 707-719, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33876395

RESUMEN

BACKGROUND AND AIMS: The major cause of Hepatocellular carcinoma (HCC) is acute or chronic infection caused by hepatotropic viruses and HBV infection is the main cause. UHRF2, a ubiquitin-protein ligase E3, is associated with cancer development. This study aimed to investigate the connection and mechanism between UHRF2 and HBV-associated HCC. METHODS: The expression of UHRF2 in human HBV-positive HCC tissues and paracancerous tissues was detected by western blot and tissue microarray. The effects of UHRF2 on invasion, migration and proliferation were detected in HBV-positive hepatoma cell lines. Furthermore, western blot, immunofluorescence, Co-immunoprecipitation and ubiquitination assays were used to explore the relationship and mechanism between UHRF2 and HBV-associated HCC. RESULTS: HBV-positive HCC tissues had higher UHRF2 expression levels than adjacent non-tumor tissues. The HBV-positive HCC patients with a low UHRF2 level in cancer tissues had longer overall and recurrence-free survival compared with those with a high UHRF2 level. UHRF2 induced invasion, migration and proliferation in human HBV-positive HCC cell lines HepG2.2.15 and Hep AD38(-). HBx, an encoding protein of HBV, maintained the stability of UHRF2 by blocking the ubiquitination of UHRF2. HBx up-regulated CDK2 expression through ETS1. UHRF2 bound to CDK2 directly and enhanced UHRF2 phosphorylation at serine 643. CONCLUSIONS: These results suggest that HBx-ETS1-CDK2-UHRF2 pathway plays an important role in the pathogenesis of HBV-associated HCC and represents new therapeutic targets for human HCC. CLINICAL TRIALS REGISTRATION: ChiCTR2000041416.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/genética , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica , Células Hep G2 , Virus de la Hepatitis B/metabolismo , Humanos , Neoplasias Hepáticas/genética , Fosforilación , Transactivadores/genética , Transactivadores/metabolismo , Ubiquitina-Proteína Ligasas , Ubiquitinación , Regulación hacia Arriba , Proteínas Reguladoras y Accesorias Virales
10.
Environ Pollut ; 268(Pt A): 115834, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33139093

RESUMEN

Thallium (Tl) is a highly toxic metalloid and is considered a priority pollutant by the US Environmental Protection Agency (EPA). Currently, few studies have investigated the distribution patterns of bacterial and fungal microbiomes in Tl-impacted environments. In this study, we used high-throughput sequencing to assess the bacterial and fungal profiles along a gradient of Tl contents in Tl mine waste rocks in southwestern China. Our results showed that Tl had an important, but different influence on the bacterial and fungal diversity indices. Using linear regression analysis, we furtherly divided the dominant bacterial and fungal groups into three distinct microbial sub-communities thriving at high, moderate, and low levels of Tl. Furthermore, our results also showed that Tl is also an important environmental variable that regulates the distribution patterns of ecological clusters and indicator genera. Interestingly, the microbial groups enriched in the samples with high Tl levels were mainly involved in metal and nutrient cycling. Taken together, our results have provided useful information about the responses of bacterial and fungal groups to Tl contamination.


Asunto(s)
Micobioma , Contaminantes del Suelo , Bacterias , China , Monitoreo del Ambiente , Contaminantes del Suelo/análisis , Talio/análisis
11.
Environ Microbiol ; 23(4): 1959-1971, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33145903

RESUMEN

The assemblage of root-associated microorganisms plays important roles in improving their capability to adapt to environmental stress. Metal(loid) hyperaccumulators exhibit disparate adaptive capability compared to that of non-hyperaccumulators when faced with elevated contents of metal(loid)s. However, knowledge of the assemblage of root microbes of hyperaccumulators and their ecological roles in plant growth is still scarce. The present study used Pteris vittata as a model plant to study the microbial assemblage and its beneficial role in plant growth. We demonstrated that the assemblage of microbes from the associated bulk soil to the root compartment was based on their lifestyles. We used metagenomic analysis and identified that the assembled microbes were primarily involved in root-microbe interactions in P. vittata root. Notably, we identified that the assembled root microbiome played an important role in As requisition, which promoted the fitness and growth of P. vittata. This study provides new insights into the root microbiome and potential valuable knowledge to understand how the root microbiome contributes to the fitness of its host.


Asunto(s)
Arsénico , Microbiota , Pteris , Contaminantes del Suelo , Biodegradación Ambiental , Raíces de Plantas , Contaminantes del Suelo/análisis
12.
Genes Dev ; 32(1): 58-69, 2018 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-29437725

RESUMEN

Histone acetylation is associated with active transcription in eukaryotic cells. It helps to open up the chromatin by neutralizing the positive charge of histone lysine residues and providing binding platforms for "reader" proteins. The bromodomain (BRD) has long been thought to be the sole protein module that recognizes acetylated histones. Recently, we identified the YEATS domain of AF9 (ALL1 fused gene from chromosome 9) as a novel acetyl-lysine-binding module and showed that the ENL (eleven-nineteen leukemia) YEATS domain is an essential acetyl-histone reader in acute myeloid leukemias. The human genome encodes four YEATS domain proteins, including GAS41, a component of chromatin remodelers responsible for H2A.Z deposition onto chromatin; however, the importance of the GAS41 YEATS domain in human cancer remains largely unknown. Here we report that GAS41 is frequently amplified in human non-small cell lung cancer (NSCLC) and is required for cancer cell proliferation, survival, and transformation. Biochemical and crystal structural studies demonstrate that GAS41 binds to histone H3 acetylated on H3K27 and H3K14, a specificity that is distinct from that of AF9 or ENL. ChIP-seq (chromatin immunoprecipitation [ChIP] followed by high-throughput sequencing) analyses in lung cancer cells reveal that GAS41 colocalizes with H3K27ac and H3K14ac on the promoters of actively transcribed genes. Depletion of GAS41 or disruption of the interaction between its YEATS domain and acetylated histones impairs the association of histone variant H2A.Z with chromatin and consequently suppresses cancer cell growth and survival both in vitro and in vivo. Overall, our study identifies GAS41 as a histone acetylation reader that promotes histone H2A.Z deposition in NSCLC.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Histonas/metabolismo , Neoplasias Pulmonares/metabolismo , Factores de Transcripción/metabolismo , Acetilación , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral , Proliferación Celular , Amplificación de Genes , Genes cdc , Histonas/fisiología , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Regiones Promotoras Genéticas , Dominios y Motivos de Interacción de Proteínas , Factores de Transcripción/química , Factores de Transcripción/genética , Factores de Transcripción/fisiología
13.
Nat Commun ; 8(1): 1088, 2017 10 20.
Artículo en Inglés | MEDLINE | ID: mdl-29057918

RESUMEN

Recognition of modified histones by "reader" proteins constitutes a key mechanism regulating diverse chromatin-associated processes important for normal and neoplastic development. We recently identified the YEATS domain as a novel acetyllysine-binding module; however, the functional importance of YEATS domain-containing proteins in human cancer remains largely unknown. Here, we show that the YEATS2 gene is highly amplified in human non-small cell lung cancer (NSCLC) and is required for cancer cell growth and survival. YEATS2 binds to acetylated histone H3 via its YEATS domain. The YEATS2-containing ATAC complex co-localizes with H3K27 acetylation (H3K27ac) on the promoters of actively transcribed genes. Depletion of YEATS2 or disruption of the interaction between its YEATS domain and acetylated histones reduces the ATAC complex-dependent promoter H3K9ac levels and deactivates the expression of essential genes. Taken together, our study identifies YEATS2 as a histone H3K27ac reader that regulates a transcriptional program essential for NSCLC tumorigenesis.


Asunto(s)
Carcinogénesis/genética , Carcinoma de Pulmón de Células no Pequeñas/fisiopatología , Histonas/metabolismo , Neoplasias Pulmonares/fisiopatología , Acetilación , Carcinoma de Pulmón de Células no Pequeñas/genética , Línea Celular Tumoral , Transformación Celular Neoplásica/genética , Regulación Neoplásica de la Expresión Génica/genética , Histonas/genética , Humanos , Neoplasias Pulmonares/genética , Procesamiento Proteico-Postraduccional/genética
14.
Artículo en Inglés | MEDLINE | ID: mdl-26396593

RESUMEN

BACKGROUND: Proteins that 'read' the histone code are central elements in epigenetic control and bromodomains, which bind acetyl-lysine motifs, are increasingly recognized as potential mediators of disease states. Notably, the first BET bromodomain-based therapies have entered clinical trials and there is a broad interest in dissecting the therapeutic relevance of other bromodomain-containing proteins in human disease. Typically, drug development is facilitated and expedited by high-throughput screening, where assays need to be sensitive, robust, cost-effective and scalable. However, for bromodomains, which lack catalytic activity that otherwise can be monitored (using classical enzymology), the development of cell-based, drug-target engagement assays has been challenging. Consequently, cell biochemical assays have lagged behind compared to other protein families (e.g., histone deacetylases and methyltransferases). RESULTS: Here, we present a suite of novel chromatin and histone-binding assays using AlphaLISA, in situ cell extraction and fluorescence-based, high-content imaging. First, using TRIM24 as an example, the homogenous, bead-based AlphaScreen technology was modified from a biochemical peptide-competition assay to measure binding of the TRIM24 bromodomain to endogenous histone H3 in cells (AlphaLISA). Second, a target agnostic, high-throughput imaging platform was developed to quantify the ability of chemical probes to dissociate endogenous proteins from chromatin/nuclear structures. While overall nuclear morphology is maintained, the procedure extracts soluble, non-chromatin-bound proteins from cells with drug-target displacement visualized by immunofluorescence (IF) or microscopy of fluorescent proteins. Pharmacological evaluation of these assays cross-validated their utility, sensitivity and robustness. Finally, using genetic and pharmacological approaches, we dissect domain contribution of TRIM24, BRD4, ATAD2 and SMARCA2 to chromatin binding illustrating the versatility/utility of the in situ cell extraction platform. CONCLUSIONS: In summary, we have developed two novel complementary and cell-based drug-target engagement assays, expanding the repertoire of pharmacodynamic assays for bromodomain tool compound development. These assays have been validated through a successful TRIM24 bromodomain inhibitor program, where a micromolar lead molecule (IACS-6558) was optimized using cell-based assays to yield the first single-digit nanomolar TRIM24 inhibitor (IACS-9571). Altogether, the assay platforms described herein are poised to accelerate the discovery and development of novel chemical probes to deliver on the promise of epigenetic-based therapies.

15.
Dis Model Mech ; 8(9): 1121-7, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26092125

RESUMEN

Scaffold attachment factors SAFB1 and SAFB2 are multifunctional proteins that share >70% sequence similarity. SAFB1-knockout (SAFB1(-/-)) mice display a high degree of lethality, severe growth retardation, and infertility in male mice. To assess the in vivo role of SAFB2, and to identify unique functions of the two paralogs, we generated SAFB2(-/-) mice. In stark contrast to SAFB1(-/-), SAFB2(-/-) offspring were born at expected Mendelian ratios and did not show any obvious defects in growth or fertility. Generation of paralog-specific antibodies allowed extensive expression analysis of SAFB1 and SAFB2 in mouse tissues, showing high expression of both SAFB1 and SAFB2 in the immune system, and in hormonally controlled tissues, with especially high expression of SAFB2 in the male reproductive tract. Further analysis showed a significantly increased testis weight in SAFB2(-/-) mice, which was associated with an increased number of Sertoli cells. Our data suggest that this is at least in part caused by alterations in androgen-receptor function and expression upon deletion of SAFB2. Thus, despite a high degree of sequence similarity, SAFB1(-/-) and SAFB2(-/-) mice do not totally phenocopy each other. SAFB2(-/-) mice are viable, and do not show any major defects, and our data suggest a role for SAFB2 in the differentiation and activity of Sertoli cells that deserves further study.


Asunto(s)
Proteínas Portadoras/genética , Proteínas de Unión al ADN/genética , Proteínas de Unión al ARN/genética , Animales , Peso Corporal , Proteínas Portadoras/fisiología , Diferenciación Celular , Proteínas de Unión al ADN/fisiología , Modelos Animales de Enfermedad , Exones , Femenino , Eliminación de Gen , Inmunohistoquímica , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Fenotipo , Proteínas de Unión al ARN/fisiología , Reproducción , Células de Sertoli/citología , Transducción de Señal
16.
J Hepatol ; 62(2): 371-9, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25281858

RESUMEN

BACKGROUND & AIMS: Aberrantly high expression of TRIM24 occurs in human cancers, including hepatocellular carcinoma. In contrast, TRIM24 in the mouse is reportedly a liver-specific tumour suppressor. To address this dichotomy and to uncover direct regulatory functions of TRIM24 in vivo, we developed a new mouse model that lacks expression of all Trim24 isoforms, as the previous model expressed normal levels of Trim24 lacking only exon 4. METHODS: To produce germline-deleted Trim24(dlE1) mice, deletion of the promoter and exon 1 of Trim24 was induced in Trim24(LoxP) mice by crossing with a zona pellucida 3-Cre line for global deletion. Liver-specific deletion (Trim24(hep)) was achieved by crossing with an albumin-Cre line. Phenotypic analyses were complemented by protein, gene-specific and global RNA expression analyses and quantitative chromatin immunoprecipitation. RESULTS: Global loss of Trim24 disrupted hepatic homeostasis in 100% of mice with highly significant, decreased expression of oxidation/reduction, steroid, fatty acid, and lipid metabolism genes, as well as increased expression of genes involved in unfolded protein response, endoplasmic reticulum stress and cell cycle pathways. Trim24(dlE1/dlE1) mice have markedly depleted visceral fat and, like Trim24(hep/hep) mice, spontaneously develop hepatic lipid-filled lesions, steatosis, hepatic injury, fibrosis and hepatocellular carcinoma. CONCLUSIONS: TRIM24, an epigenetic co-regulator of transcription, directly and indirectly represses hepatic lipid accumulation, inflammation, fibrosis and damage in the murine liver. Complete loss of Trim24 offers a model of human non-alcoholic fatty liver disease, steatosis, fibrosis and development of hepatocellular carcinoma in the absence of high-fat diet or obesity.


Asunto(s)
Carcinoma Hepatocelular/genética , Hígado Graso/genética , Regulación Neoplásica de la Expresión Génica , Lípidos/análisis , Neoplasias Hepáticas Experimentales/genética , Proteínas Nucleares/genética , ARN Neoplásico/genética , Factores de Transcripción/genética , Animales , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Progresión de la Enfermedad , Hígado Graso/metabolismo , Hígado Graso/patología , Humanos , Hígado/metabolismo , Hígado/patología , Neoplasias Hepáticas Experimentales/metabolismo , Neoplasias Hepáticas Experimentales/patología , Ratones , Ratones Noqueados , Proteínas Nucleares/biosíntesis , Reacción en Cadena de la Polimerasa , Factores de Transcripción/biosíntesis
17.
PLoS One ; 9(9): e107378, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25222846

RESUMEN

BACKGROUND: Because computed tomography (CT) has advantages for visualizing the manifestation of necrosis and local complications, a series of scoring systems based on CT manifestations have been developed for assessing the clinical outcomes of acute pancreatitis (AP), including the CT severity index (CTSI), modified CTSI, etc. Despite the internationally accepted CTSI having been successfully used to predict the overall mortality and disease severity of AP, recent literature has revealed the limitations of the CTSI. Using the Delphi method, we establish a new scoring system based on retrocrural space involvement (RCSI), and compared its effectiveness at evaluating the mortality and severity of AP with that of the CTSI. METHODS: We reviewed CT images of 257 patients with AP taken within 3-5 days of admission in 2012. The RCSI scoring system, which includes assessment of infectious conditions involving the retrocrural space and the adjacent pleural cavity, was established using the Delphi method. Two radiologists independently assessed the RCSI and CTSI scores. The predictive points of the RCSI and CTSI scoring systems in evaluating the mortality and severity of AP were estimated using receiver operating characteristic (ROC) curves. PRINCIPAL FINDINGS: The RCSI score can accurately predict the mortality and disease severity. The area under the ROC curve for the RCSI versus CTSI score was 0.962±0.011 versus 0.900±0.021 for predicting the mortality, and 0.888±0.025 versus 0.904±0.020 for predicting the severity of AP. Applying ROC analysis to our data showed that a RCSI score of 4 was the best cutoff value, above which mortality could be identified. CONCLUSION: The Delphi method was innovatively adopted to establish a scoring system to predict the clinical outcome of AP. The RCSI scoring system can predict the mortality of AP better than the CTSI system, and the severity of AP equally as well.


Asunto(s)
Pancreatitis/diagnóstico por imagen , Pancreatitis/patología , Tomografía Computarizada por Rayos X/métodos , Enfermedad Aguda , Adulto , Anciano , Anciano de 80 o más Años , Humanos , Persona de Mediana Edad , Pancreatitis/mortalidad , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Adulto Joven
18.
Nature ; 508(7495): 263-8, 2014 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-24590075

RESUMEN

Recognition of modified histones by 'reader' proteins plays a critical role in the regulation of chromatin. H3K36 trimethylation (H3K36me3) is deposited onto the nucleosomes in the transcribed regions after RNA polymerase II elongation. In yeast, this mark in turn recruits epigenetic regulators to reset the chromatin to a relatively repressive state, thus suppressing cryptic transcription. However, much less is known about the role of H3K36me3 in transcription regulation in mammals. This is further complicated by the transcription-coupled incorporation of the histone variant H3.3 in gene bodies. Here we show that the candidate tumour suppressor ZMYND11 specifically recognizes H3K36me3 on H3.3 (H3.3K36me3) and regulates RNA polymerase II elongation. Structural studies show that in addition to the trimethyl-lysine binding by an aromatic cage within the PWWP domain, the H3.3-dependent recognition is mediated by the encapsulation of the H3.3-specific 'Ser 31' residue in a composite pocket formed by the tandem bromo-PWWP domains of ZMYND11. Chromatin immunoprecipitation followed by sequencing shows a genome-wide co-localization of ZMYND11 with H3K36me3 and H3.3 in gene bodies, and its occupancy requires the pre-deposition of H3.3K36me3. Although ZMYND11 is associated with highly expressed genes, it functions as an unconventional transcription co-repressor by modulating RNA polymerase II at the elongation stage. ZMYND11 is critical for the repression of a transcriptional program that is essential for tumour cell growth; low expression levels of ZMYND11 in breast cancer patients correlate with worse prognosis. Consistently, overexpression of ZMYND11 suppresses cancer cell growth in vitro and tumour formation in mice. Together, this study identifies ZMYND11 as an H3.3-specific reader of H3K36me3 that links the histone-variant-mediated transcription elongation control to tumour suppression.


Asunto(s)
Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Proteínas Portadoras/metabolismo , Histonas/metabolismo , Lisina/metabolismo , ARN Polimerasa II/metabolismo , Elongación de la Transcripción Genética , Secuencia de Aminoácidos , Animales , Neoplasias de la Mama/metabolismo , Proteínas Portadoras/química , Proteínas de Ciclo Celular , Cromatina/genética , Cromatina/metabolismo , Proteínas Co-Represoras/química , Proteínas Co-Represoras/metabolismo , Cristalografía por Rayos X , Proteínas de Unión al ADN , Supervivencia sin Enfermedad , Femenino , Regulación Neoplásica de la Expresión Génica/genética , Histonas/química , Humanos , Metilación , Ratones , Ratones Desnudos , Modelos Moleculares , Datos de Secuencia Molecular , Oncogenes/genética , Pronóstico , Unión Proteica , Conformación Proteica , Estructura Terciaria de Proteína , Especificidad por Sustrato
19.
Sci Transl Med ; 6(229): 229ra41, 2014 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-24670685

RESUMEN

Resistance to aromatase inhibitors (AIs) is a major clinical problem in the treatment of estrogen receptor (ER)-positive breast cancer. In two breast cancer cell line models of AI resistance, we identified widespread DNA hyper- and hypomethylation, with enrichment for promoter hypermethylation of developmental genes. For the homeobox gene HOXC10, methylation occurred in a CpG shore, which overlapped with a functional ER binding site, causing repression of HOXC10 expression. Although short-term blockade of ER signaling caused relief of HOXC10 repression in both cell lines and breast tumors, it also resulted in concurrent recruitment of EZH2 and increased H3K27me3, ultimately transitioning to increased DNA methylation and silencing of HOXC10. Reduced HOXC10 in vitro and in xenografts resulted in decreased apoptosis and caused antiestrogen resistance. Supporting this, we used paired primary and metastatic breast cancer specimens to show that HOXC10 was reduced in tumors that recurred during AI treatment. We propose a model in which estrogen represses apoptotic and growth-inhibitory genes such as HOXC10, contributing to tumor survival, whereas AIs induce these genes to cause apoptosis and therapeutic benefit, but long-term AI treatment results in permanent repression of these genes via methylation and confers resistance. Therapies aimed at inhibiting AI-induced histone and DNA methylation may be beneficial in blocking or delaying AI resistance.


Asunto(s)
Neoplasias de la Mama/genética , Reprogramación Celular/genética , Resistencia a Antineoplásicos/genética , Epigénesis Genética/genética , Estrógenos/farmacología , Proteínas de Homeodominio/genética , Animales , Apoptosis/efectos de los fármacos , Apoptosis/genética , Inhibidores de la Aromatasa/farmacología , Inhibidores de la Aromatasa/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Movimiento Celular/efectos de los fármacos , Movimiento Celular/genética , Proliferación Celular/efectos de los fármacos , Reprogramación Celular/efectos de los fármacos , Metilación de ADN/efectos de los fármacos , Metilación de ADN/genética , Resistencia a Antineoplásicos/efectos de los fármacos , Epigénesis Genética/efectos de los fármacos , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Silenciador del Gen/efectos de los fármacos , Histonas/metabolismo , Proteínas de Homeodominio/metabolismo , Humanos , Células MCF-7 , Ratones , Recurrencia Local de Neoplasia/tratamiento farmacológico , Recurrencia Local de Neoplasia/genética , Recurrencia Local de Neoplasia/patología , Regiones Promotoras Genéticas , Ensayos Antitumor por Modelo de Xenoinjerto
20.
Breast Cancer Res Treat ; 136(1): 253-65, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23015261

RESUMEN

Silencing mediator of retinoic acid and thyroid hormone receptor (SMRT), also known as nuclear corepressor 2 (NCOR2) is a transcriptional corepressor for multiple members of the nuclear receptor superfamily of transcription factors, including estrogen receptor-α (ERα). In the classical model of corepressor action, SMRT binds to antiestrogen-bound ERα at target promoters and represses ERα transcriptional activity and gene expression. Herein SMRT mRNA and protein expression was examined in a panel of 30 breast cancer cell lines. Expression of both parameters was found to vary considerably amongst lines and the correlation between protein and mRNA expression was very poor (R (2) = 0.0775). Therefore, SMRT protein levels were examined by immunohistochemical staining of a tissue microarray of 866 patients with stage I-II breast cancer. Nuclear and cytoplasmic SMRT were scored separately according to the Allred score. The majority of tumors (67 %) were negative for cytoplasmic SMRT, which when detected was found at very low levels. In contrast, nuclear SMRT was broadly detected. There was no significant difference in time to recurrence (TTR) according to SMRT expression levels in the ERα-positive tamoxifen-treated patients (P = 0.297) but the difference was significant in the untreated patients (P = 0.01). In multivariate analysis, ERα-positive tamoxifen-untreated patients with high nuclear SMRT expression (SMRT 5-8, i.e., 2nd to 4th quartile) had a shorter TTR (HR = 1.94, 95 % CI, 1.24-3.04; P = 0.004) while there was no association with SMRT expression for ERα-positive tamoxifen-treated patients. There was no association between SMRT expression and overall survival for patients, regardless of whether they received tamoxifen. Thus while SMRT protein expression was not predictive of outcome after antiestrogen therapy, it may have value in predicting tumor recurrence in patients not receiving adjuvant tamoxifen therapy.


Asunto(s)
Neoplasias de la Mama , Regulación Neoplásica de la Expresión Génica , Co-Represor 2 de Receptor Nuclear/metabolismo , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Línea Celular Tumoral , Nucléolo Celular/genética , Nucléolo Celular/metabolismo , Receptor alfa de Estrógeno/metabolismo , Femenino , Humanos , Persona de Mediana Edad , Recurrencia Local de Neoplasia/genética , Recurrencia Local de Neoplasia/metabolismo , Recurrencia Local de Neoplasia/patología , Estadificación de Neoplasias , Co-Represor 2 de Receptor Nuclear/genética , Análisis de Supervivencia , Tamoxifeno/administración & dosificación , Análisis de Matrices Tisulares
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