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1.
Nature ; 604(7907): 763-770, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35418678

RESUMEN

Adhesion G-protein-coupled receptors (aGPCRs) are important for organogenesis, neurodevelopment, reproduction and other processes1-6. Many aGPCRs are activated by a conserved internal (tethered) agonist sequence known as the Stachel sequence7-12. Here, we report the cryogenic electron microscopy (cryo-EM) structures of two aGPCRs in complex with Gs: GPR133 and GPR114. The structures indicate that the Stachel sequences of both receptors assume an α-helical-bulge-ß-sheet structure and insert into a binding site formed by the transmembrane domain (TMD). A hydrophobic interaction motif (HIM) within the Stachel sequence mediates most of the intramolecular interactions with the TMD. Combined with the cryo-EM structures, biochemical characterization of the HIM motif provides insight into the cross-reactivity and selectivity of the Stachel sequences. Two interconnected mechanisms, the sensing of Stachel sequences by the conserved 'toggle switch' W6.53 and the constitution of a hydrogen-bond network formed by Q7.49/Y7.49 and the P6.47/V6.47φφG6.50 motif (φ indicates a hydrophobic residue), are important in Stachel sequence-mediated receptor activation and Gs coupling. Notably, this network stabilizes kink formation in TM helices 6 and 7 (TM6 and TM7, respectively). A common Gs-binding interface is observed between the two aGPCRs, and GPR114 has an extended TM7 that forms unique interactions with Gs. Our structures reveal the detailed mechanisms of aGPCR activation by Stachel sequences and their Gs coupling.


Asunto(s)
Péptidos , Receptores Acoplados a Proteínas G , Sitios de Unión , Microscopía por Crioelectrón , Dominios Proteicos , Estructura Secundaria de Proteína , Receptores Acoplados a Proteínas G/metabolismo , Relación Estructura-Actividad
2.
Proc Natl Acad Sci U S A ; 119(29): e2117054119, 2022 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-35858343

RESUMEN

The G protein-coupled bile acid receptor (GPBAR) is the membrane receptor for bile acids and a driving force of the liver-bile acid-microbiota-organ axis to regulate metabolism and other pathophysiological processes. Although GPBAR is an important therapeutic target for a spectrum of metabolic and neurodegenerative diseases, its activation has also been found to be linked to carcinogenesis, leading to potential side effects. Here, via functional screening, we found that two specific GPBAR agonists, R399 and INT-777, demonstrated strikingly different regulatory effects on the growth and apoptosis of non-small cell lung cancer (NSCLC) cells both in vitro and in vivo. Further mechanistic investigation showed that R399-induced GPBAR activation displayed an obvious bias for ß-arrestin 1 signaling, thus promoting YAP signaling activation to stimulate cell proliferation. Conversely, INT-777 preferentially activated GPBAR-Gs signaling, thus inactivating YAP to inhibit cell proliferation and induce apoptosis. Phosphorylation of GPBAR by GRK2 at S310/S321/S323/S324 sites contributed to R399-induced GPBAR-ß-arrestin 1 association. The cryoelectron microscopy (cryo-EM) structure of the R399-bound GPBAR-Gs complex enabled us to identify key interaction residues and pivotal conformational changes in GPBAR responsible for the arrestin signaling bias and cancer cell proliferation. In summary, we demonstrate that different agonists can regulate distinct functions of cell growth and apoptosis through biased GPBAR signaling and control of YAP activity in a NSCLC cell model. The delineated mechanism and structural basis may facilitate the rational design of GPBAR-targeting drugs with both metabolic and anticancer benefits.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Proteínas de Ciclo Celular , Neoplasias Pulmonares , Receptores Acoplados a Proteínas G , Factores de Transcripción , Ácidos y Sales Biliares/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/patología , Proteínas de Ciclo Celular/metabolismo , Ácidos Cólicos/farmacología , Microscopía por Crioelectrón , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Receptores Acoplados a Proteínas G/agonistas , Receptores Acoplados a Proteínas G/química , Receptores Acoplados a Proteínas G/metabolismo , Factores de Transcripción/metabolismo , beta-Arrestina 1/metabolismo
3.
Proc Natl Acad Sci U S A ; 119(15): e2117004119, 2022 04 12.
Artículo en Inglés | MEDLINE | ID: mdl-35394864

RESUMEN

GPR126 is a member of the adhesion G protein-coupled receptors (aGPCRs) that is essential for the normal development of diverse tissues, and its mutations are implicated in various pathological processes. Here, through screening 34 steroid hormones and their derivatives for cAMP production, we found that progesterone (P4) and 17-hydroxyprogesterone (17OHP) could specifically activate GPR126 and trigger its downstream Gi signaling by binding to the ligand pocket in the seven-transmembrane domain of the C-terminal fragment of GPR126. A detailed mutagenesis screening according to a computational simulated structure model indicated that K1001ECL2 and F1012ECL2 are key residues that specifically recognize 17OHP but not progesterone. Finally, functional analysis revealed that progesterone-triggered GPR126 activation promoted cell growth in vitro and tumorigenesis in vivo, which involved Gi-SRC pathways in a triple-negative breast cancer model. Collectively, our work identified a membrane receptor for progesterone/17OHP and delineated the mechanisms by which GPR126 participated in potential tumor progression in triple-negative breast cancer, which will enrich our understanding of the functions and working mechanisms of both the aGPCR member GPR126 and the steroid hormone progesterone.


Asunto(s)
Progesterona , Receptores Acoplados a Proteínas G , Receptores de Progesterona , Neoplasias de la Mama Triple Negativas , 17-alfa-Hidroxiprogesterona/metabolismo , Línea Celular Tumoral , Humanos , Progesterona/metabolismo , Receptores Acoplados a Proteínas G/química , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Receptores de Progesterona/genética , Receptores de Progesterona/metabolismo , Transducción de Señal , Neoplasias de la Mama Triple Negativas/genética , Neoplasias de la Mama Triple Negativas/metabolismo
4.
Small ; : e2403861, 2024 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-39096062

RESUMEN

Amplifying oxidative stress within tumor cells can effectively inhibit the growth and metastasis of triple-negative breast cancer (TNBC). Therefore, the development of innovative nanomedicines that can effectively disrupt the redox balance represents a promising yet challenging therapeutic strategy for TNBC. In this study, an oxidative stress amplifier, denoted as PBCH, comprising PdAg mesoporous nanozyme and a CaP mineralized layer, loaded with GSH inhibitor L-buthionine sulfoximine (BSO), and further surface-modified with hyaluronic acid that can target CD44, is introduced. In the acidic tumor microenvironment, Ca2+ is initially released, thereby leading to mitochondrial dysfunction and eventually triggering apoptosis. Additionally, BSO suppresses the synthesis of intracellular reduced GSH and further amplifies the level of oxidative stress in cancer cells. Furthermore, PdAg nanozyme can be activated by near-infrared light to induce photothermal and photodynamic effects, causing a burst of ROS and simultaneously promoting cell apoptosis via provoking immunogenic cell death. The high-performance therapeutic effects of PBCH, based on the synergistic effect of aforementioned multiple oxidative damage and photothermal ablation, are validated in TNBC cells and animal models, declaring its potential as a safe and effective anti-tumor agent. The proposed approach offers new perspectives for precise and efficient treatment of TNBC.

5.
Pancreatology ; 24(5): 771-778, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38853072

RESUMEN

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is the digestive malignancy with poor prognosis, and there is still a lack of effective diagnostic biomarkers. OBJECTIVE: We aimed to explore the diagnostic efficiency of DNA methylation in peripheral blood monocytes (PBMCs) in PDAC. METHODS: 850K BeadChips were used to detect genome-wide methylation of PBMCs. For the selected sites, MethylTarget assays was used for further verification. The support vector machine was used to establish the combined panel. RESULTS: A total of 167 PDAC patients and 113 healthy controls were included in this study and were divided into three sets. In the discovery set, we found 4625 differentially methylated positions (DMPs) between cancer group and healthy controls. ZFHX3 (0.16 ± 0.04 vs. 0.18 ± 0.04, P = 0.001), cg01904886 (0.84 ± 0.05 vs. 0.81 ± 0.04, P = 0.02) and NUMBL (0.96 ± 0.005 vs. 0.957 ± 0.005, P = 0.04) were found to be significantly different in training set. The locus with more significant differences, namely ZFHX3, was used for further validation and to establish a combined diagnostic panel with CA19-9. In the validation set, the ROC curve indicated that the AUC value of ZFHX3 was 0.75. The AUC value of the combined model (AUC = 0.92) was higher than that of CA19-9 alone (AUC = 0.88). In patients with normal CA19-9 levels, the ZFHX3 methylation biomarker still maintained good diagnostic efficacy (AUC = 0.71). CONCLUSION: Our study preliminarily suggests that ZFHX3 methylation combined with CA19-9 can improve the detection rate of PDAC. Especially in patients with normal CA19-9, ZFHX3 methylation can maintain stable diagnostic efficacy. The diagnostic value of ZFHX3 methylation still needs to be prospectively validated.


Asunto(s)
Biomarcadores de Tumor , Carcinoma Ductal Pancreático , Metilación de ADN , Monocitos , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/sangre , Biomarcadores de Tumor/sangre , Biomarcadores de Tumor/genética , Masculino , Femenino , Persona de Mediana Edad , Monocitos/metabolismo , Anciano , Carcinoma Ductal Pancreático/diagnóstico , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/sangre , Proteínas de Homeodominio/genética , Estudios de Casos y Controles
6.
Gut ; 72(6): 1129-1142, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-35953094

RESUMEN

OBJECTIVE: The incidence of early-onset colorectal cancer (EO-CRC) is steadily increasing. Here, we aimed to characterise the interactions between gut microbiome, metabolites and microbial enzymes in EO-CRC patients and evaluate their potential as non-invasive biomarkers for EO-CRC. DESIGN: We performed metagenomic and metabolomic analyses, identified multiomics markers and constructed CRC classifiers for the discovery cohort with 130 late-onset CRC (LO-CRC), 114 EO-CRC subjects and age-matched healthy controls (97 LO-Control and 100 EO-Control). An independent cohort of 38 LO-CRC, 24 EO-CRC, 22 LO-Controls and 24 EO-Controls was analysed to validate the results. RESULTS: Compared with controls, reduced alpha-diversity was apparent in both, LO-CRC and EO-CRC subjects. Although common variations existed, integrative analyses identified distinct microbiome-metabolome associations in LO-CRC and EO-CRC. Fusobacterium nucleatum enrichment and short-chain fatty acid depletion, including reduced microbial GABA biosynthesis and a shift in acetate/acetaldehyde metabolism towards acetyl-CoA production characterises LO-CRC. In comparison, multiomics signatures of EO-CRC tended to be associated with enriched Flavonifractor plauti and increased tryptophan, bile acid and choline metabolism. Notably, elevated red meat intake-related species, choline metabolites and KEGG orthology (KO) pldB and cbh gene axis may be potential tumour stimulators in EO-CRC. The predictive model based on metagenomic, metabolomic and KO gene markers achieved a powerful classification performance for distinguishing EO-CRC from controls. CONCLUSION: Our large-sample multiomics data suggest that altered microbiome-metabolome interplay helps explain the pathogenesis of EO-CRC and LO-CRC. The potential of microbiome-derived biomarkers as promising non-invasive tools could be used for the accurate detection and distinction of individuals with EO-CRC.


Asunto(s)
Neoplasias Colorrectales , Microbioma Gastrointestinal , Microbiota , Humanos , Microbioma Gastrointestinal/genética , Neoplasias Colorrectales/diagnóstico , Fenotipo , Colina
7.
Br J Cancer ; 129(3): 426-443, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37380804

RESUMEN

BACKGROUND: The epigenetic mechanisms involved in the progression of pancreatic ductal adenocarcinoma (PDAC) remain largely unexplored. This study aimed to identify key transcription factors (TFs) through multiomics sequencing to investigate the molecular mechanisms of TFs that play critical roles in PDAC. METHODS: To characterise the epigenetic landscape of genetically engineered mouse models (GEMMs) of PDAC with or without KRAS and/or TP53 mutations, we employed ATAC-seq, H3K27ac ChIP-seq, and RNA-seq. The effect of Fos-like antigen 2 (FOSL2) on survival was assessed using the Kaplan-Meier method and multivariate Cox regression analysis for PDAC patients. To study the potential targets of FOSL2, we performed Cleavage Under Targets and Tagmentation (CUT&Tag). To explore the functions and underlying mechanisms of FOSL2 in PDAC progression, we employed several assays, including CCK8, transwell migration and invasion, RT-qPCR, Western blotting analysis, IHC, ChIP-qPCR, dual-luciferase reporter, and xenograft models. RESULTS: Our findings indicated that epigenetic changes played a role in immunosuppressed signalling during PDAC progression. Moreover, we identified FOSL2 as a critical regulator that was up-regulated in PDAC and associated with poor prognosis in patients. FOSL2 promoted cell proliferation, migration, and invasion. Importantly, our research revealed that FOSL2 acted as a downstream target of the KRAS/MAPK pathway and recruited regulatory T (Treg) cells by transcriptionally activating C-C motif chemokine ligand 28 (CCL28). This discovery highlighted the role of an immunosuppressed regulatory axis involving KRAS/MAPK-FOSL2-CCL28-Treg cells in the development of PDAC. CONCLUSION: Our study uncovered that KRAS-driven FOSL2 promoted PDAC progression by transcriptionally activating CCL28, revealing an immunosuppressive role for FOSL2 in PDAC.


Asunto(s)
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Animales , Ratones , Humanos , Proteínas Proto-Oncogénicas p21(ras)/genética , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Regulación hacia Arriba , Cromatina , Ligandos , Carcinoma Ductal Pancreático/patología , Neoplasias Pancreáticas/patología , Proliferación Celular/genética , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica , Quimiocinas CC/metabolismo , Antígeno 2 Relacionado con Fos/genética , Antígeno 2 Relacionado con Fos/metabolismo , Neoplasias Pancreáticas
8.
Small ; 19(20): e2207381, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36799198

RESUMEN

Exosomes are promising new biomarkers for colorectal cancer (CRC) diagnosis, due to their rich biological fingerprints and high level of stability. However, the accurate detection of exosomes with specific surface receptors is limited to clinical application. Herein, an exosome enrichment platform on a 3D porous sponge microfluidic chip is constructed and the exosome capture efficiency of this chip is ≈90%. Also, deep mass spectrometry analysis followed by multi-level expression screenings revealed a CRC-specific exosome membrane protein (SORL1). A method of SORL1 detection by specific quantum dot labeling is further designed and the ensemble classification system is established by extracting features from 64-patched fluorescence images. Importantly, the area under the curve (AUC) using this system is 0.99, which is significantly higher (p < 0.001) than that using a conventional biomarker (carcinoembryonic antigen (CEA), AUC of 0.71). The above system showed similar diagnostic performance, dealing with early-stage CRC, young CRC, and CEA-negative CRC patients.


Asunto(s)
Neoplasias Colorrectales , Exosomas , Humanos , Antígeno Carcinoembrionario , Microfluídica/métodos , Biomarcadores de Tumor/metabolismo , Exosomas/metabolismo , Porosidad , Detección Precoz del Cáncer , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/metabolismo , Proteínas Relacionadas con Receptor de LDL/metabolismo , Proteínas de Transporte de Membrana/metabolismo
9.
Bioconjug Chem ; 33(9): 1698-1706, 2022 09 21.
Artículo en Inglés | MEDLINE | ID: mdl-35960898

RESUMEN

The sensitive detection of cancer-associated exosomal microRNAs shows enormous potential in cancer diagnosis. Herein, a ratiometric fluorescent biosensor based on self-assembled fluorescent gold nanoparticles (Au NPs) and duplex-specific nuclease (DSN)-assisted signal amplification was fabricated for sensitive detection of colorectal cancer (CRC)-associated exosomal miR-92a-3p. In this biosensing system, the hairpin DNA modified with sulfhydryl and fluorescent dye Atto-425 at both ends is conjugated to fluorescent Au NPs through Au-S bonds, resulting in the quenching of Atto-425. The miR-92a-3p can open the hairpin of DNA and forms an miR-92a-3p/DNA heteroduplex, triggering the specific cleavage of DSN for the DNA in the heteroduplex. As a result, Atto-425 leaves the fluorescent Au NPs and recovers the fluorescence emission. The released miR-92a-3p can hybridize with another hairpin DNA and lead to a stronger fluorescence recovery of Atto-425 to form a signal amplification cycle. The stable fluorescence of Au NPs and the changing fluorescence of Atto-425 constitute a ratiometric fluorescent system reflecting the concentration of miR-92a-3p. This biosensor exhibits excellent specificity and can distinguish CRC patients from healthy individuals by detecting miR-92a-3p extracted from clinical exosome samples, showing the potential in CRC diagnosis.


Asunto(s)
Técnicas Biosensibles , Nanopartículas del Metal , MicroARNs , Técnicas Biosensibles/métodos , ADN , Endonucleasas , Colorantes Fluorescentes/química , Oro/química , Humanos , Nanopartículas del Metal/química , MicroARNs/química
10.
Mol Hum Reprod ; 27(8)2021 08 07.
Artículo en Inglés | MEDLINE | ID: mdl-34264302

RESUMEN

Long noncoding RNAs (lncRNAs) have been reported to be involved in various cellular processes and to participate in a variety of human diseases. Recently, increasing studies have reported that lncRNAs are related to many reproductive diseases, such as pathogenesis of recurrent pregnancy loss (RPL), preeclampsia (PE) and gestational diabetes mellitus (GDM). In this study, we aimed to investigate the effect of LINC01088 in trophoblast cells and its potential role in pathogenesis of RPL. LINC01088 was found to be upregulated in first-trimester chorionic villi tissues from RPL patients. Increased LINC01088 repressed proliferation, migration and invasion of trophoblast cells, and promoted apoptosis of trophoblast cells. Further exploration indicated that LINC01088 decreased the production of nitric oxide (NO) by binding and increasing Arginase-1 and decreasing eNOS protein levels. Importantly, JNK and p38 MAPK-signaling pathways were active after overexpression of LINC01088. In conclusion, our studies demonstrated that LINC01088 plays an important role in the pathogenesis of RPL, and is a potential therapeutic target for the treatment of RPL.


Asunto(s)
Aborto Habitual/genética , Sistema de Señalización de MAP Quinasas/fisiología , ARN Largo no Codificante/genética , Trofoblastos/metabolismo , Aborto Habitual/fisiopatología , Adulto , Apoptosis , Arginasa/metabolismo , Sistemas CRISPR-Cas , Ciclo Celular , División Celular , Línea Celular , Movimiento Celular , Vellosidades Coriónicas/metabolismo , Vellosidades Coriónicas/patología , Femenino , Células HEK293 , Humanos , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa de Tipo III/metabolismo , Embarazo , Primer Trimestre del Embarazo , ARN Guía de Kinetoplastida/genética , ARN Largo no Codificante/biosíntesis , Trofoblastos/patología , Regulación hacia Arriba , Adulto Joven
11.
J Cell Mol Med ; 24(19): 11318-11329, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32889785

RESUMEN

Long non-coding RNAs (lncRNAs) have come out as critical molecular regulators of human tumorigenesis. In this study, we sought to identify and functionally characterize lncRNAs as potential mediators of colorectal cancer progression. We screened and identified a novel lncRNA, ADAMTS9-AS1, which was significantly decreased in colorectal cancer tissues and was correlated with clinical outcome of patients according to The Cancer Genome Atlas (TCGA) database. In addition, ADAMTS9-AS1 regulated cell proliferation and migration both in vitro and in vivo. Bioinformatics analysis revealed that overexpression of lncRNA-ADAMTS9-AS1 preferentially affected genes that were linked to proliferation and migration. Mechanistically, we found that ADAMTS9-AS1 obviously suppressed ß-catenin, suggesting that Wnt signalling pathway participates in ADAMTS9-AS1-mediated gene transcriptional regulation in the suppression of colorectal tumorigenesis. Finally, we found that exosomal ADAMTS9-AS1 could serve as a diagnostic biomarker for colorectal cancer with AUC = 0.835 and 95% confidence interval = 0.777-0.911. Our data demonstrated that ADAMTS9-AS1 might play important roles in colorectal cancer by suppressing oncogenesis. Targeting ADAMTS9-AS1 may have potential clinical applications in colorectal cancer prognosis and treatment as an ideal therapeutic target. Finally, exosomal lncRNA-ADAMTS9-AS1 is a promising, novel diagnostic biomarker for colorectal cancer.


Asunto(s)
Biomarcadores de Tumor/genética , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/genética , ARN Largo no Codificante/metabolismo , Vía de Señalización Wnt/genética , Carcinogénesis/genética , Carcinogénesis/patología , Línea Celular Tumoral , Núcleo Celular/metabolismo , Proliferación Celular/genética , Regulación hacia Abajo/genética , Transición Epitelial-Mesenquimal/genética , Exosomas/metabolismo , Exosomas/ultraestructura , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos , Metástasis de la Neoplasia , ARN Largo no Codificante/genética
12.
Mol Cancer ; 19(1): 132, 2020 08 27.
Artículo en Inglés | MEDLINE | ID: mdl-32854710

RESUMEN

At the moment, pancreatic cancer is among the deadliest gastrointestinal diseases, and pancreatic cancer growth is a complex biological process that is based on different kinds of genes. Exosomes are extracellular vesicles containing microRNAs (miRNAs), messenger RNA (mRNA), and proteins, they act as the most prominent mediator of intercellular communication, and they regulate, instruct, and re-educate their surrounding microenvironment and target specific organs. Due to accumulative evidence proved that exosomes are involved in metastasis, cell proliferation, EMT, angiogenesis, and TME of pancreatic cancer, exosomes are crucial potential candidates to detect pancreatic cancer early. This review aims to convey the current understanding of the main functions employed by exosomes in early diagnosis and treatment of pancreatic cancer.


Asunto(s)
Biomarcadores de Tumor/genética , MicroARNs/genética , Neoplasias Pancreáticas/diagnóstico , ARN Mensajero/genética , Proliferación Celular/genética , Exosomas/genética , Vesículas Extracelulares/genética , Regulación Neoplásica de la Expresión Génica/genética , Humanos , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patología , Microambiente Tumoral/genética , Neoplasias Pancreáticas
13.
Mol Cancer ; 19(1): 89, 2020 05 12.
Artículo en Inglés | MEDLINE | ID: mdl-32398152

RESUMEN

An amendment to this paper has been published and can be accessed via the original article.

14.
Hepatology ; 69(4): 1614-1631, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30552782

RESUMEN

Sirtuin 4 (SIRT4) has been reported to play a vital role in the maintenance of glutamine catabolism and adenosine triphosphate (ATP) homeostasis, but its character in hepatocellular carcinomas (HCCs) remains obscure. In this study, we observed low expression of SIRT4 in both HCC cell lines and HCCs from patients. Decreased disease-free survival time is associated with low tumor levels of SIRT4 in patients. Deficiency of SIRT4 facilitated liver tumor development and lung metastasis in xenografts and knockout (KO) mice by promoting colony formation and migration of hepatoma cells and enhancing sphere formation of HCCs. Mechanistically, SIRT4 deletion augmented mammalian target of rapamycin (mTOR) signaling by inactivating adenosine-monophosphate (AMP)-activated protein kinase alpha (AMPKα) through regulation of glutamine catabolism and subsequent AM)/liver kinase B1 (LKB1) axis. Blockage of mTOR by rapamycin or inhibition of glutaminolysis abolished the discrepancy in tumorigenic capacity between SIRT4-depleted hepatoma cells and control cells. Suppression of LKB1 or promotion of AMP by metformin also abrogated the hyperproliferative phenotype caused by SIRT4 loss, which further confirmed that the LKB1/AMPKα/mTOR axis is required in SIRT4-deficiency-promoted HCC tumorigenesis. Conclusion: SIRT4 could exert its tumor suppressive function in HCC by inhibiting glutamine metabolism and thereby increasing the adenosine diphosphate (ADP)/AMP levels to phosphorylate AMPKα by LKB1, which blocks the mTOR signaling pathway.


Asunto(s)
Carcinoma Hepatocelular/etiología , Neoplasias Hepáticas Experimentales/etiología , Proteínas Mitocondriales/metabolismo , Sirtuinas/metabolismo , Proteínas Quinasas Activadas por AMP/metabolismo , Adenosina Monofosfato/metabolismo , Animales , Carcinogénesis , Carcinoma Hepatocelular/enzimología , Regulación hacia Abajo , Glutamina/metabolismo , Células Hep G2 , Humanos , Neoplasias Hepáticas Experimentales/enzimología , Ratones Noqueados , Proteínas Serina-Treonina Quinasas/metabolismo , Transducción de Señal , Sirolimus , Serina-Treonina Quinasas TOR/metabolismo
15.
Pancreatology ; 20(1): 79-88, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31780287

RESUMEN

Pancreatic ductal adenocarcinoma (PDAC) is among the dangerous human cancers, is the 10th highly prevalent cancer, and the fourth sole cause of cancer-related mortality in the United States of America. Notwithstanding the significant commitment, the forecast for people with this burden continues to have a five-year survival rate of just 4-6%. The most critical altered genes within PDAC consist of K-ras the proto-oncogene which is usually mutationally activated above 90% cases and tumor suppressors likeTrp53 are altered at 55%. To face the burden of pancreatic ductal adenocarcinoma, a variety of genetically engineered pancreatic cancer mice models have been created over the last past years. These models have distinctive features and are not all appropriate for preclinical studies. In this review, we focus on differences between two mice models K-rasLSL.G12D/+;Pdx-1-Cre(KC) and K-rasLSL.G12D/+; Trp53R172H/+; Pdx-1-Cre(KPC) in terms of their modeling biology and their clinical relevance.


Asunto(s)
Carcinoma Ductal Pancreático/genética , Modelos Animales de Enfermedad , Neoplasias Pancreáticas/genética , Animales , Predisposición Genética a la Enfermedad , Ratones , Ratones Endogámicos , Mutación , Proto-Oncogenes Mas
16.
J Cell Mol Med ; 23(2): 1396-1405, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30467945

RESUMEN

Exosomes are small membrane vesicles released by many cells. These vesicles can mediate cellular communications by transmitting active molecules including long non-coding RNAs (lncRNAs). In this study, our aim was to identify a panel of lncRNAs in serum exosomes for the diagnosis and recurrence prediction of bladder cancer (BC). The expressions of 11 candidate lncRNAs in exosome were investigated in training set (n = 200) and an independent validation set (n = 320) via quantitative real-time PCR. A three-lncRNA panel (PCAT-1, UBC1 and SNHG16) was finally identified by multivariate logistic regression model to provide high diagnostic accuracy for BC with an area under the receiver-operating characteristic curve (AUC) of 0.857 and 0.826 in training set and validation set, respectively, which was significantly higher than that of urine cytology. The corresponding AUCs of this panel for patients with Ta, T1 and T2-T4 were 0.760, 0.827 and 0.878, respectively. In addition, Kaplan-Meier analysis showed that non-muscle-invasive BC (NMIBC) patients with high UBC1 expression had significantly lower recurrence-free survival (P = 0.01). Multivariate Cox analysis demonstrated that UBC1 was independently associated with tumour recurrence of NMIBC (P = 0.018). Our study suggested that lncRNAs in serum exosomes may serve as considerable diagnostic and prognostic biomarkers of BC.


Asunto(s)
Biomarcadores de Tumor/genética , Exosomas/genética , Recurrencia Local de Neoplasia/diagnóstico , ARN Largo no Codificante/genética , Neoplasias de la Vejiga Urinaria/diagnóstico , Estudios de Casos y Controles , Femenino , Estudios de Seguimiento , Regulación Neoplásica de la Expresión Génica , Humanos , Metástasis Linfática , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/sangre , Recurrencia Local de Neoplasia/genética , Recurrencia Local de Neoplasia/cirugía , Pronóstico , Curva ROC , Neoplasias de la Vejiga Urinaria/sangre , Neoplasias de la Vejiga Urinaria/genética , Neoplasias de la Vejiga Urinaria/cirugía
17.
Mol Cancer ; 18(1): 43, 2019 03 19.
Artículo en Inglés | MEDLINE | ID: mdl-30890168

RESUMEN

BACKGROUND: Oxaliplatin resistance is a major challenge for treatment of advanced colorectal cancer (CRC). Both acquisition of epithelial-mesenchymal transition (EMT) and suppressed drug accumulation in cancer cells contributes to development of oxaliplatin resistance. Aberrant expression of small noncoding RNA, miR-128-3p, has been shown to be a key regulator in tumorigenesis and cancer development. However, its roles in the progression of CRC and oxaliplatin-resistance are largely unknown. METHODS: Oxaliplatin-resistant CRC and normal intestinal FHC cells were transfected with a miR-128-3p expression lentivirus. After transfection, FHC-derived exosomes were isolated and co-cultured with CRC cells. miR-128-3p expression in resistant CRC cells, FHC cells, and exosomes was quantified by quantitative real-time PCR (RT-qPCR). The mRNA and protein levels of miR-128-3p target genes in resistant CRC cells were quantified by RT-qPCR and western blot, respectively. The effects of miR-128-3p on CRC cell viability, apoptosis, EMT, motility and drug efflux were evaluated by CCK8, flow cytometry, Transwell and wound healing assays, immunofluorescence, and atomic absorption spectrophotometry. Xenograft models were used to determine whether miR-128-3p loaded exosomes can re-sensitize CRC cells to oxaliplatin in vivo. RESULTS: In our established stable oxaliplatin-resistant CRC cell lines, in vitro and vivo studies revealed miR-128-3p suppressed EMT and increased intracellular oxaliplatin accumulation. Importantly, our results indicated that lower miR-128-3p expression was associated with poor oxaliplatin response in advanced human CRC patients. Moreover, data showed that miR-128-3p-transfected FHC cells effectively packaged miR-128-3p into secreted exosomes and mediated miR-128-3p delivery to oxaliplatin-resistant cells, improving oxaliplatin response in CRC cells both in vitro and in vivo. In addition, miR-128-3p overexpression up-regulated E-cadherin levels and inhibited oxaliplatin-induced EMT by suppressing Bmi1 expression in resistant cells. Meanwhile, it also decreased oxaliplatin efflux through suppressed expression of the drug transporter MRP5. CONCLUSION: Our results demonstrate that miR-128-3p delivery via exosomes represents a novel strategy enhancing chemosensitivity in CRC through negative regulation of Bmi1 and MRP5. Moreover, miR-128-3p may be a promising diagnostic and prognostic marker for oxaliplatin-based chemotherapy.


Asunto(s)
Neoplasias Colorrectales/tratamiento farmacológico , Resistencia a Antineoplásicos , Transición Epitelial-Mesenquimal , Exosomas/metabolismo , MicroARNs/genética , Oxaliplatino/farmacología , Animales , Antineoplásicos/farmacología , Apoptosis , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Estudios de Casos y Controles , Movimiento Celular , Proliferación Celular , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/patología , Femenino , Estudios de Seguimiento , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Persona de Mediana Edad , Pronóstico , Tasa de Supervivencia , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
18.
Pancreatology ; 19(7): 941-950, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31447281

RESUMEN

Despite advances in therapy and achievements in translational research, pancreatic cancer (PC) remains an invariably fatal malignancy. Risk factors that affect the incidence of PC include diabetes, smoking, obesity, chronic pancreatitis, and diet. The growing worldwide obesity epidemic is associated with an increased risk of the most common cancers, including PC. Chronic inflammation, hormonal effects, circulating adipokines, and adipocyte-mediated inflammatory and immunosuppressive microenvironment are involved in the association of obesity with PC. Herein, we systematically review the epidemiology of PC and the biological mechanisms that may account for this association. Included in this review is a discussion of adipokine-mediated inflammation, lipid metabolism, and the interactions of adipocytes with cancer cells. We consider the influence of bariatric surgery on the risk of PC risk as well as potential molecular targets of therapy. Our review leads us to conclude that targeting adipose tissue to achieve weight loss may represent a new therapeutic strategy for preventing and treating PC.


Asunto(s)
Obesidad/complicaciones , Obesidad/epidemiología , Neoplasias Pancreáticas/complicaciones , Neoplasias Pancreáticas/epidemiología , Regulación de la Expresión Génica , Humanos , Resistencia a la Insulina , Factores de Riesgo , Somatomedinas/genética , Somatomedinas/metabolismo
19.
J Cell Mol Med ; 22(9): 4486-4495, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29993199

RESUMEN

Recent studies have revealed that long non-coding RNAs (lncRNAs) are involved in different physiological processes and human diseases. However, to date, the function and overall clinical significance of the vast majority of lncRNAs in breast cancer remain largely unexplored. Here, we focused on LINC00310 by interrogating the breast invasive carcinoma data set of the Cancer Genome Atlas (TCGA). The results showed that LINC00310 was increased as breast cancer progressed, and the deregulation of LINC00310 was significantly associated with patients' survival. Experiments with knockout (KO) approach by CRISPR/Cas9 system and the subsequent rescue experiments revealed that LINC00310 promoted cell proliferation by regulating c-Myc expression in vitro. Nude mouse xenograft assay demonstrated that LINC00310 KO significantly suppressed tumour growth in vivo. Furthermore, we found that serum LINC00310 expression was significantly up-regulated in patients with breast cancer, and receiver operating characteristic (ROC) curve analysis indicated that LINC00310 had a powerful capability of distinguishing patients with breast cancer from healthy individuals (the area under curve 0.828). Taken together, these results provide a more intuitive approach to explore the clinical relevance and functional roles of lncRNAs. As a result, lncRNAs, such as LINC00310, may be used in clinical applications as circulating markers for breast cancer.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Carcinogénesis/genética , Regulación Neoplásica de la Expresión Génica , Proteínas Proto-Oncogénicas c-myc/genética , ARN Largo no Codificante/genética , Animales , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/genética , Neoplasias de la Mama/mortalidad , Sistemas CRISPR-Cas , Carcinogénesis/metabolismo , Carcinogénesis/patología , Estudios de Casos y Controles , Línea Celular Tumoral , Proliferación Celular , Femenino , Humanos , Ratones , Ratones Desnudos , Oligorribonucleótidos/genética , Oligorribonucleótidos/metabolismo , Pronóstico , Proteínas Proto-Oncogénicas c-myc/metabolismo , ARN Largo no Codificante/antagonistas & inhibidores , ARN Largo no Codificante/metabolismo , Transducción de Señal , Análisis de Supervivencia , Ensayos Antitumor por Modelo de Xenoinjerto
20.
J Cell Mol Med ; 22(5): 2838-2845, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29516641

RESUMEN

Cell-free long non-coding RNAs (lncRNAs) are stably present in urine and can serve as non-invasive biomarkers for cancer. We aimed to identify signatures of lncRNAs in urine for diagnosis and prognosis of bladder cancer (BC). Screening of lncRNAs by microarray analysis was performed using urine samples of 10 BC patients and 10 controls. Expressions of candidate lncRNAs were evaluated in the training and validation set including 230 BC patients and 230 controls by quantitative reverse transcription polymerase chain reaction (qRT-PCR). A two-lncRNA panel (uc004cox.4 and GAS5) was constructed and provided high diagnostic accuracy of BC with an area under the curve (AUC) of 0.885 (95% CI, 0.836-0.924). The AUCs of the lncRNA panel for Ta, T1 and T2-T4 were 0.843, 0.867 and 0.923, respectively, significantly higher than those of urine cytology (all P < .05). Kaplan-Meier analysis revealed that higher level of uc004cox.4 was associated with poor recurrence-free survival (RFS) of non-muscle invasive BC (NMIBC) (P = .008). Additionally, Cox regression analysis indicated that uc004cox.4 was an independent prognostic factor for RFS of NMIBC (P = .018). Taken together, our findings indicated that urinary lncRNA signatures possessed potential clinical value for BC diagnosis. Moreover, uc004cox.4 could provide prognostic information for NMIBC.


Asunto(s)
Biomarcadores de Tumor/orina , Regulación Neoplásica de la Expresión Génica , Recurrencia Local de Neoplasia/genética , ARN Largo no Codificante/genética , ARN Largo no Codificante/orina , Neoplasias de la Vejiga Urinaria/diagnóstico , Neoplasias de la Vejiga Urinaria/genética , Anciano , Biomarcadores de Tumor/genética , Estudios de Casos y Controles , Sistema Libre de Células , Femenino , Humanos , Estimación de Kaplan-Meier , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Modelos de Riesgos Proporcionales , Curva ROC , Reproducibilidad de los Resultados , Neoplasias de la Vejiga Urinaria/orina
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