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1.
Artículo en Inglés | MEDLINE | ID: mdl-38800890

RESUMEN

Natural killer (NK) cells are one of the key members of innate immunity that predominantly reside in the liver, potentiating immune responses against viral infections or malignant tumors. It has been reported that changes in cell numbers and function of NK cells are associated with the development and progression of chronic liver diseases (CLDs) including non-alcoholic fatty liver disease, alcoholic liver disease, and chronic viral hepatitis. Also, it is known that the crosstalk between NK cells and hepatic stellate cells plays an important role in liver fibrosis and cirrhosis. In particular, the impaired functions of NK cells observed in CLDs consequently contribute to occurrence and progression of hepatocellular carcinoma (HCC). Chronic infections by hepatitis B or C viruses counteract the anti-tumor immunity of the host by producing the sheddases. Soluble major histocompatibility complex class I polypeptide-related sequence A (sMICA), released from the cell surfaces by sheddases, disrupts the interaction and affects the function of NK cells. Recently, the MICA/B-NK stimulatory receptor NK group 2 member D (NKG2D) axis has been extensively studied in HCC. HCC patients with low membrane-bound MICA or high sMICA concentration have been associated with poor prognosis. Therefore, reversing the sMICA-mediated downregulation of NKG2D has been proposed as an attractive strategy to enhance both innate and adaptive immune responses against HCC. This review aims to summarize recent studies on NK cell immune signatures and its roles in CLD and hepatocellular carcinogenesis and discusses the therapeutic approaches of MICA/B-NKG2D-based or NK cell-based immunotherapy for HCC.

2.
Biomaterials ; 302: 122336, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37778055

RESUMEN

Duodenal ablation improves glycaemic control and weight loss, so it has been applied using hydrothermal catheters in obese and type 2 diabetes patients, indicating similar mechanisms and therapeutic effects as bariatric surgeries. Endoscopic photodynamic therapy is an innovative procedure that easily accessible to endocrine or gastrointestinal organs, so it is critical for the sprayed photosensitizer (PS) to long-term interact with target tissues for enhancing its effects. Surfactant-like PS was more stable in a wide range of pH and 2.8-fold more retained in the duodenum at 1 h than hydrophilic PS due to its amphiphilic property. Endoscopic duodenal ablation using surfactant-like PS was performed in high fat diet induced rat models, demonstrating body weight loss, enhanced insulin sensitivity, and modulation of incretin hormones. Locoregional ablation of duodenum could affect the profiles of overall intestinal cells secreting meal-stimulated hormones and further the systemic glucose and lipid metabolism, regarding gut-brain axis. Our strategy suggests a potential for a treatment of minimally invasive bariatric and metabolic therapy if accompanied by detailed clinical trials.


Asunto(s)
Diabetes Mellitus Tipo 2 , Humanos , Animales , Ratas , Diabetes Mellitus Tipo 2/metabolismo , Incretinas , Fármacos Fotosensibilizantes/uso terapéutico , Tensoactivos , Obesidad/cirugía , Duodeno/cirugía , Duodeno/metabolismo , Glucemia/metabolismo
3.
Adv Healthc Mater ; 12(31): e2302374, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37722358

RESUMEN

Here, a novel approach is presented to improve the efficacy of antibody-drug conjugates (ADC) by integrating antibody-mediated immunotherapy and photodynamic therapy (PDT) in a combination therapy system utilizing an antibody-photosensitizer conjugate (APC) platform based on a poloxamer polymer linker. To specifically target Kirsten rat sarcoma 2 viral oncogene homolog (KRAS)-mutated cancer cells, an antibody antiepidermal growth factor receptor (EGFR), cetuximab, with a poloxamer linker coupled with the photosensitizer chlorin e6 through click chemistry (cetuximab-maleimide-poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide)-chlorine e6 conjugate, CMPXC) is synthesized. CMPXC is cytotoxic upon laser treatment, achieving a 90% cell death by suppressing KRAS downstream signaling pathways associated with ERK and AKT proteins, confirmed using RNA sequencing analysis. In KRAS-mutated colorectal cancer mouse models, CMPXC significantly enhances antitumor efficacy compared with cetuximab treatment alone, resulting in an 86% reduction in tumor growth. Furthermore, CMPXC treatment leads to a 2.24- and 1.75-fold increase in dendritic and priming cytotoxic T cells, respectively, highlighting the immune-activating potential of this approach. The findings suggest that the APC platform addresses the challenges associated with ADC development and EGFR-targeted therapy, including the synergistic advantages of antibody-mediated immunotherapy and PDT.


Asunto(s)
Antineoplásicos , Neoplasias Colorrectales , Animales , Ratones , Cetuximab/farmacología , Cetuximab/uso terapéutico , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/uso terapéutico , Proteínas Proto-Oncogénicas p21(ras)/genética , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Proteínas Proto-Oncogénicas p21(ras)/uso terapéutico , Poloxámero , Neoplasias Colorrectales/tratamiento farmacológico , Antineoplásicos/uso terapéutico , Mutación , Receptores ErbB/genética , Receptores ErbB/metabolismo , Línea Celular Tumoral
4.
Biotechnol Appl Biochem ; 64(6): 836-842, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28791738

RESUMEN

Metformin is an AMP-activated kinase (AMPK) activator that plays a role in glucose energy metabolism and cell protection. It is widely used to treat several diseases, including type 2 diabetes, cardiovascular diseases, cancer, and metabolic diseases. In this study, we investigated whether AMPK activation upon treatment with metformin may promote neurite outgrowth during the progression of neuronal differentiation in human bone marrow-mesenchymal stem cells (hBM-MSCs). Differentiation of metformin-treated MSCs (Met-MSCs to Met-diMSCs) in the neuronal induction media resulted in an increase in the number of differentiated cells in a metformin concentration dependent manner. The differentiation rate reached its maximum at 3 H after the initial treatment with neuronal induction media. At 3 H of induction, the neurite length increased significantly in Met-diMSCs as compared with control cells without metformin treatment (diMSCs). diMSCs showed a significant increase in the expression of neuronal-specific marker genes; however, the expression of dendrite-specific markers MAP-2 and Tuj-1 was significantly increased in Met-diMSCs as compared to diMSCs, as confirmed by immunoblotting. This effect was abolished upon treatment with the AMPK inhibitor, compound C, as evident by quantitative PCR, immunoblotting, and immunocytochemical staining. Thus, metformin treatment promotes neuronal differentiation and neurite outgrowth in hBM-MSCs through AMPK activation.


Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Células Madre Mesenquimatosas/efectos de los fármacos , Metformina/farmacología , Proyección Neuronal/efectos de los fármacos , Neuronas/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Relación Dosis-Respuesta a Droga , Humanos , Células Madre Mesenquimatosas/metabolismo , Neuronas/citología , Transducción de Señal/efectos de los fármacos , Relación Estructura-Actividad
5.
J Am Chem Soc ; 138(40): 13253-13259, 2016 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-27690407

RESUMEN

Controlled lateral quantum confinement in single-layer transition-metal chalcogenides (TMCs) can potentially combine the unique properties of two-dimensional (2D) exciton with the size-tunability of exciton energy, creating the single-layer quantum dots (SQDs) of 2D TMC materials. However, exploring such opportunities has been challenging due to the limited ability to produce well-defined SQDs with sufficiently high quality and size control, in conjunction with the commonly observed inconsistency in the optical properties. Here, we report an effective method to synthesize high-quality and size-controlled SQDs of WSe2 via multilayer quantum dots (MQDs) precursors, which enables grasping a clear picture of the role of lateral confinement on the optical properties of the 2D exciton. From the single-particle optical spectra and polarization anisotropy of WSe2 SQDs of varying sizes in addition to their ensemble data, we reveal how the properties of 2D exciton in single-layer TMCs evolve with increasing lateral quantum confinement.

6.
Nat Commun ; 6: 5763, 2015 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-25575047

RESUMEN

Simple and effective generation of transition metal chalcogenides (TMCs) in a single-layer form has been a challenging task. Here we present a tandem molecular intercalation (TMI) as a new exfoliation concept for producing single-layer TMCs from multi-layer colloidal TMC nanostructures in solution phase. TMI requires tandem Lewis base intercalates, where short 'initiator' molecules first intercalate into TMCs to open up the interlayer gap, and the long 'primary' molecules then bring the gap to full width so that a random mixture of intercalates overcomes the interlayer force. Spontaneous exfoliation then yields single-layer TMCs. The TMI process is uniquely advantageous because it works in a simple one-step process under safe and mild conditions (that is, room temperature without sonication or H2 generation). With the appropriate intercalates, we have successfully generated single-layer nanostructures of group IV (TiS2, ZrS2), group V (NbS2) and VI (WSe2, MoS2) TMCs.

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