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1.
NPJ Precis Oncol ; 8(1): 189, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39237596

RESUMO

Pathological complete response (pCR) serves as a critical measure of the success of neoadjuvant chemotherapy (NAC) in breast cancer, directly influencing subsequent therapeutic decisions. With the continuous advancement of artificial intelligence, methods for early and accurate prediction of pCR are being extensively explored. In this study, we propose a cross-modal multi-pathway automated prediction model that integrates temporal and spatial information. This model fuses digital pathology images from biopsy specimens and multi-temporal ultrasound (US) images to predict pCR status early in NAC. The model demonstrates exceptional predictive efficacy. Our findings lay the foundation for developing personalized treatment paradigms based on individual responses. This approach has the potential to become a critical auxiliary tool for the early prediction of NAC response in breast cancer patients.

2.
Phys Med Biol ; 69(15)2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38861995

RESUMO

We previously proposed range-guided adaptive proton therapy (RGAPT) that uses mid-range treatment beams as probing beams and intra-fractionated range measurements for online adaptation. In this work, we demonstrated experimental verification and reported the dosimetric accuracy for RGAPT. A STEEV phantom was used for the experiments, and a 3 × 3 × 3 cm3cube inside the phantom was assigned to be the treatment target. We simulated three online range shift scenarios: reference, overshoot, and undershoot, by placing upstream Lucite sheets, 4, 0, and 8 that corresponded to changes of 0, 6.8, and -6.8 mm, respectively, in water-equivalent path length. The reference treatment plan was to deliver single-field uniform target doses in pencil beam scanning mode and generated on the Eclipse treatment planning system. Different numbers of mid-range layers, including single, three, and five layers, were selected as probing beams to evaluate beam range (BR) measurement accuracy in positron emission tomography (PET). Online plans were modified to adapt to BR shifts and compensate for probing beam doses. In contrast, non-adaptive plans were also delivered and compared to adaptive plans by film measurements. The mid-range probing beams of three (5.55MU) and five layers (8.71MU) yielded accurate range shift measurements in 60 s of PET acquisition with uncertainty of 0.5 mm while the single-layer probing (1.65MU) was not sufficient for measurements. The adaptive plans achieved an average gamma (2%/2 mm) passing rate of 95%. In contrast, the non-adaptive plans only had an average passing rate of 69%. RGAPT planning and delivery are feasible and verified by the experiments. The probing beam delivery, range measurements, and adaptive planning and delivery added a small increase in treatment delivery workflow time but resulted in substantial dose improvement. The three-layer mid-range probing was most suitable considering the balance of high range measurement accuracy and the low number of probing beam layers.


Assuntos
Imagens de Fantasmas , Terapia com Prótons , Planejamento da Radioterapia Assistida por Computador , Terapia com Prótons/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Humanos , Fracionamento da Dose de Radiação , Radioterapia Guiada por Imagem/métodos , Radiometria
3.
Phys Med Biol ; 69(15)2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38861997

RESUMO

Objective.Develop a prototype on-line positron emission tomography (PET) scanner and evaluate its capability of on-line imaging and intra-fractionated proton-induced radioactivity range measurement.Approach.Each detector consists of 32 × 32 array of 2 × 2 × 30 mm3Lutetium-Yttrium Oxyorthosilicate scintillators with single-scintillator-end readout through a 20 × 20 array of 3 × 3 mm2Silicon Photomultipliers. The PET can be configurated with a full-ring of 20 detectors for conventional PET imaging or a partial-ring of 18 detectors for on-line imaging and range measurement. All detector-level readout and processing electronics are attached to the backside of the system gantry and their output signals are transferred to a field-programable-gate-array based system electronics and data acquisition that can be placed 2 m away from the gantry. The PET imaging performance and radioactivity range measurement capability were evaluated by both the offline study that placed a radioactive source with known intensity and distribution within a phantom and the online study that irradiated a phantom with proton beams under different radiation and imaging conditions.Main results.The PET has 32 cm diameter and 6.5 cm axial length field-of-view (FOV), ∼2.3-5.0 mm spatial resolution within FOV, 3% sensitivity at the FOV center, 18%-30% energy resolution, and ∼9 ns coincidence time resolution. The offline study shows the PET can determine the shift of distal falloff edge position of a known radioactivity distribution with the accuracy of 0.3 ± 0.3 mm even without attenuation and scatter corrections, and online study shows the PET can measure the shift of proton-induced positron radioactive range with the accuracy of 0.6 ± 0.3 mm from the data acquired with a short-acquisition (60 s) and low-dose (5 MU) proton radiation to a human head phantom.Significance.This study demonstrated the capability of intra-fractionated PET imaging and radioactivity range measurement and will enable the investigation on the feasibility of intra-fractionated, range-shift compensated adaptive proton therapy.


Assuntos
Imagens de Fantasmas , Tomografia por Emissão de Pósitrons , Terapia com Prótons , Radioterapia Guiada por Imagem , Terapia com Prótons/instrumentação , Terapia com Prótons/métodos , Tomografia por Emissão de Pósitrons/instrumentação , Radioterapia Guiada por Imagem/métodos , Radioterapia Guiada por Imagem/instrumentação , Humanos , Fracionamento da Dose de Radiação
4.
J Neuroinflammation ; 21(1): 140, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38807233

RESUMO

BACKGROUND: Perihematomal edema (PHE) after post-intracerebral hemorrhage (ICH) has complex pathophysiological mechanisms that are poorly understood. The complicated immune response in the post-ICH brain constitutes a crucial component of PHE pathophysiology. In this study, we aimed to characterize the transcriptional profiles of immune cell populations in human PHE tissue and explore the microscopic differences between different types of immune cells. METHODS: 9 patients with basal ganglia intracerebral hemorrhage (hematoma volume 50-100 ml) were enrolled in this study. A multi-stage profile was developed, comprising Group1 (n = 3, 0-6 h post-ICH, G1), Group2 (n = 3, 6-24 h post-ICH, G2), and Group3 (n = 3, 24-48 h post-ICH, G3). A minimal quantity of edematous tissue surrounding the hematoma was preserved during hematoma evacuation. Single cell RNA sequencing (scRNA-seq) was used to map immune cell populations within comprehensively resected PHE samples collected from patients at different stages after ICH. RESULTS: We established, for the first time, a comprehensive landscape of diverse immune cell populations in human PHE tissue at a single-cell level. Our study identified 12 microglia subsets and 5 neutrophil subsets in human PHE tissue. What's more, we discovered that the secreted phosphoprotein-1 (SPP1) pathway served as the basis for self-communication between microglia subclusters during the progression of PHE. Additionally, we traced the trajectory branches of different neutrophil subtypes. Finally, we also demonstrated that microglia-produced osteopontin (OPN) could regulate the immune environment in PHE tissue by interacting with CD44-positive cells. CONCLUSIONS: As a result of our research, we have gained valuable insight into the immune-microenvironment within PHE tissue, which could potentially be used to develop novel treatment modalities for ICH.


Assuntos
Edema Encefálico , Hemorragia Cerebral , Progressão da Doença , Análise de Sequência de RNA , Análise de Célula Única , Humanos , Edema Encefálico/imunologia , Edema Encefálico/patologia , Edema Encefálico/genética , Edema Encefálico/metabolismo , Edema Encefálico/etiologia , Hemorragia Cerebral/imunologia , Hemorragia Cerebral/patologia , Hemorragia Cerebral/genética , Masculino , Feminino , Pessoa de Meia-Idade , Análise de Sequência de RNA/métodos , Idoso , Hematoma/patologia , Hematoma/imunologia , Hematoma/genética
5.
ACS Appl Mater Interfaces ; 16(14): 17715-17727, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38551105

RESUMO

To ensure safety and efficiency in the production and transportation of fuel oil, there is an urgent demand to develop intelligent emulsifiers to deal with this challenge. Fe3O4@PDA-P(NIPAM-b-MAA-b-LMA) (MNPDNML) microspheres were prepared by modifying polydopamine and the triblock polymer brush P(NIPAM-b-MAA-b-LMA) on the surface of Fe3O4 nanoparticles via oxidative autopolymerization and SI-RAFT polymerization. Therefore, the MNPDNML microspheres exhibited sensitive stimulus-responsive behavior to pH, temperature, near-infrared (NIR) laser radiation, and magnetic fields. The stability state of the emulsion could be modulated by changing pH, temperature, magnetic field, and NIR radiation, and the reversible switching of emulsification/breaking behavior could be reached at least 10 times. This "intelligent emulsifier" exhibited high emulsification efficiency, long-term stability, and on-demand emulsification/breaking properties. It was notable that MNPDNML microspheres showed excellent emulsification ability for olive oil, kerosene, gasoline, and crude oil, which allowed the material to be widely used in the controlled transportation and separation of fuel oil.

6.
Tomography ; 9(2): 567-578, 2023 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-36961005

RESUMO

We have integrated a compact and lightweight PET with an existing CT image-guided small animal irradiator to enable practical onboard PET/CT image-guided preclinical radiation therapy (RT) research. The PET with a stationary and full-ring detectors has ~1.1 mm uniform spatial resolution over its imaging field-of-view of 8.0 cm diameter and 3.5 cm axial length and was mechanically installed inside the irradiator in a tandem configuration with CT and radiation unit. A common animal bed was used for acquiring sequential dual functional and anatomical images with independent PET and CT control and acquisition systems. The reconstructed dual images were co-registered based on standard multi-modality image calibration and registration processes. Phantom studies were conducted to evaluate the integrated system and dual imaging performance. The measured mean PET/CT image registration error was ~0.3 mm. With one-bed and three-bed acquisitions, initial tumor focused and whole-body [18F]FDG animal images were acquired to test the capability of onboard PET/CT image guidance for preclinical RT research. Overall, the results have shown that integrated PET/CT/RT can provide advantageous and practical onboard PET/CT image to significantly enhance the accuracy of tumor delineation and radiation targeting that should enhance the existing and enable new and potentially breakthrough preclinical RT research and applications.


Assuntos
Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Radioterapia (Especialidade) , Animais , Fluordesoxiglucose F18 , Imagens de Fantasmas
7.
Phys Med Biol ; 67(11)2022 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-35523154

RESUMO

Purpose.Although positron emission tomography (PET) can provide a functional image of static tumors for RT guidance, it's conventionally very challenging for PET to track a moving tumor in real-time with a multiple frame/s sampling rate. In this study, we developed a novel method to enable PET based three-dimension (3D) real-time marker-less tumor tracking (RMTT) and demonstrated its feasibility with a simulation study.Methods.For each line-of-response (LOR) acquired, its positron-electron annihilation position is calculated based on the time difference between the two gamma interactions detected by the TOF PET detectors. The accumulation of these annihilation positions from data acquired within a single sampling frame forms a coarsely measured 3D distribution of positron-emitter radiotracer uptakes of the lung tumor and other organs and tissues (background). With clinically relevant tumor size and sufficient differential radiotracer uptake concentrations between the tumor and background, the high-uptake tumor can be differentiated from the surrounding low-uptake background in the measured distribution of radiotracer uptakes. With a volume-of-interest (VOI) that closely encloses the tumor, the count-weighted centroid of the annihilation positions within the VOI can be calculated as the tumor position. All these data processes can be conducted online. The feasibility of the new method was investigated with a simulated cardiac-torso digital phantom and stationary dual-panel TOF PET detectors to track a 28 mm diameter lung tumor with a 4:1 tumor-to-background18FDG activity concentration ratio.Results.The initial study shows TOF PET based RMTT can achieve <2.0 mm tumor tracking accuracy with 5 frame s-1sampling rate under the simulated conditions. In comparison, using reconstructed PET images to track a similar size tumor would require >30 s acquisition time to achieve the same tracking accuracy.Conclusion.With the demonstrated feasibility, the new method may enable TOF PET based RMTT for practical RT applications.


Assuntos
Algoritmos , Neoplasias Pulmonares , Simulação por Computador , Humanos , Processamento de Imagem Assistida por Computador , Imagens de Fantasmas , Tomografia por Emissão de Pósitrons
8.
Phys Med Biol ; 66(21)2021 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-34592731

RESUMO

OBJECTIVE: In contrast to clinical radiation therapy (RT) that ubiquitously uses PET/CT image to accurately guide RT, all current commercial animal irradiators can only provide CT image-guided preclinical RT that severely limits their capability for preclinical and compatibility for translational radiation oncology research. To address this problem, we have developed a compact and lightweight PET with uniform, high spatial resolution that is suited to be installed inside an existing animal irradiator for potential onboard PET/CT image-guided preclinical RT research. APPROACH: The design focused on the balance of achieving sufficient imaging performance for practical preclinical RT guidance with constrained size and weight. The detector head consists of a ring of 12 detector panels in a dodecagon configuration and 12 front-end electronics boards that are closely attached to the detector panels. The overall size and weight of the detector head are 33.0 cm diameter, 11.0 cm axial length and ∼6.5 kg weight that can be installed inside an existing irradiator. Each detector panel has a 30 × 30 array of 1 × 1 × 20 mm3LYSO scintillators with depth-of-interaction (DOI) measurement. The front-end electronics boards process and convert detected signals to digital signals and transfer them to system electronics and data acquisition located outside the irradiator through low-voltage-differential-signaling cables. MAIN RESULTS: The typical energy, DOI and coincidence timing resolutions are around 22.1%, 3.1 mm, and 1.92 ns. The imaging field-of-view (FOV) is 8.0 cm diameter and 3.5 cm axial length. The performance evaluations show a 1.8% sensitivity at the center FOV, uniform ∼1.1 mm resolution within 6 cm diameter FOV, and all rods of 1.0 mm diameter can be clearly resolved from the image of an ultra-micro hot-rods phantom. SIGNIFICANCE: Overall, this compact and lightweight PET has demonstrated its designed capability and performance sufficient for providing onboard functional/biological/molecular image to guide the preclinical RT research.


Assuntos
Radioterapia (Especialidade) , Radioterapia Guiada por Imagem , Animais , Desenho de Equipamento , Imagens de Fantasmas , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Tomografia por Emissão de Pósitrons/métodos , Radioterapia Guiada por Imagem/veterinária
9.
ACS Appl Mater Interfaces ; 13(17): 20125-20136, 2021 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-33890784

RESUMO

It is still a big challenge to effectively suppress dendrite growth, which increases the safety and life of lithium-metal-based high energy/power density batteries. To address such issues, herein we design and fabricate a lithiophilic VN@N-rGO as a multifunctional layer on commercial polypropylene (PP) separator, which is constructed by a thin N-rGO nanosheet-wrapped VN nanosphere with a uniform pore distribution, relatively high lithium ionic conductivity, excellent electrolyte wettability, additional lithium-ion diffusion pathways, high mechanical strength, and reliable thermal stability, which are beneficial to regulate the interfacial lithium ionic flux, resulting in the formation of a stable and homogeneous current density distribution on Li-metal electrodes and hard modified separators that can resist dendrites piercing. Consequently, the growth of Li dendrite is effectively suppressed, and the cycle stability of lithium-metal batteries is significantly improved. In addition, even at a high current density of 10 mA cm-2 and cutoff areal capacity of 5 mAh cm-2, the Li|Li symmetric batteries with VN@N-rGO/PP separators still work very well even over 2500 h, exhibiting ultrahigh cycling stability. This work presents rational design ideas and a facile fabrication strategy of a lithiophilic 3D porous multifunctional interlayer for dendrite-free and ultrastable lithium-metal-based batteries.

10.
Acta Neurochir (Wien) ; 163(2): 563-571, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33006072

RESUMO

BACKGROUND: Cerebral hyperperfusion syndrome (CHS) is a common complication after direct bypass surgery in patients with Moyamoya disease (MMD). Since preventive measures may be inadequate, we assessed whether the blood flow difference between the superficial temporal artery (STA) and recipient vessels (△BF) and the direct perfusion range (DPR) are related to CHS. METHODS: We measured blood flow in the STA and recipient blood vessels before bypass surgery by transit-time probe to calculate △BF. Perfusion changes around the anastomosis before and after bypass were analyzed with FLOW800 to obtain DPR. Multiple factors, such as △BF, DPR, and postoperative CHS, were analyzed using binary logistic regression. RESULTS: Forty-one patients with MMD who underwent direct bypass surgery were included in the study. Postoperative CHS symptoms occurred in 13/41 patients. △BF and DPR significantly differed between the CHS and non-CHS groups. The optimal receiver operating characteristic (ROC) curve cut-off value was 31.4 ml/min for ΔBF, and the area under the ROC curve (AUC) was 0.695 (sensitivity 0.846, specificity 0.500). The optimal cut-off value was 3.5 cm for DPR, and the AUC was 0.702 (sensitivity 0.615, specificity 0.750). CONCLUSION: Postoperative CHS is caused by multiple factors. △BF is a risk factor for CHS while DPR is a protective factor against CHS.


Assuntos
Encéfalo/irrigação sanguínea , Revascularização Cerebral/efeitos adversos , Complicações Intraoperatórias/etiologia , Doença de Moyamoya/cirurgia , Traumatismo por Reperfusão/etiologia , Adulto , Anastomose Cirúrgica/efeitos adversos , Circulação Cerebrovascular , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Software , Síndrome , Artérias Temporais/cirurgia , Ultrassonografia
12.
Artif Cells Nanomed Biotechnol ; 47(1): 2882-2890, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31307224

RESUMO

Background: Histone H1.5 has been considered as a novel cancer marker as its expression is associated with various human cancers. The objective of this study was to explore the effects of H1.5 phosphorylation in Ras-driven growth and migration of glioma cells. Methods: The plasmids for expression of wide-type of Ras or RasG12V/Y40C were transfected into A172 cells. The expression levels of phosphorylated AKT and H1.5T10ph were tested by Western blot. The effects of H1.5T10ph on A172 cells growth and migration were determined by MTT, soft-agar colony formation, and transwell assay. qRT-PCR and ChIP assay were utilized to assess the role of H1.5T10ph in the transcription of Ras downstream genes. Besides, qRT-PCR and Western blot analysis were carried out to reveal the enzymes which were responsible for phosphorylating H1.5. Results: H1.5T10ph was down-regulated by Ras mutation, which accompanied by the activation of AKT signaling. Ras-driven A172 cells growth and migration were inhibited when H1.5T10ph was overexpressed. Additionally, H1.5T10ph was able to regulate the transcription of Ras downstream genes, including CYR61, IGFBP3, WNT16B, NT5E, GDF15, and CARD16. Further experiments revealed that Ras-AKT signaling repressed H1.5T10ph expression through degradation of GSK3, and the degradation was dependent on MDM2 mediation. Conclusion: Ras-AKT signaling driven the growth and migration of glioma cells possibly through repressing the phosphorylation of H1.5 at threonine 10. Ras-AKT activation repressed H1.5T10ph through MDM2-dependent degradation of GSK3. The findings provide a better understanding of Ras's oncogenic functions which further suggest Ras as a therapeutic target for glioma.


Assuntos
Progressão da Doença , Glioma/patologia , Quinase 3 da Glicogênio Sintase/metabolismo , Histonas/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Treonina/metabolismo , Proteínas ras/metabolismo , Carcinogênese , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Histonas/química , Humanos , Fosforilação , Proteólise , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Transdução de Sinais , Transcrição Gênica
13.
Life Sci ; 225: 55-63, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30946839

RESUMO

BACKGROUND/AIMS: Acetylation of H4 at lysine 16 (H4K16ac) has been well-characterized as an acetylated mark, and the expression of which is closely associated with the tumorigenesis of human cancers. This study aimed to reveal whether KRas mutation drives the initiation and progression of glioma via modulation of H4 acetylation. METHODS: Changes of H4K16 acetylation in human glioblastoma A172 cells following transfection with a plasmid for expression of mutant KRas were tested by western blot analysis. MTT assay, transwell assay, soft-agar colony formation assay, RT-PCR and chromatin immunoprecipitation were carried out to evaluate the effect of H4K16ac on A172 cells growth and migration. Furthermore, the enzymes participating in the deacetylation of H4K16ac were studied by using RT-PCR and western blot analysis. RESULTS: H4K16ac was found to be deacetylated by KRas-ERK1/2 activation. H4K16Q (a plasmid for mimicking H4K16ac) repressed A172 cells viability, colony formation, and migratory capacity. Besides, H4K16ac was capable of regulating the transcription of several ERK1/2 pathway downstream genes. KRas-ERK1/2 signaling repressed H4 acetylation at K16 via modulation of a histone deacetylase Sirt2, as well as a histone acetyl-transferase TIP60. Moreover, KRas-ERK1/2 inhibited TIP60 via an MDM2-dependnet fashion. CONCLUSION: Our results suggest that activation of KRas-ERK1/2 signaling participates in the onset and progression of glioma at least partially through modulating acetylation of H4 at K16. KRas-ERK1/2 signaling mediates the acetylation of H4K16 via Sirt2 and MDM2-dependnet degeneration of TIP60.


Assuntos
Glioma/patologia , Histonas/metabolismo , Lisina/química , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Acetilação , Apoptose , Movimento Celular , Proliferação de Células , Glioma/genética , Glioma/metabolismo , Histonas/genética , Humanos , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/genética , Processamento de Proteína Pós-Traducional , Proteínas Proto-Oncogênicas p21(ras)/genética , Transdução de Sinais , Células Tumorais Cultivadas
15.
Org Lett ; 19(18): 4826-4829, 2017 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-28862455

RESUMO

A nickel-mediated asymmetric allylic alkylation reaction between imidazole-modified ketones and nitroallylic acetates is presented. This reaction is catalyzed by a simple chiral diamine-nickel catalyst under mild conditions and leads to a series of novel enantioenriched α-allylic adducts in moderate to good yields with excellent enantioselectivities. Furthermore, transformation of the allylic adducts could smoothly lead to chiral γ-nitro-esters containing three continuous stereocenters in good yields.

16.
Neuro Oncol ; 19(12): 1628-1639, 2017 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-28575494

RESUMO

BACKGROUND: Golgi phosphoprotein 3 (GOLPH3) is associated with worse prognosis of gliomas, but its role and mechanism in glioma progression remain largely unknown. This study aimed to explore the role and mechanism of GOLPH3 in glioma progression. METHODS: The expression of GOLPH3 in glioma tissues was detected by quantitative PCR, immunoblotting, and immunohistochemistry. GOLPH3's effect on glioma progression was examined using cell growth assays and an intracranial glioma model. The effect of GOLPH3 on epidermal growth factor receptor (EGFR) stability, endocytosis, and degradation was examined by immunoblotting and immunofluorescence. The activity of Rab5 was checked by glutathione S-transferase pulldown assay. RESULTS: GOLPH3 was upregulated in gliomas, and its downregulation inhibited glioma cell proliferation both in vitro and in vivo. Furthermore, GOLPH3 depletion dampened EGFR signaling by enhancing EGFR endocytosis, driving EGFR into late endosome and promoting lysosome-mediated degradation. Interestingly, GOLPH3 bound to Rab5 and GOLPH3 downregulation promoted the activation of Rab5. In addition, Rab5 depletion abolished the effect of GOLPH3 on EGFR endocytosis and degradation. CONCLUSION: Our results imply that GOLPH3 promotes glioma cell proliferation via inhibiting Rab5-mediated endocytosis and degradation of EGFR, thereby activating the phosphatidylinositol-3 kinase (PI3K)-Akt-mammalian target of rapamycin (mTOR) signaling pathway. We find a new mechanism by which GOLPH3 promotes tumor progression through regulating cell surface receptor trafficking. Extensive and intensive understanding of the role of GOLPH3 in glioma progression may provide an opportunity to develop a novel molecular therapeutic target for gliomas.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/patologia , Endocitose/fisiologia , Receptores ErbB/metabolismo , Glioma/patologia , Proteínas de Membrana/metabolismo , Proteínas rab5 de Ligação ao GTP/metabolismo , Animais , Biomarcadores Tumorais/genética , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Progressão da Doença , Receptores ErbB/genética , Glioma/genética , Glioma/metabolismo , Humanos , Proteínas de Membrana/genética , Camundongos Nus , Prognóstico , Transdução de Sinais , Proteínas rab5 de Ligação ao GTP/genética
17.
Chemistry ; 23(29): 6974-6978, 2017 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-28470882

RESUMO

A nickel-catalyzed asymmetric oxazole-forming Ugi reaction of C,N-cyclic azomethine imines and isonitriles is disclosed. The reported protocol proceeds smoothly, and gives the corresponding adducts, which contain two important pharmaceutically active ring-systems (tetrahydroquinoline and oxazole rings), in good yields and excellent enantioselectivities by employing an easily accessible chiral diamine as a ligand. This simple and efficient strategy provides easy access to a series of C1-substituted aryl tetrahydroisoquinolines.

18.
Org Lett ; 17(12): 3004-7, 2015 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-26030403

RESUMO

3-Isothiocyanato oxindoles have been successfully applied to an asymmetric formal [3 + 3] cycloaddition reaction with aziridines for the first time. The reaction was efficiently mediated by an in situ generated magnesium catalyst employing (R)-3,3'-fluorous-BINOL as a simple chiral ligand. Serials of polycyclic frameworks could be obtained after a ring-closing step. The enantioenriched ring-opening product was also utilized to modified amino acids, peptides, and bifunctional organocatalyst.


Assuntos
Aminoácidos/química , Aziridinas/química , Indóis/química , Isotiocianatos/química , Naftóis/química , Peptídeos/química , Catálise , Ligantes , Estrutura Molecular , Oxindóis , Estereoisomerismo
19.
Biochem Biophys Res Commun ; 433(3): 338-44, 2013 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-23500462

RESUMO

Golgi phosphoprotein 3 (GOLPH3) has been reported to be involved in the development of several human cancers. However, the biological significance of GOLPH3 in glioma progression remains largely unknown. In this study, we report, for the first time, that downregulation of GOLPH3 led to clear reductions in glioma cell migration and invasion. In addition, downregulation of GOLPH3 inhibited the expression of the small GTPase RhoA as well as cytoskeletal reorganization, which are both required for glioma cell migration. Furthermore, we found that the observed reductions in glioma cell migration and RhoA level could be rescued by RhoA overexpression. Taken together, these results show that GOLPH3 contributes to the motility of glioma cells by regulating the expression of RhoA.


Assuntos
Neoplasias Encefálicas/genética , Regulação Neoplásica da Expressão Gênica , Glioma/genética , Proteínas de Membrana/genética , Proteína rhoA de Ligação ao GTP/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Citoesqueleto/metabolismo , Citoesqueleto/patologia , Cultura em Câmaras de Difusão , Glioma/metabolismo , Glioma/patologia , Humanos , Proteínas de Membrana/metabolismo , Invasividade Neoplásica , Plasmídeos , Transdução de Sinais , Transfecção , Proteína rhoA de Ligação ao GTP/metabolismo
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