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1.
ACS Chem Neurosci ; 15(3): 593-607, 2024 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-38214579

RESUMO

Objective: Schisandrin B (Sch B) is a bioactive dibenzocyclooctadiene derizative that is prevalent in the fruit of Schisandra chinensis. Numerous studies have demonstrated that Sch B has a neuroprotective action by reducing oxidative stress and effectively preventing inflammation. It follows that Sch B is a potential treatment for Alzheimer's disease (AD). However, the drug's solubility, bioavailability, and lower permeability of the blood-brain barrier (BBB) can all reduce its efficacy during the therapy process. Therefore, this study constructed borneol-modified schisandrin B micelles (Bor-Sch B-Ms), which increase brain targeting by accurately delivering medications to the brain, effectively improving bioavailability. High therapeutic efficacy has been achieved at the pathological site. Methods: Bor-Sch B-Ms were prepared using the thin film dispersion approach in this article. On the one hand, to observe the targeting effect of borneol, we constructed a blood-brain barrier (BBB) model in vitro and studied the ability of micelles to cross the BBB. On the other hand, the distribution of micelle drugs and their related pharmacological effects on neuroinflammation, oxidative stress, and neuronal damage were studied through in vivo administration in mice. Results: In vitro studies have demonstrated that the drug uptake of bEnd.3 cells was increased by the borneol alteration on the surface of the nano micelles, implying that Bor-Sch B-Ms can promote the therapeutic effect of N2a cells. This could result in more medicines entering the BBB. In addition, in vivo studies revealed that the distribution and circulation time of medications in the brain tissue were significantly higher than those in other groups, making it more suitable for the treatment of central nervous system diseases. Conclusion: As a novel nanodrug delivery system, borneol modified schisandrin B micelles have promising research prospects in the treatment of Alzheimer's disease.


Assuntos
Doença de Alzheimer , Barreira Hematoencefálica , Canfanos , Lignanas , Compostos Policíclicos , Camundongos , Animais , Micelas , Doença de Alzheimer/tratamento farmacológico , Células Endoteliais , Ciclo-Octanos
2.
Drug Dev Ind Pharm ; 49(9): 559-571, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37649422

RESUMO

OBJECTIVE: Alzheimer's disease (AD) is a neurodegenerative disease that is associated with aging and is influenced by both genetic and environmental factors. Several studies and clinical trials have demonstrated that resveratrol (Res) and salidroside (Sal) are not only biologically safe but also influence AD biomarker trajectories. However, their clinical applications have been quite limited due to poor specificity, low solubility, and insufficient blood-brain barrier (BBB) penetration. Therefore, we developed a nano-drug delivery system in which Res and Sal were encapsulated in liposomes, which were surface-modified with ApoE (ApoE-Res/Sal-Lips) to compensate for these deficiencies. METHOD: In this study, ApoE-Res/Sal-Lips were prepared using a standard thin-film hydration method for liposomes. Then, cellular uptake of the loaded liposomes was assessed in vitro using fluorescent staining assays. A BBB model was constructed to investigate the capacity of the liposomes to cross the BBB in vitro, and the ability of liposomes to target the brain was observed by in vivo imaging. In addition, the neuroprotective effects of the different liposome formulations in APP/PS-1 mice were evaluated by measuring the changes in levels of oxidative, anti-inflammatory, and anti-apoptotic factors in the mice brains. RESULTS: In vitro, ApoE-Res/Sal-Lips increased the uptake of Res and Sal by bEnd.3 and N2a cells, enhanced BBB penetration, and improved transport efficiency. In vivo, the ApoE-Res/Sal-Lips were found to alleviate AD pathological symptoms, reduce learning and memory impairments, and improve brain function. CONCLUSION: ApoE-Res/Sal-Lips provide a new method for the treatment of AD.


Assuntos
Doença de Alzheimer , Glucosídeos , Doenças Neurodegenerativas , Fenóis , Camundongos , Animais , Lipossomos/farmacologia , Doença de Alzheimer/tratamento farmacológico , Resveratrol/farmacologia , Barreira Hematoencefálica , Apolipoproteínas E/farmacologia , Apolipoproteínas E/uso terapêutico
3.
Int J Mol Sci ; 24(13)2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37445887

RESUMO

In this paper, three imidazolium-based ionic liquids, viz., 1-butyl-3-undecyl imidazolium bromide ([BUIm]Br), 1-butyl-3-octyl imidazolium bromide ([BOIm]Br), and 1-butyl-3-hexadecyl imidazolium bromide ([BCIm]Br), were synthesized. Three novel microemulsions systems were constructed and then were used to recover Pd (II) from cyanide media. Key extraction parameters such as the concentration of ionic liquids (ILs), equilibration time, phase ratio (RA/O), and pH were evaluated. The [BUIm]Br/n-heptane/n-pentanol/sodium chloride microemulsion system exhibited a higher extraction percentage of Pd (II) than the [BOIm]Br/n-heptane/n-pentanol/sodium chloride and [BCIm]Br/n-heptane/n-pentanol/sodium chloride microemulsion systems. Under the optimal conditions (equilibrium time of 10 min and pH 10), the extraction percentages of these metals were all higher than 98.5% when using the [BUIm]Br/n-heptane/n-pentanol/sodium chloride microemulsion system. Pd(CN)42- was separated through a two-step stripping procedure, in which Fe (III) and Co (III) were first separated using KCl solution, then Pd(CN)42- was stripped using KSCN solution (separation factors of Pd from Fe and Co exceeded 103). After five extraction-recovery experiments, the recovery of Pd (II) through the microemulsion system remained over 90%. The Pd (II) extraction mechanism of the ionic liquid [BUIm]Br was determined to occur via anion exchange, as shown by spectral analysis (UV, FTIR), Job's method, and DFT calculations. The proposed process has potential applications for the comprehensive treatment of cyanide metallurgical wastewater.


Assuntos
Cianetos , Líquidos Iônicos , Paládio , Brometos , Cloreto de Sódio
4.
J Drug Target ; 31(6): 634-645, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37203195

RESUMO

The blood-brain barrier (BBB) is a barrier that maintains brain homeostasis, but it is also one of the major problems that must be overcome in the development of Alzheimer's disease (AD) drugs. To solve this problem, Salidroside (Sal) and Icariin (Ica), drugs with neuroprotective effects were loaded into liposomes, and the targeting molecule Angiopep-2 was modified on the surface of liposomes (Ang-Sal/Ica-Lip), so that the constructed nano-drug delivery system could effectively cross the BBB and exert anti-AD effects. The prepared liposomes exhibited ideal physicochemical properties. In vitro and in vivo targeting studies showed that Ang-Sal/Ica liposome could cross the BBB to increase drug accumulation in the brain, and increase the uptake of N2a cells and bEnd.3 cells. The pharmacodynamic analysis in vivo showed that Ang-Sal/Ica liposome could reverse neuronal and synaptic damage, inhibit neuroinflammation and oxidative stress and improve learning and cognitive function. Therefore, Ang-Sal/Ica liposome may be a promising therapeutic strategy for mitigating AD-related symptoms.


Assuntos
Doença de Alzheimer , Lipossomos , Camundongos , Animais , Lipossomos/química , Doença de Alzheimer/tratamento farmacológico , Células Endoteliais , Encéfalo , Barreira Hematoencefálica
5.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 40(3): 314-319, 2022 May 25.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-38597013

RESUMO

OBJECTIVES: The effects of using a maxillary skeletal expander (MSE) on the orbital volume and width between periorbital bones in the treatment of adult female patients with maxillary transverse deficiency (MTD) were evalua⁃ted. METHODS: A total of 20 adult female patients with MTD with an average age of (22.60±6.29) years were included in the study. The patients were treated with MSE. Cone beam computed tomography was performed before expansion (T0) and no more than 3 weeks after expansion (T1). Orbital volume and periorbital bone width were measured with Mimics 21.0 and analyzed with SPSS 20.0. Paired t-test was performed, and a P value of <0.05 indicated significant difference. RESULTS: After expansion, the orbital volume increased by (346.80±275.31) mm3 (P<0.05). The width between the right and left zygomaticomaxillary sutures increased by (1.69±0.57) mm (P<0.05), and the width between the right and left infraorbital points increased by (1.71±0.70) mm (P<0.05). However, the width between the right and left frontozygomatic sutures increased by (0.15±0.32) mm (P>0.05). Finally, the width between the right and left supraorbital points increased by (0.23±0.52) mm (P>0.05). CONCLUSIONS: The maxillary skeletal expander slightly expanded the orbital volume in the adult female patients and increased the lateral widths of the periorbital bones.

6.
Nat Commun ; 12(1): 425, 2021 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-33462243

RESUMO

Since the late 1990s, the trend of plastic waste shipment from developed to developing countries has been increasing. In 2017, China announced an unprecedented ban on its import of most plastic waste, resulting in a sharp decline in global plastic waste trade flow and changes in the treatment structure of countries, whose impacts on global environmental sustainability are enormous but yet unexamined. Here, through the life cycle assessment (LCA) method, we quantified the environmental impacts of changes in the flow patterns and treatment methods of 6 types of plastic waste in 18 countries subsequent to the ban. In the short term, the ban significantly improved four midpoint indicators of environmental impact, albeit contributed to global warming. An annual saving of about 2.35 billion euros of eco-cost was realized, which is equivalent to 56% of plastic waste global trade value in 2017. To achieve global environmental sustainability in the long run, countries should gradually realize the transition from export to domestic management, and from landfill to recycling, which would realize eco-costs savings of about 1.54-3.20 billion euros.

7.
J Hazard Mater ; 406: 124315, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33131943

RESUMO

Metal-cyanide complexes are hazardous and toxic pollutants that can accumulate in organisms, and their natural degradation is difficult. These complexes are primarily present in alkaline wastewater effluents, and an effective technique for their removal must be developed. Herein, we have successfully synthesized a novel quaternary ammonium-functionalized Zr4+ metal-organic resin (MOR) (H16[Zr6O16(MPATP)4]Cl8·xH2O, MPATP = 2-((1-methylpyridin-1-ium-2-ylmethyl)amino)-terephthalic acid), which we refer to as MOR-2-QAS. With alkali resistance, high surface area, and high anion exchange capacity, it acts by introducing positively charged pyridine into the organic ligand. The experimental results indicate that MOR-2-QAS becomes rapidly attached and efficiently removes Pt(CN)42-, Pd(CN)42-, Co(CN)63-, and Fe(CN)63-. Valuable metals (Pt(II) and Pd(II)) can be effectively recovered from the simulated wastewater containing four-component cyanide complexes via the two-step elution process. The recovery efficiency of Pt(II) and Pd(II) was higher than 90.0% after three adsorption-desorption cycles. The adsorption mechanism, which proceeded via ionic association (ion-exchange) and complied with the minimum surface charge density experiential principle, was confirmed using density functional theory. This study provides ideas for developing efficient and stable MORs to enable the simultaneous removal of multiple metal-cyanide complexes and recovery of valuable metals.

8.
ACS Omega ; 5(42): 27188-27196, 2020 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-33134679

RESUMO

Mixed [C8bet]Br/[C4mim][NTf2] ionic liquids were used as a new extraction system to extract Pd(II) from multimetal-ion solutions. The separation factors K Pd/M (M: Cu, Fe, Ni, Zn, Co) are greater than 103. Thiourea was found to be an effective stripping agent. After three cycles, the recovery efficiency was higher than 91.0%. Direct electrodeposition of palladium from the mixed ionic liquid phase was also studied. The Pd(II) complex in [C8bet]Br/[C4mim][NTf2] system was studied by cyclic voltammetry at 348 K. The results indicate the existence of three types of Pd(II) complex in the [C8bet]Br/[C4mim][NTf2] system, leading to three reductive waves. The reduction of Pd(II) to Pd(0) in this system is irreversible. A uniform black coating was obtained by constant-potential deposition at -1.7 V on a nickel foil, confirmed to be palladium metal by energy-dispersive spectrometry, X-ray photoelectron spectroscopy, and high-resolution transmission electron microscopy analyses. After three cycles of continuous extraction-electrodeposition, over 90.0% of palladium was recovered.

9.
Molecules ; 24(15)2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31370148

RESUMO

A novel functional ion-exchange/adsorption metal organic resin (MOR), TEBAC-HKUST-1, was prepared and characterized. Ethanedithiol was used as the grafting agent to introduce thiol groups onto HKUST-1, and 4-vinylbenzyl chloride was then grafted onto SH-HKUST-1 using thiol groups. Finally, the quaternary ammonium functional group was immobilized onto the carrier by performing a quaternization reaction. The structure and property of TEBAC-HKUST-1 MOR were characterized by TGA, N2 adsorption-desorption, FTIR, SEM, and XRD. TEBAC-HKUST-1 MOR was used to remove metal cyanide complexes from wastewater. The adsorption was rapid, and the metal cyanide complexes including Pt(CN)42-, Co(CN)63-, Cu(CN)32-, and Fe(CN)63- were removed in 30 min. TEBAC-HKUST-1 MOR exhibited a high stability in neutral and weak basic aqueous solutions. Furthermore, Pt(II) could be efficiently recovered through two-step elution. The recovery rate of Pt(II) for five cycles were over 92.0% in the mixture solution containing Pt(CN)42-, Co(CN)63-, Cu(CN)32-, and Fe(CN)63-. The kinetic data were best fitted with the pseudo second-order model. Moreover, the isothermal data were best fitted with the Langmuir model. The thermodynamic results show that the adsorption is a spontaneous and exothermic process. TEBAC-HKUST-1 MOR not only exhibited excellent ability for the rapid removal of metal cyanide complexes, but also provided a new idea for the extraction of noble metals from cyanide-contaminated water.


Assuntos
Cianetos/isolamento & purificação , Compostos Organometálicos/química , Águas Residuárias/química , Purificação da Água/métodos , Adsorção , Complexos de Coordenação/química , Cianetos/química , Cianetos/toxicidade , Humanos , Concentração de Íons de Hidrogênio , Resinas de Troca Iônica/química , Cinética , Paládio/química , Termodinâmica , Poluentes Químicos da Água
10.
J Cell Biol ; 218(6): 1943-1957, 2019 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-31092557

RESUMO

Metastatic prostate cancer commonly presents with targeted, bi-allelic mutations of the PTEN and TP53 tumor suppressor genes. In contrast, however, most candidate tumor suppressors are part of large recurrent hemizygous deletions, such as the common chromosome 16q deletion, which involves the AKT-suppressing phosphatase PHLPP2. Using RapidCaP, a genetically engineered mouse model of Pten/Trp53 mutant metastatic prostate cancer, we found that complete loss of Phlpp2 paradoxically blocks prostate tumor growth and disease progression. Surprisingly, we find that Phlpp2 is essential for supporting Myc, a key driver of lethal prostate cancer. Phlpp2 dephosphorylates threonine-58 of Myc, which renders it a limiting positive regulator of Myc stability. Furthermore, we show that small-molecule inhibitors of PHLPP2 can suppress MYC and kill PTEN mutant cells. Our findings reveal that the frequent hemizygous deletions on chromosome 16q present a druggable vulnerability for targeting MYC protein through PHLPP2 phosphatase inhibitors.


Assuntos
PTEN Fosfo-Hidrolase/fisiologia , Fosfoproteínas Fosfatases/fisiologia , Neoplasias da Próstata/patologia , Proteínas Proto-Oncogênicas c-myc/química , Bibliotecas de Moléculas Pequenas/farmacologia , Proteína Supressora de Tumor p53/fisiologia , Animais , Proliferação de Células , Progressão da Doença , Humanos , Masculino , Camundongos , Camundongos Knockout , Metástase Neoplásica , Fosfoproteínas Fosfatases/antagonistas & inibidores , Fosforilação , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Estabilidade Proteica , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Transdução de Sinais , Células Tumorais Cultivadas
11.
Molecules ; 23(8)2018 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-30127316

RESUMO

In this study, quaternary-ammonium-functionalized metal⁻organic frameworks (MOFs) Et-N-Cu(BDC-NH2)(DMF), were prepared, characterized, and applied for the highly effective removal of metal cyanide complexes, including Pd(CN)4²-, Co(CN)6³-, and Fe(CN)6³-. Batch studies were carried out, and the maximum adsorption capacities of Pd(II), Co(III), and Fe(III) reached 172.9, 101.0, and 102.6, respectively. Adsorption was rapid, and equilibrium was established within 30 min. Et-N-Cu(BDC-NH2)(DMF) exhibited high thermal and chemical stability. Furthermore, absorbed Pd(CN)4²- was selectively recovered by two-step elution. First, Co(CN)6³- and Fe(CN)6³- were eluted with a 1.5 mol L-¹ KCl solution. Elution rates of Co(CN)6³- and Fe(CN)6³- were greater than 98.0%, whereas the elution percentage of Pd(CN)4²- was less than 2.0%. Second, >97.0% Pd(CN)4²- on the loaded MOFs was eluted using a 2.0 mol L-¹ KI solution. The recovery rate of Pd(CN)4²- was greater than 91.0% after five testing cycles. Adsorption isotherms, kinetics models, and adsorption thermodynamics of Pd(CN)4²- on Et-N-Cu(BDC-NH2) (DMF) were also systematically investigated. The Et-N-Cu(BDC-NH2) (DMF) absorbent exhibited a rapid, excellent ability for the adsorption of metal cyanide complexes.


Assuntos
Complexos de Coordenação/química , Cianetos/química , Estruturas Metalorgânicas/química , Paládio/química , Compostos de Amônio Quaternário/química , Poluentes Químicos da Água/química , Adsorção , Cobalto/química , Complexos de Coordenação/isolamento & purificação , Cianetos/isolamento & purificação , Concentração de Íons de Hidrogênio , Ferro/química , Cinética , Ligantes , Termodinâmica , Poluentes Químicos da Água/isolamento & purificação
12.
Molecules ; 22(7)2017 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-28684696

RESUMO

Conventional separation methods are not suitable for recovering palladium present in low concentrations in ore leaching solutions. In this study, a novel isopentyl sulfide (S201)-impregnated α-MnO2 nanorod adsorbent (BISIN) was prepared, characterized, and applied for the selective adsorption and separation of palladium from the leaching liquor of ores. Batch studies were carried out, and the main adsorption parameters were systematically investigated, in addition to the relevant thermodynamic parameters, isotherms, and kinetic models. The thermodynamic parameters reflected the endothermic and spontaneous nature of the adsorption. Moreover, the experimental results indicated that the Langmuir isotherm model fits the palladium adsorption data well and the adsorption was well described by the pseudo-second-order kinetic model. The main adsorption mechanisms of palladium were elucidated at the molecular level by X-ray crystal structure analysis. Thiourea was found to be an excellent desorption agent, and the palladium-thiourea complex was also confirmed by X-ray crystal structure analysis. The results indicated that almost all of the Pd(II) (>99.0%) is adsorbed on BISIN, whereas less than 2% of the adsorbed Pt(IV), Fe3+, Cu2+, Ni2+, and Co2+ is observed under the optimum conditions. The proposed method can be used for the efficient adsorption and separation of palladium from the leaching liquor of ores.


Assuntos
Compostos de Manganês/química , Mineração , Nanopartículas/química , Óxidos/química , Paládio/isolamento & purificação , Sulfetos/química , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Cristalografia por Raios X , Concentração de Íons de Hidrogênio , Cinética , Nanopartículas/ultraestrutura , Nitrogênio/química , Porosidade , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Fatores de Tempo , Difração de Raios X
13.
J Cell Biol ; 216(3): 641-656, 2017 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-28193700

RESUMO

Phosphatase and tensin homologue (PTEN) protein levels are critical for tumor suppression. However, the search for a recurrent cancer-associated gene alteration that causes PTEN degradation has remained futile. In this study, we show that Importin-11 (Ipo11) is a transport receptor for PTEN that is required to physically separate PTEN from elements of the PTEN degradation machinery. Mechanistically, we find that the E2 ubiquitin-conjugating enzyme and IPO11 cargo, UBE2E1, is a limiting factor for PTEN degradation. Using in vitro and in vivo gene-targeting methods, we show that Ipo11 loss results in degradation of Pten, lung adenocarcinoma, and neoplasia in mouse prostate with aberrantly high levels of Ube2e1 in the cytoplasm. These findings explain the correlation between loss of IPO11 and PTEN protein in human lung tumors. Furthermore, we find that IPO11 status predicts disease recurrence and progression to metastasis in patients choosing radical prostatectomy. Thus, our data introduce the IPO11 gene as a tumor-suppressor locus, which is of special importance in cancers that still retain at least one intact PTEN allele.


Assuntos
PTEN Fosfo-Hidrolase/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Proteínas Supressoras de Tumor/metabolismo , beta Carioferinas/metabolismo , Animais , Linhagem Celular , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Células HeLa , Humanos , Neoplasias Pulmonares/metabolismo , Camundongos , Enzimas de Conjugação de Ubiquitina/metabolismo
14.
Mol Cell ; 58(2): 255-68, 2015 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-25866245

RESUMO

PTEN is proposed to function at the plasma membrane, where receptor tyrosine kinases are activated. However, the majority of PTEN is located throughout the cytoplasm. Here, we show that cytoplasmic PTEN is distributed along microtubules, tethered to vesicles via phosphatidylinositol 3-phosphate (PI(3)P), the signature lipid of endosomes. We demonstrate that the non-catalytic C2 domain of PTEN specifically binds PI(3)P through the CBR3 loop. Mutations render this loop incapable of PI(3)P binding and abrogate PTEN-mediated inhibition of PI 3-kinase/AKT signaling. This loss of function is rescued by fusion of the loop mutant PTEN to FYVE, the canonical PI(3)P binding domain, demonstrating the functional importance of targeting PTEN to endosomal membranes. Beyond revealing an upstream activation mechanism of PTEN, our data introduce the concept of PI 3-kinase signal activation on the vast plasma membrane that is contrasted by PTEN-mediated signal termination on the small, discrete surfaces of internalized vesicles.


Assuntos
PTEN Fosfo-Hidrolase/química , PTEN Fosfo-Hidrolase/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Fosfatos de Fosfatidilinositol/metabolismo , Vesículas Transportadoras/metabolismo , Animais , Sítios de Ligação , Camundongos , Microtúbulos/enzimologia , Modelos Moleculares , Células NIH 3T3 , Estrutura Secundária de Proteína , Transdução de Sinais
15.
Cancer Discov ; 5(6): 636-51, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25829425

RESUMO

UNLABELLED: We have recently recapitulated metastasis of human PTEN/TP53-mutant prostate cancer in the mouse using the RapidCaP system. Surprisingly, we found that this metastasis is driven by MYC, and not AKT, activation. Here, we show that cell-cell communication by IL6 drives the AKT-MYC switch through activation of the AKT-suppressing phosphatase PHLPP2, when PTEN and p53 are lost together, but not separately. IL6 then communicates a downstream program of STAT3-mediated MYC activation, which drives cell proliferation. Similarly, in tissues, peak proliferation in Pten/Trp53-mutant primary and metastatic prostate cancer does not correlate with activated AKT, but with STAT3/MYC activation instead. Mechanistically, MYC strongly activates the AKT phosphatase PHLPP2 in primary cells and prostate cancer metastasis. We show genetically that Phlpp2 is essential for dictating the proliferation of MYC-mediated AKT suppression. Collectively, our data reveal competition between two proto-oncogenes, MYC and AKT, which ensnarls the Phlpp2 gene to facilitate MYC-driven prostate cancer metastasis after loss of Pten and Trp53. SIGNIFICANCE: Our data identify IL6 detection as a potential causal biomarker for MYC-driven metastasis after loss of PTEN and p53. Second, our finding that MYC then must supersede AKT to drive cell proliferation points to MYC inhibition as a critical part of PI3K pathway therapy in lethal prostate cancer.


Assuntos
Genes myc , Interleucina-6/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , PTEN Fosfo-Hidrolase/deficiência , Fosfoproteínas Fosfatases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteína Supressora de Tumor p53/deficiência , Animais , Comunicação Celular/genética , Proliferação de Células , Epitélio/metabolismo , Epitélio/patologia , Deleção de Genes , Genótipo , Humanos , Neoplasias Pulmonares/secundário , Masculino , Camundongos , Mutação , Metástase Neoplásica , Neoplasias/patologia , Fosforilação , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Ligação Proteica , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Células Estromais/metabolismo
16.
Proc Natl Acad Sci U S A ; 111(38): E3957-65, 2014 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-25201979

RESUMO

Growth factor receptor levels are aberrantly high in diverse cancers, driving the proliferation and survival of tumor cells. Understanding the molecular basis for this aberrant elevation has profound clinical implications. Here we show that the pleckstrin homology domain leucine-rich repeat protein phosphatase (PHLPP) suppresses receptor tyrosine kinase (RTK) signaling output by a previously unidentified epigenetic mechanism unrelated to its previously described function as the hydrophobic motif phosphatase for the protein kinase AKT, protein kinase C, and S6 kinase. Specifically, we show that nuclear-localized PHLPP suppresses histone phosphorylation and acetylation, in turn suppressing the transcription of diverse growth factor receptors, including the EGF receptor. These data uncover a much broader role for PHLPP in regulation of growth factor signaling beyond its direct inactivation of AKT: By suppressing RTK levels, PHLPP dampens the downstream signaling output of two major oncogenic pathways, the PI3 kinase/AKT and the Rat sarcoma (RAS)/ERK pathways. Our data are consistent with a model in which PHLPP modifies the histone code to control the transcription of RTKs.


Assuntos
Receptores ErbB/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Modelos Biológicos , Proteínas Nucleares/metabolismo , Fosfoproteínas Fosfatases/metabolismo , Animais , Linhagem Celular Transformada , Receptores ErbB/genética , Camundongos , Camundongos Knockout , Proteínas Nucleares/genética , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Fosfoproteínas Fosfatases/genética , Proteína Quinase C/genética , Proteína Quinase C/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Sequências Repetitivas de Aminoácidos , Transcrição Gênica/fisiologia
17.
Clin Cancer Res ; 20(12): 3057-63, 2014 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-24928944

RESUMO

Cancer research has seen tremendous changes over the past decade. Fast progress in sequencing technology has afforded us with landmark genetic alterations, which had immediate impact on clinical science and practice by pointing to new kinase targets, such as phosphoinositide 3-kinase (PI3K), the EGF receptor, or BRAF. The PI3K pathway for growth control has emerged as a prime example for both oncogene activation and tumor suppressor loss in cancer. Here, we discuss how therapy using PI3K pathway inhibitors could benefit from information on specific phosphatases, which naturally antagonize the kinase targets. This PI3K pathway is found mutated in most cancer types, including prostate, breast, colon, and brain tumors. The tumor-suppressing phosphatases operate at two levels. Lipid-level phosphatases, such as PTEN and INPP4B, revert PI3K activity to keep the lipid second messengers inactive. At the protein level, PHLPP1/2 protein phosphatases inactivate AKT kinase, thus antagonizing mTOR complex 2 activity. However, in contrast with their kinase counterparts the phosphatases are unlikely drug targets. They would need to be stimulated by therapy and are commonly deleted and mutated in cancer. Yet, because they occupy critical nodes in preventing cancer initiation and progression, the information on their status has tremendous potential in outcome prediction, and in matching the available kinase inhibitor repertoire with the right patients. Clin Cancer Res; 20(12); 3057-63. ©2014 AACR.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias/diagnóstico , Neoplasias/tratamento farmacológico , PTEN Fosfo-Hidrolase/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Proteínas Quinases/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Humanos , PTEN Fosfo-Hidrolase/antagonistas & inibidores , Inibidores de Fosfoinositídeo-3 Quinase , Fosforilação/efeitos dos fármacos , Prognóstico
18.
Cancer Cell ; 20(2): 173-86, 2011 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-21840483

RESUMO

Hyperactivation of the PI 3-kinase/AKT pathway is a driving force of many cancers. Here we identify the AKT-inactivating phosphatase PHLPP1 as a prostate tumor suppressor. We show that Phlpp1-loss causes neoplasia and, on partial Pten-loss, carcinoma in mouse prostate. This genetic setting initially triggers a growth suppressive response via p53 and the Phlpp2 ortholog, and reveals spontaneous Trp53 inactivation as a condition for full-blown disease. Surprisingly, the codeletion of PTEN and PHLPP1 in patient samples is highly restricted to metastatic disease and tightly correlated to deletion of TP53 and PHLPP2. These data establish a conceptual framework for progression of PTEN mutant prostate cancer to life-threatening disease.


Assuntos
Mutação , Proteínas Nucleares/fisiologia , PTEN Fosfo-Hidrolase/genética , Fosfoproteínas Fosfatases/fisiologia , Neoplasias da Próstata/patologia , Progressão da Doença , Humanos , Masculino , PTEN Fosfo-Hidrolase/metabolismo , Neoplasias da Próstata/metabolismo
19.
BMC Cancer ; 11: 199, 2011 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-21612665

RESUMO

BACKGROUND: Amplification of 3q26 is one of the most frequent genetic alterations in many human malignancies. Recently, we isolated a novel oncogene eIF-5A2 within the 3q26 region. Functional study has demonstrated the oncogenic role of eIF-5A2 in the initiation and progression of human cancers. In the present study, we aim to investigate the physiological and pathological effect of eIF-5A2 in an eIF-5A2 transgenic mouse model. METHODS: An eIF-5A2 transgenic mouse model was generated using human eIF-5A2 cDNA. The eIF-5A2 transgenic mice were characterized by histological and immunohistochemistry analyses. The aging phenotypes were further characterized by wound healing, bone X-ray imaging and calcification analysis. Mouse embryo fibroblasts (MEF) were isolated to further investigate molecular mechanism of eIF-5A2 in aging. RESULTS: Instead of resulting in spontaneous tumor formation, overexpression of eIF-5A2 accelerated the aging process in adult transgenic mice. This included decreased growth rate and body weight, shortened life span, kyphosis, osteoporosis, delay of wound healing and ossification. Investigation of the correlation between cellular senescence and aging showed that cellular senescence is not required for the aging phenotypes in eIF-5A2 mice. Interestingly, we found that activation of eIF-5A2 repressed p19 level and therefore destabilized p53 in transgenic mouse embryo fibroblast (MEF) cells. This subsequently allowed for the accumulation of chromosomal instability, such as errors in cell dividing during metaphase and anaphase. Additionally, a significantly increase in number of aneuploidy cells (p < 0.05) resulted from an increase in the incidences of misaligned and lagging chromosomal materials, anaphase bridges, and micronuclei in the transgenic mice. CONCLUSION: These observations suggest that eIF-5A2 mouse models could accelerate organismal aging by increasing chromosome instability.


Assuntos
Envelhecimento/genética , Instabilidade Cromossômica/genética , Expressão Gênica/genética , Fatores de Iniciação de Peptídeos/genética , Fatores de Iniciação de Peptídeos/metabolismo , Animais , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/patologia , Transformação Celular Neoplásica/genética , Senescência Celular/genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Masculino , Camundongos , Camundongos Transgênicos , Fenótipo , Gravidez , Radiografia
20.
PLoS One ; 4(8): e6727, 2009 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-19701453

RESUMO

BACKGROUND: Amplification of 1q21 is the most frequent genetic alteration in hepatocellular carcinoma (HCC), which was detected in 58-78% of primary HCC cases by comparative genomic hybridization (CGH). Using chromosome microdissection/hybrid selection approach we recently isolated a candidate oncogene CHD1L from 1q21 region. Our previous study has demonstrated that CHD1L had strong oncogenic ability, which could be effectively suppressed by siRNA against CHD1L. The molecular mechanism of CHD1L in tumorigenesis has been associated with its role in promoting cell proliferation. METHODOLOGY/PRINCIPAL FINDINGS: To further investigate the in vivo oncogenic role of CHD1L, CHD1L ubiquitous-expression transgenic mouse model was generated. Spontaneous tumor formations were found in 10/41 (24.4%) transgenic mice, including 4 HCCs, but not in their 39 wild-type littermates. In addition, alcohol intoxication was used to induce hepatocyte pathological lesions and results found that overexpression of CHD1L in hepatocytes could promote tumor susceptibility in CHD1L-transgenic mice. To address the mechanism of CHD1L in promoting cell proliferation, DNA content between CHD1L-transgenic and wildtype mouse embryo fibroblasts (MEFs) was compared by flow cytometry. Flow cytometry results found that CHD1L could facilitate DNA synthesis and G1/S transition through the up-regulation of Cyclin A, Cyclin D1, Cyclin E, CDK2, and CDK4, and down-regulation of Rb, p27(Kip1), and p53. CONCLUSION/SIGNIFICANCE: Taken together, our data strongly support that CHD1L is a novel oncogene and plays an important role in HCC pathogenesis.


Assuntos
DNA Helicases/fisiologia , Proteínas de Ligação a DNA/fisiologia , Neoplasias Hepáticas Experimentais/genética , Animais , Sequência de Bases , Ciclo Celular/fisiologia , Mapeamento Cromossômico , Cocarcinogênese , DNA Helicases/genética , Primers do DNA , Proteínas de Ligação a DNA/genética , Etanol/toxicidade , Citometria de Fluxo , Immunoblotting , Neoplasias Hepáticas Experimentais/induzido quimicamente , Neoplasias Hepáticas Experimentais/patologia , Camundongos , Camundongos Transgênicos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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