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1.
Mol Cell ; 76(3): 359-370, 2019 11 07.
Artículo en Inglés | MEDLINE | ID: mdl-31668929

RESUMEN

The engagement of programmed cell death protein 1 (PD-1; encoded by the PDCD1 gene) receptor expressed on activated T cells and its ligand, programmed death-ligand 1 (PD-L1; encoded by the CD274 gene), is a major co-inhibitory checkpoint signaling that controls T cell activities. Various types of cancers express high levels of PD-L1 and exploit PD-L1/PD-1 signaling to evade T cell immunity. Blocking the PD-L1/PD-1 pathway has consistently shown remarkable anti-tumor effects in patients with advanced cancers and is recognized as the gold standard for developing new immune checkpoint blockade (ICB) and combination therapies. However, the response rates of anti-PD-L1 have been limited in several solid tumors. Therefore, furthering our understanding of the regulatory mechanisms of PD-L1 can bring substantial benefits to patients with cancer by improving the efficacy of current PD-L1/PD-1 blockade or other ICBs. In this review, we provide current knowledge of PD-L1 regulatory mechanisms at the transcriptional, posttranscriptional, post-translational, and extracellular levels, and discuss the implications of these findings in cancer diagnosis and immunotherapy.


Asunto(s)
Antígeno B7-H1/metabolismo , Biomarcadores de Tumor/metabolismo , Neoplasias/metabolismo , Animales , Antineoplásicos Inmunológicos/uso terapéutico , Antígeno B7-H1/antagonistas & inhibidores , Antígeno B7-H1/genética , Antígeno B7-H1/inmunología , Biomarcadores de Tumor/antagonistas & inhibidores , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/inmunología , Regulación Neoplásica de la Expresión Génica , Humanos , Terapia Molecular Dirigida , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Neoplasias/inmunología , Procesamiento Proteico-Postraduccional , Procesamiento Postranscripcional del ARN , Transducción de Señal , Transcripción Genética , Escape del Tumor
2.
Mol Cell ; 71(4): 606-620.e7, 2018 08 16.
Artículo en Inglés | MEDLINE | ID: mdl-30118680

RESUMEN

Metformin has been reported to possess antitumor activity and maintain high cytotoxic T lymphocyte (CTL) immune surveillance. However, the functions and detailed mechanisms of metformin's role in cancer immunity are not fully understood. Here, we show that metformin increases CTL activity by reducing the stability and membrane localization of programmed death ligand-1 (PD-L1). Furthermore, we discover that AMP-activated protein kinase (AMPK) activated by metformin directly phosphorylates S195 of PD-L1. S195 phosphorylation induces abnormal PD-L1 glycosylation, resulting in its ER accumulation and ER-associated protein degradation (ERAD). Consistently, tumor tissues from metformin-treated breast cancer patients exhibit reduced PD-L1 levels with AMPK activation. Blocking the inhibitory signal of PD-L1 by metformin enhances CTL activity against cancer cells. Our findings identify a new regulatory mechanism of PD-L1 expression through the ERAD pathway and suggest that the metformin-CTLA4 blockade combination has the potential to increase the efficacy of immunotherapy.


Asunto(s)
Antineoplásicos/farmacología , Antígeno B7-H1/genética , Antígeno CTLA-4/genética , Regulación Neoplásica de la Expresión Génica , Hipoglucemiantes/farmacología , Metformina/farmacología , Proteínas Quinasas Activadas por AMP/genética , Proteínas Quinasas Activadas por AMP/inmunología , Animales , Antígeno B7-H1/inmunología , Antígeno CTLA-4/inmunología , Línea Celular Tumoral , Retículo Endoplásmico/efectos de los fármacos , Retículo Endoplásmico/genética , Retículo Endoplásmico/metabolismo , Degradación Asociada con el Retículo Endoplásmico , Células Epiteliales/citología , Células Epiteliales/efectos de los fármacos , Células Epiteliales/inmunología , Femenino , Glicosilación , Humanos , Glándulas Mamarias Humanas/citología , Glándulas Mamarias Humanas/efectos de los fármacos , Glándulas Mamarias Humanas/inmunología , Melanoma Experimental/tratamiento farmacológico , Melanoma Experimental/genética , Melanoma Experimental/inmunología , Melanoma Experimental/patología , Ratones , Ratones Endogámicos NOD , Fosforilación , Serina/metabolismo , Linfocitos T Citotóxicos/citología , Linfocitos T Citotóxicos/efectos de los fármacos , Linfocitos T Citotóxicos/inmunología
3.
Neuroimage ; 289: 120535, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38342188

RESUMEN

Neurovascular coupling serves as an essential neurophysiological mechanism in functional neuroimaging, which is generally presumed to be robust and invariant across different physiological states, encompassing both task engagement and resting state. Nevertheless, emerging evidence suggests that neurovascular coupling may exhibit state dependency, even in normal human participants. To investigate this premise, we analyzed the cross-frequency spectral correspondence between concurrently recorded electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) data, utilizing them as proxies for neurovascular coupling during the two conditions: an eye-open-eye-close (EOEC) task and a resting state. We hypothesized that given the state dependency of neurovascular coupling, EEG-fMRI spectral correspondences would change between the two conditions in the visual system. During the EOEC task, we observed a negative phase-amplitude-coupling (PAC) between EEG alpha-band and fMRI visual activity. Conversely, in the resting state, a pronounced amplitude-amplitude-coupling (AAC) emerged between EEG and fMRI signals, as evidenced by the spectral correspondence between the EEG gamma-band of the midline occipital channel (Oz) and the high-frequency fMRI signals (0.15-0.25 Hz) in the visual network. This study reveals distinct scenarios of EEG-fMRI spectral correspondence in healthy participants, corroborating the state-dependent nature of neurovascular coupling.


Asunto(s)
Imagen por Resonancia Magnética , Acoplamiento Neurovascular , Humanos , Imagen por Resonancia Magnética/métodos , Acoplamiento Neurovascular/fisiología , Mapeo Encefálico/métodos , Electroencefalografía/métodos , Ojo , Encéfalo/diagnóstico por imagen , Encéfalo/fisiología
4.
PLoS Pathog ; 17(8): e1009758, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34379705

RESUMEN

Since the pandemic of COVID-19 has intensely struck human society, small animal model for this infectious disease is in urgent need for basic and pharmaceutical research. Although several COVID-19 animal models have been identified, many of them show either minimal or inadequate pathophysiology after SARS-CoV-2 challenge. Here, we describe a new and versatile strategy to rapidly establish a mouse model for emerging infectious diseases in one month by multi-route, multi-serotype transduction with recombinant adeno-associated virus (AAV) vectors expressing viral receptor. In this study, the proposed approach enables profound and enduring systemic expression of SARS-CoV-2-receptor hACE2 in wild-type mice and renders them vulnerable to SARS-CoV-2 infection. Upon virus challenge, generated AAV/hACE2 mice showed pathophysiology closely mimicking the patients with severe COVID-19. The efficacy of a novel therapeutic antibody cocktail RBD-chAbs for COVID-19 was tested and confirmed by using this AAV/hACE2 mouse model, further demonstrating its successful application in drug development.


Asunto(s)
COVID-19 , Enfermedades Transmisibles Emergentes , Modelos Animales de Enfermedad , Células 3T3 , Enzima Convertidora de Angiotensina 2/genética , Animales , Anticuerpos Antivirales/inmunología , Anticuerpos Antivirales/uso terapéutico , COVID-19/inmunología , COVID-19/patología , COVID-19/fisiopatología , Chlorocebus aethiops , Dependovirus/genética , Humanos , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Transducción Genética , Células Vero
5.
J Med Virol ; 95(2): e28478, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36609964

RESUMEN

Patients with severe COVID-19 often suffer from lymphopenia, which is linked to T-cell sequestration, cytokine storm, and mortality. However, it remains largely unknown how severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) induces lymphopenia. Here, we studied the transcriptomic profile and epigenomic alterations involved in cytokine production by SARS-CoV-2-infected cells. We adopted a reverse time-order gene coexpression network approach to analyze time-series RNA-sequencing data, revealing epigenetic modifications at the late stage of viral egress. Furthermore, we identified SARS-CoV-2-activated nuclear factor-κB (NF-κB) and interferon regulatory factor 1 (IRF1) pathways contributing to viral infection and COVID-19 severity through epigenetic analysis of H3K4me3 chromatin immunoprecipitation sequencing. Cross-referencing our transcriptomic and epigenomic data sets revealed that coupling NF-κB and IRF1 pathways mediate programmed death ligand-1 (PD-L1) immunosuppressive programs. Interestingly, we observed higher PD-L1 expression in Omicron-infected cells than SARS-CoV-2 infected cells. Blocking PD-L1 at an early stage of virally-infected AAV-hACE2 mice significantly recovered lymphocyte counts and lowered inflammatory cytokine levels. Our findings indicate that targeting the SARS-CoV-2-mediated NF-κB and IRF1-PD-L1 axis may represent an alternative strategy to reduce COVID-19 severity.


Asunto(s)
COVID-19 , Linfopenia , Animales , Ratones , SARS-CoV-2/metabolismo , Antígeno B7-H1 , Evasión Inmune , FN-kappa B/metabolismo , Regulación hacia Arriba , Citocinas/metabolismo
6.
Brain Cogn ; 169: 105987, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37126951

RESUMEN

The major and minor modes in Western music have positive and negative connotations, respectively. The present fMRI study examined listeners' neural responses to switches between major and minor modes. We manipulated the final chords of J. S. Bach's keyboard pieces so that each major-mode passage ended with either the major (Major-Major) or minor (Major-Minor) tonic chord, and each minor-mode passage ended with either the minor (Minor-Minor) or major (Minor-Major) tonic chord. If the final major and minor chords have positive and negative reward values respectively, the Major-Minor and Minor-Major stimuli would cause negative and positive reward prediction errors (RPEs) respectively in a listener's brain. We found that activity in a frontoparietal network was significantly higher for Major-Minor than for Major-Major. Based on previous research, these results support the idea that a major-to-minor switch causes negative RPE. The contrast of Minor-Major minus Minor-Minor yielded activation in the ventral insula and visual cortex, speaking against the idea that a minor-to-major switch causes positive RPE. We discuss our results in relation to executive functions and the emotional connotations of major versus minor modes.


Asunto(s)
Imagen por Resonancia Magnética , Música , Humanos , Imagen por Resonancia Magnética/métodos , Música/psicología , Encéfalo/diagnóstico por imagen , Encéfalo/fisiología , Emociones , Procesos Mentales , Percepción Auditiva/fisiología
7.
J Xray Sci Technol ; 31(3): 453-461, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36806539

RESUMEN

PURPOSE: This study aims to introduce a novel low-dose abdominal computed tomography (CT) protocol adapted with model-based iterative reconstruction (MBIR), To validate the adaptability of this protocol, objective image quality and subjective clinical scores of low-dose MBIR images are compared with the normal-dose images. METHODS: Normal-dose abdominal CT images of 58 patients and low-dose abdominal CT images of 52 patients are reconstructed using both conventional filtered back projection (FBP) and MBIR methods with and without smooth applying. Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) are used to compare image quality between the normal-dose and low-dose CT scans. CT dose indices (CTDI) of normal-dose and low-dose abdominal CT images on post-contrast venous phase are also compared. RESULTS: The SNR, CNR and clinical score of low-dose MBIR images all show significant higher values (Bonferroni p < 0.05) than those of normal-dose images with conventional FBP method. A total of around 40% radiation dose reduction (CTDI: 5.3 vs 8.7 mGy) could be achieved via our novel abdominal CT protocol. CONCLUSIONS: With the higher SNR/CNR and clinical scores, the low-dose CT abdominal imaging protocol with MBIR could effectively reduce the radiation for patients and provide equal or even higher image quality and also its adaptability in clinical abdominal CT image diagnosis.


Asunto(s)
Abdomen , Tomografía Computarizada por Rayos X , Humanos , Dosis de Radiación , Tomografía Computarizada por Rayos X/métodos , Abdomen/diagnóstico por imagen , Relación Señal-Ruido , Cintigrafía , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Algoritmos
8.
Gerontol Geriatr Educ ; 44(1): 102-117, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-34549668

RESUMEN

This study explored the preferences of different stakeholders when translating geriatrics and gerontology concepts into children's picture books, with the aim of developing a feasible model. Following the stakeholder engagement design and qualitative method, three types of stakeholders were enrolled: medical and educational professionals (n = 9), older adults aged over 65 (n = 9), and children aged 9 to 12 (n = 7). Individual interviews and focus groups were used to collect the views of the stakeholders as a basis for revising the picture book, as well as to analyze the opinions of different stakeholders. Results show that medical professionals' recommendations focused on intellectual content (18.0%) and written verbal narratives (16.5%). Education experts tended to recommend textual verbal narratives (18.8%) and storyline (6.0%). Older adults's suggestions focused on story content (6.8%) and included detailed descriptions of older adults. Children's suggestions were focused on plot arrangement (2.3%) and text size (2.3%). Mean scores for the appropriateness of the three picture book materials increased after the stakeholder engagement, with the communication literacy picture book achieved statistical significance (p = .042). It is concluded that the stakeholder engagement design is a viable development model for achieving intergenerational understanding, realistic and theoretical goals, and bridging heterogeneity across the stakeholders.


Asunto(s)
Geriatría , Humanos , Anciano , Geriatría/educación , Participación de los Interesados , Grupos Focales , Libros , Narración
9.
J Hepatol ; 74(4): 907-918, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33031845

RESUMEN

BACKGROUND & AIMS: There are currently limited therapeutic options for hepatocellular carcinoma (HCC), particularly when it is diagnosed at advanced stages. Herein, we examined the pathophysiological role of ROS1 and assessed the utility of ROS1-targeted therapy for the treatment of HCC. METHODS: Recombinant ribonucleases (RNases) were purified, and the ligand-receptor relationship between RNase7 and ROS1 was validated in HCC cell lines by Duolink, immunofluorescence, and immunoprecipitation assays. Potential interacting residues between ROS1 and RNase7 were predicted using a protein-protein docking approach. The oncogenic function of RNase7 was analyzed by cell proliferation, migration and invasion assays, and a xenograft mouse model. The efficacy of anti-ROS1 inhibitor treatment was evaluated in patient-derived xenograft (PDX) and orthotopic models. Two independent patient cohorts were analyzed to evaluate the pathological relevance of RNase7/ROS1. RESULTS: RNase7 associated with ROS1's N3-P2 domain and promoted ROS1-mediated oncogenic transformation. Patients with HCC exhibited elevated plasma RNase7 levels compared with healthy individuals. High ROS1 and RNase7 expression were strongly associated with poor prognosis in patients with HCC. In both HCC PDX and orthotopic mouse models, ROS1 inhibitor treatment markedly suppressed RNase7-induced tumorigenesis, leading to decreased plasma RNase7 levels and tumor shrinkage in mice. CONCLUSIONS: RNase7 serves as a high-affinity ligand for ROS1. Plasma RNase7 could be used as a biomarker to identify patients with HCC who may benefit from anti-ROS1 treatment. LAY SUMMARY: Receptor tyrosine kinases are known to be involved in tumorigenesis and have been targeted therapeutically for a number of cancers, including hepatocellular carcinoma. ROS1 is the only such receptor with kinase activity whose ligand has not been identified. Herein, we show that RNase7 acts as a ligand to activate ROS1 signaling. This has important pathophysiological and therapeutic implications. Anti-ROS1 inhibitors could be used to treatment patients with hepatocellular carcinoma and high RNase7 levels.


Asunto(s)
Carcinogénesis , Carcinoma Hepatocelular , Crizotinib/farmacología , Neoplasias Hepáticas , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Tirosina Quinasas/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Tirosina Quinasas Receptoras/metabolismo , Ribonucleasas/metabolismo , Animales , Biomarcadores de Tumor/metabolismo , Carcinogénesis/efectos de los fármacos , Carcinogénesis/metabolismo , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/metabolismo , Ensayos de Migración Celular/métodos , Proliferación Celular/efectos de los fármacos , Perfilación de la Expresión Génica/métodos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Ligandos , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/metabolismo , Ratones , Proteínas Tirosina Quinasas Receptoras/antagonistas & inhibidores , Ensayos Antitumor por Modelo de Xenoinjerto
10.
Brain Cogn ; 151: 105751, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33991840

RESUMEN

The present study aimed at identifying the brain regions which preferentially responded to music with medium degrees of key stability. There were three types of auditory stimuli. Diatonic music based strictly on major and minor scales has the highest key stability, whereas atonal music has the lowest key stability. Between these two extremes, chromatic music is characterized by sophisticated uses of out-of-key notes, which challenge the internal model of musical pitch and lead to higher precision-weighted prediction error compared to diatonic and atonal music. The brain activity of 29 adults with excellent relative pitch was measured with functional magnetic resonance imaging while they listened to diatonic music, chromatic music, and atonal random note sequences. Several frontoparietal regions showed significantly greater response to chromatic music than to diatonic music and atonal sequences, including the pre-supplementary motor area (extending into the dorsal anterior cingulate cortex), dorsolateral prefrontal cortex, rostrolateral prefrontal cortex, intraparietal sulcus, and precuneus. We suggest that these frontoparietal regions may support working memory processes, hierarchical sequencing, and conflict resolution of remotely related harmonic elements during the predictive processing of chromatic music. This finding suggested a possible correlation between precision-weighted prediction error and the frontoparietal regions implicated in cognitive control.


Asunto(s)
Música , Adulto , Percepción Auditiva , Mapeo Encefálico , Cognición , Humanos , Imagen por Resonancia Magnética
11.
J Med Internet Res ; 23(6): e23471, 2021 06 11.
Artículo en Inglés | MEDLINE | ID: mdl-34347621

RESUMEN

BACKGROUND: In recent years, robots have been considered a new tech industry that can be used to solve the shortage in human resources in the field of health care. Also, animal-assisted therapy has been used to provide assistance, companionship, and interaction among the elderly and has been shown to have a positive impact on their emotional and psychological well-being. Both pets and robots can provide dynamic communication and positive interaction patterns. However, preferences for middle-aged and older adults in this regard are not clear. OBJECTIVE: This study explored the degree of acceptance of robots and pets as partners in later life and to determine the needs and preferences of elderly individuals related to companion robots. METHODS: A total of 273 middle-aged and older adults aged ≥45 years and living in the community were invited to answer a structured questionnaire after watching a companion robot video. Sociodemographic data, physical health status and activities, experience with technology, eHealth literacy, and acceptance and attitude toward robots and pets were recorded and analyzed using multinomial logistic regression analysis. RESULTS: Age, level of education, type of dwelling, occupation, retirement status, number of comorbidities, experience with pets, experience using apps, and eHealth literacy were significantly associated with acceptance of robots and pets. Middle-aged and older women preferred robots with an animal-like appearance, while men preferred robots that resembled a human adult. In terms of robot functions, participants preferred a companion robot with dancing, singing, storytelling, or news-reporting functions. Participants' marital status and whether or not they lived alone affected their preference of functions in the companion robot. CONCLUSIONS: Findings from this study inform the development of social robots with regard to their appearance and functions to address loneliness in later life in fast-aging societies.


Asunto(s)
Terapia Asistida por Animales , Robótica , Anciano , Envejecimiento , Animales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios , Taiwán
12.
Gastroenterology ; 156(6): 1849-1861.e13, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30711629

RESUMEN

BACKGROUND & AIMS: Inhibitors of MET have not produced satisfactory outcomes in trials of patients with liver cancer. We investigated the mechanisms of liver tumor resistance to MET inhibitors in mice. METHODS: We tested the effects of MET inhibitors tivantinib and capmatinib in the mouse hepatocellular carcinoma (HCC) cell line HCA-1 and in immune-competent and immunodeficient mice with subcutaneous tumors grown from this cell line. Tumors were collected from mice and tumor cells were analyzed by time-of-flight mass cytometry. We used short hairpin RNAs to weaken expression of MET in Hep3B, SK-HEP-1, HA59T, and HA22T liver cancer cell lines and analyzed cells by immunoblot, immunofluorescence, and immunoprecipitation assays. Mass spectrometry was used to assess interactions between MET and glycogen synthase kinase 3ß (GSK3B), and GSK3B phosphorylation, in liver cancer cell lines. C57/BL6 mice with orthotopic tumors grown from Hep1-6 cells were given combinations of capmatinib or tivantinib and antibodies against programmed cell death 1 (PDCD1; also called PD1); tumors were collected and analyzed by immunofluorescence. We analyzed 268 HCCsamples in a tissue microarray by immunohistochemistry. RESULTS: Exposure of liver cancer cell lines to MET inhibitors increased their expression of PD ligand 1 (PDL1) and inactivated cocultured T cells. MET phosphorylated and activated GSK3B at tyrosine 56, which decreased the expression of PDL1 by liver cancer cells. In orthotopic tumors grown in immune-competent mice, MET inhibitors decreased the antitumor activity of T cells. However, addition of anti-PD1 decreased orthotopic tumor growth and prolonged survival of mice compared with anti-PD1 or MET inhibitors alone. Tissue microarray analysis of HCC samples showed an inverse correlation between levels of MET and PDL1 and a positive correlation between levels of MET and phosphorylated GSK3B. CONCLUSIONS: In studies of liver cancer cell lines and mice with orthotopic tumors, MET mediated phosphorylation and activated GSK3B, leading to decreased expression of PDL1. Combined with a MET inhibitor, anti-PD1 and anti-PDL1 produced additive effect to slow growth of HCCs in mice.


Asunto(s)
Antígeno B7-H1/metabolismo , Carcinoma Hepatocelular/enzimología , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Neoplasias Hepáticas/enzimología , Proteínas Proto-Oncogénicas c-met/metabolismo , Factor 6 Asociado a Receptor de TNF/metabolismo , Escape del Tumor/efectos de los fármacos , Animales , Anticuerpos Monoclonales/uso terapéutico , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Antígeno B7-H1/antagonistas & inhibidores , Antígeno B7-H1/inmunología , Benzamidas , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/inmunología , Línea Celular Tumoral , Regulación hacia Abajo , Granzimas/metabolismo , Imidazoles/farmacología , Imidazoles/uso terapéutico , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/inmunología , Masculino , Ratones , Fosforilación , Proteínas Proto-Oncogénicas c-met/antagonistas & inhibidores , Pirrolidinonas/farmacología , Pirrolidinonas/uso terapéutico , Quinolinas/farmacología , Quinolinas/uso terapéutico , Factor 6 Asociado a Receptor de TNF/inmunología , Triazinas/farmacología , Triazinas/uso terapéutico , Ubiquitinación
13.
Gut ; 68(9): 1653-1666, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-30902885

RESUMEN

OBJECTIVE: In the tumour microenvironment, critical drivers of immune escape include the oncogenic activity of the tumour cell-intrinsic osteopontin (OPN), the expression of programmed death ligand 1 (PD-L1) and the expansion of tumour-associated macrophages (TAMs). We investigated the feasibility of targeting these pathways as a therapeutic option in hepatocellular carcinoma (HCC) mouse models. DESIGN: We analysed the number of tumour-infiltrating immune cells and the inflammatory immune profiles in chemically induced liver tumour isolated from wild-type and OPNknockout (KO) mice. In vitro cell cocultures were further conducted to investigate the crosstalk between TAMs and HCC cells mediated by OPN, colony stimulating factor-1 (CSF1) and CSF1 receptor (CSF1R). The in vivo efficacy of anti-PD-L1 and CSF1/CSF1R inhibition was evaluated in OPN overexpressing subcutaneous or orthotopic mouse model of HCC. RESULTS: The numbers of TAMs, as well as the expression levels of M2 macrophage markers and PD-L1 were significantly decreased, but the levels of cytokines produced by T-helper 1 (Th1) cells were upregulated in tumour tissues from OPN KO mice compared with that from the controls. In addition, we observed a positive association between the OPN and PD-L1 expression, and OPN expression and TAM infiltration in tumour tissues from patients with HCC. We further demonstrated that OPN facilitates chemotactic migration, and alternative activation of macrophages, and promotes the PD-L1 expression in HCC via activation of the CSF1-CSF1R pathway in macrophages. Combining anti-PD-L1 and CSF1R inhibition elicited potent antitumour activity and prolonged survival of OPNhigh tumour-bearing mice. Histological, flow cytometric and ELISA revealed increased CD8+ T cell infiltration, reduced TAMs and enhanced Th1/Th2 cytokine balance in multiple mouse models of HCC. CONCLUSIONS: OPN/CSF1/CSF1R axis plays a critical role in the immunosuppressive nature of the HCC microenvironment. Blocking CSF1/CSF1R prevents TAM trafficking and thereby enhances the efficacy of immune checkpoint inhibitors for the treatment of HCC.


Asunto(s)
Antígeno B7-H1/antagonistas & inhibidores , Carcinoma Hepatocelular/inmunología , Neoplasias Hepáticas/inmunología , Factor Estimulante de Colonias de Macrófagos/inmunología , Macrófagos/inmunología , Aminopiridinas/farmacología , Aminopiridinas/uso terapéutico , Animales , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Antígeno B7-H1/metabolismo , Biomarcadores de Tumor/metabolismo , Carcinoma Hepatocelular/tratamiento farmacológico , Quimiotaxis/inmunología , Citocinas/biosíntesis , Eliminación de Gen , Humanos , Neoplasias Hepáticas/tratamiento farmacológico , Linfocitos Infiltrantes de Tumor/inmunología , Factor Estimulante de Colonias de Macrófagos/antagonistas & inhibidores , Masculino , Ratones Noqueados , Terapia Molecular Dirigida/métodos , Osteopontina/genética , Osteopontina/inmunología , Pronóstico , Pirroles/farmacología , Pirroles/uso terapéutico , Células Tumorales Cultivadas , Escape del Tumor/inmunología , Microambiente Tumoral/inmunología
14.
Hum Brain Mapp ; 40(11): 3192-3202, 2019 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-30941797

RESUMEN

Nonrapid eye movement (NREM) sleep is associated with fading consciousness in humans. Recent neuroimaging studies have demonstrated the spatiotemporal alterations of the brain functional connectivity (FC) in NREM sleep, suggesting the changes of information integration in the sleeping brain. However, the common stationarity assumption in FC does not satisfactorily explain the dynamic process of information integration during sleep. The dynamic FC (dFC) across brain networks is speculated to better reflect the time-varying information propagation during sleep. Accordingly, we conducted simultaneous EEG-fMRI recordings involving 12 healthy men during sleep and observed dFC across sleep stages using the sliding-window approach. We divided dFC into two aspects: mean dFC (dFCmean ) and variance dFC (dFCvar ). A high dFCmean indicates stable brain network integrity, whereas a high dFCvar indicates instability of information transfer within and between functional networks. For the network-based dFC, the dFCvar were negatively correlated with the dFCmean across the waking and three NREM sleep stages. As sleep deepened, the dFCmean decreased (N0~N1 > N2 > N3), whereas the dFCvar peaked during the N2 stage (N0~N1 < N3 < N2). The highest dFCvar during the N2 stage indicated the unstable synchronizations across the entire brain. In the N3 stage, the overall disrupted network integration was observed through the lowest dFCmean and elevated dFCvar, compared with N0 and N1. Conclusively, when the network specificity (dFCmean ) breaks down, the consciousness dissipates with increasing variability of information exchange (dFCvar ).


Asunto(s)
Encéfalo/diagnóstico por imagen , Estado de Conciencia/fisiología , Red Nerviosa/diagnóstico por imagen , Fases del Sueño/fisiología , Adulto , Encéfalo/fisiología , Mapeo Encefálico , Electroencefalografía , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Red Nerviosa/fisiología , Vías Nerviosas/diagnóstico por imagen , Vías Nerviosas/fisiología , Adulto Joven
15.
Acta Radiol ; 60(1): 61-67, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29665705

RESUMEN

BACKGROUND: Multiple rounds of head computed tomography (CT) scans increase the risk of radiation-induced lens opacification. PURPOSE: To investigate the effects of CT eye shielding and topogram-based tube current modulation (TCM) on the radiation dose received by the lens and the image quality of nasal and periorbital imaging. MATERIAL AND METHODS: An anthropomorphic phantom was CT-scanned using either automatic tube current modulation or a fixed tube current. The lens radiation dose was estimated using cropped Gafchromic films irradiated with or without a shield over the orbit. Image quality, assessed using regions of interest drawn on the bilateral extraorbital areas and the nasal bone with a water-based marker, was evaluated using both a signal-to-noise ratio (SNR) and contrast-noise ratio (CNR). Two CT specialists independently assessed image artifacts using a three-point Likert scale. RESULTS: The estimated radiation dose received by the lens was significantly lower when barium sulfate or bismuth-antimony shields were used in conjunction with a fixed tube current (22.0% and 35.6% reduction, respectively). Topogram-based TCM mitigated the beam hardening-associated artifacts of bismuth-antimony and barium sulfate shields. This increased the SNR by 21.6% in the extraorbital region and the CNR by 7.2% between the nasal bones and extraorbital regions. The combination of topogram-based TCM and barium sulfate or bismuth-antimony shields reduced lens doses by 12.2% and 27.2%, respectively. CONCLUSION: Image artifacts induced by the bismuth-antimony shield at a fixed tube current for lenticular radioprotection were significantly reduced by topogram-based TCM, which increased the SNR of the anthropomorphic nasal bones and periorbital tissues.


Asunto(s)
Encéfalo/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador/métodos , Cristalino , Protección Radiológica/métodos , Tomografía Computarizada por Rayos X/métodos , Cabeza/diagnóstico por imagen , Neuroimagen/métodos , Fantasmas de Imagen , Dosis de Radiación
17.
Mol Cell ; 36(1): 131-40, 2009 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-19818716

RESUMEN

IkappaB kinase beta (IKKbeta) is involved in tumor development and progression through activation of the nuclear factor (NF)-kappaB pathway. However, the molecular mechanism that regulates IKKbeta degradation remains largely unknown. Here, we show that a Cullin 3 (CUL3)-based ubiquitin ligase, Kelch-like ECH-associated protein 1 (KEAP1), is responsible for IKKbeta ubiquitination. Depletion of KEAP1 led to the accumulation and stabilization of IKKbeta and to upregulation of NF-kappaB-derived tumor angiogenic factors. A systematic analysis of the CUL3, KEAP1, and RBX1 genomic loci revealed a high percentage of genome loss and missense mutations in human cancers that failed to facilitate IKKbeta degradation. Our results suggest that the dysregulation of KEAP1-mediated IKKbeta ubiquitination may contribute to tumorigenesis.


Asunto(s)
Quinasa I-kappa B/metabolismo , Péptidos y Proteínas de Señalización Intracelular/fisiología , FN-kappa B/metabolismo , Transducción de Señal/fisiología , Animales , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Línea Celular , Línea Celular Tumoral , Proteínas Cullin/genética , Proteínas Cullin/metabolismo , Variaciones en el Número de Copia de ADN/genética , Femenino , Expresión Génica/efectos de los fármacos , Expresión Génica/genética , Humanos , Quinasa I-kappa B/genética , Interleucina-8/genética , Estimación de Kaplan-Meier , Proteína 1 Asociada A ECH Tipo Kelch , Ratones , Mutación/fisiología , Neoplasias/genética , Neoplasias/metabolismo , Neovascularización Fisiológica/genética , Unión Proteica/fisiología , Dominios y Motivos de Interacción de Proteínas/fisiología , ARN Interferente Pequeño/genética , Transducción de Señal/efectos de los fármacos , Factor de Transcripción ReIA/metabolismo , Transfección , Factor de Necrosis Tumoral alfa/farmacología , Ubiquitinación/fisiología
18.
Phys Rev Lett ; 113(25): 258103, 2014 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-25554910

RESUMEN

Firefly luminescence is an intriguing phenomenon with potential technological applications, whose biochemistry background was only recently established. The physics side of this phenomenon, however, was still unclear, specifically as far as the oxygen supply mechanism for light flashing is concerned. This uncertainty is due to the complex microscopic structure of the tracheal system: without fully knowing its geometry, one cannot reliably test the proposed mechanisms. We solved this problem using synchrotron phase contrast microtomography and transmission x-ray microscopy, finding that the oxygen consumption corresponding to mitochondria functions exceeds the maximum rate of oxygen diffusion from the tracheal system to the photocytes. Furthermore, the flashing mechanism uses a large portion of this maximum rate. Thus, the flashing control requires passivation of the mitochondria functions, e.g., by nitric oxide, and switching of the oxygen supply from them to photoluminescence.


Asunto(s)
Luciérnagas/metabolismo , Oxígeno/metabolismo , Animales , Luminiscencia , Mitocondrias/metabolismo , Óxido Nítrico/metabolismo , Consumo de Oxígeno , Microtomografía por Rayos X/métodos
19.
Neuropsychologia ; 194: 108778, 2024 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-38147907

RESUMEN

Principal themes, particularly choruses in pop songs, hold a central place in human music. Singing along with a familiar chorus tends to elicit pleasure and a sense of belonging, especially in group settings. These principal themes, which frequently serve as musical rewards, are commonly preceded by distinctive musical cues. Such cues guide listeners' attention and amplify their motivation to receive the impending themes. Despite the significance of cue-theme sequences in music, the neural mechanisms underlying the processing of these sequences in unfamiliar songs remain underexplored. To fill this research gap, we employed fMRI to examine neural activity during the cued anticipation of unfamiliar musical themes and the subsequent receipt of their opening phrase. Twenty-three Taiwanese participants underwent fMRI scans while listening to excerpts of Korean slow pop songs unfamiliar to them, with lyrics they could not understand. Our findings revealed distinct temporal dynamics in lateral frontal activity, with posterior regions being more active during theme anticipation and anterior regions during theme receipt. During anticipation, participants reported substantial increases in arousal levels, aligning with the observed enhanced activity in the midbrain, ventral striatum, inferior frontal junction, and premotor regions. We posit that when motivational musical cues are detected, the ventral striatum and inferior frontal junction played a role in attention allocation, while premotor regions may be engaged in monitoring the theme's entry. Notably, both the anticipation and receipt of themes were associated with pronounced activity in the frontal eye field, dorsolateral prefrontal cortex, posterior parietal cortex, dorsal caudate, and salience network. Overall, our results highlight that within a naturalistic music-listening context, the dynamic interplay between the frontoparietal, dopaminergic midbrain-striatal, and salience networks could allow for precise adjustments of control demands based on the cue-theme structure in unfamiliar songs.


Asunto(s)
Señales (Psicología) , Música , Humanos , Música/psicología , Motivación , Imagen por Resonancia Magnética , Cognición , Mapeo Encefálico
20.
Cell Rep ; 43(1): 113641, 2024 01 23.
Artículo en Inglés | MEDLINE | ID: mdl-38165805

RESUMEN

Immune checkpoint blockade (ICB) is a promising therapy for solid tumors, but its effectiveness depends on biomarkers that are not precise. Here, we utilized genome-wide association study to investigate the association between genetic variants and tumor mutation burden to interpret ICB response. We identified 16 variants (p < 5 × 10-8) probed to 17 genes on 9 chromosomes. Subsequent analysis of one of the most significant loci in 19q13.11 suggested that the rs111308825 locus at the enhancer is causal, as its A allele impairs KLF2 binding, leading to lower carbohydrate sulfotransferase 8 (CHST8) expression. Breast cancer cells expressing CHST8 suppress T cell activation, and Chst8 loss attenuates tumor growth in a syngeneic mouse model. Further investigation revealed that programmed death-ligand 1 (PD-L1) and its homologs could be sulfated by CHST8, resulting in M2-like macrophage enrichment in the tumor microenvironment. Finally, we confirmed that low-CHST8 tumors have better ICB response, supporting the genetic effect and clinical value of rs111308825 for ICB efficacy prediction.


Asunto(s)
Carbohidrato Sulfotransferasas , Neoplasias , Ratones , Animales , Estudio de Asociación del Genoma Completo , Neoplasias/patología , Inmunoterapia/métodos , Microambiente Tumoral , Antígeno B7-H1/genética
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