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1.
Nat Immunol ; 22(11): 1403-1415, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34686867

RESUMEN

Tumor-associated macrophages (TAMs) display pro-tumorigenic phenotypes for supporting tumor progression in response to microenvironmental cues imposed by tumor and stromal cells. However, the underlying mechanisms by which tumor cells instruct TAM behavior remain elusive. Here, we uncover that tumor-cell-derived glucosylceramide stimulated unconventional endoplasmic reticulum (ER) stress responses by inducing reshuffling of lipid composition and saturation on the ER membrane in macrophages, which induced IRE1-mediated spliced XBP1 production and STAT3 activation. The cooperation of spliced XBP1 and STAT3 reinforced the pro-tumorigenic phenotype and expression of immunosuppressive genes. Ablation of XBP1 expression with genetic manipulation or ameliorating ER stress responses by facilitating LPCAT3-mediated incorporation of unsaturated lipids to the phosphatidylcholine hampered pro-tumorigenic phenotype and survival in TAMs. Together, we uncover the unexpected roles of tumor-cell-produced lipids that simultaneously orchestrate macrophage polarization and survival in tumors via induction of ER stress responses and reveal therapeutic targets for sustaining host antitumor immunity.


Asunto(s)
Estrés del Retículo Endoplásmico , Retículo Endoplásmico/metabolismo , Membranas Intracelulares/metabolismo , Activación de Macrófagos , Melanoma/metabolismo , Lípidos de la Membrana/metabolismo , Neoplasias Cutáneas/metabolismo , Macrófagos Asociados a Tumores/metabolismo , Animales , Línea Celular Tumoral , Supervivencia Celular , Retículo Endoplásmico/ultraestructura , Glucosilceramidasa/metabolismo , Membranas Intracelulares/ultraestructura , Melanoma/genética , Melanoma/ultraestructura , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Ratones Endogámicos C57BL , Ratones Transgénicos , Fenotipo , Fosforilación , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Factor de Transcripción STAT3/genética , Factor de Transcripción STAT3/metabolismo , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/ultraestructura , Escape del Tumor , Microambiente Tumoral , Macrófagos Asociados a Tumores/ultraestructura , Proteína 1 de Unión a la X-Box/genética , Proteína 1 de Unión a la X-Box/metabolismo
2.
Nat Immunol ; 21(12): 1540-1551, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33020660

RESUMEN

The metabolic challenges present in tumors attenuate the metabolic fitness and antitumor activity of tumor-infiltrating T lymphocytes (TILs). However, it remains unclear whether persistent metabolic insufficiency can imprint permanent T cell dysfunction. We found that TILs accumulated depolarized mitochondria as a result of decreased mitophagy activity and displayed functional, transcriptomic and epigenetic characteristics of terminally exhausted T cells. Mechanistically, reduced mitochondrial fitness in TILs was induced by the coordination of T cell receptor stimulation, microenvironmental stressors and PD-1 signaling. Enforced accumulation of depolarized mitochondria with pharmacological inhibitors induced epigenetic reprogramming toward terminal exhaustion, indicating that mitochondrial deregulation caused T cell exhaustion. Furthermore, supplementation with nicotinamide riboside enhanced T cell mitochondrial fitness and improved responsiveness to anti-PD-1 treatment. Together, our results reveal insights into how mitochondrial dynamics and quality orchestrate T cell antitumor responses and commitment to the exhaustion program.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , Recuento de Linfocitos , Linfocitos Infiltrantes de Tumor/inmunología , Linfocitos Infiltrantes de Tumor/metabolismo , Dinámicas Mitocondriales/inmunología , Biomarcadores , Epigénesis Genética , Epigenómica , Humanos , Mitocondrias/efectos de los fármacos , Mitocondrias/inmunología , Mitocondrias/metabolismo , Mitocondrias/ultraestructura , Mitofagia , Neoplasias/inmunología , Neoplasias/metabolismo , Neoplasias/patología , Neoplasias/terapia , Niacinamida/farmacología , Receptor de Muerte Celular Programada 1/metabolismo , Receptores de Antígenos de Linfocitos T/metabolismo , Transducción de Señal , Estrés Fisiológico , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo
3.
Nat Immunol ; 18(8): 921-930, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28650481

RESUMEN

Germinal centers (GCs) support high-affinity, long-lived humoral immunity. How memory B cells develop in GCs is not clear. Through the use of a cell-cycle-reporting system, we identified GC-derived memory precursor cells (GC-MP cells) that had quit cycling and reached G0 phase while in the GC, exhibited memory-associated phenotypes with signs of affinity maturation and localized toward the GC border. After being transferred into adoptive hosts, GC-MP cells reconstituted a secondary response like genuine memory B cells. GC-MP cells expressed the interleukin 9 (IL-9) receptor and responded to IL-9. Acute treatment with IL-9 or antibody to IL-9 accelerated or retarded the positioning of GC-MP cells toward the GC edge and exit from the GC, and enhanced or inhibited the development of memory B cells, which required B cell-intrinsic responsiveness to IL-9. Follicular helper T cells (TFH cells) produced IL-9, and deletion of IL-9 from T cells or, more specifically, from GC TFH cells led to impaired memory formation of B cells. Therefore, the GC development of memory B cells is promoted by TFH cell-derived IL-9.


Asunto(s)
Subgrupos de Linfocitos B/inmunología , Linfocitos B/inmunología , Centro Germinal/inmunología , Memoria Inmunológica/inmunología , Interleucina-9/inmunología , Linfocitos T Colaboradores-Inductores/inmunología , Animales , Subgrupos de Linfocitos B/efectos de los fármacos , Linfocitos B/efectos de los fármacos , Células Cultivadas , Citometría de Flujo , Técnica del Anticuerpo Fluorescente , Técnicas de Silenciamiento del Gen , Memoria Inmunológica/efectos de los fármacos , Técnicas In Vitro , Interleucina-9/farmacología , Tejido Linfoide , Ratones , Ratones Noqueados , Reacción en Cadena en Tiempo Real de la Polimerasa
4.
Cell Mol Life Sci ; 80(5): 120, 2023 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-37041420

RESUMEN

BACKGROUND: Hypoxia-inducible factors (HIFs) are the most essential endogenous transcription factors in the hypoxic microenvironment and regulate multiple genes involved in the proliferation, migration, invasion, and EMT of hepatocellular carcinoma (HCC) cells. However, the regulatory mechanism of HIFs in driving HCC progression remains poorly understood. METHODS: Gain- and loss-of-function experiments were carried out to investigate the role of TMEM237 in vitro and in vivo. The molecular mechanisms involved in HIF-1α-induced TMEM237 expression and TMEM237-mediated enhancement of HCC progression were confirmed by luciferase reporter, ChIP, IP-MS and Co-IP assays. RESULTS: TMEM237 was identified as a novel hypoxia-responsive gene in HCC. HIF-1α directly bound to the promoter of TMEM237 to transactivate its expression. The overexpression of TMEM237 was frequently detected in HCC and associated with poor clinical outcomes in patients. TMEM237 facilitated the proliferation, migration, invasion, and EMT of HCC cells and promoted tumor growth and metastasis in mice. TMEM237 interacted with NPHP1 and strengthened the interaction between NPHP1 and Pyk2 to trigger the phosphorylation of Pyk2 and ERK1/2, thereby contributing to HCC progression. The TMEM237/NPHP1 axis mediates hypoxia-induced activation of the Pyk2/ERK1/2 pathway in HCC cells. CONCLUSIONS: Our study demonstrated that HIF-1α-activated TMEM237 interacted with NPHP1 to activate the Pyk2/ERK pathway, thereby promoting HCC progression.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animales , Ratones , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Carcinoma Hepatocelular/genética , Línea Celular Tumoral , Proteínas del Citoesqueleto/metabolismo , Quinasa 2 de Adhesión Focal/metabolismo , Hipoxia/genética , Neoplasias Hepáticas/metabolismo , Sistema de Señalización de MAP Quinasas , Microambiente Tumoral , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo
5.
EMBO J ; 37(23)2018 12 03.
Artículo en Inglés | MEDLINE | ID: mdl-30158112

RESUMEN

Elevated expression of RNA binding protein HNRNPC has been reported in cancer cells, while the essentialness and functions of HNRNPC in tumors were not clear. We showed that repression of HNRNPC in the breast cancer cells MCF7 and T47D inhibited cell proliferation and tumor growth. Our computational inference of the key pathways and extensive experimental investigations revealed that the cascade of interferon responses mediated by RIG-I was responsible for such tumor-inhibitory effect. Interestingly, repression of HNRNPC resulted in accumulation of endogenous double-stranded RNA (dsRNA), the binding ligand of RIG-I. These up-regulated dsRNA species were highly enriched by Alu sequences and mostly originated from pre-mRNA introns that harbor the known HNRNPC binding sites. Such source of dsRNA is different than the recently well-characterized endogenous retroviruses that encode dsRNA In summary, essentialness of HNRNPC in the breast cancer cells was attributed to its function in controlling the endogenous dsRNA and the down-stream interferon response. This is a novel extension from the previous understandings about HNRNPC in binding with introns and regulating RNA splicing.


Asunto(s)
Neoplasias de la Mama/metabolismo , Regulación Neoplásica de la Expresión Génica , Ribonucleoproteína Heterogénea-Nuclear Grupo C/biosíntesis , Interferones/metabolismo , Proteínas de Neoplasias/biosíntesis , ARN Bicatenario/biosíntesis , ARN Neoplásico/biosíntesis , Regulación hacia Arriba , Animales , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Femenino , Ribonucleoproteína Heterogénea-Nuclear Grupo C/genética , Humanos , Interferones/genética , Intrones , Células MCF-7 , Ratones , Proteínas de Neoplasias/genética , Empalme del ARN , ARN Bicatenario/genética , ARN Neoplásico/genética , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo
6.
BMC Bioinformatics ; 21(1): 340, 2020 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-32738892

RESUMEN

BACKGROUND: Ribosome profiling has been widely used for studies of translation under a large variety of cellular and physiological contexts. Many of these studies have greatly benefitted from a series of data-mining tools designed for dissection of the translatome from different aspects. However, as the studies of translation advance quickly, the current toolbox still falls in short, and more specialized tools are in urgent need for deeper and more efficient mining of the important and new features of the translation landscapes. RESULTS: Here, we present RiboMiner, a bioinformatics toolset for mining of multi-dimensional features of the translatome with ribosome profiling data. RiboMiner performs extensive quality assessment of the data and integrates a spectrum of tools for various metagene analyses of the ribosome footprints and for detailed analyses of multiple features related to translation regulation. Visualizations of all the results are available. Many of these analyses have not been provided by previous methods. RiboMiner is highly flexible, as the pipeline could be easily adapted and customized for different scopes and targets of the studies. CONCLUSIONS: Applications of RiboMiner on two published datasets did not only reproduced the main results reported before, but also generated novel insights into the translation regulation processes. Therefore, being complementary to the current tools, RiboMiner could be a valuable resource for dissections of the translation landscapes and the translation regulations by mining the ribosome profiling data more comprehensively and with higher resolution. RiboMiner is freely available at https://github.com/xryanglab/RiboMiner and https://pypi.org/project/RiboMiner .


Asunto(s)
Biología Computacional/métodos , Biosíntesis de Proteínas , Ribosomas/metabolismo , Programas Informáticos , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Aminoácidos/genética , Codón/genética , Análisis de Datos , Minería de Datos
7.
Nucleic Acids Res ; 46(10): e61, 2018 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-29538776

RESUMEN

By capturing and sequencing the RNA fragments protected by translating ribosomes, ribosome profiling provides snapshots of translation at subcodon resolution. The growing needs for comprehensive annotation and characterization of the context-dependent translatomes are calling for an efficient and unbiased method to accurately recover the signal of active translation from the ribosome profiling data. Here we present our new method, RiboCode, for such purpose. Being tested with simulated and real ribosome profiling data, and validated with cell type-specific QTI-seq and mass spectrometry data, RiboCode exhibits superior efficiency, sensitivity, and accuracy for de novo annotation of the translatome, which covers various types of ORFs in the previously annotated coding and non-coding regions. As an example, RiboCode was applied to assemble the context-specific translatomes of yeast under normal and stress conditions. Comparisons among these translatomes revealed stress-activated novel upstream and downstream ORFs, some of which are associated with translational dysregulations of the annotated main ORFs under the stress conditions.


Asunto(s)
Biología Computacional/métodos , Sistemas de Lectura Abierta , Biosíntesis de Proteínas , Ribosomas/genética , Animales , Bases de Datos Genéticas , Células HEK293 , Respuesta al Choque Térmico/genética , Humanos , Hígado/fisiología , Ratones , Anotación de Secuencia Molecular , Estrés Oxidativo/genética , Reproducibilidad de los Resultados , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/fisiología , Sensibilidad y Especificidad , Espectrometría de Masas en Tándem , Pez Cebra/genética
8.
Oncogenesis ; 13(1): 31, 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39266549

RESUMEN

BAP1, BRCA1-Associated Protein 1, serves as a novel tumor suppressor through the deubiquitination of monoubiquitination of H2A and subsequent gene transcriptional regulation. Regulated cell death like apoptosis or ferroptosis is considered an essential mechanism mediating tumor suppression. Previous reports, including ours, have demonstrated that BAP1 could promote apoptosis and ferroptosis to inhibit tumor development. Whether BAP1 regulated additional types of cell death remains unclear. Disulfidptosis is a recently identified novel cell death mode characterized by aberrant accumulation of intracellular disulfide (e.g., cystine) and depletion of NADPH. In this study, we first demonstrated that BAP1 could significantly protect disulfidptosis induced by glucose starvation, which is validated by various cell death inhibitors and the accumulation of disulfide bonds in the cytoskeleton proteins. BAP1 is known to inhibit SLC7A11 expression. We found that the protective effect of BAP1 against disulfidptosis was counteracted when overexpressing SLC7A11 or adding additional cystine. Conversely, BAP1-mediated suppression of disulfidptosis was largely abrogated when SLC7A11-mediated cystine uptake was inhibited by the knockout of SLC7A11 or erastin treatment. Besides, high BAP1 expression showed lower NADP+/NADPH levels, which might confer resistance to disulfidptosis. Consistent with these observations, the expression level of BAP1 was also positively correlated with NADPH-related genes in KIRC patients, though the underlying mechanism mediating NADPH regulation remains further investigation. In summary, our results revealed the role of BAP1 in the regulation disulfidptosis and provided new insights into the understanding of disulfidptosis in tumor development.

9.
Cancer Lett ; 589: 216832, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38537774

RESUMEN

Yes-associated protein (YAP) is an essential driver of hepatocellular carcinoma (HCC) progression and the ubiquitin-proteasome system controls its abundance. However, the role of ubiquitin-specific protease 40 (USP40) in YAP stability remains unclear. Here, USP40 was first identified as a novel regulator of YAP abundance and its target genes in HCC cells. USP40 interacted with YAP to remove the lysine 48 (K48)-linked polyubiquitination of YAP at K252 and K315 sites, thereby maintaining YAP stability. USP40 facilitated the proliferation, colony formation, migration and spheroid formation of HCC cells in vitro and promoted HCC growth in vivo in a YAP-dependent manner. In turn, YAP transcriptionally activated USP40 expression in HCC cells. RNA sequencing analysis showed that about 37% of USP40-regulated genes overlapped with YAP-regulated genes. Interestingly, stiffness-induced USP40 upregulation was abolished by YAP knockdown, and USP40 knockdown attenuated stiffness-induced YAP accumulation in HCC cells. Clinical data demonstrated that USP40 was positively associated with YAP expression in HCC tissues and its high expression indicated a poor prognosis. In conclusion, the USP40/YAP positive feedback loop contributes to HCC progression, suggesting that USP40 may be a promising drug target for anti-HCC.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Proliferación Celular , Retroalimentación , Regulación Neoplásica de la Expresión Génica , Neoplasias Hepáticas/patología , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Proteínas Señalizadoras YAP
10.
ACS Nano ; 18(32): 21411-21432, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39079092

RESUMEN

Epidural adhesion or epidural fibrosis is the major reason for postoperative pain, which remains a clinically challenging problem. Current physical barriers fail to provide a satisfactory therapeutic outcome mainly due to their lack of adhesion, inability to prevent fluid leakage, and exhibiting limited antioxidant properties. Herein, we fabricated a cysteine-modified bioadhesive (SECAgel) with improved sealing and antioxidant properties for epidural adhesion prevention, inspired by the organism's antioxidant systems. The resulting SECAgel showed good injectability and in situ adhesion ability, effectively covering every corner of the irregular wound. Besides, it possessed efficient sealing properties (395.2 mmHg), effectively stopping blood leakage in the rabbit carotid artery transection model. The antioxidant experiments demonstrated that the SECAgel effectively scavenged various radicals and saved the cells from oxidative stress. Two animal models were used to show that the SECAgel effectively inhibited adhesion in both situations with and without cerebrospinal fluid leakage. The RNA sequencing analysis showed that SECAgel treatment effectively inhibited the expression of key genes related to adhesion development, inflammatory response, and oxidative stress. The SECAgel, together with good biocompatibility, can be a good candidate for preventing epidural adhesion in the clinic.


Asunto(s)
Antioxidantes , Animales , Conejos , Antioxidantes/farmacología , Antioxidantes/química , Adherencias Tisulares/prevención & control , Espacio Epidural/patología , Espacio Epidural/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Adhesivos Tisulares/química , Adhesivos Tisulares/farmacología , Cisteína/química , Cisteína/farmacología , Humanos , Ratones , Adhesivos/química , Adhesivos/farmacología , Masculino
11.
Sci Immunol ; 9(98): eadn2717, 2024 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-39178275

RESUMEN

The formation of memory T cells is a fundamental feature of adaptative immunity, allowing the establishment of long-term protection against pathogens. Although emerging evidence suggests that metabolic reprogramming is crucial for memory T cell differentiation and survival, the underlying mechanisms that drive metabolic rewiring in memory T cells remain unclear. Here, we found that up-regulation of the nuclear receptor peroxisome proliferator-activated receptor ß/δ (PPARß/δ) instructs the metabolic reprogramming that occurs during the establishment of central memory CD8+ T cells. PPARß/δ-regulated changes included suppression of aerobic glycolysis and enhancement of oxidative metabolism and fatty acid oxidation. Mechanistically, exposure to interleukin-15 and expression of T cell factor 1 facilitated activation of the PPARß/δ pathway, counteracting apoptosis induced by antigen clearance and metabolic stress. Together, our findings indicate that PPARß/δ is a master metabolic regulator orchestrating a metabolic switch that may be favorable for T cell longevity.


Asunto(s)
Linfocitos T CD8-positivos , Ratones Endogámicos C57BL , PPAR delta , PPAR-beta , Animales , PPAR-beta/metabolismo , PPAR-beta/inmunología , Linfocitos T CD8-positivos/inmunología , PPAR delta/inmunología , PPAR delta/metabolismo , Ratones , Memoria Inmunológica/inmunología , Células T de Memoria/inmunología , Ratones Noqueados , Interleucina-15/inmunología , Interleucina-15/metabolismo , Ratones Transgénicos , Reprogramación Metabólica , Receptores Citoplasmáticos y Nucleares
12.
Biomaterials ; 307: 122537, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38492523

RESUMEN

Non-small cell lung cancer (NSCLC) brain metastases present a significant treatment challenge due to limited drug delivery efficiency and severe adverse reactions. In this study, we address these challenges by designing a "on/off" switchable crosslinked paclitaxel (PTX) nanocarrier, BPM-PD, with novel ultra-pH-sensitive linkages (pH 6.8 to 6.5). BPM-PD demonstrates a distinct "on/off" switchable release of the anti-cancer drug paclitaxel (PTX) in response to the acidic extratumoral microenvironment. The "off" state of BPM-PD@PTX effectively prevents premature drug release in the blood circulation, blood-brain barrier (BBB)/blood-tumor barrier (BTB), and normal brain tissue, surpassing the clinical PTX-nanoformulation (nab-PTX). Meanwhile, the "on" state facilitates precise delivery to NSCLC brain metastases cells. Compared to nab-PTX, BPM-PD@PTX demonstrates improved therapeutic efficacy with a reduced tumor area (only 14.6%) and extended survival duration, while mitigating adverse reactions (over 83.7%) in aspartate aminotransferase (AST) and alanine aminotransferase (ALT), offering a promising approach for the treatment of NSCLC brain metastases. The precise molecular switch also helped to increase the PTX maximum tolerated dose from 25 mg/kg to 45 mg/kg This research contributes to the field of cancer therapeutics and has significant implications for improving the clinical outcomes of NSCLC patients.


Asunto(s)
Antineoplásicos , Neoplasias Encefálicas , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/patología , Neoplasias Pulmonares/tratamiento farmacológico , Paclitaxel/uso terapéutico , Antineoplásicos/uso terapéutico , Neoplasias Encefálicas/tratamiento farmacológico , Microambiente Tumoral
13.
Biochem Biophys Res Commun ; 434(4): 701-4, 2013 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-23624504

RESUMEN

Flavonoid intake is negatively correlated with the incidence of some chronic diseases including cardiovascular diseases, type II diabetes, neurodegenerative diseases, and cancers. Thus, the molecular mechanisms underlying this correlation are of great interest. Although ample attention has been given to the free radical-scavenging potential of flavonoids, the poor bioavailability of exogenous flavonoids suggests that the direct antioxidant activity is unlikely responsible for their favorable effects. This study comprehensively analyzed flavonoid targets. The results show that the main functions of these targets are associated with cancers and cardiovascular and metabolic diseases. Moreover, evolutionary analysis of these targets showed that ~1000 of the targets have homologues in human gut bacterial metagenomes. Clusters of orthologous groups of proteins (COG) analysis indicated that most of these bacterial targets are associated with bacterial metabolism. Given that the metabolism of gut microbiota is coupled with the metabolism of the host, this finding implies that flavonoids exert their benefits by regulating gut microbes. Therefore, the health benefits of flavonoids are well explained by their targets rather than their direct antioxidant potential.


Asunto(s)
Enfermedades Cardiovasculares/prevención & control , Diabetes Mellitus Tipo 2/prevención & control , Flavonoides/administración & dosificación , Metagenoma/efectos de los fármacos , Neoplasias/prevención & control , Enfermedades Cardiovasculares/genética , Diabetes Mellitus Tipo 2/genética , Evolución Molecular , Predisposición Genética a la Enfermedad/genética , Humanos , Metagenoma/genética , Neoplasias/genética , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética
14.
RNA ; 17(8): 1511-28, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21712399

RESUMEN

The biogenesis and function of mature microRNAs (miRNAs) is dependent on the nuclear export of miRNA precursors (pre-miRNA) by Exportin-5 (Exp5). To characterize the molecular mechanisms of how pre-miRNA is recognized and transported by Exp5, we have performed 21 molecular dynamic (MD) simulations of RNA-bound Exp5 (Exp5-RanGTP-premiRNA, Exp5-RanGDP-premiRNA, Exp5-premiRNA), RNA-unbound Exp5 (Exp5-RanGTP, Exp5-RanGDP, apo-Exp5), and pre-miRNA. Our simulations with standard MD, steered molecular dynamics (SMD), and energy analysis have shown that (1) Free Exp5 undergoes extensive opening motion, and in this way facilitates the RanGTP binding. (2) RanGTP efficiently regulates the association/dissociation of pre-miRNA to its complex by inducing conformational changes in the HEAT-repeat helix stacking of Exp5. (3) The GTP hydrolysis prevents Ran from rebinding to Exp5 by regulating the hydrophobic interfaces and salt bridges between Ran and Exp5. (4) The transition from the A'-form to the A-form of the pre-miRNA modulates the structural complementarities between the protein and the pre-miRNA, thus promoting efficient assembly of the complex. (5) The base-flipping process (from the closed to the fully flipped state) of the 2-nt 3' overhang is a prerequisite for the pre-miRNA recognition by Exp5, which occurs in a sequence-independent manner as evidenced by the fact that different 2-nt 3' overhangs bind to Exp5 in essentially the same way. And finally, a plausible mechanism of the pre-miRNA export cycle has been proposed explaining how the protein-protein and protein-RNA interactions are coordinated in physiological conditions.


Asunto(s)
Núcleo Celular/metabolismo , Carioferinas/química , MicroARNs/química , Transporte Activo de Núcleo Celular , Hidrólisis , Carioferinas/metabolismo , Ligandos , MicroARNs/metabolismo , Modelos Moleculares , Conformación de Ácido Nucleico , Unión Proteica , Estructura Terciaria de Proteína
15.
J Cancer Res Clin Oncol ; 149(15): 13591-13605, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37515611

RESUMEN

PURPOSE: This study aimed to assess the actual prognostic significance of different locoregional treatment (LRT) (surgery and radiotherapy) modalities for stage-IV  breast cancer (BC) patients and construct a competing risk nomogram to make precise predictions of the breast cancer-specific death (BCSD) risk among LRT recipients. METHODS: A total of 9279 eligible stage-IV BC patients from the Surveillance Epidemiology and End Results (SEER) database were included in this study. Initially, we evaluated the impact of LRT on survival both before and after the propensity score matching (PSM). Then, we used the Cox hazard proportional model and competing risk model to identify the independent prognostic factors for LRT recipients. Based on the screened variables, a comprehensive nomogram was established. RESULTS: Kaplan-Meier curves demonstrated that LRT significantly prolonged overall survival (OS) and breast cancer-specific survival (BCSS) (P < 0.001). In addition, patients treated with surgery combined with postoperative radiotherapy (PORT) possessed the optimal survival (P < 0.001). Regardless of the surgical modalities, primary tumor resection combined with radiotherapy could ameliorate the prognosis (P < 0.05). Subgroup analysis showed that in patients with T2-T4 stage, PORT had a survival benefit compared with those undergoing surgery combined with preoperative radiotherapy (PRRT) and surgery only. Based on the screened independent prognostic factors, we established a comprehensive nomogram to forecast BCSD in 1 year, 2 years and 3 years, which showed robust predictive ability. CONCLUSION: PORT was associated with a lower BCSD in stage-IV BC patients. The practical nomogram could provide a precise prediction of BCSD for LRT recipients, which was meaningful for patients' individualized management.

16.
Cell Biosci ; 13(1): 62, 2023 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-36944972

RESUMEN

The aim of the present study was to elucidate the evolutionary trajectory of colon cells from normal colon mucosa, to adenoma, then to carcinoma in the same microenvironment. Normal colon, adenoma and carcinoma tissues from the same patient were analyzed by single-cell sequencing, which perfectly simulated the process of time-dependent colon cancer due to the same microenvironment. A total of 22 cell types were identified. Results suggest the presence of dominant clones of same cells including C2 goblet cell, epithelial cell subtype 1 (Epi1), enterocyte cell subset 0 (Entero0), and Entero5 in carcinoma. Epi1 and Entero0 were Co-enriched in antibacterial and IL-17 signaling, Entero5 was enriched in immune response and mucin-type O-glycan biosynthesis. We discovered new colon cancer related genes including AC007952.4, NEK8, CHRM3, ANO7, B3GNT6, NEURL1, ODC1 and KCNMA1. The function of TBC1D4, LTB, C2CD4A, AND GBP4/5 in T cells needs to be clarified. We used colon samples from the same person, which provide new information for colon cancer therapy.

17.
Proteins ; 80(2): 382-97, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22105828

RESUMEN

Transportin 1 (Trn1), as a typical transport receptor of the karyopherin-ß family, mediates numerous RNA binding proteins into the nucleus by recognizing proline-tyrosine nuclear localization signals (PY-NLSs). Such process is regulated by RanGTP through its nucleotide cycle, which is associated with ligand dissociation. Yet a proper description including dynamic properties of Trn1 and its response on ligand/Ran binding has not been accessible so far. Here, we use molecular dynamics simulations to probe the conformational dynamics of the apo-Trn1 and Trn1 in complex with ligand and Ran. The results reveal a strikingly intrinsic flexibility and conformational heterogeneity of Trn1, identified as generally segmental architecture. The segments rotate relative to each other about a flexible hinge and thereby force Trn1 to adopt a conformation compatible with the binding of Ran or substrates. Such binding significantly suppresses the flexibility and conformational heterogeneity of Trn1 and results in a disorder-to-order transition of HR8 loop, which facilitates this loop to allosterically communicate with the C-terminal arch of Trn1. These results give insights into the disassembly and recycling of the Trn1, which has important implications for the regulation of the nuclear transport cycle and for the ligand selectivity.


Asunto(s)
beta Carioferinas/química , beta Carioferinas/metabolismo , Transporte Activo de Núcleo Celular , Enlace de Hidrógeno , Hidrólisis , Simulación de Dinámica Molecular , Señales de Localización Nuclear , Análisis de Componente Principal , Conformación Proteica , Estabilidad Proteica , Proteína de Unión al GTP ran/metabolismo
18.
J Vis Exp ; (180)2022 02 18.
Artículo en Inglés | MEDLINE | ID: mdl-35253791

RESUMEN

Identification of open reading frames (ORFs), especially those encoding small peptides and being actively translated under specific physiological contexts, is critical for comprehensive annotations of context-dependent translatomes. Ribosome profiling, a technique for detecting the binding locations and densities of translating ribosomes on RNA, offers an avenue to rapidly discover where translation is occurring at the genome-wide scale. However, it is not a trivial task in bioinformatics to efficiently and comprehensively identify the translating ORFs for ribosome profiling. Described here is an easy-to-use package, named RiboCode, designed to search for actively translating ORFs of any size from distorted and ambiguous signals in ribosome profiling data. Taking our previously published dataset as an example, this article provides step-by-step instructions for the entire RiboCode pipeline, from preprocessing of the raw data to interpretation of the final output result files. Furthermore, for evaluating the translation rates of the annotated ORFs, procedures for visualization and quantification of ribosome densities on each ORF are also described in detail. In summary, the present article is a useful and timely instruction for the research fields related to translation, small ORFs, and peptides.


Asunto(s)
Biosíntesis de Proteínas , Ribosomas , Biología Computacional/métodos , Sistemas de Lectura Abierta , Ribosomas/genética , Ribosomas/metabolismo , Análisis de Secuencia de ARN/métodos
19.
Front Genet ; 13: 916672, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36051699

RESUMEN

Objective : Our study aims to summarize and analyze the clinical characteristics of transient infantile hypertriglyceridemia (HTGTI) and variants in the glycerol-3-phosphate dehydrogenase 1 (GPD1) gene and the effect of HTGTI on the protein structure of GPD1. Methods: Retrospective analysis, using the general data, symptoms, signs, and auxiliary examinations, was performed on patients with HTGTI, which were confirmed by genetic testing in our hospital and reported cases online. The clinical data were analyzed using statistical and bioinformatic approaches. Results: A total of 31 genetically confirmed HTGTI patients were collected from our hospital and cases reported in the literature. The clinical manifestations showed the median age of onset was 6.0 (1.9, 12.0) months. All the patients had normal psychiatric status, but 22.6% of them presented growth retardation and short stature, 93.5% had hepatomegaly, and 16.1% had splenomegaly. Just a few children were reported with jaundice, cholestasis, and obesity (3.2-6.5%). The laboratory investigations showed that 96.8% of them had hypertriglyceridemia (HTG) with a median level of 3.1 (2.1, 5.5) mmol/L, but only 30.0% had returned to normal during follow-up. In addition, 93.5% of patients had elevated alanine aminotransferase (ALT) with an average level of 92.1 ± 43.5 U/L, while 38.7% had hypercholesterolemia. Upon abdominal imaging, all patients presented fatty liver and liver steatosis, with 66.7% of patients showing hepatic fibrosis. Statistical differences in triglyceride (TG) level were observed in the ≤6 months group compared with the older groups and in the 13 months to 6 years group with >6 years group (H = 22.02, P < 0.05). The restricted cubic spline model showed that severe HTG decreased in the early stage of infants to the normal level; however, it rebounded again to a mild or moderate level after the following days. The genetic test revealed that the main variant types of the GPD1 gene were missense variants (51.6%), followed by splicing variants (35.5%) and nonsense variants (12.9%). Of patients, 87.1% had homozygous variants, with the most frequent loci being c.361-1G > C and c.895G > A. Conclusion: The common manifestations of HTGTI were HTG, hepatomegaly, elevated liver transaminases, and hepatic steatosis in early infancy. However, the recurrence of aberrant HTG may pose long-term detrimental effects on HTGTI patients.

20.
Int J Mol Sci ; 12(2): 1196-221, 2011 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-21541053

RESUMEN

In recent years, great interest has been paid to the development of compounds with high selectivity for central dopamine (DA) D3 receptors, an interesting therapeutic target in the treatment of different neurological disorders. In the present work, based on a dataset of 110 collected benzazepine (BAZ) DA D3 antagonists with diverse kinds of structures, a variety of in silico modeling approaches, including comparative molecular field analysis (CoMFA), comparative similarity indices analysis (CoMSIA), homology modeling, molecular docking and molecular dynamics (MD) were carried out to reveal the requisite 3D structural features for activity. Our results show that both the receptor-based (Q(2) = 0.603, R(2) (ncv) = 0.829, R(2) (pre) = 0.690, SEE = 0.316, SEP = 0.406) and ligand-based 3D-QSAR models (Q(2) = 0.506, R(2) (ncv) =0.838, R(2) (pre) = 0.794, SEE = 0.316, SEP = 0.296) are reliable with proper predictive capacity. In addition, a combined analysis between the CoMFA, CoMSIA contour maps and MD results with a homology DA receptor model shows that: (1) ring-A, position-2 and R(3) substituent in ring-D are crucial in the design of antagonists with higher activity; (2) more bulky R(1) substituents (at position-2 of ring-A) of antagonists may well fit in the binding pocket; (3) hydrophobicity represented by MlogP is important for building satisfactory QSAR models; (4) key amino acids of the binding pocket are CYS101, ILE105, LEU106, VAL151, PHE175, PHE184, PRO254 and ALA251. To our best knowledge, this work is the first report on 3D-QSAR modeling of the new fused BAZs as DA D3 antagonists. These results might provide information for a better understanding of the mechanism of antagonism and thus be helpful in designing new potent DA D3 antagonists.


Asunto(s)
Benzazepinas/química , Relación Estructura-Actividad Cuantitativa , Receptores de Dopamina D3/antagonistas & inhibidores , Secuencia de Aminoácidos , Benzazepinas/farmacología , Simulación del Acoplamiento Molecular , Datos de Secuencia Molecular , Unión Proteica , Receptores de Dopamina D3/química , Receptores de Dopamina D3/metabolismo
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