Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 45
Filtrar
Más filtros










Intervalo de año de publicación
1.
Exp Eye Res ; 242: 109852, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38460719

RESUMEN

Oxidative stress plays a pivotal role in the pathogenesis of several neurodegenerative diseases. Retinal degeneration causes irreversible death of photoreceptor cells, ultimately leading to vision loss. Under oxidative stress, the synthesis of bioactive sphingolipid ceramide increases, triggering apoptosis in photoreceptor cells and leading to their death. This study investigates the effect of L-Cycloserine, a small molecule inhibitor of ceramide biosynthesis, on sphingolipid metabolism and the protection of photoreceptor-derived 661W cells from oxidative stress. The results demonstrate that treatment with L-Cycloserine, an inhibitor of Serine palmitoyl transferase (SPT), markedly decreases bioactive ceramide and associated sphingolipids in 661W cells. A nontoxic dose of L-Cycloserine can provide substantial protection of 661W cells against H2O2-induced oxidative stress by reversing the increase in ceramide level observed under oxidative stress conditions. Analysis of various antioxidant, apoptotic and sphingolipid pathway genes and proteins also confirms the ability of L-Cycloserine to modulate these pathways. Our findings elucidate the generation of sphingolipid mediators of cell death in retinal cells under oxidative stress and the potential of L-Cycloserine as a therapeutic candidate for targeting ceramide-induced degenerative diseases by inhibiting SPT. The promising therapeutic prospect identified in our findings lays the groundwork for further validation in in-vivo and preclinical models of retinal degeneration.


Asunto(s)
Apoptosis , Ceramidas , Cicloserina , Estrés Oxidativo , Esfingolípidos , Estrés Oxidativo/efectos de los fármacos , Cicloserina/farmacología , Animales , Ceramidas/metabolismo , Ceramidas/farmacología , Ratones , Esfingolípidos/metabolismo , Apoptosis/efectos de los fármacos , Células Fotorreceptoras de Vertebrados/efectos de los fármacos , Células Fotorreceptoras de Vertebrados/metabolismo , Células Fotorreceptoras de Vertebrados/patología , Serina C-Palmitoiltransferasa/metabolismo , Serina C-Palmitoiltransferasa/antagonistas & inhibidores , Peróxido de Hidrógeno/toxicidad , Peróxido de Hidrógeno/farmacología , Línea Celular , Degeneración Retiniana/metabolismo , Degeneración Retiniana/prevención & control , Degeneración Retiniana/patología , Degeneración Retiniana/tratamiento farmacológico , Western Blotting , Inhibidores Enzimáticos/farmacología , Supervivencia Celular/efectos de los fármacos
2.
Heliyon ; 10(5): e26972, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38444489

RESUMEN

Due to the influence of structural clearances, the shearer's oscillates and jumps concerning the scraper are frequent, which induces the collision and vibration impact of the traction components and exacerbates the traction failure of the shearer. Therefore, to explore the correlation between attitude disturbance and traction vibration, an experiment on the traction vibration is carried out, the spatial swaying of the shearer and vibration differences between two traction components are obtained, the influence of the lifting angle of the rocker arm is discussed, and the influence mechanism of the shearer attitude disturbance on traction vibration is elucidated. The results indicate that the rolling swing intensity of the shearer is the highest while the yawing swing intensity is the lowest, and the pitch swing intensity increases with the increase of the lifting angle of the rocker arm. Besides, the vibration impact indices of the two walking mechanisms have a competitive relationship of one decreasing but the other increasing, which can be used as a reference signal to judge the rolling swing and load-sharing performance of the traction part. Moreover, with the swing attitude, the competitive relationship of the average of vibration peaks is shown in the two support shoes, and it can be used as a reference signal to judge the pitching swing and the load-sharing performance of the traction part. This result reveals the impact mechanism of attitude disturbances on traction vibration and proposes a signal monitoring approach for judging the traction attitude disturbance and load-sharing performance, providing a reference for reducing traction faults.

3.
Drug Resist Updat ; 73: 101065, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38367548

RESUMEN

AIMS: To investigate the collateral sensitivity (CS) of ABCB1-positive multidrug resistant (MDR) colorectal cancer cells to the survivin inhibitor MX106-4C and the mechanism. METHODS: Biochemical assays (MTT, ATPase, drug accumulation/efflux, Western blot, RT-qPCR, immunofluorescence, flow cytometry) and bioinformatic analyses (mRNA-sequencing, reversed-phase protein array) were performed to investigate the hypersensitivity of ABCB1 overexpressing colorectal cancer cells to MX106-4C and the mechanisms. Synergism assay, long-term selection, and 3D tumor spheroid test were used to evaluate the anti-cancer efficacy of MX106-4C. RESULTS: MX106-4C selectively killed ABCB1-positive colorectal cancer cells, which could be reversed by an ABCB1 inhibitor, knockout of ABCB1, or loss-of-function ABCB1 mutation, indicating an ABCB1 expression and function-dependent mechanism. MX106-4C's selective toxicity was associated with cell cycle arrest and apoptosis through ABCB1-dependent survivin inhibition and activation on caspases-3/7 as well as modulation on p21-CDK4/6-pRb pathway. MX106-4C had good selectivity against ABCB1-positive colorectal cancer cells and retained this in multicellular tumor spheroids. In addition, MX106-4C could exert a synergistic anti-cancer effect with doxorubicin or re-sensitize ABCB1-positive cancer cells to doxorubicin by reducing ABCB1 expression in the cell population via long-term exposure. CONCLUSIONS: MX106-4C selectively kills ABCB1-positive MDR colorectal cancer cells via a novel ABCB1-dependent survivin inhibition mechanism, providing a clue for designing CS compound as an alternative strategy to overcome ABCB1-mediated colorectal cancer MDR.


Asunto(s)
Antineoplásicos , Neoplasias Colorrectales , Humanos , Survivin/genética , Survivin/metabolismo , Survivin/farmacología , Resistencia a Múltiples Medicamentos/genética , Sensibilidad Colateral al uso de Fármacos , Resistencia a Antineoplásicos/genética , Línea Celular Tumoral , Doxorrubicina/farmacología , Doxorrubicina/uso terapéutico , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/metabolismo , Antineoplásicos/uso terapéutico , Subfamilia B de Transportador de Casetes de Unión a ATP/genética , Subfamilia B de Transportador de Casetes de Unión a ATP/farmacología
4.
ACS Omega ; 8(17): 15684-15697, 2023 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-37151513

RESUMEN

In top coal caving mining, the coal rock collapse will cause an irregular impact on the tail beam jack of the caving control mechanism. The severe impact will lead to jack failure. The bidirectional fluid-structure coupling model is built on Fluent and Mechanical software to study the impact response of the tail beam jack. The dynamic flow velocity streamlines, hydraulic pressure distribution, stress field, and strain field of the jack under impact load are extracted. The response characteristics of the jack in the stationary state and motion state are analyzed. The conclusions are as follows: the stress and strain of the rodless cavity are much larger than those of the rod cavity, which is more likely to be damaged. The hydraulic pressure in the jack cavity is in vertical layered distribution. The flow velocity streamlines present spiral shapes. The response degree of the hydraulic pressure signal in the rodless cavity is stronger than that in the rod cavity, and the response degree of the flow velocity signal in the rod cavity is stronger than that in the rodless cavity. The impact response of the jack in the motion state is more sensitive and stronger than that in the stationary state. The coal rock collapse situation can be most effectively identified only by comprehensively analyzing the rodless cavity's pressure signal and the rod cavity's velocity signal. This paper innovatively visualizes the flow velocity streamlines and pressure distribution together. The bidirectional fluid-structure coupling method is innovatively applied to the tail beam jack. The findings of this study can help for better understanding of the tail beam jack's structural design and failure prevention. This study provides a certain research basis for the intelligent coal rock identification technology in mining coal based on jack vibration signals.

5.
Biochem Biophys Rep ; 33: 101408, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36532875

RESUMEN

Despite the availability of combined antiretroviral therapy (cART), which reduces the HIV replication in chronically HIV-infected patients, HIV associated neurocognitive disorders (HAND) persists in the brain. The blood-brain barrier (BBB) is the major barrier for the penetration of drugs including antiretrovirals, limiting the drug penetration to the brain. In the present study, we have shown improved brain drug concentration in mice for darunavir (DRV), an FDA-approved drug, using an intranasal (IN) delivery method that bypasses the BBB. Here, we compared the time-dependent biodistribution of DRV at two different concentrations, high (25 mg/kg) and low (2.5 mg/kg), using two administration routes intravenous (IV) and intranasal (IN) in brain, liver, lungs, and plasma. Compared with IV administration, IN administration demonstrated a significantly improved DRV penetration in the brain at both low and high DRV concentrations (IV vs IN: at 2.5 mg/kg: 6.91 ± 1.69 ng/g vs 12.08 ± 2.91 ng/g, at 25 mg/kg: 12.84 ± 2.88 ng/g vs 19.74 ± 1.80 ng/g). As expected, IN administration showed significantly lower DRV concentrations in plasma (IV vs IN: at 2.5 mg/kg: 81.37 ± 22.04 ng/g vs 19.91 ± 12.65 ng/g, at 25 mg/kg: 899.12 ± 136.93 ng/g vs 320.56 ± 40.04 ng/g) and liver (IV vs IN: at 2.5 mg/kg: 118.39 ± 28.13 ng/g vs 29.27 ± 4.17 ng/g at 25 mg/kg: 1085.18 ± 255.0 ng/g vs 833.83 ± 242.4 ng/g). The IN administration did not show significant change in lungs compared to the IV administration. As a result, these findings suggest that the IN route can increase the DRV level in the brain, suppressing HIV in the brain reservoirs. Additionally, it could also reduce off-target effects, especially in peripheral organs.

6.
Nutr Hosp ; 39(5): 1135-1143, 2022 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-36134592

RESUMEN

Introduction: Introduction: infantile colic has always been a problem for caregivers, and research on probiotics in treating and preventing infant colic is still controversial. Material and methods: trials were performed before November 2021 and retrieved from the PubMed, Web of Science, The Cochrane Library, Medline, and Google Scholar databases. Data extraction and quality evaluation of the trials were performed independently by two investigators. A meta-analysis was performed using Review Manager 5.3. It includes nine randomized controlled trials in 587 infants with colic. Results: eight of these experiments described probiotics for the prevention and treatment of intestinal colic in infants, with 228 in the probiotics group and 227 in the placebo group, with a total effective rate (RR = 1.88, 95 % CI: 1.61 to 2.19, p < 0.00001). Conclusion: probiotics may improve therapeutic and preventive effects, especially within four weeks of probiotic treatment.


Introducción: Introducción: el cólico infantil siempre ha sido un problema para los cuidadores y la investigación sobre los probióticos para tratar y prevenir el cólico infantil sigue siendo controvertida. Material y métodos: los ensayos se realizaron antes de noviembre de 2021 y se recuperaron de las bases de datos PubMed, Web of Science, The Cochrane Library, Medline y Google Scholar. Dos investigadores realizaron de forma independiente la extracción de datos y la evaluación de la calidad de los ensayos. Se realizó un metaanálisis utilizando Review Manager 5.3. Incluye nueve ensayos controlados aleatorios en 587 lactantes con cólicos. Resultados: ocho de estos experimentos describieron probióticos para la prevención y el tratamiento del cólico intestinal en lactantes, con 228 en el grupo de probióticos y 227 en el grupo de placebo, con una tasa efectiva total (RR = 1,88, IC del 95 %: 1,61 a 2,19, p < 0,00001). Conclusión: los probióticos pueden mejorar los efectos terapéuticos y preventivos, especialmente dentro de las cuatro semanas posteriores al tratamiento con los mismos.


Asunto(s)
Cólico , Probióticos , Cólico/tratamiento farmacológico , Humanos , Lactante , Probióticos/uso terapéutico , Ensayos Clínicos Controlados Aleatorios como Asunto
7.
Nutr. hosp ; 39(5): 1135-1143, sep.-oct. 2022. ilus, tab, graf
Artículo en Inglés | IBECS | ID: ibc-213973

RESUMEN

Introduction: infantile colic has always been a problem for caregivers, and research on probiotics in treating and preventing infant colic is still controversial. Material and methods: trials were performed before November 2021 and retrieved from the PubMed, Web of Science, The Cochrane Library, Medline, and Google Scholar databases. Data extraction and quality evaluation of the trials were performed independently by two investigators. A meta-analysis was performed using Review Manager 5.3. It includes nine randomized controlled trials in 587 infants with colic. Results: eight of these experiments described probiotics for the prevention and treatment of intestinal colic in infants, with 228 in the probiotics group and 227 in the placebo group, with a total effective rate (RR = 1.88, 95 % CI: 1.61 to 2.19, p < 0.00001). Conclusion: probiotics may improve therapeutic and preventive effects, especially within four weeks of probiotic treatment. (AU)


Introducción: el cólico infantil siempre ha sido un problema para los cuidadores y la investigación sobre los probióticos para tratar y prevenir el cólico infantil sigue siendo controvertida. Material y métodos: los ensayos se realizaron antes de noviembre de 2021 y se recuperaron de las bases de datos PubMed, Web of Science, The Cochrane Library, Medline y Google Scholar. Dos investigadores realizaron de forma independiente la extracción de datos y la evaluación de la calidad de los ensayos. Se realizó un metaanálisis utilizando Review Manager 5.3. Incluye nueve ensayos controlados aleatorios en 587 lactantes con cólicos. Resultados: ocho de estos experimentos describieron probióticos para la prevención y el tratamiento del cólico intestinal en lactantes, con 228 en el grupo de probióticos y 227 en el grupo de placebo, con una tasa efectiva total (RR = 1,88, IC del 95 %: 1,61 a 2,19, p < 0,00001). Conclusión: los probióticos pueden mejorar los efectos terapéuticos y preventivos, especialmente dentro de las cuatro semanas posteriores al tratamiento con los mismos. (AU)


Asunto(s)
Humanos , Masculino , Femenino , Niño , Cólico/tratamiento farmacológico , Probióticos/uso terapéutico , Ensayos Clínicos Controlados Aleatorios como Asunto , Placebos
8.
Bioorg Med Chem ; 68: 116876, 2022 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-35716586

RESUMEN

Large conductance, calcium/voltage-gated potassium channels (BK) regulate critical body processes, including neuronal, secretory and smooth muscle (SM) function. While BK-forming alpha subunits are ubiquitous, accessory beta1 subunits are highly expressed in SM. This makes beta1 an attractive target for pharmaceutical development to treat SM disorders, such as hypertension or cerebrovascular spasm. Compounds activating BK via beta1 have been identified, yet they exhibit low potency and off-target effects while antagonists that limit agonist activity via beta 1 remain unexplored. Beta1-dependent BK ligand-based pharmacophore modeling and ZINC database searches identified 15 commercially available hits. Concentration-response curves on BK alpha + beta1 subunit-mediated currents were obtained in CHO cells. One potent (EC50 = 20 nM) and highly efficacious activator (maximal activation = ×10.3 of control) was identified along with a potent antagonist (KB = 3.02 nM), both of which were dependent on beta1. Our study provides the first proof-of-principle that an agonist/antagonist pair can be used to control beta1-containing BK activity.


Asunto(s)
Calcio , Subunidades beta de los Canales de Potasio de Gran Conductancia Activados por el Calcio , Animales , Calcio/metabolismo , Cricetinae , Cricetulus , Canales de Potasio de Gran Conductancia Activados por el Calcio , Técnicas de Placa-Clamp
9.
PLoS One ; 17(6): e0269865, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35687602

RESUMEN

To study the influence of the gangue content of coal gangue particles on the vibration signal of the tail beam under sliding condition, this paper combines three-dimensional(3D) laser scanning technology with the finite element method, establishes a finite element model of the real shape of coal gangue particles and the hydraulic support in top coal caving in LS-DYNA, analyzes the influence of gangue content on some characteristics of the acceleration signal on the tail beam in the time and frequency domains, and then studies the influence of the size and total mass of the rock, and the angle of the tail beam on the characteristics. The following conclusions are obtained: when the coal gangue particles slip on the tail beam, an increase in gangue content significantly improves the effective value of the acceleration signal of the tail beam in the time domain and the average power and average amplitude in the frequency domain. With different sizes, total masses, and tail beam angles, the increase in gangue content always causes an increase in acceleration signal characteristics. In terms of the influence of various factors on the same gangue content, at the same total mass, the larger the rock mass size is, the faster the characteristic value increases with the increase in gangue content. The greater the total mass, the greater the value of the acceleration signal characteristics. A smaller angle between the tail beam and the ground increases the value of each characteristic. The results of this study provide a reference for further research on coal gangue identification based on vibrations.


Asunto(s)
Carbón Mineral , Vibración
10.
Mol Cancer Ther ; 21(7): 1103-1114, 2022 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-35499388

RESUMEN

Triple-negative breast cancer (TNBC) is a highly aggressive type of breast cancer. Unlike other subtypes of breast cancer, TNBC lacks hormone and growth factor receptor targets. Colchicine-binding site inhibitors (CBSI) targeting tubulin have been recognized as attractive agents for cancer therapy, but there are no CBSI drugs currently FDA approved. CH-2-77 has been reported to have potent antiproliferative activity against a panel of cancer cells in vitro and efficacious antitumor effects on melanoma xenografts, yet, its anticancer activity specifically against TNBC is unknown. Herein, we demonstrate that CH-2-77 inhibits the proliferation of both paclitaxel-sensitive and paclitaxel-resistant TNBC cells with an average IC50 of 3 nmol/L. CH-2-77 also efficiently disrupts the microtubule assembly, inhibits the migration and invasion of TNBC cells, and induces G2-M cell-cycle arrest. The increased number of apoptotic cells and the pattern of expression of apoptosis-related proteins in treated MDA-MB-231 cells suggest that CH-2-77 induces cell apoptosis through the intrinsic apoptotic pathway. In vivo, CH-2-77 shows acceptable overall pharmacokinetics and strongly suppresses the growth of orthotopic MDA-MB-231 xenografts without gross cumulative toxicities when administered 5 times a week. The in vivo efficacy of CH-2-77 (20 mg/kg) is comparable with that of CA4P (28 mg/kg), a CBSI that went through clinical trials. Importantly, CH-2-77 prevents lung metastasis originating from the mammary fat pad in a dose-dependent manner. Our data demonstrate that CH-2-77 is a promising new generation of tubulin inhibitors that inhibit the growth and metastasis of TNBC, and it is worthy of further development as an anticancer agent.


Asunto(s)
Neoplasias de la Mama Triple Negativas , Apoptosis , Sitios de Unión , Línea Celular Tumoral , Proliferación Celular , Colchicina/farmacología , Colchicina/uso terapéutico , Humanos , Paclitaxel/farmacología , Neoplasias de la Mama Triple Negativas/patología , Tubulina (Proteína)/metabolismo , Moduladores de Tubulina/farmacología , Moduladores de Tubulina/uso terapéutico
11.
ACS Omega ; 7(4): 3656-3670, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-35128274

RESUMEN

The existing research on coal gangue identification based on vibration usually assumes that coal gangue particles are ideal shapes. To understand the vibration response difference in hydraulic support caused by coal and gangue with real shapes, this paper uses a three-dimensional (3D) scanning technology to determine the real shape of coal particles. The process of coal and gangue impacting the tail beam at different angles was simulated in the LS-DYNA software package, and the effects of shape parameters, velocity, and coal strength on the difference in vibration signals caused by the two were analyzed statistically. The conclusions are as follows: the vibrational response of the tail beam is concentrated mainly in the area between the ribs. The regularity of the velocity signal caused by gangue is better than the regularity of the velocity signal caused by coal, and the attenuation speed of the acceleration signal of gangue is slower than the attenuation speed of the acceleration signal of coal. The probability distributions of the velocity and acceleration responses were analyzed statistically, and the results show that the results from coal can be well fitted by a logarithmic normal function, and the standard deviations of velocity and acceleration are 0.05591 and 489.8, respectively. The gangue results are fitted by the gamma function and the Weibull function, and the standard deviations are 0.13531 and 737.9, respectively, showing that the fitting function has the potential to be used as the basis for coal gangue identification. The change in coal strength has little effect on the vibration response of the tail beam. With increasingly falling velocity, the vibration signal intensity of the tail beam increases, but the discrimination between coal and gangue weakens; therefore, measures should be taken to reduce the falling velocity of the rock mass. The research results of this paper can provide a reference for further study of coal gangue identification methods based on vibration.

12.
J Med Chem ; 64(16): 12049-12074, 2021 08 26.
Artículo en Inglés | MEDLINE | ID: mdl-34378386

RESUMEN

We previously reported a potent tubulin inhibitor CH-2-77. In this study, we optimized the structure of CH-2-77 by blocking metabolically labile sites and synthesized a series of CH-2-77 analogues. Two compounds, 40a and 60c, preserved the potency while improving the metabolic stability over CH-2-77 by 3- to 4-fold (46.8 and 29.4 vs 10.8 min in human microsomes). We determined the high-resolution X-ray crystal structures of 40a (resolution 2.3 Å) and 60c (resolution 2.6 Å) in complex with tubulin and confirmed their direct binding at the colchicine-binding site. In vitro, 60c maintained its mode of action by inhibiting tubulin polymerization and was effective against P-glycoprotein-mediated multiple drug resistance and taxol resistance. In vivo, 60c exhibited a strong inhibitory effect on tumor growth and metastasis in a taxol-resistant A375/TxR xenograft model without obvious toxicity. Collectively, this work showed that 60c is a promising lead compound for further development as a potential anticancer agent.


Asunto(s)
Antineoplásicos/uso terapéutico , Neoplasias/tratamiento farmacológico , Piridinas/uso terapéutico , Moduladores de Tubulina/uso terapéutico , Tubulina (Proteína)/metabolismo , Animales , Antineoplásicos/síntesis química , Antineoplásicos/metabolismo , Antineoplásicos/farmacocinética , Sitios de Unión , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Diseño de Fármacos , Ensayos de Selección de Medicamentos Antitumorales , Estabilidad de Medicamentos , Femenino , Puntos de Control de la Fase G2 del Ciclo Celular/efectos de los fármacos , Humanos , Masculino , Ratones Endogámicos NOD , Ratones SCID , Microsomas Hepáticos/metabolismo , Estructura Molecular , Metástasis de la Neoplasia/prevención & control , Piridinas/síntesis química , Piridinas/metabolismo , Piridinas/farmacocinética , Relación Estructura-Actividad , Tubulina (Proteína)/química , Moduladores de Tubulina/síntesis química , Moduladores de Tubulina/metabolismo , Moduladores de Tubulina/farmacocinética , Ensayos Antitumor por Modelo de Xenoinjerto
13.
Oncol Lett ; 19(5): 3558-3566, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32269630

RESUMEN

Metastasis remains a notable issue in patients with newly diagnosed colorectal carcinomas (CRC). Although anti-angiogenic therapies target metastatic diseases, hypoxia-inducible factor-1 α (HIF-1α) and vascular endothelial growth factor (VEGF) status are routinely evaluated in primary tumors as metastatic sites are infrequently biopsied. The present study aimed to investigate the expression and significance of HIF-1α, VEGF and microvascular density (MVD) in primary tumors and corresponding metastatic CRC tissues. HIF-1α, VEGF and CD34 status were analyzed via immunohistochemistry analysis in 46 patients who underwent surgical resection of primary CRC (35 colon and 11 rectum) and matched metastases (lymph node and liver metastases) in Shandong Cancer Hospital. The association between selected biomarker status and clinicopathological characteristics was analyzed, and expression levels in primary tumors and corresponding metastases were compared. A total of 46 paired colorectal primary tumor and synchronous metastases samples were acquired for analysis using a standardized HIF-1α, VEGF and CD34 immunohistochemical procedure. The results demonstrated that the positive rates of HIF-1α and VEGF in primary CRC were 70 and 73.9%, respectively. HIF-1α (60.9%) and VEGF (58.7%) expression decreased in the lymph metastatic samples compared with primary CRC. Conversely, the level of MVD in primary tumors was significantly higher compared with metastatic tumors. No significant differences were demonstrated between HIF-1α and VEGF expression and the different clinicopathological features in primary CRC and corresponding metastases. Primary carcinomas and matched metastatic tissues demonstrated a moderate level of consistent immunoreactivity for HIF-1α and VEGF. HIF-1α, VEGF and CD34 were expressed in both primary tumors and corresponding metastases of CRC, suggesting that they may be involved in the development of metastasis. HIF-1α and VEGF expression in primary sites was consistent with that observed in metastases; however, it varied from that exhibited in MVD. The current analysis will improve the current understanding of the metastasis models and provide further evidence for evaluating the response to HIF-1α and VEGF inhibitors.

14.
Front Cell Dev Biol ; 8: 604869, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33520987

RESUMEN

OBJECTIVES: Colon cancer (CC) currently ranks as the third most common human cancer worldwide with an increasing incidence and a poor prognosis. Recently, circular RNAs have been reported to regulate the progression of diverse human cancers. However, the role of circRNA hsa_circ_0020095 in CC remains largely unclear. METHODS: Expression levels of the related circRNAs, microRNAs and mRNA in CC tissues and cells were determined. The impacts of circ_0020095 or miR-487a-3p on CC cells were examined at the indicated times after transfection. Meanwhile, a luciferase-reporter experiment was employed to validate the interplay between miR-487a-3p and circ_002009695 or SOX9. Moreover, the in vivo tumor growth assay was applied to further evaluate the effects of circ_0020095 knockdown on CC progression. RESULTS: We demonstrated that circ_0020095 was highly expressed in CC tissues and cells. The proliferation, migration, invasion, and cisplatin resistance of CC were suppressed by silencing circ_0020095 in vitro and in vivo or by ectopic expression of miR-487a-3p in vitro. Mechanistically, circ_0020095 could directly bind to miR-487a-3p and subsequently act as a miR-487a-3p sponge to modulate the activity by targeting the 3'-UTR of SOX9. Interestingly, overexpression of circ_0020095 dramatically reversed the suppressive effects of miR-487a-3p mimics on CC cells. CONCLUSION: Circ_0020095 functions as an oncogene to accelerate CC cell proliferation, invasion, migration and cisplatin resistance through the miR-487a-3p/SOX9 axis, which could be a promising target for CC treatment.

15.
J Med Chem ; 63(2): 827-846, 2020 01 23.
Artículo en Inglés | MEDLINE | ID: mdl-31860298

RESUMEN

We recently reported the crystal structure of tubulin in complex with a colchicine binding site inhibitor (CBSI), ABI-231, having 2-aryl-4-benzoyl-imidazole (ABI). Based on this and additional crystal structures, here we report the structure-activity relationship study of a novel series of pyridine analogues of ABI-231, with compound 4v being the most potent one (average IC50 ∼ 1.8 nM) against a panel of cancer cell lines. We determined the crystal structures of another potent CBSI ABI-274 and 4v in complex with tubulin and confirmed their direct binding at the colchicine site. 4v inhibited tubulin polymerization, strongly suppressed A375 melanoma tumor growth, induced tumor necrosis, disrupted tumor angiogenesis, and led to tumor cell apoptosis in vivo. Collectively, these studies suggest that 4v represents a promising new generation of tubulin inhibitors.


Asunto(s)
Antineoplásicos/síntesis química , Antineoplásicos/farmacología , Proliferación Celular/efectos de los fármacos , Piridinas/síntesis química , Piridinas/farmacología , Moduladores de Tubulina/síntesis química , Moduladores de Tubulina/farmacología , Inhibidores de la Angiogénesis/síntesis química , Inhibidores de la Angiogénesis/farmacología , Apoptosis/efectos de los fármacos , Neoplasias de la Mama/tratamiento farmacológico , Línea Celular Tumoral , Colchicina/química , Cristalografía por Rayos X , Resistencia a Antineoplásicos/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Humanos , Modelos Moleculares , Relación Estructura-Actividad
16.
J Med Chem ; 62(14): 6734-6750, 2019 07 25.
Artículo en Inglés | MEDLINE | ID: mdl-31251599

RESUMEN

ABI-231 is a potent, orally bioavailable tubulin inhibitor that interacts with the colchicine binding site and is currently undergoing clinical trials for prostate cancer. Guided by the crystal structure of ABI-231 in complex with tubulin, we performed structure-activity relationship studies around the 3-indole moiety that led to the discovery of several potent ABI-231 analogues, most notably 10ab and 10bb. The crystal structures of 10ab and 10bb in complex with tubulin confirmed their improved molecular interactions to the colchicine site. In vitro, biological studies showed that new ABI-231 analogues disrupt tubulin polymerization, promote microtubule fragmentation, and inhibit cancer cell migration. In vivo, analogue 10bb not only significantly inhibits primary tumor growth and decreases tumor metastasis in melanoma xenograft models but also shows a significant ability to overcome paclitaxel resistance in a taxane-resistant PC-3/TxR model. In addition, pharmacological screening suggested that 10bb has a low risk of potential off-target function.


Asunto(s)
Imidazoles/química , Imidazoles/farmacología , Moduladores de Tubulina/química , Moduladores de Tubulina/farmacología , Tubulina (Proteína)/metabolismo , Animales , Sitios de Unión/efectos de los fármacos , Colchicina/metabolismo , Cristalografía por Rayos X , Diseño de Fármacos , Humanos , Imidazoles/síntesis química , Indoles/síntesis química , Indoles/química , Indoles/farmacología , Simulación del Acoplamiento Molecular , Tubulina (Proteína)/química , Moduladores de Tubulina/síntesis química
17.
Mol Pharmacol ; 96(1): 73-89, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31043459

RESUMEN

Interfering with microtubule dynamics is a well-established strategy in cancer treatment; however, many microtubule-targeting agents are associated with drug resistance and adverse effects. Substantial evidence points to ATP-binding cassette (ABC) transporters as critical players in the development of resistance. Herein, we demonstrate the efficacy of DJ95 (2-(1H-indol-6-yl)-4-(3,4,5-trimethoxyphenyl)-1H-imidazo[4,5-c]pyridine), a novel tubulin inhibitor, in a variety of cancer cell lines, including malignant melanomas, drug-selected resistant cell lines, specific ABC transporter-overexpressing cell lines, and the National Cancer Institute 60 cell line panel. DJ95 treatment inhibited cancer cell migration, caused morphologic changes to the microtubule network foundation, and severely disrupted mitotic spindle formation of mitotic cells. The high-resolution crystal structure of DJ95 in complex with tubulin protein and the detailed molecular interactions confirmed its direct binding to the colchicine site. In vitro pharmacological screening of DJ95 using SafetyScreen44 (Eurofins Cerep-Panlabs) revealed no significant off-target interactions, and pharmacokinetic analysis showed that DJ95 was maintained at therapeutically relevant plasma concentrations for up to 24 hours in mice. In an A375 xenograft model in nude mice, DJ95 inhibited tumor growth and disrupted tumor vasculature in xenograft tumors. These results demonstrate that DJ95 is potent against a variety of cell lines, demonstrated greater potency to ABC transporter-overexpressing cell lines than existing tubulin inhibitors, directly targets the colchicine binding domain, exhibits significant antitumor efficacy, and demonstrates vascular-disrupting properties. Collectively, these data suggest that DJ95 has great potential as a cancer therapeutic, particularly for multidrug resistance phenotypes, and warrants further development. SIGNIFICANCE STATEMENT: Paclitaxel is a widely used tubulin inhibitor for cancer therapy, but its clinical efficacy is often limited by the development of multidrug resistance. In this study, we reported the preclinical characterization of a new tubulin inhibitor DJ95, and demonstrated its abilities to overcome paclitaxel resistance, disrupt tumor vasculature, and exhibit significant antitumor efficacy.


Asunto(s)
Resistencia a Antineoplásicos/efectos de los fármacos , Melanoma/tratamiento farmacológico , Bibliotecas de Moléculas Pequeñas/administración & dosificación , Moduladores de Tubulina/administración & dosificación , Tubulina (Proteína)/química , Transportadoras de Casetes de Unión a ATP/metabolismo , Animales , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Colchicina/metabolismo , Cristalografía por Rayos X , Femenino , Células HEK293 , Células Endoteliales de la Vena Umbilical Humana , Humanos , Imidazoles/administración & dosificación , Imidazoles/química , Imidazoles/farmacología , Masculino , Melanoma/metabolismo , Ratones , Ratones Desnudos , Piridinas/administración & dosificación , Piridinas/química , Piridinas/farmacología , Bibliotecas de Moléculas Pequeñas/química , Bibliotecas de Moléculas Pequeñas/farmacología , Tubulina (Proteína)/metabolismo , Moduladores de Tubulina/química , Moduladores de Tubulina/farmacología , Ensayos Antitumor por Modelo de Xenoinjerto
18.
Pharm Dev Technol ; 24(8): 1038-1043, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31134840

RESUMEN

Background: Clindamycin's bitter taste and odor is known to affect treatment adherence in children. Recently, a formulation of clindamycin HCl complexed with ion exchange resin IRP 69 was shown to mask the bitter taste. Because of the potential benefit of this formulation for children, a pilot study using a porcine model was conducted to evaluate its relative bioavailability. Methods: A randomized two-way crossover study design using six (n = 6) healthy male piglets 10-12 kg was used to evaluate the absorption profiles and pharmacokinetic parameters of clindamycin from the resinate complex formulation (Test) compared to a commercialized reference suspension. A dose of 15 mg/kg was administered orally by gastric gavage to each piglet followed by repeated blood sampling over 12 h. A wash-out period of 48 h occurred between treatments. Plasma concentration vs. time data was analyzed by non-compartmental analysis. Results: The mean relative bioavailability of clindamycin from the resinate formulation was 78.8%. A two-tailed, paired Student t test yielded a p < 0.05 for AUC∞ and Tmax parameters. A two one-sided test (TOST) suggested a difference in AUC∞ and Cmax for the Test formulation compared to the reference formulation according to the FDA's criteria for bioequivalence. Conclusion: The bioavailability of clindamycin from this novel oral formulation supports continued evaluation of the drug in humans for potential pediatric applications.


Asunto(s)
Clindamicina/farmacocinética , Resinas de Intercambio Iónico/farmacocinética , Suspensiones/farmacocinética , Gusto/efectos de los fármacos , Administración Oral , Animales , Antibacterianos/farmacocinética , Área Bajo la Curva , Disponibilidad Biológica , Química Farmacéutica/métodos , Estudios Cruzados , Semivida , Masculino , Proyectos Piloto , Porcinos , Equivalencia Terapéutica
19.
Transl Cancer Res ; 8(6): 2284-2294, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35116981

RESUMEN

BACKGROUND: Patients receiving radiotherapy and chemotherapy have a high risk developing to an acute chemoradiotherapy-induced diarrhea (RID). The clinical efficacy of octreotide in controlling chemoradiotherapy-induced diarrhea remains controversial. We performed a meta-analysis of randomized controlled trials (RCTs) to evaluate the efficacy of octreotide for treatment the chemoradiotherapy-induced diarrhoea. METHODS: Relevant RCTs studies assessing the effect of octreotide on clinical outcomes compared with placebo were searched in Cochrane Library, PubMed, EMBASE and Web of Science (up to December 2018). Heterogeneity was assessed with I2, and publication bias was evaluated using sensitive analysis. RESULTS: Eight trials, a total of 594 participants. We found octreotide was significantly effective compared with the control group (OR =3.17; 95% CI, 1.28-7.85; P<0.0001). The overall effect of octreotide was 62.5% (220/352), while that of the control group was 49.3% (168/341). We found octreotide group was effective compared with the control group in 24, 48, and 96 h (OR =16.02; 95% CI, 3.51-73.15; P=0.0003), (OR =4.70; 95% CI, 1.65-13.42; P=0.004) and (OR =14.49; 95% CI, 6.24-33.65; P<0.00001). CONCLUSIONS: Octreotide is superior to conventional therapy in the duration and effectiveness for chemoradiotherapy-induced diarrhea.

20.
Onco Targets Ther ; 11: 8987-8993, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30588011

RESUMEN

Familial adenomatous polyposis (FAP) is a rare autosomal dominant genetic disease related to germline mutations of the APC gene. The clinical features of this disease most commonly include hundreds of adenomas or polyps. If not treated in a timely fashion, FAP can eventually result in colorectal carcinoma. In this report, clinical manifestations, family history, relevant auxiliary examinations and gene detection from patient blood led us to discover a novel frameshift mutation in exon 12 of the APC gene. The deletion of adenine in c.1439 resulted in the formation of codon 480. The occurrence of this frameshift deletion may lead to inexpressibility of the main functional regions in APC and may affect gene function. In addition, colonoscopy and histopathology showed malignant changes in the colon and rectum. There have been no reports of this frameshift mutation, but it can be considered in case of APC mutations and FAP in patients with clinical manifestations; auxiliary examination may be related, and it may be used as a reference for preventive clinical treatment in the future.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...