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1.
J Med Chem ; 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-39047113

RESUMEN

Ferroptosis, a distinctive form of programmed cell death, has been implicated in numerous pathological conditions, and its inhibition is considered a promising therapeutic strategy. Currently, there is a scarcity of efficient antagonists for directly regulating intracellular ferrous iron. Ferritinophagy, an essential process for supplying intracellular labile iron, relies on nuclear receptor coactivator 4 (NCOA4), a selective autophagy receptor for the ferritin iron storage complex, thus playing a pivotal role in ferritinophagy. In this study, we reported a novel von Hippel-Lindau-based NCOA4 degrader, V3, as a potent ferroptosis inhibitor with an intracellular ferrous iron inhibition mechanism. V3 significantly reduced NCOA4 levels and downregulated intracellular ferrous iron (Fe2+) levels, thereby effectively suppressing ferroptosis induced by multiple pathways within cells and alleviating liver damage. This research presents a chemical knockdown tool targeting NCOA4 for further exploration into intracellular ferrous iron in ferroptosis, offering a promising therapeutic avenue for ferroptosis-related acute liver injury.

2.
Transcult Psychiatry ; : 13634615231225158, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38356281

RESUMEN

Despite the universal nature of suffering, few studies have examined how Indigenous ethnic minorities in non-western regions understand and respond to adversity. This study explored the epistemology of suffering among the Temiar ethnic group of Peninsular Malaysia using participant observation and semi-structured interviews. Interview transcripts of 43 participants were coded through inductive thematic analysis and a consensual qualitative approach. Three-tier themes were defined and named after subsequent analysis of core ideas and domains in the data. Major adversities reported included a lack of basic needs, lack of land-rights and unjust treatment from authorities, destruction of the forest environment and livelihood, and lack of accessibility and facilities, which were attributed to authorities' negligence of responsibilities, increasing human-animal conflict, environmental threats and imposed lifestyle changes. Faced with adversity, the Temiar endeavoured to survive by working crops and gathering forest resources. They utilized resources from family, fellow villagers, external agencies and spiritual-religious traditions. Theoretical mapping of attribution styles into the Ecological Rationality Framework revealed predominantly external-focused and concrete-perceptual rationalities privileged by strong-ties societies. These findings pointed to the resilience of a strong-ties community while adapting to the systemic suffering and risk factors stemming from a rationality mismatch with modernization and globalization trends. To conclude, we advocate for culture-sensitive mental health and psychiatric practices, as well as sustainable development for the well-being of Indigenous communities locally and globally.

3.
Org Lett ; 26(6): 1201-1206, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38308848

RESUMEN

We developed an asymmetric decarboxylative allylic alkylation of vinylethylene carbonates with α-fluoro pyridinyl acetates through a synergistic palladium/copper catalysis. This protocol provides chiral allylic alcohol with carbon-fluorine quaternary stereogenic centers in good yield with good enantioselectivities and excellent regioselectivities. The utility of this approach was further demonstrated via a gram-scale experiment and derivatizations of the product.

4.
Cell Mol Biol (Noisy-le-grand) ; 69(9): 229-233, 2023 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-37807307

RESUMEN

Rheumatoid arthritis or joint rheumatism is the most common systemic inflammatory disease of the joints and is considered one of the chronic autoimmune diseases. T cells and other immune cells are called to the synovial tissue and cause this disease to progress. Autophagy is a process that is associated with the breakdown of intracellular organelles. As a regulator of cell homeostasis, it can affect the activation of immune cells and participate in the pathogenesis of rheumatoid arthritis. This study aimed to evaluate the gene expression level of autophagy genes in two groups of rheumatoid arthritis patients and healthy individuals. For this purpose, peripheral blood was obtained from two groups of people, including 40 rheumatoid arthritis patients, and 40 healthy individuals. The expression of two genes related to autophagy, Atg5, and Beclin-1, was evaluated in peripheral blood cells using the real-time PCR method. The results showed that the expression of the Beclin-1 gene increased by 2.21 times in rheumatoid arthritis patients compared to healthy individuals (P = 0.024). The expression of the Atg5 gene in rheumatoid arthritis patients increased by 1.53 times compared to healthy subjects (P = 0.041). In general, this study showed that in rheumatoid arthritis patients, increased expression of autophagy genes could be involved in the pathogenesis of this disease. In other words, the findings showed that reducing autophagy can reduce the severity of the disease in people with rheumatoid arthritis.


Asunto(s)
Artritis Reumatoide , Humanos , Beclina-1/genética , Beclina-1/metabolismo , Artritis Reumatoide/metabolismo , Membrana Sinovial/metabolismo , Linfocitos T/metabolismo , Autofagia/genética
5.
Artículo en Inglés | MEDLINE | ID: mdl-36361278

RESUMEN

Stepladders are compact, foldable ladders with flat steps and a platform. Despite all the research and design efforts, there are still limitations in terms of the multifunctionality, usability and simplicity of stepladders and related variants. By combining ideas, features and functions from patent literature, existing products and scientific journals, this study aims to conceptualise a multifunctional stepladder for improved usability. Five concepts are created, which are screened and evaluated against a set of criteria to select the best concept for improved usability, divided into three categories: simplicity, effectiveness and efficiency. The result is a versatile invention that functions as a stepladder, walker, wheelchair and Pilates chair, suitable for older people and caregivers in nursing homes. It allows medical records or supplies to be retrieved from high places without the need for inappropriate aids. The invention can replace wheelchairs and walkers and converts into a Pilates chair to provide a mobile exercise option for older people. The concept offers older people flexibility and independence in terms of mobility and healthcare, while saving space in the nursing home. Further design studies, prototyping and testing are needed before this idea can go into production.


Asunto(s)
Cuidadores , Silla de Ruedas , Humanos , Anciano , Casas de Salud , Andadores , Ejercicio Físico
6.
Int J Adv Couns ; 44(3): 550-568, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35698476

RESUMEN

Many experiential learning teaching models are developed in Western cultures, with their efficacy not tested in non-Western cultures, especially in counseling education. This study examined the learning experiences of students (n = 52) enrolled in a culturally contextualized experiential teaching method implemented across a 3-year period in a Malaysian university Masters-level group counseling course. The course changes included group demonstrations by lecturers and peers, live group participation and observation, group dynamics map drawing and debriefing, paired group proposal writing and presentation, and group note- taking. This study adopted a mixed method approach with a short survey consisting of both standardized scales and open-ended questions, administered at the beginning and end of each 12-week semester. Archival data on students' evaluation was also retrieved from the year before the intervention, to compare with the 3 years of intervention. Results showed a statistically significant improvement in students' perceived group leadership skills and leadership characteristics at the end of the course. Students' overall satisfaction with the course quality also improved significantly from the year prior to the implementation of the new teaching method. Qualitative coding identified three major themes-active learning classroom that led to confidence in group counseling knowledge and skills; experiential activities in the tutorial sessions, with opportunities to carry out their proposed group activities; and formative feedback given throughout the semester during tutorial settings contributing to the higher course satisfaction rate. To conclude, we discuss the implications of contextualized experiential learning for higher education counseling pedagogy in the Asian region. Supplementary information: The online version contains supplementary material available at 10.1007/s10447-022-09471-3.

7.
J Photochem Photobiol B ; 187: 66-75, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30099271

RESUMEN

Flower-like ZnO micro/nanostructures were successfully fabricated via a surfactant-free co-precipitation method. The as-synthesized product was characterized using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersive X-ray (EDX), transmission electron microscopy (TEM), fourier transform infrared spectroscopy (FTIR), UV-vis diffuse reflectance spectroscopy (UV-vis DRS) and photoluminescence (PL) analyses. In the presence of visible light irradiation, the as-synthesized flower-like ZnO showed higher antibacterial activities against Enterococcus faecalis (E. faecalis) and Micrococcus luteus (M. luteus) than that of commercial ZnO. The excellent antibacterial performance of synthesized flower-like ZnO was also observed via the bacterial morphological change, K+ ions leakage and protein leakage in extracellular suspension. In addition, the FTIR investigation on both treated bacteria further confirmed the bacterial membrane damage via cellular substance alteration. The enhancement of the antibacterial activity of synthesized ZnO can be attributed to the unique flower-like morphology which can increase the surface OH- groups and the quantity of photogenerated electron-hole pair available to participate in the photocatalytic reaction. The reactive oxidizing species (ROS) scavengers experiments showed that H2O2 played a main role in the photocatalytic antibacterial process. Our study showed that the synthesized flower-like ZnO micro/nanostructures can act as efficient antibacterial agents in the photocatalytic antibacterial process under visible light irradiation.


Asunto(s)
Antibacterianos/química , Luz , Óxido de Zinc/química , Antioxidantes/química , Catálisis , Enterococcus faecalis/efectos de los fármacos , Peróxido de Hidrógeno/toxicidad , Micrococcus luteus/efectos de los fármacos , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Nanoestructuras/química , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X , Óxido de Zinc/síntesis química , Óxido de Zinc/farmacología
8.
ACS Med Chem Lett ; 7(9): 835-40, 2016 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-27660687

RESUMEN

Directly disrupting the Keap1-Nrf2 protein-protein interaction (PPI) has emerged as an attractive way to activate Nrf2, and Keap1-Nrf2 PPI inhibitors have been proposed as potential agents to relieve inflammatory and oxidative stress diseases. In this work, we investigated the diacetic moiety around the potent Keap1-Nrf2 PPI inhibitor DDO1018 (2), which was reported by our group previously. Exploration of bioisosteric replacements afforded the ditetrazole analog 7, which maintains the potent PPI inhibition activity (IC50 = 15.8 nM) in an in vitro fluorescence polarization assay. Physicochemical property determination demonstrated that ditetrazole replacement can improve the drug-like property, including elevation of pK a, log D, and transcellular permeability. Additionally, 7 is more efficacious than 2 on inducing the expression of Nrf2-dependent gene products in cells. This study provides an alternative way to replace the diacetic moiety and occupy the polar subpockets in Keap1, which can benefit the subsequent development of Keap1-Nrf2 PPI inhibitor.

9.
Sci Rep ; 6: 26585, 2016 05 24.
Artículo en Inglés | MEDLINE | ID: mdl-27215610

RESUMEN

Ulcerative colitis (UC) is a chronic relapsing-remitting form of inflammatory bowel disease (IBD) that increases the risk of colorectal cancer, the third most common malignancy in humans. Oxidative stress is a risk factor for the development of UC. The Keap1-Nrf2-ARE pathway is one of the most important defensive mechanisms against oxidative and/or electrophilic stresses. In this study, we identified CPUY192018 as a potent small-molecule inhibitor of the Keap1-Nrf2 PPI, investigated the cyto-protective effects of CPUY192018 on the NCM460 colonic cells and evaluated whether treatment with the inhibitor of the Keap1-Nrf2 PPI exerts protection on an established experimental model of UC induced by dextran sodium sulfate (DSS). Our study clearly demonstrated that CPUY192018 had a cytoprotective effect against DSS in both NCM460 cells and mouse colon via the activation of Nrf2 signaling. These results suggested that activation of Nrf2 by directly inhibiting the Keap1-Nrf2 PPI may be beneficial as a treatment for UC.


Asunto(s)
Colitis/tratamiento farmacológico , Colon/citología , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Bibliotecas de Moléculas Pequeñas/administración & dosificación , Animales , Línea Celular , Colitis/inducido químicamente , Colitis/metabolismo , Colon/efectos de los fármacos , Sulfato de Dextran/efectos adversos , Modelos Animales de Enfermedad , Células Hep G2 , Humanos , Ratones , Unión Proteica/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Bibliotecas de Moléculas Pequeñas/farmacología
10.
Med Res Rev ; 36(5): 924-63, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27192495

RESUMEN

The Keap1-Nrf2-ARE ((Kelch-like ECH-Associating protein 1) nuclear factor erythroid 2 related factor 2-antioxidant response element) pathway is one of the most important defense mechanisms against oxidative and/or electrophilic stresses, and it is closely associated with inflammatory diseases, including cancer, neurodegenerative diseases, cardiovascular diseases, and aging. In recent years, progress has been made in strategies aimed at modulating the Keap1-Nrf2-ARE pathway. The Nrf2 activator DMF (Dimethylfumarates) has been approved by the FDA as a new first-line oral drug to treat patients with relapsing forms of multiple sclerosis, while a phase 3 study of another promising candidate, CDDO-Me, was terminated for safety reasons. Directly inhibiting Keap1-Nrf2 protein-protein interactions as a novel Nrf2-modulating strategy has many advantages over using electrophilic Nrf2 activators. The development of Keap1-Nrf2 protein-protein interaction inhibitors has become a topic of intense research, and potent inhibitors of this target have been identified. In addition, inhibiting Nrf2 activity has attracted an increasing amount of attention because it may provide an alternative cancer therapy. This review summarizes the molecular mechanisms and biological functions of the Keap1-Nrf2-ARE system. The main focus of this review is on recent progress in studies of agents that target the Keap1-Nrf2-ARE pathway and the therapeutic applications of such agents.


Asunto(s)
Antiinflamatorios/farmacología , Elementos de Respuesta Antioxidante/fisiología , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Animales , Elementos de Respuesta Antioxidante/efectos de los fármacos , Humanos , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Inflamación/prevención & control , Proteína 1 Asociada A ECH Tipo Kelch/antagonistas & inhibidores , Terapia Molecular Dirigida , Factor 2 Relacionado con NF-E2/antagonistas & inhibidores , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/farmacología , Transducción de Señal/efectos de los fármacos
11.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 35(9): 958-63, 2010 Sep.
Artículo en Chino | MEDLINE | ID: mdl-20871161

RESUMEN

OBJECTIVE: To explore the role of IL-21 in the pathogenesis of myasthenia gravis (MG) and its influence on the the class switch of anti-AChR antibodies. METHODS: Blood was taken from 26 patients and 18 healthy controls, and the expression of IL-21R mRNA in peripheral blood mononuclear cells (PBMCs) was detected by RT-PCR. The expression of IL-21R on B lymphocytes was measured by flow cytometry, while the concentrations of serum IL-21 and the levels of anti-AChR-IgG and its isotype IgG(1), IgG(2), and IgG(3) were tested by ELISA. RESULTS: The serum concentration of IL-21 in the MG group was higher than that in the control group (31.686±8.499 pg/mL, 15.147±6.366 pg/mL) and the difference was significant (P<0.01). IL-21R mRNA expressed on PBMCs in the MG group was higher than that in the control group (0.139±0.052, 0.101±0.022), and the difference was significant (P<0.05). There was no difference between ocular MG and generalized MG subgroup (P>0.05). Compared with the control group, the expression of IL-21R on B lymphocytes also increased in the MG group (P<0.05). In the anti-AChR-Ab positive MG group, the serum concentration of IL-21 showed positive correlation with anti-AChR-IgG(P<0.05),but no correlation with its isotype IgG(1), IgG(2), and IgG(3), respectively(P>0.05). Expression of IL-21R mRNA in the PBMCs showed no correlation with the level of serum anti-AChR-IgG and its isotype IgG(1), IgG(2), and IgG(3), respectively(P>0.05); however the expression of IL-21R in B lymphocytes showed positive correlation with anti-AChR-IgG and it's isotype IgG(1) and IgG(3) (P<0.05,P<0.01,P<0.05), but no correlation with IgG(2) (P>0.05). CONCLUSION: IL-21 might induce the class switch of anti-AChR antibodies to IgG(1) and IgG(3) isotype through IL-21R on B lymphocytes which promotes the pathogenesis of the MG.


Asunto(s)
Autoanticuerpos/inmunología , Cambio de Clase de Inmunoglobulina/inmunología , Interleucinas/sangre , Miastenia Gravis/inmunología , Receptores Colinérgicos/inmunología , Adolescente , Adulto , Autoanticuerpos/clasificación , Femenino , Humanos , Inmunoglobulina G/clasificación , Interleucinas/genética , Masculino , Persona de Mediana Edad , Miastenia Gravis/sangre , ARN Mensajero/sangre , ARN Mensajero/genética , Receptores de Interleucina-21/sangre , Receptores de Interleucina-21/genética , Adulto Joven
12.
Mol Cancer Ther ; 5(9): 2158-64, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16985048

RESUMEN

The ability of cancer cells to undergo invasion and migration is a prerequisite for tumor metastasis. Rho, a Ras-related small GTPase, and the Rho-associated coiled coil-containing protein kinases (Rho kinases, ROCK1 and ROCK2) are key regulators of focal adhesion, actomyosin contraction, and thus cell motility. Inhibitors of this pathway have been shown to inhibit tumor cell motility and metastasis. Here, we show that fasudil [1-(5-isoquinolinesulfonyl)-homopiperazine], an orally available inhibitor of Rho kinases, and its metabolite 1-(hydroxy-5-isoquinoline sulfonyl-homopiperazine) (fasudil-OH) modify tumor cell morphology and inhibit tumor cell migration and anchorage-independent growth. In addition, we show that fasudil inhibited tumor progression in three independent animal models. In the MM1 peritoneal dissemination model, tumor burden and ascites production were reduced by > 50% (P < 0.05). In the HT1080 experimental lung metastasis model, fasudil decreased lung nodules by approximately 40% (P < 0.05). In the orthotopic breast cancer model with MDA-MB-231, there were 3-fold more tumor-free mice in the fasudil-treated group versus saline control group (P < 0.01). Fasudil has been approved for the treatment of cerebral vasospasm and associated cerebral ischemic symptoms. In patients, fasudil is well tolerated without any serious adverse reactions. Therefore, the concept of Rho kinase inhibition as an antimetastatic therapy for cancer can now be clinically explored.


Asunto(s)
1-(5-Isoquinolinesulfonil)-2-Metilpiperazina/análogos & derivados , Neoplasias de la Mama/tratamiento farmacológico , Fibrosarcoma/tratamiento farmacológico , Péptidos y Proteínas de Señalización Intracelular/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Quinasas Asociadas a rho/antagonistas & inhibidores , 1-(5-Isoquinolinesulfonil)-2-Metilpiperazina/farmacología , Animales , Neoplasias de la Mama/enzimología , Neoplasias de la Mama/patología , Adhesión Celular/efectos de los fármacos , Adhesión Celular/fisiología , Procesos de Crecimiento Celular/efectos de los fármacos , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Progresión de la Enfermedad , Femenino , Fibrosarcoma/enzimología , Fibrosarcoma/patología , Humanos , Masculino , Ratones , Ratones Desnudos , Ratas , Ensayos Antitumor por Modelo de Xenoinjerto
13.
Gene ; 380(2): 111-9, 2006 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-16879932

RESUMEN

The detection and purification of proteins are often time-consuming and frequently involve complicated protocols. The addition of a peptide tag to recombinant proteins can make this process more efficient. Many of the commonly used tags, such as Flagtrade mark, Myc, HA and V5 are recognized by specific monoclonal antibodies and therefore, allow immunoaffinity-based purification. Enhancing the current scope of flexibility in using diverse peptide tags, we report here the development of a novel, short polypeptide tag (Tab2) for detection and purification of recombinant proteins. The Tab2 epitope corresponds to the NH2-terminal seven amino acid residues of human TGFalpha. A monoclonal anti-Tab2 antibody was raised and characterized. To investigate the potential of this peptide sequence as a novel tag for recombinant proteins, we expressed several different recombinant proteins containing this tag in E. coli, baculovirus, and mammalian cells. The data presented demonstrates the Tab2 tag-anti-Tab2 antibody combination is a reliable tool enabling specific Western blot detection, FACS analysis, and immunoprecipitation as well as non-denaturing protein affinity purification.


Asunto(s)
Cromatografía de Afinidad/métodos , Epítopos/química , Fragmentos de Péptidos/inmunología , Proteínas Recombinantes de Fusión/aislamiento & purificación , Factor de Crecimiento Transformador alfa/genética , Secuencias de Aminoácidos/genética , Animales , Anticuerpos Monoclonales/inmunología , Especificidad de Anticuerpos/inmunología , Células Cultivadas , Clonación Molecular , Ensayo de Inmunoadsorción Enzimática/métodos , Citometría de Flujo/métodos , Vectores Genéticos/síntesis química , Humanos , Inmunoprecipitación/métodos , Insectos , Fragmentos de Péptidos/genética , Fosfotransferasas/genética , Fosfotransferasas/aislamiento & purificación , Fosfotransferasas/metabolismo , Unión Proteica/inmunología , Estructura Terciaria de Proteína/genética , Receptores de Superficie Celular/genética , Receptores de Superficie Celular/aislamiento & purificación , Receptores de Superficie Celular/metabolismo , Proteínas Recombinantes de Fusión/síntesis química , Proteínas Recombinantes de Fusión/inmunología , Factor de Crecimiento Transformador alfa/química , Factor de Crecimiento Transformador alfa/metabolismo
14.
Clin Biomech (Bristol, Avon) ; 21(8): 860-3, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16716473

RESUMEN

BACKGROUND: The fibrous mediopatellar plica can cause high contact pressure on the adjacent articular cartilage and lead to its degeneration. The purpose of this study was to investigate the biomechanical properties of the plica and to correlate this with the plica's fiber content and patients' ages. METHODS: An experimental study on the tensile strength of the mediopatellar plica was conducted using high precision micro-force tensile tests. These tests were undertaken on plica specimens taken from 50 knees of patients with different ages. The force-deflection curves resulting from these tests were recorded and transferred to stress-stain curves to obtain the Young's moduli of these specimens. In addition, pathological tissue dyeing tests were used to assess the fiber content ratio of each specimen. The relationship of the Young's moduli of these specimens with the severity of their pathologic change was also evaluated. FINDINGS: The Young's modulus of the plica was found to be ranging from 10 to 110 MPa. It has positive correlation with patient's age. The relationship between the fiber content ratio and Young's modulus can be fitted properly using a quadratic regression model. The Young's modulus of the plica was also positively correlated with the severity of its pathologic change. INTERPRETATION: The test results indicated that as patients get older, the fiber content of the mediopatellar plica and the Young's modulus of the plica will increase accordingly. We also demonstrated that the Young's modulus of the medial plica was positively correlated with the severity of the plica lesion.


Asunto(s)
Materiales Biocompatibles , Traumatismos de la Rodilla/patología , Traumatismos de la Rodilla/cirugía , Rodilla/anatomía & histología , Adulto , Factores de Edad , Anciano , Fenómenos Biomecánicos , Cartílago/patología , Femenino , Humanos , Masculino , Ensayo de Materiales , Persona de Mediana Edad , Presión , Estrés Mecánico , Resistencia a la Tracción
15.
Cancer Res ; 66(7): 3611-9, 2006 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-16585186

RESUMEN

Hepsin is a type II transmembrane serine protease that is expressed in normal liver, and at lower levels in kidney, pancreas, and testis. Several studies have shown that hepsin mRNA is significantly elevated in most prostate tumors, as well as a significant fraction of ovarian and renal cell carcinomas and hepatomas. Although the overexpression of mRNA in these tumors has been extensively documented, there has been conflicting literature on whether hepsin plays a role in tumor cell growth and progression. Early literature implied a role for hepsin in human tumor cell proliferation, whereas recent studies with a transgenic mouse model for prostate cancer support a role for hepsin in tumor progression and metastases. To evaluate this issue further, we have expressed an activatable form of hepsin, and have generated a set of monoclonal antibodies that neutralize enzyme activity. The neutralizing antibodies inhibit hepsin enzymatic activity in biochemical and cell-based assays. Selected neutralizing and nonneutralizing antibodies were used in cell-based assays with tumor cells to evaluate the effect of antibodies on tumor cell growth and invasion. Neutralizing antibodies failed to inhibit the growth of prostate, ovarian, and hepatoma cell lines in culture. However, potent inhibitory effects of the antibodies were seen on invasion of ovarian and prostate cells in transwell-based invasion assays. These results support a role for hepsin in tumor cell progression but not in primary tumor growth. Consistent with this, immunohistochemical experiments with a mouse monoclonal antibody reveal progressively increased staining of prostate tumors with advanced disease, and in particular, extensive staining of bone metastatic lesions.


Asunto(s)
Anticuerpos Monoclonales/farmacología , Neoplasias Ováricas/enzimología , Neoplasias de la Próstata/enzimología , Serina Endopeptidasas/metabolismo , Inhibidores de Serina Proteinasa/farmacología , Secuencia de Aminoácidos , Anticuerpos Monoclonales/inmunología , Procesos de Crecimiento Celular/efectos de los fármacos , Procesos de Crecimiento Celular/fisiología , Línea Celular Tumoral , Clonación Molecular , Femenino , Humanos , Inmunohistoquímica , Masculino , Datos de Secuencia Molecular , Invasividad Neoplásica , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/patología , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/patología , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/genética , Serina Endopeptidasas/biosíntesis , Serina Endopeptidasas/genética , Serina Endopeptidasas/inmunología , Inhibidores de Serina Proteinasa/inmunología
16.
Cancer Res ; 65(18): 8397-405, 2005 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-16166318

RESUMEN

Gene expression analysis showed that a human mindin homologue, mindin/RG-1, is expressed selectively in prostate tissues and that its expression level is elevated in some prostate tumors. Mindin/RG-1 protein expression is maintained in >80% of prostate cancers metastatic to bone or lymph nodes as well as in locally recurrent tumors in androgen-unresponsive patients. In contrast, mindin/RG-1 expression in other normal tissues is significantly lower than that seen in the prostate. A fully human antibody, 19G9, was generated against mindin/RG-1 protein and was shown to accumulate at high abundance in LNCaP tumor xenografts. Conjugates of this antibody with the chelator CHX-A''-DTPA were generated and radiolabeled with either 111In, 90Y, or 86Y. Small animal positron emission tomography imaging with the 86Y-radiolabeled conjugate showed very specific accumulation of the antibody in LNCaP tumor xenografts with clear tumor delineation apparent at 4 hours. The therapeutic efficacy of [90Y]-CHX-A''-DTPA-19G9 was evaluated in mice bearing LNCaP xenografts. A dose-finding study identified a nontoxic therapeutic dose to be approximately 75 microCi. Significant antitumor effects were seen with a single administration of radiolabeled antibody to animals bearing 200 to 400 mm3 tumors. Inhibition of tumor growth was observed in all treated animals over a 49-day period. At 49 days posttreatment, slow tumor growth recurred but this could be prevented for an additional 40-day period by a second administration of a 75 microCi dose at day 49. We conclude that [90Y]-CHX-A''-DTPA-19G9 is a novel antibody conjugate that has considerable promise for therapy of metastatic prostate cancer in androgen-unresponsive patients.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Proteínas de la Matriz Extracelular/inmunología , Inmunotoxinas/inmunología , Neoplasias de la Próstata/radioterapia , Radioinmunoterapia/métodos , Secuencia de Aminoácidos , Animales , Anticuerpos Monoclonales/farmacocinética , Anticuerpos Monoclonales/farmacología , Especificidad de Anticuerpos , Neoplasias Óseas/metabolismo , Neoplasias Óseas/secundario , Células CHO , Cricetinae , Relación Dosis-Respuesta Inmunológica , Proteínas de la Matriz Extracelular/biosíntesis , Proteínas de la Matriz Extracelular/genética , Humanos , Inmunotoxinas/farmacocinética , Inmunotoxinas/farmacología , Isotiocianatos/inmunología , Isotiocianatos/farmacocinética , Isotiocianatos/farmacología , Masculino , Datos de Secuencia Molecular , Ácido Pentético/análogos & derivados , Ácido Pentético/inmunología , Ácido Pentético/farmacocinética , Ácido Pentético/farmacología , Tomografía de Emisión de Positrones , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/inmunología , Neoplasias de la Próstata/metabolismo , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Distribución Tisular , Ensayos Antitumor por Modelo de Xenoinjerto , Radioisótopos de Itrio/administración & dosificación , Radioisótopos de Itrio/farmacocinética , Radioisótopos de Itrio/farmacología
17.
Cancer Res ; 65(7): 2846-53, 2005 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-15805286

RESUMEN

Radiotherapy is an effective approach for the treatment of local prostate cancer. However, once prostate cancer metastasizes, radiotherapy cannot be used due to the distribution of multiple metastases to lymph nodes and bones. In contrast, radioimmunotherapy should still be efficacious in metastatic prostate cancer as radioisotopes are brought to tumor cells by targeting antibodies. Here we identify and validate a prostate-expressed molecule, tomoregulin, as a target for radioimmunotherapy of prostate cancer. Tomoregulin is a transmembrane protein selectively expressed in the brain, prostate, and prostate cancer, but not expressed in other normal tissues. Immunohistochemical studies of tomoregulin protein in clinical samples show its location in the luminal epithelium of normal prostate, benign prostatic hyperplasia, and prostatic intraepithelial neoplasia. More importantly, the tomoregulin protein is expressed in primary prostate tumors and in their lymph node and bone metastases. The nature of tomoregulin as a transmembrane protein and its tissue-specific expression make tomoregulin an attractive target for radioimmunotherapy, in which tomoregulin-specific antibodies will deliver a radioisotope to prostate tumor cells and metastases. Indeed, biodistribution studies using a prostate tumor xenograft model showed that the (111)In-labeled anti-tomoregulin antibody 2H8 specifically recognizes tomoregulin protein in vivo, leading to a strong tumor-specific accumulation of the antibody. In efficacy studies, a single i.p. dose of 150 microCi (163 microg) (90)Y-labeled 2H8 substantially inhibits the growth rate of established LNCaP human prostate tumor xenograft in nude mice but produces no overt toxicity despite cross-reactivity of 2H8 with mouse tomoregulin. Our data clearly validate tomoregulin as a target for radioimmunotherapy of prostate cancer.


Asunto(s)
Inmunotoxinas/uso terapéutico , Radioisótopos de Indio/uso terapéutico , Proteínas de la Membrana/biosíntesis , Proteínas de Neoplasias/biosíntesis , Neoplasias de la Próstata/radioterapia , Radioisótopos/uso terapéutico , Iterbio/uso terapéutico , Animales , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/farmacocinética , Anticuerpos Monoclonales/uso terapéutico , Encéfalo/metabolismo , Línea Celular Tumoral , Humanos , Inmunoglobulina G/inmunología , Inmunoglobulina G/metabolismo , Inmunotoxinas/inmunología , Inmunotoxinas/farmacocinética , Masculino , Proteínas de la Membrana/genética , Proteínas de la Membrana/inmunología , Ratones , Ratones Desnudos , Metástasis de la Neoplasia , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/inmunología , Próstata/metabolismo , Neoplasias de la Próstata/inmunología , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Radioinmunoterapia , Radiofármacos/inmunología , Radiofármacos/farmacocinética , Radiofármacos/uso terapéutico , Distribución Tisular , Ensayos Antitumor por Modelo de Xenoinjerto
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