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1.
Sci Rep ; 14(1): 7847, 2024 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-38570595

RESUMEN

Gastric cancer is a highly prevalent disease that poses a serious threat to public health. In clinical practice, gastroscopy is frequently used by medical practitioners to screen for gastric cancer. However, the symptoms of gastric cancer at different stages of advancement vary significantly, particularly in the case of early gastric cancer (EGC). The manifestations of EGC are often indistinct, leading to a detection rate of less than 10%. In recent years, researchers have focused on leveraging deep learning algorithms to assist medical professionals in detecting EGC and thereby improve detection rates. To enhance the ability of deep learning to detect EGC and segment lesions in gastroscopic images, an Improved Mask R-CNN (IMR-CNN) model was proposed. This model incorporates a "Bi-directional feature extraction and fusion module" and a "Purification module for feature channel and space" based on the Mask R-CNN (MR-CNN). Our study includes a dataset of 1120 images of EGC for training and validation of the models. The experimental results indicate that the IMR-CNN model outperforms the original MR-CNN model, with Precision, Recall, Accuracy, Specificity and F1-Score values of 92.9%, 95.3%, 93.9%, 92.5% and 94.1%, respectively. Therefore, our proposed IMR-CNN model has superior detection and lesion segmentation capabilities and can effectively aid doctors in diagnosing EGC from gastroscopic images.


Asunto(s)
Aprendizaje Profundo , Neoplasias Gástricas , Humanos , Gastroscopía , Neoplasias Gástricas/diagnóstico por imagen , Gastroscopios
3.
Sensors (Basel) ; 23(23)2023 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-38067802

RESUMEN

4D millimeter wave (mmWave) imaging radar is a new type of vehicle sensor technology that is critical to autonomous driving systems due to its lower cost and robustness in complex weather. However, the sparseness and noise of point clouds are still the main problems restricting the practical application of 4D imaging radar. In this paper, we introduce SMIFormer, a multi-view feature fusion network framework based on 4D radar single-modal input. SMIFormer decouples the 3D point cloud scene into 3 independent but interrelated perspectives, including bird's-eye view (BEV), front view (FV), and side view (SV), thereby better modeling the entire 3D scene and overcoming the shortcomings of insufficient feature representation capabilities under single-view built from extremely sparse point clouds. For multi-view features, we proposed multi-view feature interaction (MVI) to exploit the inner relationship between different views by integrating features from intra-view interaction and cross-view interaction. We evaluated the proposed SMIFormer on the View-of-Delft (VoD) dataset. The mAP of our method reached 48.77 and 71.13 in the fully annotated area and the driving corridor area, respectively. This shows that 4D radar has great development potential in the field of 3D object detection.

4.
Eur J Cancer ; 147: 63-73, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33618200

RESUMEN

OBJECTIVE: The mechanisms underlying the contribution of primary tumour to pre-metastatic niche formation remains largely unknown in hepatocellular carcinoma (HCC). We previously reported that the released LOXL2 from HCC cells under higher stiffness stimulation facilitated the formation of lung pre-metastatic niche. Here, we further clarified the pathological role of LOXL2 in promoting lung pre-metastatic niche formation and lung metastasis occurrence in HCC and its relevant molecular mechanism. METHODS: Using two different animal models and an in vitro system of mechanically tuneable gel mirroring lung tissue stiffness, we explored the underlying mechanism of LOXL2 in pre-metastatic niche formation. RESULTS: We applied tail vein injection of CM-LV-LOXL2-OEsimulating tumour-released soluble factors to induce lung pre-metastatic niche formation and found that the injected LOXL2 remarkably enhanced CD11b+/CD45+ bone marrow-derived cells (BMDCs) recruitment and fibronectin expression in lung. Subsequently, LOXL2-overexpressed xenograft HCC models validated that tumour-secreted LOXL2 significantly promoted the occurrence of pulmonary metastasis. In vitro, LOXL2 and LOXL2-caused matrix stiffening not only obviously upregulated the expressions of MMP9 and fibronectin in lung fibroblasts, but also evidently increased the number of adherent HCC cells and the expression of chemokine CXCL12. The activation of PI3K-AKT pathway mediated LOXL2-upregulated fibronectin. HCC patients in High-LOXL2 group had higher ratio of tumour recurrence than HCC patients in Low-LOXL2 group, supporting a significance of LOXL2 in HCC progression and unfavourable outcome. CONCLUSION: Primary tumour-released LOXL2 promotes lung pre-metastatic niche formation and lung metastasis occurrence. LOXL2-caused matrix stiffening synergistically regulates lung pre-metastatic niche formation. Targeting LOXL2-induced lung pre-metastatic niche may be a novel intervention approach against HCC metastasis.


Asunto(s)
Aminoácido Oxidorreductasas/metabolismo , Carcinoma Hepatocelular/enzimología , Neoplasias Hepáticas/enzimología , Neoplasias Pulmonares/enzimología , Microambiente Tumoral , Aminoácido Oxidorreductasas/genética , Animales , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/secundario , Línea Celular Tumoral , Quimiocina CXCL12/metabolismo , Matriz Extracelular/genética , Matriz Extracelular/metabolismo , Matriz Extracelular/patología , Femenino , Fibroblastos/enzimología , Fibroblastos/patología , Fibronectinas/metabolismo , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/secundario , Masculino , Metaloproteinasa 9 de la Matriz/metabolismo , Ratones Endogámicos BALB C , Ratones Desnudos , Persona de Mediana Edad , Fosfatidilinositol 3-Quinasa/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal
5.
FEBS J ; 288(11): 3465-3477, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-32964626

RESUMEN

Previously, we reported that the secreted lysyl oxidase like 2 (LOXL2) from hepatocellular carcinoma (HCC) cells under higher stiffness stimulation contributed to the formation of lung premetastatic niche. To further clarify whether matrix stiffness also alters LOXL2 expression in other cells within tumor microenvironment, we developed a gel-based culture system combined with a model of macrophage polarization to evaluate the effects of matrix stiffness on the polarization of M2 macrophages and their LOXL2 expression. THP-1 cells cultured on 6KPa, 10KPa, and 16KPa stiffness substrates were first incubated with 100nM phorbol 12-myristate 13-acetate (PMA) for 24 hours and subsequently treated with 20nM interleukin-4 (IL-4) and 20nM interleukin-13 (IL-13) for 48 hours. The polarization states of M2 macrophages under different stiffness stimulation were comparatively analyzed, and their LOXL2 expressions as well as the underlying molecular mechanism were further explored. Our results demonstrated that increased matrix stiffness remarkably strengthened M2 macrophage polarization and promoted their LOXL2 expression. Activation of integrin ß5-FAK-MEK1/2-ERK1/2 pathway participated in matrix stiffness-mediated HIF-1α upregulation, and HIF-1α upregulation resulted in a significant improvement in LOXL2 expression. Additionally, M2 macrophage polarization state and LOXL2 expression in HCC tissues with COL1High /LOXHigh were consistent with the results in vitro, further confirming the regulation roles of matrix stiffness in macrophage polarization and LOXL2 expression. The findings about LOXL2 upregulation in the polarized macrophages under higher stiffness stimulation will be helpful to better understand the underlying mechanism of matrix stiffness-induced premetastatic niche formation in HCC.


Asunto(s)
Aminoácido Oxidorreductasas/genética , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Macrófagos/efectos de los fármacos , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Quinasa 1 de Adhesión Focal/genética , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Cadenas beta de Integrinas/genética , Interleucina-13/farmacología , Interleucina-4/farmacología , Neoplasias Hepáticas/patología , Sistema de Señalización de MAP Quinasas/genética , Macrófagos/metabolismo
6.
Life Sci ; 259: 118244, 2020 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-32791145

RESUMEN

AIM: Protein therapeutics have potential to elicit immune responses resulting in undesirable anti-drug antibodies (ADA) that might affect product efficacy and patient safety, and should be assessed in animals before applying the treatment to humans. In this paper, we aim to assess the immunogenicity and toxicokinetics of the mono-PEGylated recombinant human interleukin-11 (rhIL-11), a novel protein therapeutic for the treatment of chemotherapy-induced thrombocytopenia, in repeated administration to cynomolgus monkeys. MAIN METHODS: Enzyme-linked immunosorbent assay (ELISA) methods were developed to measure ADA responses and plasma PEGylated IL-11 (PEG-IL11) concentration in monkeys. Assay parameters of immunogenicity and toxicokinetics methods were evaluated during validation in accordance with regulatory guidelines. We also employed cell-based assays to test the neutralizing activity of ADA provoked in monkeys. KEY FINDINGS: The results showed that weak immunogenicity occurred in some monkeys after receiving repeated dose of 0.1-0.3 mg/kg by subcutaneous administration and disappeared after the recovery period. More pronounced immunogenicity occurred at high dose of 0.9 mg/kg, with a higher positive rate and titer, and some ADAs had neutralizing activity, but it can be greatly reduced after recovery. Such ADAs generated in monkeys may be accounted for the plasma toxicokinetics changes of PEG-IL11 and a minor reduction in systemic exposure. SIGNIFICANCE: These methods have been successfully applied to immunogenicity and toxicokinetic studies of PEG-IL11 in repeated dose toxicity following subcutaneous administration to monkeys, and could be successfully used in clinical trials after some modifications.


Asunto(s)
Interleucina-11/inmunología , Interleucina-11/uso terapéutico , Animales , Anticuerpos Monoclonales/inmunología , Ensayo de Inmunoadsorción Enzimática/métodos , Humanos , Fenómenos Inmunogenéticos/genética , Fenómenos Inmunogenéticos/fisiología , Interleucina-11/metabolismo , Macaca fascicularis/inmunología , Preparaciones Farmacéuticas , Polietilenglicoles/farmacología , Proteínas Recombinantes/uso terapéutico , Toxicocinética
7.
J Mol Neurosci ; 70(9): 1445-1450, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32468216

RESUMEN

Emerging evidence has suggested that patients with ischemic stroke (IS) and/or transient ischemic attack (TIA) are more likely to exhibit myocardial disorders, which can be reflected by transthoracic echocardiography (TTE). ATP binding cassette transporter 1 (ABCB1) plays an important role in the development and progression of atherosclerotic pathology. The objective of the current study was to investigate the associations of ABCB1 C3435T polymorphism with echocardiographic performances among patients with acute ischemic stroke. Patients with IS or TIA, who were hospitalized and received TTE between October 2016 to March 2019, were enrolled in this study. Demographic data and echocardiographic parameters of each participant were recorded. We included 122 patients, with the respective distribution of 12.30%, 48.36%, and 39.34% in CC, CT, and TT genotypes. There were significant differences among the three ABCB1 types, with respect to RV (P = 0.036). The presence of the TT genotype was associated with increased MVE (OR = 0.13, P = 0.02) but correlated with decreased RV (OR = -1.46, P = 0.02). Our study indicated that ABCB1 C3435T polymorphism is associated with echocardiographic parameters among patients with acute ischemic stroke. The presence of the TT genotype is associated with diastolic function and cardiac hypertrophy.


Asunto(s)
Aterosclerosis/genética , Ataque Isquémico Transitorio/genética , Accidente Cerebrovascular Isquémico/genética , Polimorfismo de Nucleótido Simple , Subfamilia B de Transportador de Casetes de Unión a ATP/genética , Adulto , Anciano , Aterosclerosis/diagnóstico por imagen , Femenino , Humanos , Ataque Isquémico Transitorio/diagnóstico por imagen , Accidente Cerebrovascular Isquémico/diagnóstico por imagen , Masculino , Persona de Mediana Edad
8.
Biomed Chromatogr ; 33(4): e4454, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30520061

RESUMEN

Danhong injection (DHI) is made from Salvia miltiorrhiza Bunge. and Carthamus tinctorius L. extract and is widely used in the clinical treatment of cardiovascular and cerebrovascular diseases. This study aimed to evaluate the effect of DHI on cytochrome P450 (CYP450) enzymes in vitro to predict drug-drug interactions based on CYP450 as combination therapy. To assess the inhibitory effect of DHI on CYP450, we detected the IC50 value of DHI on CYP450 in vitro by liquid chromatography/tandem mass spectrometry (LC-MS/MS). Simultaneously, the induction effect of DHI on CYP450s was also evaluated. The relative induction ratios of DHI on CYP1A2, CYP2B6 and CYP3A4 activity were calculated by LC-MS/MS. The expression level of CYP3A4 mRNA was determined by reverse transcription PCR (RT-PCR). The LC-MS/MS data showed DHI intensively inhibit CYP2A6 activity and the intensity of inhibition was followed by CYP2C8, CYP3A4, CYP2C19, CYP2B6, CYP2D6, CYP1A2, CYP2E1 and CYP2C9 in vitro. The results of RT-PCR showed that there is a certain induction of DHI on CYP3A4 mRNA in human primary hepatocytes in vitro. The study suggested that drug-drug interactions might occur in clinical co-administration of drugs owing to the CYP2A6 inhibition and CYP3A4 induction.


Asunto(s)
Sistema Enzimático del Citocromo P-450/análisis , Sistema Enzimático del Citocromo P-450/metabolismo , Medicamentos Herbarios Chinos/farmacología , Animales , Células Cultivadas , Cromatografía Líquida de Alta Presión , Hepatocitos/efectos de los fármacos , Hepatocitos/metabolismo , Humanos , Masculino , Ratas , Ratas Sprague-Dawley , Espectrometría de Masas en Tándem
9.
Toxicol Appl Pharmacol ; 342: 39-49, 2018 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-29407773

RESUMEN

The mono-PEGylated recombinant human interleukin-11 (rhIL-11) was evaluated for its pharmacology and toxicology profile in non-human primates. This PEGylated IL-11 (PEG-IL11) showed a much prolonged circulating half-life of 67h in cynomolgus monkeys as compared to its un-PEGylated counterpart (~3h) through subcutaneous administration, implicating that a single injection of the recommended dose will effectively enhance thrombopoiesis in humans for a much longer period of time compared to rhIL-11 in humans (t1/2=6.9h). The toxicokinetics study of single dose and multiple doses showed that systemic exposure was positively correlated with the dosing level, implying that efficacy and toxicity were mechanism-based. A single high dose at 6.25mg/kg through subcutaneous route revealed tolerable and transient toxicity. Multiple-dose in monkeys receiving 0.3mg/kg weekly of the drug developed only mild to moderate toxicity. Major adverse events and immunogenicity in monkeys were only observed in the overdose groups. Bones were positively impacted; while reversible toxicities in heart, liver, kidney and lung observed were likely to be consequences of fluid retention. In summary, the PEG moiety on rhIL-11 did not elicit additional toxicities, and the drug under investigation was found to be well tolerated in monkeys after receiving a single effective dose of 0.1-0.3mg/kg through subcutaneous delivery, which may be allometrically scaled to a future clinical dose at 30-100µg/kg, creating a potential long acting, safer, and more convenient treatment approach based on rhIL-11.


Asunto(s)
Interleucina-11/administración & dosificación , Polietilenglicoles/administración & dosificación , Animales , Densidad Ósea/efectos de los fármacos , Densidad Ósea/fisiología , Relación Dosis-Respuesta a Droga , Evaluación Preclínica de Medicamentos/métodos , Femenino , Humanos , Inyecciones Subcutáneas , Interleucina-11/química , Interleucina-11/toxicidad , Hígado/efectos de los fármacos , Hígado/metabolismo , Pulmón/efectos de los fármacos , Pulmón/metabolismo , Macaca fascicularis , Masculino , Polietilenglicoles/química , Polietilenglicoles/toxicidad , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/química , Proteínas Recombinantes/toxicidad
10.
Life Sci ; 191: 205-210, 2017 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-29054454

RESUMEN

AIMS: Cellular senescence and matrix metalloproteinases (MMPs) play an important role in liver diseases. The source and regulating factors of MMPs in senescent hepatocytes are not known. We investigated whether senescent hepatocytes secreted MMPs and if this was regulated by nuclear factor (NF)-κB. MATERIALS AND METHODS: The TGF-α transgenic mouse hepatocyte line AML12 was treated with H2O2 to induce senescence. NF-κB signaling was examined by Western blotting and luciferase reporter assays. Quantitative reverse transcription polymerase chain reaction was used to evaluated expression of MMP-2, -9 and -13. KEY FINDINGS: AML12 cells treated with H2O2 showed the characteristic morphology of senescence. The activity of NF-κB and expression of MMP-2, -9 and -13 were increased in senescent AML12 cells. The NF-κB inhibitor BAY 11-7082 decreased the levels of MMPs. SIGNIFICANCE: These results suggest that senescent hepatocytes are involved in the pathology of liver diseases through remodeling the extracellular matrix.


Asunto(s)
Senescencia Celular , Hepatocitos/metabolismo , Metaloproteinasas de la Matriz/metabolismo , FN-kappa B/metabolismo , Transducción de Señal , Animales , Línea Celular , Hepatocitos/citología , Peróxido de Hidrógeno/metabolismo , Ratones
11.
Toxicol Appl Pharmacol ; 334: 1-7, 2017 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-28867436

RESUMEN

Diosmetin (3', 5, 7-trihydroxy-4'-methoxyflavone), a natural flavonoid from traditional Chinese herbs, has been used in various medicinal products because of its anticancer, antimicrobial, antioxidant, estrogenic and anti-inflammatory activity. However, flavonoids could affect the metabolic enzymes and cause drug-drug interactions (DDI), reducing the efficacy of co-administered drugs and potentially resulting in serious adverse reactions. To evaluate its potential to interact with co-administered drugs, the IC50 value of phase I cytochrome P450 enzymes (CYPs), phase II UDP-glucuronyltransferases (UGTs) and hepatic uptake transporters (organic cation transporters (OCTs), organic anion transporter polypeptides (OATPs) and Na+-taurocholate cotransporting polypeptides (NTCPs)) were examined in vitro by LC-MS/MS. Diosmetin showed strong inhibition of CYP1A2 in a concentration-dependent manner. The intensity of the inhibitory effect was followed by CYP2C8, CYP2C9, CYP2C19 and CYP2E1. For CYP2A6, CYP2B6, CYP2D6 and CYP3A4, diosmetin was found to have no significant inhibitory effects, and the induction effect on CYPs was not significant. For UGTs, diosmetin had a minimal inhibitory effect. In addition, the inhibitory effects of diosmetin on OATP and OCT1 were weak, and it had little effect on NTCP. This finding indicated that drug-drug interactions induced by diosmetin may occur through co-administration of drugs metabolized by CYP1A2.


Asunto(s)
Sistema Enzimático del Citocromo P-450/metabolismo , Flavonoides/química , Flavonoides/farmacología , Glicosiltransferasas/metabolismo , Hepatocitos/efectos de los fármacos , Animales , Proteínas Portadoras , Sistema Enzimático del Citocromo P-450/genética , Glicosiltransferasas/genética , Hepatocitos/metabolismo , Humanos , Isoenzimas , Masculino , Estructura Molecular , Ratas , Ratas Sprague-Dawley
12.
Mol Cancer Ther ; 16(8): 1544-1554, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28572167

RESUMEN

Colony-stimulating factor-1 (CSF-1) and its receptor, CSF-1R, regulate the differentiation and function of macrophages and play an important role in macrophage infiltration in the context of hepatocellular carcinoma. The therapeutic effects of CSF-1R blockade in hepatocellular carcinoma remain unclear. In this study, we found that CSF-1R blockade by PLX3397, a competitive inhibitor with high specificity for CSF-1R tyrosine kinase, significantly delayed tumor growth in mouse models. PLX3397 inhibited the proliferation of macrophages in vitro, but intratumoral macrophage infiltration was not decreased by PLX3397 in vivo Gene expression profiling of tumor-associated macrophages (TAM) showed that TAMs from the PLX3397-treated tumors were polarized toward an M1-like phenotype compared with those from vehicle-treated tumors. In addition, PLX3397 treatment increased CD8+ T-cell infiltration, whereas CD4+ T-cell infiltration was decreased. Further study revealed that tumor cell-derived CSF-2 protected TAMs from being depleted by PLX3397. In conclusion, CSF-1R blockade delayed tumor growth by shifting the polarization rather than the depletion of TAMs. CSF-1R blockade warrants further investigation in the treatment of hepatocellular carcinoma. Mol Cancer Ther; 16(8); 1544-54. ©2017 AACR.


Asunto(s)
Carcinoma Hepatocelular/patología , Polaridad Celular , Neoplasias Hepáticas/patología , Macrófagos/patología , Receptor de Factor Estimulante de Colonias de Macrófagos/antagonistas & inhibidores , Aminopiridinas/química , Aminopiridinas/farmacología , Aminopiridinas/uso terapéutico , Animales , Biomarcadores de Tumor/metabolismo , Células de la Médula Ósea/patología , Línea Celular Tumoral , Polaridad Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Humanos , Factor Estimulante de Colonias de Macrófagos/farmacología , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Masculino , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Modelos Biológicos , Monocitos/patología , Fenotipo , Pirroles/química , Pirroles/farmacología , Pirroles/uso terapéutico , Receptor de Factor Estimulante de Colonias de Macrófagos/metabolismo , Microambiente Tumoral/efectos de los fármacos
13.
J Biochem Mol Toxicol ; 31(7)2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28111842

RESUMEN

Cytochrome P450s are involved in detoxification and activation of benzo[a]pyrene (BaP) with unclear balance and unknown contribution of other oxidoreductases. Here, we investigated the BaP and BaP-induced mutagenicity in hepatic and extra-hepatic tissues using hepatic P450 reductase null (HRN) gpt mice. After 2-week treatment (50 mg/kg, i.p. 4 days), BaP in the liver and lung of HRN-gpt mice were increased. BaP promoted gpt mutant frequency (MF) in HRN-gpt mice liver. MF of gpt in the lung and Pig-a in hematopoietic cells induced by BaP in HRN-gpt mice were increased than in gpt mice. BaP-7,8-diol-9,10-epoxide (BPDE)-DNA adducts in vitro was analyzed for enzymes detection in BaP bioactivation. Specific inhibitors of 5-lipoxygenase, cyclooxygenase-1&2, and aldo-keto reductase resulted in more than 80% inhibition rate in the DNA adduct formation, further confirmed by Macaca fascicularis hepatic S9 system. Our results suggested the detoxification of BaP primarily depends on cytochrome P450, while the bioactivation involves additional oxidoreductases.


Asunto(s)
Aldo-Ceto Reductasas/metabolismo , Araquidonato 5-Lipooxigenasa/metabolismo , Benzo(a)pireno/farmacocinética , Sistema Enzimático del Citocromo P-450/metabolismo , Hígado/enzimología , Aldo-Ceto Reductasas/genética , Animales , Araquidonato 5-Lipooxigenasa/genética , Benzo(a)pireno/farmacología , Sistema Enzimático del Citocromo P-450/genética , Células Madre Hematopoyéticas/enzimología , Inactivación Metabólica , Macaca fascicularis , Ratones , Ratones Noqueados
14.
Acta Pharmacol Sin ; 37(5): 708-18, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27063220

RESUMEN

AIM: The substrate cocktail is frequently used to evaluate cytochrome P450 (CYP) enzyme-mediated drug interactions and potential interactions among the probe substrates. Here, we re-optimized the substrate cocktail method to increase the reliability and accuracy of screening for candidate compounds and expanded the method from a direct CYP inhibition assay to a time-dependent inhibition (TDI) assay. METHODS: In the reaction mixtures containing human liver microsome (0.1 mg/mL), both the concentrations of a substrate cocktail (phenacetin for 1A2, coumarin for 2A6, bupropion for 2B6, diclofenac for 2C9, dextromethorphan for 2D6, and testosterone for 3A4) and the incubation time were optimized. Metabolites of the substrate probes were simultaneously analyzed by multiple-reaction monitoring (MRM) using a routine LC/MS/MS. Direct CYP inhibition was validated using 7 inhibitors (α-naphthoflavone, tranylcypromine, ticlopidine, fluconazole, quinidine, ketoconazole and 1-ABT). The time-dependent inhibition was partially validated with 5 inhibitors (ketoconazole, verapamil, quinidine, paroxetine and 1-ABT). RESULTS: The inhibition curve profiles and IC50 values of 7 CYP inhibitors were approximate when a single substrate and the substrate cocktail were tested, and were consistent with the previously reported values. Similar results were obtained in the IC50 shifts of 5 inhibitors when a single substrate and the substrate cocktail were tested in the TDI assay. CONCLUSION: The 6-in-1 substrate cocktail (for 1A2, 2A6, 2B6, 2C9, 2D6 and 3A) is reliable for assessing CYP inhibition and time-dependent inhibition of drug candidates.


Asunto(s)
Inhibidores Enzimáticos del Citocromo P-450/farmacología , Sistema Enzimático del Citocromo P-450/metabolismo , Evaluación Preclínica de Medicamentos/métodos , Interacciones Farmacológicas , Humanos , Microsomas Hepáticos/efectos de los fármacos , Microsomas Hepáticos/enzimología , Especificidad por Sustrato , Factores de Tiempo
15.
Springerplus ; 4: 652, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26543786

RESUMEN

Hetrombopag as the derivative of ethylidene hydrazine carboxamide was recently developed into a novel patented non-peptide thrombopoietin mimetic and thrombopoietin receptor agonist to treat idiopathic thrombocytopenic purpura. To study the pharmacokinetics of hetrombopag, a highly sensitive, rapid and reliable liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated for determination of hetrombopag in rat plasma. After protein precipitation extraction, the chromatography separation of analyte and internal standard named eltrombopag as an marketed analog of hetrombopag was performed on an Synergi Polar-RP column at the flow rate of 0.5 mL/min, and the determination was conducted on an API4000 triple quadrupole mass spectrometry in the multiple reaction monitoring mode using the respective [M+H](+) ions m/z 459.2 â†’ 200.9 for hetrombopag and m/z 443.2 â†’ 229.0 for IS. The lower limit of quantification was established to be 1 ng/mL, and the linear scope of standard curve was 1-1000 ng/mL. Both the precision (RSD%) and accuracy (RE%) were within the acceptable criterion of below 15 %. The validated method was successfully applied to quantify hetrombopag in the rat plasma and investigate the pharmacokinetics.

16.
Oncotarget ; 6(37): 40068-80, 2015 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-26517671

RESUMEN

Chronic fibrosis is a major risk factor for the development of hepatocellular carcinoma (HCC). The pathological progression of hepatic fibrosis has been linked to cellular processes that promote tumor growth and metastasis. Several recent studies have highlighted the cross-talk between tumor cells and activated hepatic stellate cells (aHSCs) in HCC. The herbal compound Songyou Yin (SYY) is known to attenuate hepatoma cell invasion and metastasis via down-regulation of cytokine secretion by aHSCs. However the underlying mechanism of SYY treatment in reversal of hepatic fibrosis and metastasis of liver cancers is not known. In the current study, a nude mouse model with liver fibrosis bearing orthotopic xenograft was established and we found that SYY could reduce associated fibrosis, inhibit tumor growth and improve survival. In the subcutaneous tumor model with fibrosis, we found that SYY could inhibit liver cancer. In vitro, hepatoma cells incubated with conditioned media (CM) from SYY treated aHSCs showed reduced proliferation, decrease in colony formation and invasive potential. SYY treated group showed altered gene expression, with 1205 genes up-regulated and 1323 genes down-regulated. Gene cluster analysis indicated that phosphatidylinositol-3-kinase (PI3K) was one of the key genes altered in the expression profiles. PI3K related markers were all significantly down-regulated. ELISA also indicated decreased secretion of cytokines which were regulated by PI3K/AKT signaling after SYY treatment in the hepatic stellate cell line, LX2. These data clearly demonstrate that SYY therapy inhibits HCC invasive and metastatic potential and improves survival in nude mice models with chronic fibrosis background via inhibition of cytokine secretion by activated hepatic stellate cells.


Asunto(s)
Carcinoma Hepatocelular/prevención & control , Medicamentos Herbarios Chinos/farmacología , Células Estrelladas Hepáticas/efectos de los fármacos , Cirrosis Hepática/tratamiento farmacológico , Neoplasias Hepáticas/prevención & control , Animales , Western Blotting , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Línea Celular , Línea Celular Tumoral , Enfermedad Crónica , Citocinas/genética , Citocinas/metabolismo , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Células Estrelladas Hepáticas/metabolismo , Humanos , Cirrosis Hepática/genética , Cirrosis Hepática/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Masculino , Ratones Endogámicos BALB C , Ratones Desnudos , Comunicación Paracrina/efectos de los fármacos , Comunicación Paracrina/genética , Fosfatidilinositol 3-Quinasas/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Fitoterapia/métodos , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Análisis de Supervivencia , Carga Tumoral/efectos de los fármacos , Carga Tumoral/genética , Ensayos Antitumor por Modelo de Xenoinjerto
17.
Chem Commun (Camb) ; 51(51): 10337-40, 2015 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-26027699

RESUMEN

Cu2ZnSnS4 thin films with thicknesses ranging from 0.35 to 1.85 µm and micron-sized grains (0.5-1.5 µm) were synthesized using co-electrodeposited Cu-Zn-Sn-S precursors with different deposition times. Here we have introduced a sputtered CdS buffer layer for the development of CZTS solar cells for the first time, which enables breakthrough efficiencies up to 6.6%.

18.
J Hematol Oncol ; 7: 28, 2014 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-24678763

RESUMEN

BACKGROUND: Cancer stem cells (CSCs) play a key role in the posthepatectomy recurrence of hepatocellular carcinoma (HCC). CD133+ HCC cells exhibit liver CSC-like properties, and CSC differentiation-inducing therapy may lead these cells to lose their self-renewal ability and may induce terminal differentiation, which may in turn allow their malignant potential to be controlled. Because arsenic trioxide (As2O3) increases remission rates and prolongs survival among patients with acute promyelocytic leukemia by inducing differentiation and apoptosis of leukemic cells, we hypothesized that As2O3 might also inhibit HCC recurrence and prolong survival time after hepatectomy by inducing differentiation of HCC CSCs. METHODS: We evaluated the As2O3 induced differentiation of human HCC CSCs and its mechanism in vitro, and we investigated the effects of treatment with As2O3 on recurrence rates and median survival in a mouse xenograft model. RESULTS: We found that As2O3 induced HCC CSC differentiation by down-regulating the expression of CD133 and some stemness genes, thus inhibiting the cells' self-renewal ability and tumorigenic capacity without inhibiting their proliferation in vitro. In vivo experiments indicated that As2O3 decreased recurrence rates after radical resection and prolonged survival in a mouse model. As2O3, which shows no apparent toxicity, may induce HCC CSC differentiation by down-regulating the expression of GLI1. CONCLUSIONS: We found that As2O3 induced HCC CSC differentiation, inhibited recurrence, and prolonged survival after hepatectomy by targeting GLI1expression. Our results suggest that the clinical safety and utility of As2O3 should be further evaluated.


Asunto(s)
Antígenos CD/metabolismo , Arsenicales/farmacología , Carcinoma Hepatocelular/tratamiento farmacológico , Glicoproteínas/metabolismo , Neoplasias Hepáticas/tratamiento farmacológico , Óxidos/farmacología , Péptidos/metabolismo , Factores de Transcripción/biosíntesis , Antígeno AC133 , Animales , Trióxido de Arsénico , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/cirugía , Diferenciación Celular/efectos de los fármacos , Línea Celular Tumoral , Modelos Animales de Enfermedad , Regulación hacia Abajo , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/cirugía , Masculino , Ratones , Ratones Endogámicos NOD , Ratones SCID , Recurrencia Local de Neoplasia/metabolismo , Recurrencia Local de Neoplasia/patología , Células Madre Neoplásicas/patología , Distribución Aleatoria , Transducción de Señal , Análisis de Supervivencia , Factores de Transcripción/genética , Ensayos Antitumor por Modelo de Xenoinjerto , Proteína con Dedos de Zinc GLI1
19.
PLoS One ; 8(10): e77957, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24194905

RESUMEN

BACKGROUND & AIMS: microRNAs (miRNAs) have been reported to regulate angiogenesis by down-regulating the expression of pro-angiogenic or anti-angiogenic factors. The aims of this study were to investigate whether miR-26a inhibited angiogenesis by down-regulating vascular endothelial growth factor A (VEGFA) and its clinical relevance in hepatocellular carcinoma (HCC). METHODS: The expression of miR-26a was modified in HepG2 and HCCLM3 cell lines respectively, and a panel of angiogenic factors was measured by real-time PCR in the cells. A luciferase reporter assay was used to validate the target gene of miR-26a. Specific inhibitors of signal transduction pathway and siRNA approaches were used to explore the regulatory mechanism of miR-26a. Migration and tube forming assays were conducted to show the changes of angiogenesis induced by miR-26a and its target genes. Finally animal studies were used to further validate those findings. RESULTS: Ectopic expression of miR-26a exhibited decreased levels of VEGFA in HepG2 cells. Migration and tube forming of human umbilical vein endothelial cells (HUVECs) were decreased in the conditioned medium from ectopic expression of miR-26a in HepG2 cells compared to control HepG2 cells. The pro-angiogenic effects of the conditioned medium of HepG2 cells on HUVECs were specifically decreased by LY294002, YC-1, and bevacizumab. Integrated analysis disclosed PIK3C2α as a downstream target gene of miR-26a. Ectopic expression of miR-26a suppressed ectopic and orthotopic tumor growth and vascularity in nude mice. The results in HCCLM3 were consistent with those in HepG2. miR-26a expression was inversely correlated with VEGFA expression in HCC patients. CONCLUSIONS: miR-26a modulated angiogenesis of HCC through the PIK3C2α/Akt/HIF-1α/VEGFA pathway. The expression of VEGFA was inversely correlated with miR-26a expression in HCC tumors.


Asunto(s)
Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/metabolismo , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/metabolismo , MicroARNs/farmacología , Neovascularización Patológica/tratamiento farmacológico , Factor A de Crecimiento Endotelial Vascular/metabolismo , Análisis de Varianza , Animales , Western Blotting , Ensayo de Inmunoadsorción Enzimática , Células Hep G2 , Células Endoteliales de la Vena Umbilical Humana , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Inmunohistoquímica , Luciferasas , Ratones , Ratones Desnudos , MicroARNs/uso terapéutico , Fosfatidilinositol 3-Quinasas/metabolismo , ARN Interferente Pequeño/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal/efectos de los fármacos
20.
PLoS One ; 8(5): e65023, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23741443

RESUMEN

BACKGROUND AIMS: We previously demonstrated the pro-metastasis effect of sorafenib in hepatocellular carcinoma (HCC), which is mediated by down-regulation of tumor suppressor HTATIP2. The aim of the present study was to determine whether aspirin minimizes this effect and improves survival. METHODS: The effects of sorafenib, aspirin, and combined sorafenib and aspirin were observed in HCCLM3 and HepG2 xenograft nude mice. Tumor growth, intrahepatic metastasis (IHM), lung metastasis, and survival were assessed. Polymerase chain reaction (PCR) array, real-time (RT)-PCR, and Western blotting were used to examine gene expression. The anti-invasion and anti-metastasis effects of aspirin were studied in HTATIP2-knockdown and HTATIP2-overexpressing HCC cell lines. The molecular mechanism of HTATIP2 regulation by aspirin was explored. RESULTS: Aspirin suppressed the pro-invasion and pro-metastasis effects of sorafenib in HCC and up-regulated HTATIP2 expression. Aspirin did not inhibit the proliferation of HCC cells, but it decreased the invasiveness of HCC with lower expression of HTATIP2 and increased expression of a set of markers, indicating a mesenchymal-to-epithelial transition in tumor cells. The up-regulation of HTATPI2 expression by aspirin is most likely mediated through inhibition of cyclooxygenase (COX) 2 expression. CONCLUSIONS: Aspirin minimized the pro-metastasis effect of sorafenib by up-regulating the tumor suppressor HTATIP2; this mechanism is mediated through inhibition of COX2.


Asunto(s)
Acetiltransferasas/genética , Aspirina/farmacología , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Niacinamida/análogos & derivados , Compuestos de Fenilurea/farmacología , Factores de Transcripción/genética , Animales , Aspirina/administración & dosificación , Carcinoma Hepatocelular/mortalidad , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Ciclooxigenasa 2/genética , Modelos Animales de Enfermedad , Transición Epitelial-Mesenquimal/efectos de los fármacos , Transición Epitelial-Mesenquimal/genética , Redes Reguladoras de Genes/efectos de los fármacos , Células Hep G2 , Humanos , Neoplasias Hepáticas/mortalidad , Masculino , Ratones , Metástasis de la Neoplasia , Niacinamida/administración & dosificación , Niacinamida/farmacología , Compuestos de Fenilurea/administración & dosificación , Sorafenib , Carga Tumoral/efectos de los fármacos , Carga Tumoral/genética , Ensayos Antitumor por Modelo de Xenoinjerto
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