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1.
Nat Immunol ; 20(2): 183-194, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30643264

RESUMEN

Intestinal stem cells (ISCs) are maintained by stemness signaling for precise modulation of self-renewal and differentiation under homeostasis. However, the way in which intestinal immune cells regulate the self-renewal of ISCs remains elusive. Here we found that mouse and human Lgr5+ ISCs showed high expression of the immune cell-associated circular RNA circPan3 (originating from the Pan3 gene transcript). Deletion of circPan3 in Lgr5+ ISCs impaired their self-renewal capacity and the regeneration of gut epithelium in a manner dependent on immune cells. circPan3 bound mRNA encoding the cytokine IL-13 receptor subunit IL-13Rα1 (Il13ra1) in ISCs to increase its stability, which led to the expression of IL-13Rα1 in ISCs. IL-13 produced by group 2 innate lymphoid cells in the crypt niche engaged IL-13Rα1 on crypt ISCs and activated signaling mediated by IL-13‒IL-13R, which in turn initiated expression of the transcription factor Foxp1. Foxp1 is associated with ß-catenin in rendering its nuclear translocation, which caused activation of the ß-catenin pathway and the maintenance of Lgr5+ ISCs.


Asunto(s)
Autorrenovación de las Células/inmunología , Interleucina-13/metabolismo , Mucosa Intestinal/inmunología , ARN/metabolismo , Células Madre/fisiología , Animales , Proteínas Portadoras/genética , Diferenciación Celular/inmunología , Autorrenovación de las Células/genética , Colitis Ulcerosa/inducido químicamente , Colitis Ulcerosa/inmunología , Sulfato de Dextran/toxicidad , Modelos Animales de Enfermedad , Femenino , Humanos , Interleucina-13/inmunología , Subunidad alfa1 del Receptor de Interleucina-13/genética , Subunidad alfa1 del Receptor de Interleucina-13/inmunología , Subunidad alfa1 del Receptor de Interleucina-13/metabolismo , Mucosa Intestinal/citología , Mucosa Intestinal/metabolismo , Linfocitos/inmunología , Linfocitos/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos ICR , Ratones Noqueados , ARN/genética , ARN/inmunología , ARN Circular , ARN Mensajero/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Regeneración/genética , Regeneración/inmunología , Transducción de Señal/genética , Transducción de Señal/inmunología , beta Catenina/inmunología , beta Catenina/metabolismo
2.
Nature ; 621(7978): 373-380, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37704762

RESUMEN

The development of the human brain involves unique processes (not observed in many other species) that can contribute to neurodevelopmental disorders1-4. Cerebral organoids enable the study of neurodevelopmental disorders in a human context. We have developed the CRISPR-human organoids-single-cell RNA sequencing (CHOOSE) system, which uses verified pairs of guide RNAs, inducible CRISPR-Cas9-based genetic disruption and single-cell transcriptomics for pooled loss-of-function screening in mosaic organoids. Here we show that perturbation of 36 high-risk autism spectrum disorder genes related to transcriptional regulation uncovers their effects on cell fate determination. We find that dorsal intermediate progenitors, ventral progenitors and upper-layer excitatory neurons are among the most vulnerable cell types. We construct a developmental gene regulatory network of cerebral organoids from single-cell transcriptomes and chromatin modalities and identify autism spectrum disorder-associated and perturbation-enriched regulatory modules. Perturbing members of the BRG1/BRM-associated factor (BAF) chromatin remodelling complex leads to enrichment of ventral telencephalon progenitors. Specifically, mutating the BAF subunit ARID1B affects the fate transition of progenitors to oligodendrocyte and interneuron precursor cells, a phenotype that we confirmed in patient-specific induced pluripotent stem cell-derived organoids. Our study paves the way for high-throughput phenotypic characterization of disease susceptibility genes in organoid models with cell state, molecular pathway and gene regulatory network readouts.


Asunto(s)
Trastorno del Espectro Autista , Encéfalo , Discapacidades del Desarrollo , Organoides , Análisis de Expresión Génica de una Sola Célula , Humanos , Trastorno del Espectro Autista/complicaciones , Trastorno del Espectro Autista/genética , Trastorno del Espectro Autista/patología , Trastorno Autístico/complicaciones , Trastorno Autístico/genética , Trastorno Autístico/patología , Encéfalo/citología , Encéfalo/metabolismo , Linaje de la Célula/genética , Cromatina/genética , Proteína 9 Asociada a CRISPR/metabolismo , Sistemas CRISPR-Cas , Discapacidades del Desarrollo/complicaciones , Discapacidades del Desarrollo/genética , Discapacidades del Desarrollo/patología , Edición Génica , Mutación con Pérdida de Función , Mosaicismo , Neuronas/metabolismo , Neuronas/patología , Organoides/citología , Organoides/metabolismo , ARN Guía de Sistemas CRISPR-Cas , Transcripción Genética
3.
Nature ; 621(7978): 355-364, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37612510

RESUMEN

The prevalence of highly repetitive sequences within the human Y chromosome has prevented its complete assembly to date1 and led to its systematic omission from genomic analyses. Here we present de novo assemblies of 43 Y chromosomes spanning 182,900 years of human evolution and report considerable diversity in size and structure. Half of the male-specific euchromatic region is subject to large inversions with a greater than twofold higher recurrence rate compared with all other chromosomes2. Ampliconic sequences associated with these inversions show differing mutation rates that are sequence context dependent, and some ampliconic genes exhibit evidence for concerted evolution with the acquisition and purging of lineage-specific pseudogenes. The largest heterochromatic region in the human genome, Yq12, is composed of alternating repeat arrays that show extensive variation in the number, size and distribution, but retain a 1:1 copy-number ratio. Finally, our data suggest that the boundary between the recombining pseudoautosomal region 1 and the non-recombining portions of the X and Y chromosomes lies 500 kb away from the currently established1 boundary. The availability of fully sequence-resolved Y chromosomes from multiple individuals provides a unique opportunity for identifying new associations of traits with specific Y-chromosomal variants and garnering insights into the evolution and function of complex regions of the human genome.


Asunto(s)
Cromosomas Humanos Y , Evolución Molecular , Humanos , Masculino , Cromosomas Humanos Y/genética , Genoma Humano/genética , Genómica , Tasa de Mutación , Fenotipo , Eucromatina/genética , Seudogenes , Variación Genética/genética , Cromosomas Humanos X/genética , Regiones Pseudoautosómicas/genética
4.
Immunity ; 48(4): 688-701.e7, 2018 04 17.
Artículo en Inglés | MEDLINE | ID: mdl-29625897

RESUMEN

Disrupting the balance between self-renewal and differentiation of hematopoietic stem cells (HSCs) leads to bone marrow failure or hematologic malignancy. However, how HSCs sustain their quiescent state and avoid type I interferon (IFN)-mediated exhaustion remains elusive. Here we defined a circular RNA that we named cia-cGAS that was highly expressed in the nucleus of long-term (LT)-HSCs. Cia-cGAS deficiency in mice caused elevated expression of type I IFNs in bone marrow and led to decreased numbers of dormant LT-HSCs. Under homeostatic conditions, cia-cGAS bound DNA sensor cGAS in the nucleus to block its synthase activity, thereby protecting dormant LT-HSCs from cGAS-mediated exhaustion. Moreover, cia-cGAS harbored a stronger binding affinity to cGAS than self-DNA did and consequently suppressed cGAS-mediated production of type I IFNs in LT-HSCs. Our findings reveal a mechanism by which cia-cGAS inhibits nuclear cGAS by blocking its enzymatic activity and preventing cGAS from recognizing self-DNA to maintain host homeostasis.


Asunto(s)
Diferenciación Celular/fisiología , Células Madre Hematopoyéticas/citología , Interferón Tipo I/metabolismo , Nucleotidiltransferasas/metabolismo , ARN/metabolismo , Animales , Médula Ósea/metabolismo , Comunicación Celular , Línea Celular , Células HEK293 , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Conformación de Ácido Nucleico , Nucleotidiltransferasas/antagonistas & inhibidores , Nucleotidiltransferasas/genética , ARN/genética , Interferencia de ARN , ARN Circular , ARN Interferente Pequeño/genética
5.
Proc Natl Acad Sci U S A ; 120(1): e2203779120, 2023 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-36577075

RESUMEN

Insulin-like growth factor I (IGF-1) is a key regulator of tissue growth and development in response to growth hormone stimulation. In the skeletal system, IGF-1 derived from osteoblasts and chondrocytes are essential for normal bone development; however, whether bone marrow (BM)-resident cells provide distinct sources of IGF-1 in the adult skeleton remains elusive. Here, we show that BM stromal cells (BMSCs) and megakaryocytes/platelets (MKs/PLTs) express the highest levels of IGF-1 in adult long bones. Deletion of Igf1 from BMSCs by Lepr-Cre leads to decreased bone formation, impaired bone regeneration, and increased BM adipogenesis. Importantly, reduction of BMSC-derived IGF-1 contributes to fasting-induced marrow fat accumulation. In contrast, deletion of Igf1 from MKs/PLTs by Pf4-Cre leads to reduced bone formation and regeneration without affecting BM adipogenesis. To our surprise, MKs/PLTs are also an important source of systemic IGF-1. Platelet-rich plasma (PRP) from Pf4-Cre; Igf1f/fmice showed compromised osteogenic potential both in vivo and in vitro, suggesting that MK/PLT-derived IGF-1 underlies the therapeutic effects of PRP. Taken together, this study identifies BMSCs and MKs/PLTs as two important sources of IGF-1 that coordinate to maintain and regenerate the adult skeleton, highlighting reciprocal regulation between the hematopoietic and skeletal systems.


Asunto(s)
Médula Ósea , Factor I del Crecimiento Similar a la Insulina , Ratones , Animales , Factor I del Crecimiento Similar a la Insulina/metabolismo , Diferenciación Celular , Plaquetas/metabolismo , Osteogénesis/genética , Células de la Médula Ósea/metabolismo , Esqueleto
6.
Immunity ; 45(1): 131-44, 2016 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-27421702

RESUMEN

Natural killer (NK) cells and non-cytotoxic interferon-γ (IFN-γ)-producing group I innate lymphoid cells (ILC1s) produce large amounts of IFN-γ and cause activation of innate and adaptive immunity. However, how NKs and ILC1s are primed during infection remains elusive. Here we have shown that a lymphocyte subpopulation natural killer-like B (NKB) cells existed in spleen and mesenteric lymph nodes (MLNs). NKBs had unique features that differed from T and B cells, and produced interleukin-18 (IL-18) and IL-12 at an early phase of infection. NKB cells played a critical role in eradication of microbial infection via secretion of IL-18 and IL-12. Moreover, IL-18 deficiency abrogated the antibacterial effect of NKBs. Upon bacterial challenge, NKB precursors (NKBPs) rapidly differentiated to NKBs that activated NKs and ILC1s against microbial infection. Our findings suggest that NKBs might be exploited to develop effective therapies for treatment of infectious diseases.


Asunto(s)
Linfocitos B/inmunología , Infecciones/inmunología , Células Asesinas Naturales/inmunología , Ganglios Linfáticos/inmunología , Subgrupos Linfocitarios/inmunología , Bazo/inmunología , Animales , Linfocitos B/microbiología , Diferenciación Celular , Células Cultivadas , Humanos , Inmunidad Innata , Infecciones/terapia , Interleucina-12/metabolismo , Interleucina-18/genética , Interleucina-18/metabolismo , Células Asesinas Naturales/microbiología , Activación de Linfocitos , Subgrupos Linfocitarios/microbiología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Células Precursoras de Linfocitos B/inmunología
7.
Mol Ther ; 32(3): 637-645, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38204163

RESUMEN

N-Acetylgalactosamine (GalNAc)-conjugated small interfering RNA (siRNA) therapies have received approval for treating both orphan and prevalent diseases. To improve in vivo efficacy and streamline the chemical synthesis process for efficient and cost-effective manufacturing, we conducted this study to identify better designs of GalNAc-siRNA conjugates for therapeutic development. Here, we present data on redesigned GalNAc-based ligands conjugated with siRNAs against angiopoietin-like 3 (ANGPTL3) and lipoprotein (a) (Lp(a)), two target molecules with the potential to address large unmet medical needs in atherosclerotic cardiovascular diseases. By attaching a novel pyran-derived scaffold to serial monovalent GalNAc units before solid-phase oligonucleotide synthesis, we achieved increased GalNAc-siRNA production efficiency with fewer synthesis steps compared to the standard triantennary GalNAc construct L96. The improved GalNAc-siRNA conjugates demonstrated equivalent or superior in vivo efficacy compared to triantennary GalNAc-conjugated siRNAs.


Asunto(s)
Enfermedades Cardiovasculares , Hepatocitos , Humanos , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/química , Análisis Costo-Beneficio , ARN Bicatenario , Acetilgalactosamina/química , Proteína 3 Similar a la Angiopoyetina
8.
Chem Soc Rev ; 53(7): 3350-3383, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38406832

RESUMEN

Super-resolution imaging has rapidly emerged as an optical microscopy technique, offering advantages of high optical resolution over the past two decades; achieving improved imaging resolution requires significant efforts in developing super-resolution imaging agents characterized by high brightness, high contrast and high sensitivity to fluorescence switching. Apart from technical requirements in optical systems and algorithms, super-resolution imaging relies on fluorescent dyes with special photophysical or photochemical properties. The concept of aggregation-induced emission (AIE) was proposed in 2001, coinciding with unprecedented advancements and innovations in super-resolution imaging technology. AIE probes offer many advantages, including high brightness in the aggregated state, low background signal, a larger Stokes shift, ultra-high photostability, and excellent biocompatibility, making them highly promising for applications in super-resolution imaging. In this review, we summarize the progress in implementation methods and provide insights into the mechanism of AIE-based super-resolution imaging, including fluorescence switching resulting from photochemically-converted aggregation-induced emission, electrostatically controlled aggregation-induced emission and specific binding-regulated aggregation-induced emission. Particularly, the aggregation-induced emission principle has been proposed to achieve spontaneous fluorescence switching, expanding the selection and application scenarios of super-resolution imaging probes. By combining the aggregation-induced emission principle and specific molecular design, we offer some comprehensive insights to facilitate the applications of AIEgens (AIE-active molecules) in super-resolution imaging.

9.
Nano Lett ; 24(14): 4108-4116, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38536003

RESUMEN

Symmetry breaking plays a pivotal role in unlocking intriguing properties and functionalities in material systems. For example, the breaking of spatial and temporal symmetries leads to a fascinating phenomenon: the superconducting diode effect. However, generating and precisely controlling the superconducting diode effect pose significant challenges. Here, we take a novel route with the deliberate manipulation of magnetic charge potentials to realize unconventional superconducting flux-quantum diode effects. We achieve this through suitably tailored nanoengineered arrays of nanobar magnets on top of a superconducting thin film. We demonstrate the vital roles of inversion antisymmetry and its breaking in evoking unconventional superconducting effects, namely a magnetically symmetric diode effect and an odd-parity magnetotransport effect. These effects are nonvolatilely controllable through in situ magnetization switching of the nanobar magnets. Our findings promote the use of antisymmetry (breaking) for initiating unconventional superconducting properties, paving the way for exciting prospects and innovative functionalities in superconducting electronics.

10.
J Cell Mol Med ; 28(12): e18467, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38898581

RESUMEN

TNKS is a new target for the treatment of lung adenocarcinoma, the synergistic effects of the TCM compound Xiaoyan decoction and the TNKS inhibitor E7449 in the intervention on TNKS were investigated, and the possible underlying mechanisms involved were clarified. Immunohistochemistry was used to analyse TNKS expression in tumour tissues. The impact of targeting TNKS on cell growth, invasion, apoptosis, key genes and signalling pathways was investigated in tumour cells by Western blotting, rescue experiments, colony formation assays, flow cytometry and label-free experiments. Tumour xenografts with A549 cells were then transplanted for in vivo study. We found that TNKS high expression was closely related to the advanced tumour stage and tumour size in lung adenocarcinom. After TNKS was knocked down in vitro, the growth, proliferation, migration and invasion were markedly reduced in A549 and H1975 cells. We subsequently applied the Xiaoyan decoction and TNKS inhibitors to intervene in lung adenocarcinoma. Xiaoyan decoction and E7449 suppressed TNKS expression and inhibited adenocarcinoma cell proliferation, migration, invasion and apoptosis in vitro. Proteomic analysis revealed that E7449 treatment may be most closely associated with the classic Wnt/ß-catenin pathway, whereas Xiaoyan decoction treatment may be related to the WNT/PLAN pathway. Xenograft studies confirmed that E7449 or Xiaoyan decoction inhibited lung tumour growth in vivo and attenuated the Wnt signalling pathway in adenocarcinoma. These findings suggest that TNKS is a novel therapeutic target. TCM preparations and small molecule inhibitors are expected to constitute an effective combination strategy.


Asunto(s)
Adenocarcinoma del Pulmón , Apoptosis , Movimiento Celular , Proliferación Celular , Medicamentos Herbarios Chinos , Neoplasias Pulmonares , Ensayos Antitumor por Modelo de Xenoinjerto , Humanos , Animales , Medicamentos Herbarios Chinos/farmacología , Proliferación Celular/efectos de los fármacos , Adenocarcinoma del Pulmón/patología , Adenocarcinoma del Pulmón/genética , Adenocarcinoma del Pulmón/metabolismo , Adenocarcinoma del Pulmón/tratamiento farmacológico , Apoptosis/efectos de los fármacos , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/tratamiento farmacológico , Movimiento Celular/efectos de los fármacos , Vía de Señalización Wnt/efectos de los fármacos , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Ratones , Carcinogénesis/efectos de los fármacos , Carcinogénesis/genética , Carcinogénesis/patología , Células A549 , Ratones Desnudos , Masculino , Femenino , Proteómica/métodos , Ratones Endogámicos BALB C
11.
J Am Chem Soc ; 146(23): 16213-16221, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38814730

RESUMEN

Combining metal-organic frameworks (MOFs) with liquid crystals to construct liquid crystalline MOFs (LCMOF) offers the advantage of endowing and enhancing their functionality, yet it remains a challenging task. Herein, we report chiral liquid crystalline MOF (CLCMOF) thin films by cross-linking the chiral liquid crystals (CLC) with MOF thin films to realize highly circular polarization luminescence (CPL) performance with photo and thermal switching. By layer by layer cross-linking stilbene-containing CLC with stilbene-based MOF (CLC/MOF) thin film, the CLCMOF thin films were successfully obtained after UV irradiation due to the abundant [2 + 2] photocycloaddition. The resulted CLCMOF thin films have strong chirality, obvious photochromic fluorescent, and strong CPL performance (the asymmetry factor reaches to 0.4). Furthermore, due to the photochromic fluorescent MOF and thermotropic CLC, the CPL can be reversed and red-shifted after heating and UV irradiation treatment, showing photo- and thermal CPL switching. Such MOF-based CPL thin films with photo/thermal CPL switching were prepared to patterns and codes for the demonstration of potential application in advanced information anticounterfeit and encryption. This study not only opens a strategy for developing chiral thin films combining MOFs and liquid crystals but also offers a new route to achieve CPL switching in optical applications.

12.
J Am Chem Soc ; 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38848498

RESUMEN

Here we report on the strong magneto-chiral dichroism (MChD) detected through visible and near-infrared light absorption up to 5.0 T on {Er5Ni6} metal clusters obtained by reaction of enantiopure chiral ligands and NiII and ErIII precursors. Single-crystal diffraction analysis reveals that these compounds are 3d-4f heterometallic clusters, showing helical chirality. MChD spectroscopy reveals a high gMChD dissymmetry factor of ca. 0.24 T-1 (T = 4.0 K, B = 1.0 T) for the 4I13/2 ← 4I15/2 magnetic-dipole allowed electronic transition of the ErIII centers. This record value is 1 or 2 orders of magnitude higher than that of the d-d electronic transitions of the NiII ions and the others f-f electric-dipole induced transitions of the ErIII centers. These findings clearly show the key role that magnetic-dipole allowed transitions have in the rational design of chiral lanthanide systems showing strong MChD.

13.
Anal Chem ; 96(18): 7289-7296, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38666489

RESUMEN

Quantitative glycosylation analysis serves as an effective tool for detecting changes in glycosylation patterns in cancer and various diseases. However, compared with N-glycans, O-glycans present challenges in both qualitative and quantitative mass spectrometry analysis due to their low abundance, ease of peeling, lack of a universal enzyme, and difficult accessibility. To address this challenge, we developed O-GlycoIsoQuant, a novel O-glycome quantitative approach utilizing superbase release and isotopic Girard's P labeling. This method facilitates rapid and efficient nonreducing ß-elimination to dissociate O-glycans from proteins using the organic superbase, 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU), combined with light and heavy isotopic Girard's reagent P (GP) labeling for relative quantification of O-glycans by mass spectrometry. Employing this method, labeled O-glycans exhibit a double peak with a mass difference of 5 Da, suitable for stable relative quantification. The O-GlycoIsoQuant method is characterized by its high labeling efficiency, excellent reproducibility (CV < 20%), and good linearity (R2 > 0.99), across a dynamic range spanning a 100-fold range. This method was applied to various complex sample types, including human serum, porcine spermatozoa, human saliva, and urinary extracellular vesicles, detecting 33, 39, 49, and 37 O-glycans, respectively, thereby demonstrating its broad applicability.


Asunto(s)
Glicómica , Marcaje Isotópico , Polisacáridos , Polisacáridos/análisis , Polisacáridos/química , Polisacáridos/metabolismo , Humanos , Glicómica/métodos , Animales , Glicosilación , Masculino , Espectrometría de Masas
14.
Cancer Immunol Immunother ; 73(8): 151, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38832951

RESUMEN

BACKGROUND: Immunotherapy for gastric cancer remains a challenge due to its limited efficacy. Metabolic reprogramming toward glycolysis has emerged as a promising avenue for enhancing the sensitivity of tumors to immunotherapy. Pyruvate dehydrogenase kinases (PDKs) play pivotal roles in regulating glycolysis. The importance of PDKs in the context of gastric cancer immunotherapy and their potential as therapeutic targets have not been fully explored. METHODS: PDK and PD-L1 expression was analyzed using data from the GSE66229 and The Cancer Genome Atlas (TCGA) cohorts. Additionally, the Immune Checkpoint Blockade Therapy Atlas (ICBatlas) database was utilized to assess PDK expression in an immune checkpoint blockade (ICB) therapy group. Subsequently, the upregulation of PD-L1 and the enhancement of anticancer effects achieved by targeting PDK were validated through in vivo and in vitro assays. The impact of PDK on histone acetylation was investigated using ChIP‒qPCR to detect changes in histone acetylation levels. RESULTS: Our analysis revealed a notable negative correlation between PD-L1 and PDK expression. Downregulation of PDK led to a significant increase in PD-L1 expression. PDK inhibition increased histone acetylation levels by promoting acetyl-CoA generation. The augmentation of acetyl-CoA production and concurrent inhibition of histone deacetylation were found to upregulate PD-L1 expression in gastric cancer cells. Additionally, we observed a significant increase in the anticancer effect of PD-L1 antibodies following treatment with a PDK inhibitor. CONCLUSIONS: Downregulation of PDK in gastric cancer cells leads to an increase in PD-L1 expression levels, thus potentially improving the efficacy of PD-L1 immune checkpoint blockade therapy.


Asunto(s)
Antígeno B7-H1 , Glucólisis , Inmunoterapia , Piruvato Deshidrogenasa Quinasa Acetil-Transferidora , Neoplasias Gástricas , Regulación hacia Arriba , Antígeno B7-H1/metabolismo , Humanos , Animales , Piruvato Deshidrogenasa Quinasa Acetil-Transferidora/metabolismo , Piruvato Deshidrogenasa Quinasa Acetil-Transferidora/genética , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/inmunología , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/genética , Inmunoterapia/métodos , Ratones , Inhibidores de Puntos de Control Inmunológico/farmacología , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica , Ensayos Antitumor por Modelo de Xenoinjerto , Ratones Desnudos
15.
BMC Med ; 22(1): 19, 2024 01 09.
Artículo en Inglés | MEDLINE | ID: mdl-38191448

RESUMEN

BACKGROUND: The benefits of first-line, cisplatin-based chemotherapy for muscle-invasive bladder cancer are limited due to intrinsic or acquired resistance to cisplatin. Increasing evidence has revealed the implication of cancer stem cells in the development of chemoresistance. However, the underlying molecular mechanisms remain to be elucidated. This study investigates the role of LASS2, a ceramide synthase, in regulating Wnt/ß-catenin signaling in a subset of stem-like bladder cancer cells and explores strategies to sensitize bladder cancer to cisplatin treatment. METHODS: Data from cohorts of our center and published datasets were used to evaluate the clinical characteristics of LASS2. Flow cytometry was used to sort and analyze bladder cancer stem cells (BCSCs). Tumor sphere formation, soft agar colony formation assay, EdU assay, apoptosis analysis, cell viability, and cisplatin sensitivity assay were used to investigate the functional roles of LASS2. Immunofluorescence, immunoblotting, coimmunoprecipitation, LC-MS, PCR array, luciferase reporter assays, pathway reporter array, chromatin immunoprecipitation, gain-of-function, and loss-of-function approaches were used to investigate the underlying mechanisms. Cell- and patient-derived xenograft models were used to investigate the effect of LASS2 overexpression and a combination of XAV939 on cisplatin sensitization and tumor growth. RESULTS: Patients with low expression of LASS2 have a poorer response to cisplatin-based chemotherapy. Loss of LASS2 confers a stem-like phenotype and contributes to cisplatin resistance. Overexpression of LASS2 results in inhibition of self-renewal ability of BCSCs and increased their sensitivity to cisplatin. Mechanistically, LASS2 inhibits PP2A activity and dissociates PP2A from ß-catenin, preventing the dephosphorylation of ß-catenin and leading to the accumulation of cytosolic phospho-ß-catenin, which decreases the transcription of the downstream genes ABCC2 and CD44 in BCSCs. Overexpression of LASS2 combined with a tankyrase inhibitor (XAV939) synergistically inhibits tumor growth and restores cisplatin sensitivity. CONCLUSIONS: Targeting the LASS2 and ß-catenin pathways may be an effective strategy to overcome cisplatin resistance and inhibit tumor growth in bladder cancer patients.


Asunto(s)
Cisplatino , Esfingosina N-Aciltransferasa , Neoplasias de la Vejiga Urinaria , Humanos , Apoptosis , beta Catenina , Cisplatino/farmacología , Cisplatino/uso terapéutico , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Animales , Esfingosina N-Aciltransferasa/metabolismo
16.
J Vasc Surg ; 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38777158

RESUMEN

OBJECTIVE: Spontaneous carotid artery dissections (sCADs) are the common cause of stroke in middle-aged and young people. There is still a lack of clinical classification to guide the management of sCAD. We reviewed our experience with 179 patients with sCAD and proposed a new classification for sCAD with prognostic and therapeutic significance. METHODS: This is a retrospective review of prospectively collected data from June 2018 to June 2023 of patients with sCAD treated at a large tertiary academic institution in an urban city in China. Based on imaging results, we categorize sCAD into four types: type Ⅰ, intramural hematoma or dissection with <70% luminal narrowing; type Ⅱ, intramural hematoma or dissection with ≥70% luminal narrowing; type Ⅲ, dissecting aneurysm; type ⅣA, extracranial carotid artery occlusion; and type ⅣB, tandem occlusion. We compared the clinical data and prognostic outcomes among various types of sCADs. RESULTS: A total of 179 patients and 197 dissected arteries met the inclusion criteria. The mean age of the 179 patients with sCAD was 49.5 years, 78% were male, and 18 patients (10%) had bilateral sCAD. According to our classification, there were 56 type Ⅰ (28.4%), 50 type Ⅱ (25.4%), 60 type Ⅲ (30.5%), and 31 type Ⅳ (15.7%) dissections. During a mean hospitalization length of 11.4 ± 47.0 days, there were nine recurrent strokes (4.6%) after medical treatment, two type Ⅲ dissections (1.0%), seven type Ⅳ dissections (3.6%), all ipsilateral, and one death. Overall, there were seven (3.6%, 1 type Ⅰ dissection, 3 type Ⅱ dissections, 2 type Ⅲ dissections, and 1 type Ⅳ dissection) recurrent strokes and three (1.5%, all type Ⅲ dissections) recurrent transient ischemic attacks in patients treated with just medical therapy during the follow-up period, all ipsilateral, with a mean follow-up of 26 months (range, 3-59 months). These patients did not undergo further intervention due to the high difficulty associated with endovascular treatment (EVT) or the mild nature of recurrent cerebral ischemic symptoms. Twenty-nine type I dissections (51.8%) were completely recanalized after antithrombotic therapy. A total of 19 type II dissections (38%) and 44 type III dissections (73%) received EVT for persistent flow-limited dissections, enlargement of dissecting aneurysms, or aggravation of neurological symptoms despite antithrombotic therapy. Type Ⅳ dissections are more likely to lead to the occurrence of ischemic stroke and presented with more severe symptoms. Eight type IVB dissections (33%) received acute phase intervention due to distal thromboembolism or aggravation of neurological symptoms after medical treatment. In terms of cerebral ischemic events and mortality, there were no statistically significant differences among the four types of sCAD (all P > .05). Favorable outcome was achieved in 168 patients (93.9%). CONCLUSIONS: This study proposed a novel and more comprehensive classification method and the modern management strategy for sCAD. Antithrombotic therapy is beneficial to reduce the risk of recurrent stroke for stable sCAD. Non-emergent EVT can be an alternative therapeutic approach for patients who meet indications as in type II to IVA dissections. Urgent procedure with neurovascular intervention is necessary for some type IVB dissections. The short-term results of EVT for sCAD are encouraging, and long-term device-related and functional outcomes should undergo further research.

17.
J Vasc Surg ; 79(1): 3-10, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37734569

RESUMEN

OBJECTIVE: Complex endovascular juxta-, para- and suprarenal abdominal aortic aneurysm repair (comEVAR) is frequently accomplished with commercially available fenestrated (FEVAR) devices or off-label use of aortoiliac devices with parallel branch stents (chEVAR). We sought to evaluate the implantable vascular device costs incurred with these procedures as compared with standard Medicare reimbursement to determine the financial viability of comEVAR in the modern era. METHODS: Five geographically distinct institutions with high-volume, complex aortic centers were included. Implantable aortoiliac and branch stent device cost data from 25 consecutive, recent, comEVAR in the treatment of juxta-, para-, and suprarenal aortic aneurysms at each center were analyzed. Cases of rupture, thoracic aneurysms, reinterventions, and physician-modified EVAR were excluded, as were ancillary costs from nonimplantable equipment. Data from all institutions were combined and stratified into an overall cost group and two, individual cost groups: FEVAR or chEVAR. These groups were compared, and each respective group was then compared with weighted Medicare reimbursement for Diagnosis-Related Group codes 268/269. Median device costs were obtained from an independent purchasing consortium of >3000 medical centers, yielding true median cost-to-institution data rather than speculative, administrative projections or estimates. RESULTS: A total of 125 cases were analyzed: 70 FEVAR and 53 chEVAR. Two cases of combined FEVAR/chEVAR were included in total cost analysis, but excluded from direct FEVAR vs chEVAR comparison. Median Medicare reimbursement was calculated as $35,755 per case. Combined average implantable device cost for all analyzed cases was $28,470 per case, or 80% of the median reimbursement ($28,470/$35,755). Average FEVAR device cost per case ($26,499) was significantly lower than average chEVAR cost per case ($32,122; P < .002). Device cost was 74% ($26,499/$35,755) of total reimbursement for FEVAR and 90% ($32,122/$35,755) for chEVAR. CONCLUSIONS: Results from this multi-institutional analysis show that implantable device cost alone represents the vast majority of weighted total Medicare reimbursement per case with comEVAR, and that chEVAR is significantly more costly than FEVAR. Inadequate Medicare reimbursement for these cases puts high-volume, high-complexity aortic centers at a distinct financial disadvantage. In the interest of optimizing patient care, these data suggest a reconsideration of previously established, outdated, Diagnosis-Related Group coding and Medicare reimbursement for comEVAR.


Asunto(s)
Aneurisma de la Aorta Abdominal , Implantación de Prótesis Vascular , Procedimientos Endovasculares , Anciano , Humanos , Estados Unidos , Reparación Endovascular de Aneurismas , Prótesis Vascular , Aneurisma de la Aorta Abdominal/cirugía , Factores de Riesgo , Resultado del Tratamiento , Medicare , Stents , Costos de Hospital , Estudios Retrospectivos , Diseño de Prótesis
18.
Osteoporos Int ; 35(1): 53-67, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37698600

RESUMEN

We examined the performance of an intelligent fracture liaison service (FLS) assisted by digital health (DH) to reduce all-cause mortality (ACM) risk. According to our findings, the new FLS reduced ACM by 36%. INTRODUCTION: A well-designed secondary prevention program known as FLS enhances the bone densitometry-based assessment rate as well as osteoporosis (OP) medication usage following a fracture. However, there are only a few reports on FLS incorporating DH, and it remains unclear whether this integration has influenced patient ACM, which refers to the overall death rate from any cause during the study period. METHODS: This retrospective observational study was conducted on data from the Fragility Fracture Registration System database linked to the Regional Health Registration Platform of Kunshan City and the Population Death Registration System of Jiangsu Province for one tertiary-level A hospital in China. Patients aged ≥ 50 years, who experienced an OP fracture between January 1, 2017, and July 27, 2022, requiring hospitalization, were selected for analysis. We compared the outcomes of patients who received routine fragility fracture management (the no-FLS group) or FLS (the FLS group). We employed multivariable Cox regression with inverse probability weighting based on the propensity score (PS). RESULTS: Of 2317 patients, 756 (32.6%) received FLS and 1561 (67.4%) did not. Using PS matching, we minimized the baseline characteristic differences between the two groups in the propensity score-matched samples, relative to the unmatched samples. Based on our analysis, the new FLS reduced ACM by 36% (hazard ratio [HR], 0.64; 95% confidence interval [CI], 0.47 to 0.87; P-value = 0.004). Moreover, FLS patients experienced further reductions in fall-related mortality, refracture rate, and total refracture-related hospital costs, and had increased dual-energy X-ray absorptiometry (DXA) testing and treatment initiation rates, relative to the no-FLS patients. CONCLUSIONS: A new FLS model implementation assisted by DH can effectively reduce ACM among elderly patients with OP fractures requiring surgery. In future investigations, we recommend examining the scalability of this model.


Asunto(s)
Conservadores de la Densidad Ósea , Osteoporosis , Fracturas Osteoporóticas , Anciano , Humanos , Fracturas Osteoporóticas/epidemiología , Salud Digital , Conservadores de la Densidad Ósea/uso terapéutico , Osteoporosis/tratamiento farmacológico , Osteoporosis/epidemiología , Absorciometría de Fotón , Prevención Secundaria
19.
Osteoporos Int ; 35(7): 1249-1259, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38771526

RESUMEN

This large-scale prospective study showed that a significant association between longer duration of daily outdoor walking and reduced osteoporosis risk was found among older adults, particularly among those with a low genetic predisposition to osteoporosis, which highlighted the importance of outdoor walking as a simple, cost-effective adjunct for preventing osteoporosis. PURPOSE: The available cross-sectional data and small-scale studies indicate that outdoor walking benefits bone metabolism. Nevertheless, there is a scarcity of comprehensive prospective research investigating the enduring correlation between outdoor walking and osteoporosis. This study aims to conduct a prospective analysis of the correlation between outdoor walking and osteoporosis while also examining potential variations influenced by genetic susceptibility to osteoporosis. METHODS: 24,700 older adults without osteoporosis at baseline were enrolled. These individuals were followed up until December 31, 2021, during which data on outdoor walking was gathered. The genetic risk score for osteoporosis was comprised of 14 single-nucleotide polymorphisms. RESULTS: 4,586 cases of osteoporosis were identified throughout a median follow-up period of 37.3 months. Those who walked outside for > 30 but ≤ 60 min per day had a hazard ratio (HR) of 0.83 (95% confidence interval (CI): 0.72-0.95) for incident osteoporosis, whereas those who walked outside for > 60 min per day had an HR of 0.60 (95% CI: 0.39-0.92). We found that osteoporosis risk exhibited a declining trend in individuals with low genetic risk. Individuals walking outside for > 60 min per day tended to have the lowest overall osteoporosis risk among those with high genetic risk. CONCLUSIONS: A significant negative correlation exists between an extended period of daily outdoor walking and osteoporosis incidence risk. This correlation is particularly pronounced among individuals with low genetic risk. The results above underscore the significance of outdoor walking as a simple and economical adjunct to public health programs to prevent osteoporosis.


Asunto(s)
Predisposición Genética a la Enfermedad , Osteoporosis , Polimorfismo de Nucleótido Simple , Caminata , Humanos , Femenino , Anciano , Masculino , Caminata/fisiología , Estudios Prospectivos , Osteoporosis/genética , Osteoporosis/epidemiología , Incidencia , Persona de Mediana Edad , Factores de Riesgo , Medición de Riesgo/métodos , Anciano de 80 o más Años , Densidad Ósea/genética , Densidad Ósea/fisiología
20.
Osteoporos Int ; 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38844560

RESUMEN

We conducted a retrospective cohort analysis to examine the association between hemoglobin (Hb) levels and refracture risk in elderly patients with osteoporotic fractures (OPFs). Our findings suggest a nonlinear relationship exists in females, and females with Hb levels below 10.7 g/dL may be at a higher risk of refracture. INTRODUCTION: Hematopoiesis and bone health have a reciprocal influence on each other. Nevertheless, there is a scarcity of in-depth research on the association between Hb levels and the occurrence of fractures. The present research aimed to investigate the correlation between Hb levels and the rate of refracture within 5 years among individuals with OPFs. METHODS: A retrospective cohort analysis was undertaken between 2017 and 2022. The study included 1906 individuals who were inhabitants of Kunshan and were over 60 years old. These individuals had experienced an OPF between January 1, 2017, and July 27, 2022, resulting in their hospitalization. Cox proportional hazard regression models were used to evaluate the risk of refracture within 5 years based on the Hb levels acquired during the admission examination, with consideration for sex differences. A nonlinear relationship was identified using smoothed curve fitting and threshold analysis. Kaplan-Meier curves were used to compare refracture rates between patients with low and high Hb levels. RESULTS: Elderly female patients with OPFs and lower Hb levels exhibited a significantly higher risk of a 5-year refracture. Conversely, no significant associations were observed between the two variables in male patients. A nonlinear correlation was found between Hb levels and the probability of refracture in females, with a turning point identified at 10.7 g/dL of Hb levels. A strong negative association was observed with the five-year refracture rate when Hb levels fell below 10.7 g/dL (hazard ratio (HR) = 0.63; 95% confidence interval (CI) 0.48 to 0.83; P-value = 0.0008). This finding suggests that for every 1 g/dL increase in Hb below 10.7 g/dL, the risk of refracture reduced by 37%. However, no statistically significant association was observed when Hb levels were above 10.7 g/dL. CONCLUSIONS: The findings demonstrated a significant negative correlation between Hb levels and the likelihood of refracture in elderly female patients with OPFs and suggested that elderly females with recent OPFs and Hb levels below 10.7 g/dL may be at a higher risk of refracture. Additionally, the Hb levels can serve as an indicator of bone fragility in elderly female patients with OPFs. These findings highlight the importance of monitoring Hb levels as a part of comprehensive management strategies to both assess skeletal health and prevent refractures in this population.

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