RESUMEN
Ultraviolet (UV)/chlorine draws increasing attention for the abatement of recalcitrant organic pollutants. Herein, it was found that TiO2 would significantly promote the degradation of dimethyl phthalate (DMP) in the UV/chlorine system (from 19 to 84%). Hydroxyl radicals (HOâ¢) and chlorine radicals (Clâ¢) were the dominant reactive species for DMP degradation in the UV/chlorine/TiO2 system. Chlorine decayed much faster in UV/chlorine/TiO2 compared with UV/chlorine, which is possibly because photogenerated electrons (ecb-) and superoxide radicals (O2â¢-) have high reactivity with chlorine. As a result, the recombination of photogenerated holes (hvb+) and ecb- was inhibited and the accumulation of HO⢠and Cl⢠was facilitated. A kinetic model was established to simulate the reaction process, and it was found that the concentrations of HO⢠and Cl⢠were several times to dozens of times higher in UV/chlorine/TiO2 than that in UV/chlorine. The contributions of HO⢠and Cl⢠to DMP degradation were 70.3 and 29.7% by model simulation, respectively, and were close to the probe experiment result. In the UV/chlorine/TiO2 system, the degradation of DMP did not follow pseudo-first-order kinetics but the degradation of benzoate fitted well with pseudo-first-order kinetics. This phenomenon was elucidated by the structure of the pollutant and TiO2 and further tested by calculating the adsorption energy (Eads)/binding energy (Eb) with density functional theory. Due to faster decay of chlorine, lower amounts of disinfection byproducts formed in UV/chlorine/TiO2 compared with UV/chlorine. Adding TiO2 into the UV/chlorine system can promote the degradation of recalcitrant organic pollutants in an aqueous environment.
Asunto(s)
Contaminantes Químicos del Agua , Purificación del Agua , Cloro , Cinética , Oxidación-Reducción , Titanio , Rayos Ultravioleta , Contaminantes Químicos del Agua/análisisRESUMEN
PM2.5 (aerodynamic diameter ≤2.5 µm) has been a dominating and ubiquitous air pollutant and has become a global concern. Emerging evidences suggest a positive correlation between PM2.5 and leukemia, but the underlying molecular mechanisms remain unclear and need to be elucidated. Here, we assessed the impacts of PM2.5 on the progression and inflammation of human myeloid leukemia at lower environmental doses and explored the possible pathway. We showed that PM2.5 exposure significantly induced the leukemia cell growth and enhanced the release of inflammatory mediators in both in vitro and in vivo models. Additionally, NF-κB p65 and p-STAT3 were activated in PM2.5-treated leukemia cells, with a concomitant increase in both ROS formation and NADPH oxidase expressions. Strikingly, the supplement of inhibitors, including NAC (ROS), PDTC (NF-κB), or WP1066 (STAT3), contributed to a decline in leukemia cell growth. Furthermore, enhanced expressions of inflammatory cytokines were attenuated by the addition of NAC or PDTC, but not affected by WP1066. This study demonstrates that PM2.5 promotes leukemia progression, identifies a potential intervention target, and provides further understanding of the detrimental effect of PM2.5 exposure on human health.
Asunto(s)
Contaminantes Atmosféricos/toxicidad , Proliferación Celular/efectos de los fármacos , Citocinas/metabolismo , Leucemia Experimental/inmunología , Leucemia Mieloide/inmunología , Material Particulado/toxicidad , Animales , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/inmunología , Progresión de la Enfermedad , Relación Dosis-Respuesta a Droga , Células HL-60 , Humanos , Células K562 , Leucemia Experimental/patología , Leucemia Mieloide/patología , Ratones Desnudos , Trasplante de Neoplasias , Especies Reactivas de Oxígeno/metabolismo , Factor de Transcripción STAT3/metabolismo , Factor de Transcripción ReIA/metabolismoRESUMEN
Information storage and anti-counterfeiting are two very important applications of photochromic materials. Photochromic materials with both information storage and anti-counterfeiting should meet the requirements including fast coloration, good stability and reversibility, low storage cost, and practical application value. Herein, a novel viologen-based coordination polymer, Cd[(pbpy)0.5(HBTC)Cl]·2H2O (1) (pbpy = 1,1'-[1,4-phenylenebis-(methylene)]bis(4,4'-bipyridinium); HBTC2- = 1,3,5-benzenetricarboxylic acid), has been constructed. Compound 1 not only exhibits selective amine sensing properties, but also shows excellent photochromic properties, and the anti-counterfeiting of a two-dimensional code can be also realized through the color-changing behavior. Meanwhile, photochromic glass films of compound 1 were prepared, and compared to traditional optical information storage technology, these photochromic glass films have better water resistance and stability, improving their practical application stability. This work has further enriched the application of photochromic materials in the field of sensing, anti-counterfeiting and information storage.
RESUMEN
Colorectal cancer has high morbidity and mortality worldwide, especially in western countries; the incidence of colorectal cancer has been high, which is closely related to the high intake of red meat; and the N-glycolylneuraminic acid (Neu5Gc) is responsible for red meat-induced colorectal cancer. A large number of previous studies have suggested that exogenous Neu5Gc-activated inflammation induced the occurrence of colorectal cancer. However, it has not been known whether the Neu5Gc has a direct inducing effect on colorectal cancer. In this study, we found that Neu5Gc promoted the proliferation of colorectal cancer cells and normal intestinal epithelial cells, and further screened out 98 Neu5Gc targets related to the occurrence and development of colorectal cancer by network pharmacology. Subsequently, GO and KEGG enrichment analyses of these targets revealed that mainly enriched in the PI3K-Akt signaling pathway. Then, we selected SRC, HRAS, CDK2, CCNA2, and AKT2 as core targets based on the phenomena of the previous experiments and the available literature reports, and then we used AutoDock for molecular docking with Neu5Gc; the results found that these five genes could bind to Neu5Gc stably. In vitro experiments showed that the mRNA levels of SRC, HRAS, AKT2, CDK2, and CCNA2 were upregulated and the protein levels of HRAS, AKT2, and CCNA2 were enhanced in FHC and SW620 cells after Neu5Gc (100 ng/mL) treatment. In conclusion, this study revealed that Neu5Gc probably acted as a carcinogen that stimulates the expression of proto-oncogene HRAS and the PI3K-Akt pathway and accelerated cell cycle progression. These findings revealed a novel mechanism that Neu5Gc promoted the occurrence and development of colorectal cancer.
Asunto(s)
Neoplasias Colorrectales , Farmacología en Red , Humanos , Simulación del Acoplamiento Molecular , Fosfatidilinositol 3-Quinasas/genética , Proteínas Proto-Oncogénicas c-akt , Neoplasias Colorrectales/genéticaRESUMEN
Foxtail millet is a traditional excellent crop with high nutritional value in the world, belong to cereals. The bran of foxtail millet is rich in polyphenol that has antioxidant, anti-inflammatory, and anti-tumorigenic effects. Previously, we extracted bound polyphenols from the inner shell of foxtail millet bran (BPIS). Here, we report that BPIS specifically induced breast cancer cell death and elevated the autophagy level simultaneously. The addition of an autophagy inhibitor blocked BPIS-induced breast cancer cell death, indicating that excessive autophagy induced cell death. Furthermore, oil red O and BODIPY staining also confirmed that lipids, which are important inducers of autophagy, accumulated in breast cancer cells treated with BPIS. Lipidomics research revealed that glycerophospholipids were the main accumulated lipids induced by BPIS. Further study showed that elevated PCYT1A expression was responsible for glycerophospholipid accumulation, and BPIS contained ferulic acid and p-coumaric acid, which induced PCYT1A expression and breast cancer cell death. Collectively, our results revealed that BPIS resulted in autophagic death by enhancing lipid accumulation in breast cancer cells, and BPIS contains ferulic acid and p-coumaric acid, which provided new insights into developing nutraceuticals and drugs for breast cancer patients.
Asunto(s)
Neoplasias de la Mama , Setaria (Planta) , Humanos , Femenino , Neoplasias de la Mama/tratamiento farmacológico , Setaria (Planta)/metabolismo , Polifenoles/farmacología , Polifenoles/metabolismo , LípidosRESUMEN
Two genes, MGFc (40) and MGFc (24), encoding different E peptides of mechano-growth factor (MGF), were obtained by a four-step PCR strategy and subcloned into pRSETC and pGEX-6p-1. Recombinant MGFc(40) protein (4 mg l(-1)) was expressed and purified by affinity chromatography using His60 Ni Superflow. Recombinant MGFc(24) protein was purified using a glutathione-Sepharose 4B column. After enzymatic cleavage of the GST-tail, 1 mg MGFc(24) protein l(-1) was obtained. MGFc(40) and MGFc(24), which are involved in proliferation and differentiation, stimulated cell proliferation and inhibited cell differentiation of C2C12 cells.
Asunto(s)
Escherichia coli/genética , Escherichia coli/metabolismo , Factor I del Crecimiento Similar a la Insulina/biosíntesis , Factor I del Crecimiento Similar a la Insulina/aislamiento & purificación , Animales , Línea Celular , Proliferación Celular/efectos de los fármacos , Cromatografía de Afinidad , Clonación Molecular , Expresión Génica , Factor I del Crecimiento Similar a la Insulina/genética , Factor I del Crecimiento Similar a la Insulina/farmacología , Ratones , Proteínas Recombinantes/genética , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismoRESUMEN
Hydroxylamine (NH2OH) has been verified to efficiently strengthen pollutants oxidation in Fe(II)/peroxydisulfate (PDS) and Fe(II)/H2O2 systems. However, the different effects of hydroxylamine salts types were rarely recognized. Herein, the effects of two commonly used hydroxylamine salts (i.e. NH2OH·HCl and (NH2OH)2·H2SO4) on oxidation kinetics and reactive species composition were compared in Fe(II)/PDS and Fe(II)/H2O2 systems for the first time. Pseudo first order kinetics could only describe benzoic acid (BA) oxidation well in Fe(II)/NH2OH/H2O2 system, which was related to the different concentration changes of Fe(III) determined by [Formula: see text] . Hydroxylamine salts types influenced not kinetic rules, but reaction rates of target compounds. The empirical reaction rate constant of BA in Fe(II)/NH2OH·HCl/PDS system was 141.5% of that in Fe(II)/(NH2OH)2·H2SO4/PDS system under the same concentration of NH2OH (1.4 mM), while the apparent reaction rate constant in Fe(II)/NH2OH·HCl/H2O2 system was 68% of that in Fe(II)/(NH2OH)2·H2SO4/H2O2 system. This opposite effect resulted from the differences in primary reactive species compositions and their interactions with Cl-. Reactive species identification indicated that Cl- would decrease the contribution of ferryl ion (Fe(IV)) and transform sulfate radical (SO4·-) to hydroxyl radical (·OH) in Fe(II)/NH2OH/PDS system, while it competitively consumed the only reactive species ·OH in Fe(II)/NH2OH/H2O2 system. This study highlights the importance of reductants types on strengthening Fenton oxidation and offers a reference for reasonable construction of the relevant systems.
Asunto(s)
Compuestos Férricos , Peróxido de Hidrógeno , Compuestos Ferrosos , Hidroxilamina , Hidroxilaminas , Oxidación-Reducción , Sales (Química)RESUMEN
Bone marrow-derived mesenchymal stem cells (MSCs) have emerged as attractive candidates for cellular therapies for heart and other organ-system disorders. However, a major dilemma in stem cell therapy for ischemic heart diseases is the low survival of transplanted cells in the ischemic and peri-infarcted region. In this study, MSCs were treated by hypoxia and serum deprivation (H/SD) to mimic the ischemic microenvironment of infarcted hearts where MSCs were transplanted. The effects of proteasome inhibitor MG-132 on H/SD-induced apoptosis and paracrine effects were investigated. Apoptosis of MSCs was detected by Annexin V-FITC flow cytometric analysis. Transcriptional levels of IL-1ß, TNF-α and IL-10 were examined by real-time PCR. The nuclear translocation of NF-κBp65 was assessed by immunocytochemical staining. Translational changes of IL-1ß and TNF-α were detected by Western blot. The secretion of IL-10 from MSCs was examined by ELISA assay. The results showed that MG-132 could effectively suppress H/SD-induced MSCs apoptosis. Furthermore, the induced IL-1ß and TNF-α transcription was also inhibited by MG-132 treatment, which may be due to the inhibition of NF-κBp65 nuclear translocation by MG-132. Importantly, MG-132 effectively enhanced H/SD-induced transcription and secretion of IL-10, which is an important paracrine factor from MSCs. Our findings suggest that pretreatment of MSCs by MG-132 before cell transplantation may be an effective strategy to improve cell survival and enhance paracrine effects of MSCs.
Asunto(s)
Apoptosis/efectos de los fármacos , Interleucina-10/metabolismo , Leupeptinas/farmacología , Células Madre Mesenquimatosas/citología , Animales , Células de la Médula Ósea/citología , Hipoxia de la Célula , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Medio de Cultivo Libre de Suero , Inhibidores de Cisteína Proteinasa/farmacología , Femenino , Masculino , Ratas , Ratas Sprague-DawleyRESUMEN
Autotaxin (ATX), a member of nucleotide pyrophosphatase/phosphodiesterase (NPP) family, is also named as phosphodiesterase Iα (PD-Iα) or NPP2. ATX is the unique member among the NPPs that can function as a lysophospholipase D (lysoPLD), converting lysophosphatidylcholine into lysophosphatidic acid (LPA). LPA acts on specific G-protein-coupled receptors to elicit a wide range of cellular response, including cell proliferation, cell migration and cell contraction, etc. As the major LPA-producing phospholipase, many ATX's features and functions are dependent on the production of LPA. ATX and LPA together form the ATX-LPA functional axis. The present review summarizes the current progress in function and biological activities of ATX-LPA axis.
Asunto(s)
Lisofosfolípidos/fisiología , Hidrolasas Diéster Fosfóricas/fisiología , Animales , Movimiento Celular/fisiología , Proliferación Celular , Humanos , Lisofosfatidilcolinas/metabolismo , Lisofosfolípidos/metabolismo , Fosfolipasas/metabolismo , Hidrolasas Diéster Fosfóricas/metabolismo , Receptores Acoplados a Proteínas G/fisiologíaRESUMEN
Though hydroxylamine (NH2OH) is effective for accelerating pollutants degradation in Fenton and Fenton-like systems, the effect of anions simultaneously introduced by the hydroxylamine salts have always been ignored. Herein, effect of two commonly used hydroxylamine salts, hydroxylamine hydrochloride (NH2OH·HCl) and hydroxylamine sulfate [(NH2OH)2·H2SO4], for the degradation of dimethyl phthalate (DMP) in peroxymonosulfate (PMS)/Fe(II) system was comparatively investigated. Degradation efficiency of DMP with NH2OH·HCl was 1.6 times of that with same dosages of (NH2OH)2·H2SO4. SO4·-, Fe(IV) and ·OH formed in the PMS/Fe(II)/NH2OH system, but ·OH was the major species for DMP degradation. Addition of Cl- significantly improved the production of ·OH and Cl·, and the exposure dose of ·OH (CT·OH) was more than 10 times that of CTCl· as the concentration of Cl- increased to 1 mM. Calculations based on branching ratios of Cl· and ·OH indicated that the reactions of Cl- with SO4·- and Cl· with H2O were not the only production sources of ·OH in the system. Further experiments with methyl phenyl sulfoxide (PMSO) as the probe indicated that Cl- would facilitate the shift of reactive species from Fe(IV) to radicals (SO4·- or ·OH) in the system. Both hydroxylation and nitration intermediate products were detected in the oxidation of DMP. Cl- promoted the formation of hydroxylation intermediates and reduced the formation of nitration intermediates. This study revealed for the first time that Cl- could shift reactive species from Fe(IV) to radicals in PMS/Fe(II) system, raising attention to the influence of the coexisting anions (especially Cl-) for pollutants oxidation in iron-related oxidation processes.
Asunto(s)
Cloruros , Peróxidos , Compuestos Ferrosos , Hierro , Oxidación-ReducciónRESUMEN
Hydroxylamine showed an outstanding performance on enhancing the oxidation of pollutants in Fe(II) involved advanced oxidation processes, while the detailed reaction schemes have not been fully revealed. Specific functions of hydroxylamine in the oxidation of benzoic acid with Fe(II)/persulfate (PDS) system were explored. With the addition of hydroxylamine, degradation kinetics of benzoic acid deviated from both two-stage kinetics and pseudo first order kinetics, but could be interpreted well with binomial regression analysis. Degradation rate constant (kobs) of benzoic acid was calculated and showed the same variation trend with [hydroxylamine][Fe(III)]2/([Fe(II)][H+])2, the value of which was changed during reaction processes. A detailed kinetic model for simulating the degradation profile of benzoic acid with hydroxylamine acceleration was proposed for the first time and indicated that interactions of hydroxylamine and Fe(III) were fast equilibrium reactions, which was a dominant factor influencing the oxidation kinetics of benzoic acid in Fe(II)/hydroxylamine/PDS system. Comparative study showed that when 1.4â¯mM of ascorbic acid was added into Fe(II)/PDS system, degradation kinetics of benzoic acid was similar to that enhanced by hydroxylamine. However, when 0.6â¯mM or 1.0â¯mM of ascorbic acid was added, oxidation kinetics still presented as the two-stage profile. Kinetic simulations indicated that Fe(II) was produced slower from Fe(III)-ascorbic acid complexes than that with hydroxylamine, which caused the difference in oxidation kinetics. This study could improve our understanding about the effect of hydroxylamine and other reductants in promoting pollutants elimination in Fe(II)/PDS system.
Asunto(s)
Compuestos Ferrosos , Contaminantes Químicos del Agua , Compuestos Férricos , Hidroxilamina , Hidroxilaminas , Cinética , Oxidación-ReducciónRESUMEN
The fruiting body of Hericium erinaceus has been used to treat digestive system disorder-related diseases for over 2000 years in China. A novel polysaccharide, HEFP-2b, was obtained from H. erinaceus fruiting bodies. Physical and chemical analysis showed that HEFP-2b consisted of fucose, galactose, glucose, and mannose in molar ratio of 11.81:22.82:44.28:21.09, and that its molecular weight was 3.252 × 104 Da. The backbone of HEFP-2b consisted of â6)-linked-α-D-Glcp-(1â and â4)-ß-D-Galp-(1â and â3,6) -α-D-Manp linkage, with two side-branching units of (1â and â6)-ß-D-Galp and (1â and â4)-α-D-Manp, terminated by Glc and Fuc. The results of the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and cell cycle arrest experiments revealed that HEFP-2b considerably inhibited the growth of colon cancer cells (HCT-116) in vitro. The growth inhibitory effects of HEFP-2b correlated with their ability to arrest the cell cycle at the S-phase. Our results will provide valuable information for future studies on HEFP-2b as a novel health-promoting functional food ingredient that can be used for treating colon cancer.
Asunto(s)
Cuerpos Fructíferos de los Hongos/química , Hericium/química , Polisacáridos/química , Polisacáridos/aislamiento & purificación , Polisacáridos/farmacología , Puntos de Control de la Fase S del Ciclo Celular/efectos de los fármacos , Antineoplásicos/química , Antineoplásicos/aislamiento & purificación , Antineoplásicos/farmacología , Proliferación Celular/efectos de los fármacos , Supervivencia Celular , Neoplasias del Colon , Relación Dosis-Respuesta a Droga , Células HCT116 , Humanos , Monosacáridos/análisisRESUMEN
The fruiting bodies of Hericium erinaceus (Bull.) Pers. are commonly used in China in the treatment of digestive system diseases. In this work, the polysaccharides from the fruiting bodies of Hericium erinaceus (HEFPs) were extracted, and their effects on human colorectal cancer cells (HCT-116 and DLD1) were investigated in vitro. Our results showed that HEFPs were mainly composed of arabinose, galactose, glucose, and mannose at a molar ratio of 8.99 : 11.15 : 1.2 : 1.97. They significantly inhibited the growth of these cells by inducing apoptosis by the modulation of Bax and Bcl-2 expression, which in turn induced the loss of mitochondrial membrane potential, leading to the activation of cleaved-caspase-9 and cleaved-caspase-3. These results suggested that HEFPs induced apoptosis via the caspase-9-depedent intrinsic mitochondrial pathway. Furthermore, HEFPs increased the level of reactive oxygen species (ROS) in HCT-116 and DLD1 cells. The addition of the antioxidant N-acetyl-l-cysteine reduced the ability of HEFPs to trigger the intrinsic mitochondrial pathway, indicating the role of ROS generation in the upstream pathway of HEFP-induced apoptosis. Therefore, the results described in this study could be of interest for further studies in finding functional foods or alternative therapeutic agents against colorectal cancer.
Asunto(s)
Apoptosis/efectos de los fármacos , Hericium/metabolismo , Polisacáridos/farmacología , Transducción de Señal , Acetilcisteína/metabolismo , Agaricales/química , Caspasa 3/genética , Caspasa 3/metabolismo , Caspasa 9/genética , Caspasa 9/metabolismo , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Neoplasias Colorrectales/tratamiento farmacológico , Células HCT116 , Humanos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Polisacáridos/análisis , Especies Reactivas de Oxígeno/metabolismoRESUMEN
Although emerging evidence suggests positive association of arsenic (As) or sulfur dioxide (SO2) exposure with human diseases, reports concerning the effects of co-exposure of As and SO2 are lacking. Moreover, there is insufficient information in the literature about As and SO2 co-exposure to renal injury. In this study, we focus on the environmental problems of excessive As and SO2 that co-exist in many coal consumption areas. We used both C57BL/6 mice and 293T cells to detect toxicities of As and SO2 exposure alone or in combination. Our results showed that co-exposure significantly increased the hazard compared with exposure to As or SO2 alone. Mouse kidney tissue slices showed that co-exposure caused more severe diffuse sclerosing glomerulonephritis than As and SO2 exposure alone. Meanwhile experiments showed that apoptosis was aggravated by co-exposure of As and SO2 in 293T cells. Because As and SO2 cause cell toxicity through increasing oxidative stress, next we detected ROS and other oxidative stress parameters, and the results showed oxidative stress was increased by co-exposure compared with the other three groups. The expression levels of downstream genes in the NF-κB and caspase pathways were higher in the co-exposure group than in the groups of As or SO2 exposure alone in mice and 293T cells. Based on the above results, co-exposure could induce higher toxicity in vitro and in vivo compared with single exposure to As or SO2, indicating that people living in places that contaminated by As and SO2 may have higher chance to get renal injury.
Asunto(s)
Arsenitos/toxicidad , Contaminantes Ambientales/toxicidad , Enfermedades Renales/inducido químicamente , Riñón/efectos de los fármacos , FN-kappa B/metabolismo , Compuestos de Sodio/toxicidad , Dióxido de Azufre/toxicidad , Animales , Apoptosis/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Sinergismo Farmacológico , Células HEK293 , Humanos , Riñón/metabolismo , Riñón/patología , Enfermedades Renales/metabolismo , Enfermedades Renales/patología , Masculino , Ratones Endogámicos C57BL , Estrés Oxidativo/efectos de los fármacos , Transducción de SeñalRESUMEN
An immunoadsorbent that removes anti-acetylcholine receptor antibodies (AChRAb) in abnormal serum of myasthenia gravis (MG) patient was efficiently prepared by an expression product, the functional fragment of AChR(alpha205) fused with maltose binding protein (MBP). The ligand can then covalently bind to amylose resin through MBP fusion protein. It was shown from the result of this study with anti-AChR mice sera that the removal rate of AChRAb on this immunoadsorbent reached 87+/-10% (mean value of 10 mice) and the maximally binding capacity of AChRAb was approximately 260 microg/g immunoadsorbent (wet weight). Moreover, the immunoadsorption test of sera in two MG patients indicated that about 90% and 96% of abnormal AChRAb could be eliminated, while other serum components such as albumin, IgG, IgM and IgA only dropped 18%, 35%, 22%, 15% and 24%, 27%, 15%, 12%, respectively, for two MG patient sera. It is anticipated from this study that the immunoadsorbent reported here could, with further development, find its clinical application for removal of AChRAb from patient serum.
Asunto(s)
Autoanticuerpos/aislamiento & purificación , Autoantígenos/genética , Técnicas de Inmunoadsorción , Inmunoadsorbentes/síntesis química , Inmunoadsorbentes/metabolismo , Receptores Colinérgicos/inmunología , Proteínas Recombinantes de Fusión/síntesis química , Animales , Autoanticuerpos/sangre , Autoanticuerpos/metabolismo , Autoantígenos/inmunología , Sitios de Unión de Anticuerpos , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Electroforesis en Gel de Poliacrilamida/métodos , Humanos , Proteínas de Unión a Maltosa , Ratones , Ratones Endogámicos C57BL , Miastenia Gravis/sangre , Miastenia Gravis/inmunología , Plásmidos , Proteínas Recombinantes de Fusión/metabolismoRESUMEN
Proteases are important molecules that are involved in many key physiological processes. Protease signaling pathways are strictly controlled, and disorders in protease activity can result in pathological changes such as cardiovascular and inflammatory diseases, cancer and neurological disorders. Many proteases have been associated with increasing tumor metastasis in various human cancers, suggesting important functional roles in the metastatic process because of their ability to degrade the extracellular matrix barrier. Proteases are also capable of cleaving non-extracellular matrix molecules. Inhibitors of proteases to some extent can reduce invasion and metastasis of cancer cells, and slow down cancer progression. In this review, we focus on the role of a few proteases and their inhibitors in tumors as a basis for cancer prognostication and therapy.
Asunto(s)
Antineoplásicos/farmacología , Neoplasias/tratamiento farmacológico , Neoplasias/enzimología , Péptido Hidrolasas/química , Inhibidores de Proteasas/farmacología , Animales , Progresión de la Enfermedad , HumanosRESUMEN
Wnt/ß-catenin and Hedgehog/Gli signalings play key roles in multiple biogenesis such as embryonic development and tissue homeostasis. Dysregulations of these 2 pathways are frequently found in most cancers, particularly in colon cancer. Their crosstalk has been increasingly appreciated as an important mechanism in regulating colon cancer progression. Our studies into the link between Wnt/ß-catenin and Hedgehog/Gli signalings in colon cancer revealed several possible crosstalk points and suggested potential therapeutic strategies for colon cancer.
Asunto(s)
Neoplasias del Colon/metabolismo , Proteínas Hedgehog/metabolismo , Proteínas Oncogénicas/metabolismo , Transducción de Señal , Transactivadores/metabolismo , Proteínas Wnt/metabolismo , beta Catenina/metabolismo , Animales , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Neoplasias del Colon/tratamiento farmacológico , Humanos , Terapia Molecular Dirigida , Unión Proteica , Transducción de Señal/efectos de los fármacos , Proteína con Dedos de Zinc GLI1RESUMEN
Glucose regulated protein 78 (GRP78) is usually recognized as a chaperone in the endoplasmic reticulum. However, increasing evidence indicates that GRP78 can be translocated to the cell surface, acting as a signaling receptor for a variety of ligands. Since little is known about the secretion of GRP78 and its role in the progression of colon cancer we here focused on GRP78 from colon cancer cells, and purified GRP78 protein mimicking the secreted GRP78 was able to utilize cell surface GRP78 as its receptor, activating downstream PI3K/Akt and Wnt/ß-catenin signaling and promote colon cancer cell proliferation. Our study revealed a new mode of action of autocrine GRP78 in cancer progression: secreted GRP78 binds to cell surface GRP78 as its receptor and activates intracellular proliferation signaling.
Asunto(s)
Proliferación Celular/fisiología , Neoplasias del Colon/metabolismo , Proteínas de Choque Térmico/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Chaperón BiP del Retículo Endoplásmico , Células HT29 , Humanos , Transducción de Señal , Vía de Señalización WntRESUMEN
Dichlorodiphenyltrichloroethane (DDT) is a persistent organic pollutant, involved in the progression of many cancers, including liver cancer. However, the underlying mechanism(s) of DDT, especially how low doses DDT cause liver cancer, is poorly understood. In this study, we evaluated the impact of p,p'-DDT on the growth of hepatocellular carcinoma using both in vitro and in vivo models. The present data indicated that the proliferation of HepG2 cells was strikingly promoted after exposed to p,p'-DDT for 4 days. In addition, reactive oxygen species (ROS) content was significantly elevated, accompanied with inhibitions of γ-glutamylcysteine synthetase (γ-GCS) and superoxide dismutase (SOD) activities. Interestingly, the levels of ß-catenin and its downstream target genes (c-Myc and CyclinD1) were significantly up-regulated, and co-treatment of NAC, the ROS inhibitor, inhibited these over-expressed proteins. Moreover, the p,p'-DDT-stimulated proliferation of HepG2 cells could be reversed after NAC or ß-catenin siRNA co-treatment. Likewise, p,p'-DDT treatment increased the growth of tumor in nude mice, stimulated oxidative stress and Wnt/ß-catenin pathway. Our study indicates that low doses p,p'-DDT exposure promote the growth of hepatocellular carcinoma via Wnt/ß-catenin pathway which is activated by oxidative stress. The finding suggests an association between low dose DDT exposure and liver cancer growth.
Asunto(s)
Carcinógenos/toxicidad , Carcinoma Hepatocelular/metabolismo , Proliferación Celular/efectos de los fármacos , DDT/toxicidad , Neoplasias Hepáticas/metabolismo , Vía de Señalización Wnt/efectos de los fármacos , beta Catenina/metabolismo , Animales , Antioxidantes/farmacología , Carcinoma Hepatocelular/patología , Ciclina D1/metabolismo , Relación Dosis-Respuesta a Droga , Glutamato-Cisteína Ligasa/antagonistas & inhibidores , Glutamato-Cisteína Ligasa/metabolismo , Células Hep G2 , Humanos , Neoplasias Hepáticas/patología , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Estrés Oxidativo/efectos de los fármacos , Proteínas Proto-Oncogénicas c-myc/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Superóxido Dismutasa/antagonistas & inhibidores , Superóxido Dismutasa/metabolismo , Factores de Tiempo , Carga Tumoral/efectos de los fármacosRESUMEN
An open reading frame of the alpha-subunit 1-205 residues (alpha205) of human acetylcholine receptor (AchR) was amplified by PCR with pUC-AChR alpha205 as the template and inserted into vector pMAL-c2X. The constructed pMAR alpha205 was transferred into E. coli BL21 which were then grown in LB medium. The amount of soluble MBP-AChR alpha205 protein reached about 25% of total soluble proteins from the cell lysate. Using amylose-affinity chromatography, about 35 mg MBP-AChR alpha205 could be obtained from 1 l culture. Western blot analysis and ELISA showed that immunoreactivities of both MBP-AChR alpha205 and AChR alpha205 were similar to that of AChR alpha-subunit from Torpedo.