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1.
Cancer Immunol Immunother ; 73(7): 122, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38714539

RESUMO

Neuroblastoma (NB) is the most common and deadliest extracranial solid tumor in children. Targeting tumor-associated macrophages (TAMs) is a strategy for attenuating tumor-promoting states. The crosstalk between cancer cells and TAMs plays a pivotal role in mediating tumor progression in NB. The overexpression of Hexokinase-3 (HK3), a pivotal enzyme in glucose metabolism, has been associated with poor prognosis in NB patients. Furthermore, it correlates with the infiltration of M2-like macrophages within NB tumors, indicating its significant involvement in tumor progression. Therefore, HK3 not only directly regulates the malignant biological behaviors of tumor cells, such as proliferation, migration, and invasion, but also recruits and polarizes M2-like macrophages through the PI3K/AKT-CXCL14 axis in neuroblastoma. The secretion of lactate and histone lactylation alterations within tumor cells accompanies this interaction. Additionally, elevated expression of HK3 in M2-TAMs was found at the same time. Modulating HK3 within M2-TAMs alters the biological behavior of tumor cells, as demonstrated by our in vitro studies. This study highlights the pivotal role of HK3 in the progression of NB malignancy and its intricate regulatory network with M2-TAMs. It establishes HK3 as a promising dual-functional biomarker and therapeutic target in combating neuroblastoma.


Assuntos
Hexoquinase , Neuroblastoma , Macrófagos Associados a Tumor , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Humanos , Hexoquinase/metabolismo , Macrófagos Associados a Tumor/metabolismo , Macrófagos Associados a Tumor/imunologia , Proliferação de Células , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Fosfatidilinositol 3-Quinases/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Quimiocinas CXC/metabolismo , Animais , Microambiente Tumoral/imunologia
2.
J Am Chem Soc ; 145(10): 5930-5940, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36867864

RESUMO

The crossing of blood-brain barrier (BBB) is essential for glioblastoma (GBM) therapy, and homotypic targeting is an effective strategy to achieve BBB crossing. In this work, GBM patient-derived tumor cell membrane (GBM-PDTCM) is prepared to cloak gold nanorods (AuNRs). Relying on the high homology of the GBM-PDTCM to the brain cell membrane, GBM-PDTCM@AuNRs realize efficient BBB crossing and selective GBM targeting. Meanwhile, owing to the functionalization of Raman reporter and lipophilic fluorophore, GBM-PDTCM@AuNRs are able to generate fluorescence and Raman signals at GBM lesion, and almost all tumor can be precisely resected in 15 min by the guidance of dual signals, ameliorating the surgical treatment for advanced GBM. In addition, photothermal therapy for orthotopic xenograft mice is accomplished by intravenous injection of GBM-PDTCM@AuNRs, doubling the median survival time of the mice, which improves the nonsurgical treatment for early GBM. Therefore, benefiting from homotypic membrane-enhanced BBB crossing and GBM targeting, all-stage GBM can be treated with GBM-PDTCM@AuNRs in distinct ways, providing an alternative idea for the therapy of tumor in the brain.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Humanos , Animais , Camundongos , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Barreira Hematoencefálica/metabolismo , Terapia Fototérmica , Membrana Celular/metabolismo , Linhagem Celular Tumoral , Neoplasias Encefálicas/tratamento farmacológico
3.
Contrast Media Mol Imaging ; 2022: 3265342, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35833067

RESUMO

Objective: To investigate the significance of PAX8-PPARγ expression in thyroid cancer and the application of a PAX8-PPARγ-targeted ultrasound contrast agent in the early diagnosis of thyroid cancer. Methods: In this study, the expression of PAX8-PPARγ in thyroid cancer tissues, paracancer groups, and normal thyroid tissues was detected by western and immunohistochemical techniques; the effects of PAX8-PPARγ expression inhibition on thyroid cancer cell growth, clonogenic ability, and antiapoptosis were examined. The terminal carboxylactic acid/hydroxyacetic acid copolymer (PLGA-COOH) nanoparticles were prepared by the double emulsification solvent volatilization method. The in vitro cytotoxicity of the targeted contrast agent was detected by MTS and other methods; LD50 was used to evaluate its short-term in vivo toxicity after intraperitoneal injection in mice. Results: PAX8-PPARγ expression was significantly increased in thyroid cancer tissues, and the expression level of PAX8-PPARγ was closely correlated with TNM staging and lymph node metastasis (P < 0.05). In addition, PAX8-PPARγ was also expressed at high levels in thyroid cancer cell lines relative to normal thyroid cells. MTS experiments showed that the PAX8-PPARγ-targeted ultrasound nanocontrast agent had no significant toxic side effects on thyroid cells; countess observed that the contrast agent had no effect on cell survival and mortality; the LD50 assay showed that the targeted contrast agent had a wide safety range. Western blot showed the expression of caspase-3, BAX, and Bcl-2 in thyroid cancer cells, indicating that the nanocontrast agent has a good biosafety. In vitro targeting experiments showed that there were more nanospheres aggregated around the cells in the targeted contrast group. In vivo targeting imaging of nude mice revealed that the ultrasound signal was significantly enhanced in the targeted group compared with the nontargeted group after 20 min of LIFU irradiation. Conclusion: PAX8-PPARγ overexpression in thyroid cancer cell lines and thyroid cancer tissues promoted the proliferation and antiapoptotic ability of thyroid cancer cells and promoted the tumorigenic ability in nude mice in vivo. We successfully prepared a PAX8-PPARγ-targeted ultrasound nanocontrast agent, which has regular morphology, uniform size, and high stability, and its liquid-gas phase change can be promoted at lower temperature. Therefore, this contrast agent can achieve US-targeted imaging and temperature phase transition function, and may have enhanced ultrasound imaging potential.


Assuntos
Meios de Contraste , Neoplasias da Glândula Tireoide , Animais , Meios de Contraste/farmacologia , Detecção Precoce de Câncer , Camundongos , Camundongos Nus , Fator de Transcrição PAX8/genética , PPAR gama , Fatores de Transcrição Box Pareados , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Ultrassonografia
4.
J Healthc Eng ; 2022: 2289432, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35035813

RESUMO

The number of patients with lung cancer is difficultly diagnosed in the early stage. The purpose of the study was to investigate the effects of CT- and ultrasound-guided percutaneous transthoracic needle biopsy combined with serum CA125 and CEA on the diagnosis of lung cancer. 120 patients with suspected lung cancer admitted to our hospital from January 2019 to January 2020 were selected and divided into an ultrasound group (n = 60) and CT group (n = 60), according to different percutaneous transthoracic needle biopsy modalities. All patients received serum tumor markers detection, so as to compare the CT- and ultrasound-guided percutaneous transthoracic needle biopsy results and pathology results, levels of serum tumor markers among all patients and the patients with different lung cancer types, and diagnostic efficacy of tumor markers, as well as complication rate (CR) in patients. The sensitivity and specificity of ultrasound-guided percutaneous transthoracic needle biopsy were 0.880 and 0.800, respectively, while those of CT-guided percutaneous transthoracic needle biopsy were 0.909 and 0.625, respectively; the CA125 and CEA levels in the lung cancer group were higher than those in the benign group (P < 0.001); the CA125 and CEA levels of the patients with adenocarcinoma were higher than those with squamous carcinoma, and the CEA levels of the patients with small-cell carcinoma were lower than those with adenocarcinoma (P < 0.05); the sensitivity, specificity, and Youden indexes of CA125 were 0.638, 0.833, and 0.471, respectively, while those of CEA were 0.766, 0.778, and 0.544, respectively; there were no significant differences in CR between the two groups (P > 0.05). CT- and ultrasound-guided percutaneous transthoracic needle biopsy is a safe and feasible diagnostic modality for lung cancer, and its combination with serum CA125 and CEA can significantly improve the accuracy of the detection results, which is worthy of promotion and application in clinical practice.


Assuntos
Adenocarcinoma , Neoplasias Pulmonares , Adenocarcinoma/diagnóstico , Adenocarcinoma/etiologia , Biomarcadores Tumorais , Biópsia por Agulha/efeitos adversos , Biópsia por Agulha/métodos , Antígeno Carcinoembrionário , Humanos , Neoplasias Pulmonares/diagnóstico , Tomografia Computadorizada por Raios X/métodos , Ultrassonografia de Intervenção
5.
J Am Chem Soc ; 143(34): 13478-13482, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34339184

RESUMO

Carrier generation and migration are both pivotal to photoelectric (PE) response. Formation of a Schottky contact is conducive to promote carrier migration but cannot fundamentally magnify carrier generation, limiting the eventual PE performance. In this work, an Au@Ag/AgI Schottky contact is established by in situ growth of AgI nanotriangles on the surface of Au@Ag nanoparticles (NPs), and PE enhancement of the Schottky contact is realized by regulating localized surface plasmon resonance (LSPR) properties. In comparison with Ag/AgI Schottky contact, assembly of Au NPs in the center of Ag NPs adjusts the dominated LSPR property from hot-electron transfer (HET) to plasmon-induced resonance energy transfer (PIRET). With the concurrent manipulation of HET and PIRET, additional energy can be employed for carrier generation, while photogenerated electrons offset by hot electrons are reduced, which jointly enlarges PE responses of the Au@Ag/AgI Schottky contact up to 4 times. Benefitted from the etching of thiols to Ag-based materials, the Au@Ag/AgI Schottky contact is further applied to the construction of a photoelectrochemical cysteine sensor. This work proposes a general strategy to enhance PE responses of Schottky contacts, which may advance the design of LSPR-related PE systems.

6.
Bioconjug Chem ; 32(6): 1094-1104, 2021 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-34013721

RESUMO

Antibody-drug conjugates (ADCs) are complex pharmaceutical molecules that combine monoclonal antibodies with biologically active drugs through chemical linkers. ADCs are designed to specifically kill disease cells by utilizing the target specificity of antibodies and the cytotoxicity of chemical drugs. However, the traditional ADCs were only applied to a few disease targets because of some limitations such as the huge molecular weight, the uncontrollable coupling reactions, and a single mechanism of action. Here we report a simple, one-pot, successive reaction method to produce dual payload conjugates with the site-specifically engineered cysteine and p-acetyl-phenylalanine using Herceptin (trastuzumab), an anti-HER2 antibody drug widely used for breast cancer treatment, as a tool molecule. This strategy enables antibodies to conjugate with two mechanistically distinct cytotoxic drugs through different functional groups sequentially, therefore, rendering the newly designed ADCs with functional diversity and the potential to overcome drug resistance and enhance the therapeutic efficacy.


Assuntos
Cisteína/química , Imunoconjugados/química , Cinética , Trastuzumab/química
7.
ACS Appl Mater Interfaces ; 12(24): 26905-26913, 2020 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-32427457

RESUMO

Quantitative analysis of receptor protein expression is essential to give new insights into tumor-related research. Benefitting from their high sensitivity and low background, photoelectrochemical (PEC) platforms are considered as powerful tools for evaluating the expression of receptor proteins. Herein, to reduce the cytotoxicity and facilitate the subsequent assembly, l-cysteine-modified Ag-ZnIn2S4 quantum dots (l-Cys AZIS QDs) are prepared and PEC responses under the irradiation of long wavelength light are obtained. To further improve the PEC behavior, iron phthalocyanine (FePc) is employed to form a Z-scheme structure with l-Cys AZIS QDs. The Z-scheme structure based on l-Cys AZIS QDs/FePc hybrid materials exhibits high photo-to-electric conversion efficiency and can be excited with near-infrared range light. Because hyaluronic acid linked to photoactive materials can recognize CD44 expressed on the membrane of cancer cells, cancer cells are immobilized onto l-Cys AZIS QDs/FePc hybrid materials, inducing a decrease of the photocurrent intensity. Consequently, a PEC cytosensor is constructed to quantify cancer cells expressing CD44. The PEC analytical platform is able to determine A549 cells in the range of 2 × 102 to 4.5 × 106 cells/mL, and a detection limit of 15 cells/mL is realized in the case of S/N = 3. In addition, the expression of CD44 in A549 and other five cancer cells is measured with this PEC method. Depending on our data, the expression of CD44 in different cancer cells is distinct, indicating great potential of this method in receptor protein-related studies.


Assuntos
Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Fotoquímica/métodos , Células A549 , Humanos , Receptores de Hialuronatos/metabolismo , Pontos Quânticos
8.
Chem Sci ; 11(14): 3745-3751, 2020 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-34094063

RESUMO

Quantification of circulating tumor DNA (ctDNA) is of great importance in liquid biopsy but difficult due to its low amount in bodily fluids. To meet this high demand, a novel method for ctDNA detection is established by quantifying cyclic DNA polymerization using lanthanide coordination polymers (Ln-CPs). Relying on the coordination between the pyrophosphate ion (PPi) and trivalent cerium ion (Ce3+), organic ligand-free PPi-Ce coordination polymer networks (PPi-Ce CPNs) with enhanced fluorescence are prepared for the first time. By surveying the optical properties of PPi-Ce CPNs, it is found that PPi regulates electric-dipole transition of Ce3+ to the lowest excited state, thus facilitating the emission of fluorescence. Therefore, fluorescence enhancement of PPi-Ce CPNs originates from the ligand field effect rather than the normal antenna effect. Moreover, a new strategy to quantify DNA polymerization is developed based on PPi-Ce CPNs. By introducing multifold cyclic DNA polymerization, a small amount of ctDNA triggers the exponential generation of PPi to form plenty of PPi-Ce CPNs. Accordingly, a biosensor is constructed for sensitive ctDNA detection by measuring the intense fluorescence of PPi-Ce CPNs. The biosensor is capable of sensing ctDNA at the sub-femtomolar level, which is far better than the analytical performances of commercial dyes. Besides, the analytical method is able to detect single nucleotide polymorphism and determine ctDNA in real samples. Considering that DNA polymerization is widely used in bio-recognition, bio-assembly and biomineralization, the work provides a versatile quantitative strategy of making relevant processes precise and controllable.

9.
Chem Sci ; 10(21): 5616-5623, 2019 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-31293746

RESUMO

Currently, reported affinity pairings still lack in diversity, and thus terminal protection relying on steric hindrance is restricted in designing nucleic acid-based analytical systems. In this work, resistance to exonuclease is testified by group modification or backbone replacement, and the 3'-phosphate group (P) reveals the strongest exonuclease I-resistant capability. Due to the substrate specificity of enzymatic catalysis, this 3'-P protection works in a "direct mode". By introducing DNA templated copper nanoparticles, an alkaline phosphatase assay is performed to confirm the 3'-P protection. To display the application of this novel terminal protection, a multifunctional DNA is designed to quantify the model circulating microRNA (hsa-miR-21-5p) in serums from different cancer patients. According to our data, hsa-miR-21-5p-correlated cancers can be evidently distinguished from non-correlated cancers. Meanwhile, the effect of chemotherapy and radiotherapy on breast cancer is evaluated from the perspective of hsa-miR-21-5p residue in serums. Since greatly reducing the limitations of DNA design, this P-induced terminal protection can be facilely integrated with other DNA manipulations, thereby constructing more advanced biosensors with improved analytical performances for clinical applications.

10.
Anal Chem ; 91(14): 8987-8993, 2019 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-31265249

RESUMO

Although attractive for their low toxicity, CuInS2/ZnS core/shell quantum dots (CIS/ZnS QDs) still suffer from poor luminescence efficiency and poor water solubility. Herein, two amino acids (AAs), i.e., cysteine (Cys) and threonine (Thr), are used to tune the properties of CIS/ZnS QDs by capping them in both core and shell. It is found that Thr can regulate the density of Cys on the surface of QDs, thus causing a synergistic effect on the enhancement of photoluminescence (PL) intensity. Capping in the shell mainly leads to the enhancement of PL intensity, and capping in the core results in a red-shift of PL wavelength. Accordingly, a new kind of near-infrared region CIS/ZnS QDs with improved optical properties has been prepared. In addition, the Cys- and Thr-capped CIS/ZnS QDs possess outstanding water solubility and biocompatibility. In this work, the QDs are further employed in Cd2+ determination and multicolor imaging, indicating their potential applications. Relying on the enhancement of PL intensity via cation exchange, the Cys- and Thr-capped CIS/ZnS QDs can sense Cd2+ sensitively. Notably, because ZnS shells of the QDs will not be affected by Zn2+, the analytical method can discriminate Cd2+ from Zn2+ depending on the inherent characteristics of QDs. Moreover, intercellular Cd2+ can also be evaluated by the bright PL from the QDs, and the QDs can achieve multicolor imaging. Overall, this work demonstrates that various properties of QDs may be tuned by capping with AAs, and AA-capped QDs are of great value in advanced biosensing and bioimaging.


Assuntos
Cádmio/análise , Cisteína/química , Corantes Fluorescentes/química , Pontos Quânticos/química , Treonina/química , Cobre/química , Cobre/toxicidade , Cisteína/toxicidade , Corantes Fluorescentes/toxicidade , Índio/química , Índio/toxicidade , Limite de Detecção , Microscopia Confocal/métodos , Microscopia de Fluorescência/métodos , Pontos Quânticos/toxicidade , Solubilidade , Sulfetos/química , Sulfetos/toxicidade , Treonina/toxicidade , Água/química , Compostos de Zinco/química , Compostos de Zinco/toxicidade
11.
Anal Chem ; 91(1): 830-835, 2019 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-30289248

RESUMO

The excitonic response between nanomaterials is distance-dependent, and thus, interparticle distance is a key factor in fabricating diverse photoelectrochemical (PEC) systems. Current studies focus on DNA-mediated regulation of interparticle distance. However, limited by high demands of base-pairing and flexibility of DNA, it is hard for DNA to achieve precise regulation, especially in a short distance. To pursue better PEC performances in bioanalyses, alternative biological materials should be explored to replace DNA as new "distance controllers". In this work, a peptide with three functional sequences is designed to control interparticle distance between positive-charged Au nanoparticles ((+) AuNPs) and negative-charged CdTe quantum dots ((-) CdTe QDs). Relying on the function of binding sequence, (+) AuNPs and (-) CdTe QDs may be separated to a certain distance by the multifunctional peptide. In this case, the excitonic response is relatively weak, and an evident PEC response can be observed. Because it contains the substrate sequence of caspase-3, the peptide is cleaved in the presence of caspase-3. As a result, without the support of intact peptide, electrostatic attraction plays a dominant role, leading to the aggregation of oppositely charged AuNPs and CdTe QDs, which strengthens the excitonic response and attenuates the PEC response. On the basis of these principles, a novel PEC approach was fabricated to sensitively quantify caspase-3. Meanwhile, caspase-3 in staurosporine-treated A549 cells are also determined by the approach, and the obtained results agree well with the fluorescent intensity of confocal images, manifesting that the proposed PEC method can monitor apoptosis in a label-free strategy. Overall, the study reveals the capability of peptides in controlling interparticle distance of nanomaterials, which may accelerate the development of peptide-based PEC analytical methods.


Assuntos
Apoptose/efeitos dos fármacos , Caspase 3/análise , Técnicas Eletroquímicas/métodos , Nanopartículas Metálicas/química , Fotoquímica/métodos , Pontos Quânticos/química , Células A549 , Sequência de Aminoácidos , Compostos de Cádmio/química , Ouro/química , Humanos , Limite de Detecção , Peptídeos/química , Estaurosporina/farmacologia , Telúrio/química
12.
Anal Chim Acta ; 1008: 90-95, 2018 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-29420949

RESUMO

Since abnormal metabolism of histidine (His) is defined as an indicator of several diseases, detection of His in biological fluids becomes increasingly urgent to us. However, due to similar structures and properties of different amino acids, selective quantification of His is difficulty, and typically needs the participation of special reagents. In this work, we report for the first time that nickel ions (Ni2+) can induce the allostery of G-quadruplex, and is thus able to manipulate the activity of G-quadruplex DNAzyme. Experimental results indicate the interaction between Ni2+ and guanine is critical to the allostery. In comparison with Ni2+-guanine interaction, Ni2+-His interaction exhibits higher affinity. Therefore, a colorimetric His biosensor is fabricated, and His can be facilely discriminated by naked eyes. Relying on the high activity of DNAzyme, His in a range of 50 nM-400 µM is determined with this method, and low detection limit (36 nM) is obtained. More importantly, His can be directly distinguished in the absence of other toxic reagents. In addition, the amount of His in serum is also measured, suggesting the applicability of this biosensor in real sample detection. Overall, this work provides an alternative way to design G-quadruplex DNAzyme-based analytical approaches.


Assuntos
DNA Catalítico/metabolismo , Quadruplex G , Histidina/análise , Níquel/metabolismo , Regulação Alostérica , Técnicas Biossensoriais , Colorimetria , DNA Catalítico/química , Histidina/metabolismo , Níquel/química
13.
Biosens Bioelectron ; 94: 56-62, 2017 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-28257975

RESUMO

MicroRNAs (miRNAs) play important roles in gene regulation and cancer development. Nowadays, it is still a challenge to detect low-abundance miRNAs. Here, we present a magnetic fluorescent miRNA sensing system for the rapid and sensitive detection of miRNAs from cell lysates and serum samples. In this system, albumin nanoparticles (Alb NPs) were prepared from inherent biocompatible bovine serum albumin (BSA). A large number of fluorescent dyes were loaded into Alb NPs to make Alb NPs serve as signal molecular nanocarriers for signal amplification. Benefited from the reactive functional groups-carboxyl groups of Alb NPs, p19 protein, a viral protein that can bind and sequester short RNA duplex effectively and selectively, was modified successfully to the surface of the fluorescent dyes-loaded Alb NPs, thus enabling the probe:target miRNA duplex recognition and binding. Followed by the introduction of gold nanoparticles coated magnetic microbeads (Au NPs-MBs), which were prepared through a novel and simple method, the system combined the merits of the rapid and efficient collection given by MBs with the good affinities to attach probe molecules endowed by the coated gold layer. A broad linear detection range of 10fM-10nM and a low detection limit of 9fM were obtained within 100min by detecting a model target miRNA-21. The feasibility of this method for rapid and sensitive quantification might advance the use of miRNAs as biomarkers in clinical praxis significantly.


Assuntos
Técnicas Biossensoriais/métodos , Nanopartículas Metálicas/química , MicroRNAs/isolamento & purificação , Soroalbumina Bovina/química , Animais , Bovinos , Corantes Fluorescentes/química , Ouro/química , Humanos , MicroRNAs/genética
14.
Oncol Rep ; 36(2): 685-95, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27279438

RESUMO

Meningiomas are common types of adult nerve system tumors. Although most cases are considered benign, due to its high rate of recurrence and easy malignant progression to anaplastic meningioma they present a puzzle for the current treatment. The HER-2 oncogene has important value for meningioma cells development and progression. So far, little is known about the effect on the exact underlying signal pathway and molecular mechanisms of HER-2-positive meningioma cells. The goal of the present study was to determine the effects of HER-2 gene and possible involvement of MAPK signal pathway in human malignant meningioma. We applied q-PCR analysis, immunofluorescence (IF) staining, western blot analysis, animal model, MAPK inhibition, MTT assay and cell invasion analysis for the investigation. The results demonstrated that the downregulation of the expression of HER-2 significantly inhibited cell motility and proliferation of human meningioma cells in vivo. Accordingly, in the HER-2-overexpression meningioma cells with the inhibition of ERK1/2, ERK5, JNK, in the cells with the ERK1/2, ERK5 inhibition, protein expression was markedly suppressed as well as the cell proliferation resistance. No difference was observed in the HER-2-overexpression meningioma cells with the inhibition of JNK. These findings suggest that HER-2 gene can affect the proliferation ability of human meningioma cells in vivo and MAPK signal pathway may contribute to the carcinogenesis and development of human meningiomas combinating with HER-2.


Assuntos
Neoplasias Meníngeas/metabolismo , Meningioma/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Receptor ErbB-2/metabolismo , Transdução de Sinais/fisiologia , Animais , Carcinogênese/metabolismo , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Regulação para Baixo/fisiologia , Feminino , Humanos , Sistema de Sinalização das MAP Quinases/fisiologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteína Quinase 7 Ativada por Mitógeno/metabolismo
15.
Analyst ; 141(13): 4006-9, 2016 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-27221644

RESUMO

Herein, a label-free fluorescent adenosine triphosphate (ATP) aptasensor is fabricated with a DNA hairpin and an overhanging aptamer. In the presence of ATP, the overhanging sequences of the aptamer may form preferred substrates of exo III, and thus trigger the enzyme-assisted amplification, which results in the release of G-rich sequences. Free G-rich sequences subsequently generate an enhanced flourescent signal by binding with thioflavin T. However, if ATP is absent, the overhanging sequence can induce steric hindrance and protect the DNA hairpin against the digestion of exo III, significantly reducing the noise of this biosensor. Accordingly, the signal-to-noise ratio of the sensing system is greatly improved, which ensures the desirable analytical performance of the proposed aptasensor both in pure samples and real samples.


Assuntos
Trifosfato de Adenosina/química , Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais , Benzotiazóis , Exodesoxirribonucleases/química , Humanos , Tiazóis/química
16.
Chem Commun (Camb) ; 51(75): 14259-62, 2015 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-26264188

RESUMO

A universal and label-free photoelectrochemical cytosensing strategy was designed based on resonance energy transfer (RET) between carbon dots and cysteamine capped gold nanoparticles. RET promoted photo-to-current conversion efficiency and enhanced detection sensitivity. This proposed photoelectrochemical cytosensing platform exhibited a good performance for the assay of tumor cells with overexpressed receptors on cells.


Assuntos
Carbono/química , Cisteamina/química , Técnicas Eletroquímicas , Transferência Ressonante de Energia de Fluorescência , Ouro/química , Nanopartículas Metálicas/química , Células HeLa , Humanos , Processos Fotoquímicos
17.
Bioorg Med Chem Lett ; 17(11): 3038-43, 2007 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-17418572

RESUMO

Some DP1 receptor antagonists from an indole-containing series were shown to cause in vitro covalent binding to protein in rat and human liver microsomes. Glutathione trapping experiments along with in vitro labeling assays confirmed that the presence of a strong electron withdrawing group was necessary to abrogate in vitro covalent binding, leading to the discovery of MK-0524. Hepatocyte incubations and in vivo studies showed that acyl-glucuronide formation did not translate into covalent binding.


Assuntos
Glutationa/metabolismo , Indóis/agonistas , Indóis/metabolismo , Microssomos Hepáticos/metabolismo , Receptores Imunológicos/antagonistas & inibidores , Receptores de Prostaglandina/antagonistas & inibidores , Animais , Elétrons , Glucuronídeos/biossíntese , Hepatócitos/metabolismo , Hepatócitos/ultraestrutura , Humanos , Indóis/química , Proteínas/metabolismo , Ratos
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