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1.
Nat Commun ; 15(1): 3483, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38664416

RESUMO

Chemical discovery efforts commonly target individual protein domains. Many proteins, including the EP300/CBP histone acetyltransferases (HATs), contain several targetable domains. EP300/CBP are critical gene-regulatory targets in cancer, with existing high potency inhibitors of either the catalytic HAT domain or protein-binding bromodomain (BRD). A domain-specific inhibitory approach to multidomain-containing proteins may identify exceptional-responding tumor types, thereby expanding a therapeutic index. Here, we discover that targeting EP300/CBP using the domain-specific inhibitors, A485 (HAT) or CCS1477 (BRD) have different effects in select tumor types. Group 3 medulloblastoma (G3MB) cells are especially sensitive to BRD, compared with HAT inhibition. Structurally, these effects are mediated by the difluorophenyl group in the catalytic core of CCS1477. Mechanistically, bromodomain inhibition causes rapid disruption of genetic dependency networks that are required for G3MB growth. These studies provide a domain-specific structural foundation for drug discovery efforts targeting EP300/CBP and identify a selective role for the EP300/CBP bromodomain in maintaining genetic dependency networks in G3MB.


Assuntos
Proteína p300 Associada a E1A , Redes Reguladoras de Genes , Meduloblastoma , Humanos , Meduloblastoma/genética , Meduloblastoma/tratamento farmacológico , Meduloblastoma/metabolismo , Meduloblastoma/patologia , Proteína p300 Associada a E1A/metabolismo , Proteína p300 Associada a E1A/genética , Proteína p300 Associada a E1A/antagonistas & inibidores , Linhagem Celular Tumoral , Redes Reguladoras de Genes/efeitos dos fármacos , Animais , Domínios Proteicos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Camundongos , Neoplasias Cerebelares/genética , Neoplasias Cerebelares/tratamento farmacológico , Neoplasias Cerebelares/metabolismo , Neoplasias Cerebelares/patologia , Antineoplásicos/farmacologia
2.
Nat Commun ; 15(1): 1367, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38355622

RESUMO

Anti-CD38 monoclonal antibodies like Daratumumab (Dara) are effective in multiple myeloma (MM); however, drug resistance ultimately occurs and the mechanisms behind this are poorly understood. Here, we identify, via two in vitro genome-wide CRISPR screens probing Daratumumab resistance, KDM6A as an important regulator of sensitivity to Daratumumab-mediated antibody-dependent cellular cytotoxicity (ADCC). Loss of KDM6A leads to increased levels of H3K27me3 on the promoter of CD38, resulting in a marked downregulation in CD38 expression, which may cause resistance to Daratumumab-mediated ADCC. Re-introducing CD38 does not reverse Daratumumab-mediated ADCC fully, which suggests that additional KDM6A targets, including CD48 which is also downregulated upon KDM6A loss, contribute to Daratumumab-mediated ADCC. Inhibition of H3K27me3 with an EZH2 inhibitor resulted in CD38 and CD48 upregulation and restored sensitivity to Daratumumab. These findings suggest KDM6A loss as a mechanism of Daratumumab resistance and lay down the proof of principle for the therapeutic application of EZH2 inhibitors, one of which is already FDA-approved, in improving MM responsiveness to Daratumumab.


Assuntos
Mieloma Múltiplo , Humanos , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/genética , Epigênese Genética , Histonas/metabolismo , ADP-Ribosil Ciclase 1 , Células Matadoras Naturais
3.
Cancer Discov ; 12(12): 2880-2905, 2022 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-36305736

RESUMO

Diffuse midline gliomas are uniformly fatal pediatric central nervous system cancers that are refractory to standard-of-care therapeutic modalities. The primary genetic drivers are a set of recurrent amino acid substitutions in genes encoding histone H3 (H3K27M), which are currently undruggable. These H3K27M oncohistones perturb normal chromatin architecture, resulting in an aberrant epigenetic landscape. To interrogate for epigenetic dependencies, we performed a CRISPR screen and show that patient-derived H3K27M-glioma neurospheres are dependent on core components of the mammalian BAF (SWI/SNF) chromatin remodeling complex. The BAF complex maintains glioma stem cells in a cycling, oligodendrocyte precursor cell-like state, in which genetic perturbation of the BAF catalytic subunit SMARCA4 (BRG1), as well as pharmacologic suppression, opposes proliferation, promotes progression of differentiation along the astrocytic lineage, and improves overall survival of patient-derived xenograft models. In summary, we demonstrate that therapeutic inhibition of the BAF complex has translational potential for children with H3K27M gliomas. SIGNIFICANCE: Epigenetic dysregulation is at the core of H3K27M-glioma tumorigenesis. Here, we identify the BRG1-BAF complex as a critical regulator of enhancer and transcription factor landscapes, which maintain H3K27M glioma in their progenitor state, precluding glial differentiation, and establish pharmacologic targeting of the BAF complex as a novel treatment strategy for pediatric H3K27M glioma. See related commentary by Beytagh and Weiss, p. 2730. See related article by Mo et al., p. 2906.


Assuntos
Epigenoma , Glioma , Animais , Humanos , Mutação , Glioma/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Células-Tronco Neoplásicas/metabolismo , Mamíferos/genética , Mamíferos/metabolismo , DNA Helicases/genética , Proteínas Nucleares/genética
4.
Cancer Discov ; 12(3): 730-751, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-34772733

RESUMO

Gene expression is regulated by promoters and enhancers marked by histone H3 lysine 27 acetylation (H3K27ac), which is established by the paralogous histone acetyltransferases (HAT) EP300 and CBP. These enzymes display overlapping regulatory roles in untransformed cells, but less characterized roles in cancer cells. We demonstrate that the majority of high-risk pediatric neuroblastoma (NB) depends on EP300, whereas CBP has a limited role. EP300 controls enhancer acetylation by interacting with TFAP2ß, a transcription factor member of the lineage-defining transcriptional core regulatory circuitry (CRC) in NB. To disrupt EP300, we developed a proteolysis-targeting chimera (PROTAC) compound termed "JQAD1" that selectively targets EP300 for degradation. JQAD1 treatment causes loss of H3K27ac at CRC enhancers and rapid NB apoptosis, with limited toxicity to untransformed cells where CBP may compensate. Furthermore, JQAD1 activity is critically determined by cereblon (CRBN) expression across NB cells. SIGNIFICANCE: EP300, but not CBP, controls oncogenic CRC-driven transcription in high-risk NB by binding TFAP2ß. We developed JQAD1, a CRBN-dependent PROTAC degrader with preferential activity against EP300 and demonstrated its activity in NB. JQAD1 has limited toxicity to untransformed cells and is effective in vivo in a CRBN-dependent manner. This article is highlighted in the In This Issue feature, p. 587.


Assuntos
Neuroblastoma , Sequências Reguladoras de Ácido Nucleico , Acetilação , Criança , Proteína p300 Associada a E1A/genética , Humanos , Proteína Proto-Oncogênica N-Myc/genética , Neuroblastoma/tratamento farmacológico , Neuroblastoma/genética , Oncogenes
5.
Blood Cancer Discov ; 2(4): 370-387, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34258103

RESUMO

Lysine demethylase 5A (KDM5A) is a negative regulator of histone H3K4 trimethylation, a histone mark associated with activate gene transcription. We identify that KDM5A interacts with the P-TEFb complex and cooperates with MYC to control MYC targeted genes in multiple myeloma (MM) cells. We develop a cell-permeable and selective KDM5 inhibitor, JQKD82, that increases histone H3K4me3 but paradoxically inhibits downstream MYC-driven transcriptional output in vitro and in vivo. Using genetic ablation together with our inhibitor, we establish that KDM5A supports MYC target gene transcription independent of MYC itself, by supporting TFIIH (CDK7)- and P-TEFb (CDK9)-mediated phosphorylation of RNAPII. These data identify KDM5A as a unique vulnerability in MM functioning through regulation of MYC-target gene transcription, and establish JQKD82 as a tool compound to block KDM5A function as a potential therapeutic strategy for MM.


Assuntos
Lisina , Mieloma Múltiplo , Quinase 9 Dependente de Ciclina/metabolismo , Quinases Ciclina-Dependentes/metabolismo , Genes cdc , Humanos , Metilação , Mieloma Múltiplo/genética , Proteínas Proto-Oncogênicas c-myc/genética , RNA Polimerase II , Proteína 2 de Ligação ao Retinoblastoma , Quinase Ativadora de Quinase Dependente de Ciclina
6.
J Med Chem ; 64(9): 5787-5801, 2021 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-33872011

RESUMO

The use of epigenetic bromodomain inhibitors as anticancer therapeutics has transitioned from targeting bromodomain extraterminal domain (BET) proteins into targeting non-BET bromodomains. The two most relevant non-BET bromodomain oncology targets are cyclic AMP response element-binding protein (CBP) and E1A binding protein P300 (EP300). To explore the growing CBP/EP300 interest, we developed a highly efficient two-step synthetic route for dimethylisoxazole-attached imidazo[1,2-a]pyridine scaffold-containing inhibitors. Our efficient two-step reactions enabled high-throughput synthesis of compounds designed by molecular modeling, which together with structure-activity relationship (SAR) studies facilitated an overarching understanding of selective targeting of CBP/EP300 over non-BET bromodomains. This led to the identification of a new potent and selective CBP/EP300 bromodomain inhibitor, UMB298 (compound 23, CBP IC50 72 nM and bromodomain 4, BRD4 IC50 5193 nM). The SAR we established is in good agreement with literature-reported CBP inhibitors, such as CBP30, and demonstrates the advantage of utilizing our two-step approach for inhibitor development of other bromodomains.


Assuntos
Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/antagonistas & inibidores , Proteína p300 Associada a E1A/antagonistas & inibidores , Isoxazóis/química , Piridinas/química , Sítios de Ligação , Proteínas de Ciclo Celular/antagonistas & inibidores , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cristalografia por Raios X , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Proteína p300 Associada a E1A/metabolismo , Humanos , Simulação de Acoplamento Molecular , Piridinas/metabolismo , Piridinas/farmacologia , Relação Estrutura-Atividade , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/metabolismo
7.
Mol Cell ; 78(6): 1086-1095, 2020 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-32407673

RESUMO

Transcription is epigenetically regulated by the orchestrated function of chromatin-binding proteins that tightly control the expression of master transcription factors, effectors, and supportive housekeeping genes required for establishing and propagating the normal and malignant cell state. Rapid advances in chemical biology and functional genomics have facilitated exploration of targeting epigenetic proteins, yielding effective strategies to target transcription while reducing toxicities to untransformed cells. Here, we review recent developments in conventional active site and allosteric inhibitors, peptidomimetics, and novel proteolysis-targeted chimera (PROTAC) technology that have deepened our understanding of transcriptional processes and led to promising preclinical compounds for therapeutic translation, particularly in cancer.


Assuntos
Epigênese Genética/efeitos dos fármacos , Epigênese Genética/genética , Neoplasias/genética , Animais , Antineoplásicos/farmacologia , Cromatina/genética , Cromatina/metabolismo , Epigênese Genética/fisiologia , Epigenômica/métodos , Humanos , Neoplasias/terapia , Proteólise/efeitos dos fármacos , Fatores de Transcrição/metabolismo
8.
Medicine (Baltimore) ; 99(9): e18644, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32118704

RESUMO

BACKGROUND: Ki-67 is a typical immunohistochemical marker for cell proliferation. Higher expression of Ki-67 is correlated with poor clinical outcomes in several cancers. However, the prognostic value of Ki-67 on the prognosis of meningiomas is still controversial. The purpose of this meta-analysis was to evaluate the prognostic value of Ki-67 in meningiomas. METHODS AND MATERIALS: We searched Medline and EMBASE from inception to December 31, 2018, to identify relevant articles. Using a fixed or random effects model, pooled hazard ratios (HRs) for overall survival (OS) and disease/progression/recurrence-free survival (D/P/RFS) were estimated. RESULTS: A total of 43 studies, comprising 5012 patients, were included in this analysis. Higher Ki-67 expression levels were significantly associated with worse OS (HR = 1.565; 95% CI: 1.217-2.013) and D/P/RFS (HR = 2.644; 95% CI: 2.264-3.087) in meningiomas. Subgroup analysis revealed that all the included factors (ethnicity, tumor grade, HR sources, definition of cutoffs, cutoff values) for heterogeneity investigation can affect the pooled results. Among them, the definitions of cutoffs and cutoff values factor are the two main contributors toward heterogeneity. Multivariable meta-regression analysis also showed that methodologies used for cutoff value definition contributed to the high inner-study heterogeneity. CONCLUSIONS: Higher Ki-67 expression levels negatively influenced survival in meningiomas. A higher cutoff value (>4%) is more appropriate for prognosis prediction. It is highly recommended that Ki-67 expression profile could be assessed in meningiomas treatment for predicting survival. And patients with elevated expression of Ki-67 need to have close follow-ups.


Assuntos
Antígeno Ki-67/metabolismo , Meningioma/metabolismo , Meningioma/mortalidade , Biomarcadores Tumorais/metabolismo , Humanos , Meningioma/diagnóstico , Prognóstico
9.
J Cancer ; 10(18): 4305-4317, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31413750

RESUMO

Red blood cell distribution width (RDW) has been recently demonstrated to be a predictor of inflammation. High pretreatment RDW level is associated with poor survival outcomes in various malignancies, although the results are controversial. We aimed to investigate the prognostic role of RDW. A systematic literature search was performed in MEDLINE and EMBASE till April 2018. Pooled hazard ratios (HRs) were estimated for overall survival (OS) and combined disease-free survival, progression-free survival, and recurrence-free survival (DFS/PFS/RFS). 49 studies with 19,790 individuals were included in the final analysis. High RDW level adversely affected both OS and DFS/PFS/RFS. For solid cancers, colorectal cancer (CRC) had the strongest relationship with poor OS, followed by hepatic cancer (HCC). Negative OS outcomes were also observed in hematological malignancies. Furthermore, patients at either early or advanced stage had inverse relationship between high pretreatment RDW and poor OS. Studies with cut-off values between 13% and 14% had worse HRs for OS and DFS/PFS/RFS than others. Furthermore, region under the curve (ROC) analysis was used widely to define cut-off values and had relatively closer relationship with poorer HRs. In conclusion, our results suggested that elevated pretreatment RDW level could be a negative predictor for cancer prognosis.

10.
Oncoimmunology ; 7(10): e1494113, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30288362

RESUMO

Myeloid-derived suppressor cells (MDSCs) have been shown to contribute to tumor progression, mainly through immune suppression. Inverse correlations have been observed between MDSC levels and patient survival for various malignancies. The purpose of this meta-analysis was to evaluate the prognostic value of pretreatment circulating MDSCs. We searched MEDLINE and EMBASE from their inceptions to September 2017 to identify relevant articles. Using a fixed or random effects model, pooled hazard ratios (HRs) were estimated for overall survival (OS) and combined disease-free survival, progression-free survival, and recurrence-free survival (DFS/PFS/RFS). A total of 40 studies comprising 2721 were included. For solid tumors, high levels of pretreatment circulating MDSCs were significantly associated with worse OS (HR = 1.796, 95% CI = 1.587-2.032) and DFS/PFS/RFS (HR = 2.459, 95% CI = 2.018-2.997). Breast cancer showed the largest association between high MDSC levels and worse OS (pooled HR = 3.053). Elevated MDSCs were also associated with worse OS for mixed-stage tumors (pooled HR = 1.659) and advanced-stage tumors (pooled HR = 2.337). Furthermore, both monocytic-MDSCs (M-MDSCs) and granulocytic or polymorphonuclear (PMN-MDSCs) showed negative associations with survival outcomes. Overall, high levels of pretreatment circulating MDSCs negatively influenced survival in most cancers. Pretreatment circulating MDSCs should be taken into account to further improve prognostic evaluation and develop novel therapeutic strategies.

11.
J Neurooncol ; 139(1): 89-95, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29680903

RESUMO

BACKGROUND: Pituitary adenomas (PAs) are the second most common brain tumors, and mostly are benign tumors. However, there exists subtypes of PAs refractory to common treatments, and need novel therapy. Programmed death 1 (PD-1) blockade has shown durable objective response in a variety of malignancies, and the key predictive markers for this immunotherapy were PD-L1 and CD8+ tumor-infiltrating lymphocyte (TILs) expression. To evaluate the potential immunotherapy for PAs, we investigated the expression of these two immune markers in PAs. METHODS: Immunohistochemistry (IHC) was performed to detect the expression of PD-L1 and CD8+ TILs in PAs. The ratio of positive expression of PD-L1 and CD8+ TILs was compared with chi-squared tests among different subtypes of PAs. The association between their expression profile and clinical parameters was analyzed using a chi-squared test, or Fisher's exact probability test when appropriate. RESULTS: One hundred and ninety one patients with PAs were retrospectively involved in this study, consisting of 106 non-functioning PAs (NF-PAs, 55.5%), 40 PRL-secreting PAs (PRL-PAs, 20.9%), 31 GH-secreting PAs (GH-PAs, 16.2%), 9 ACTH-secreting PAs (ACTH-PAs, 4.7%) and 5 plurihormonal adenomas (2.6%) respectively. 36.6% of them were PD-L1 positive and 86.9% were CD8+ TILs positive. The positive PD-L1 immunostaining presented more frequently in functioning PAs (58.8%), compared with that (34.3%) in nonfunctioning group (p = 0.000). Moreover, the rates of PD-L1 expression were more associated with increased blood levels of PRL, GH, ACTH and cortisol. Contrastly, positive CD8+ TILs immunostaining was only correlated with elevated blood level of GH. For the analysis of immune markers with pathological results, PD-L1 expression was associated with PRL and GH immunostaining and higher Ki-67 index. But CD8+ TILs was only correlated with PRL immunostaining. CONCLUSION: Our results showed that PD-L1 was frequently expressed in functioning PAs with association of aggressive behaviors in PAs. The immunotherapy could be a promising treatment option of PAs.


Assuntos
Adenoma/imunologia , Antígeno B7-H1/metabolismo , Linfócitos T CD8-Positivos/imunologia , Imunoterapia , Neoplasias Hipofisárias/imunologia , Adenoma/patologia , Adenoma/terapia , Adolescente , Adulto , Idoso , Biomarcadores Tumorais/metabolismo , Linfócitos T CD8-Positivos/patologia , Criança , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Hipofisárias/patologia , Neoplasias Hipofisárias/terapia , Estudos Retrospectivos , Adulto Jovem
12.
Mikrochim Acta ; 185(4): 244, 2018 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-29610993

RESUMO

The authors describe MnO nanoparticles (NPs) with unique excitation-dependent fluorescence across the entire visible spectrum. These NPs are shown to be efficient optical nanoprobe for multicolor cellular imaging. Synthesis of the NPs is accomplished by a thermal decomposition method. The MnO NPs exhibit a high r1 relaxivity of 4.68 mM-1 s-1 and therefore give an enhanced contrast effect in magnetic resonance (MR) studies of brain glioma. The cytotoxicity assay, hemolysis analysis, and hematoxylin and eosin (H&E) staining tests verify that the MnO NPs are biocompatible. In the authors' perception, the simultaneous attributes of multicolor fluorescence and excellent MR functionality make this material a promising dual-modal nanoprobe for use in bio-imaging. Graphical abstract A direct method to synthesize fluorescent MnO NPs is reported. The NPs are biocompatible and have been successfully applied for multicolor cellular imaging and MR detection of brain glioma.


Assuntos
Neoplasias Encefálicas/diagnóstico , Meios de Contraste/química , Glioma/diagnóstico , Compostos de Manganês/química , Nanopartículas/química , Óxidos/química , Animais , Encéfalo/patologia , Linhagem Celular Tumoral , Meios de Contraste/síntese química , Meios de Contraste/toxicidade , Fluorescência , Imageamento por Ressonância Magnética/métodos , Compostos de Manganês/síntese química , Camundongos Endogâmicos ICR , Nanopartículas/toxicidade , Óxidos/síntese química , Óxidos/toxicidade , Ratos
13.
Biochem Biophys Res Commun ; 499(3): 488-492, 2018 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-29580992

RESUMO

The albumin-templated Gd2O3 and MnO2 nanoparticles (NPs) have been developed as a new type of magnetic resonance (MR) T1 contrast agents. However, their potential toxicity and applicability for MR imaging of brain gliomas has not been fully explored so far. In this study, we prepared Gd2O3@BSA and MnO2@BSA nanoparticles (NPs) and investigated their toxicity comprehensively and comparatively by H&E staining, blood biochemical analysis, and adverse outcome pathways testing. It is revealed that both Gd2O3@BSA and MnO2@BSA NPs are biocompatible at a rational dose level. Although the relaxivity of MnO2@BSA NPs is less than that of Gd2O3@BSA NPs, the MnO2@BSA NPs lead to a greater contrast enhancement in the brain glioma due to the controlled release of Mn ions under the acidic tumor microenvironmental conditions. These comparative toxicity and contrast enhancement data are of fundamental importance for the clinical translation of Gd2O3@BSA and MnO2@BSA NPs as MR contrast agents for brain glioma diagnosis.


Assuntos
Neoplasias Encefálicas/patologia , Meios de Contraste/toxicidade , Gadolínio/toxicidade , Glioma/patologia , Imageamento por Ressonância Magnética , Nanopartículas Metálicas/toxicidade , Óxidos/toxicidade , Soroalbumina Bovina/química , Animais , Injeções Intravenosas , Compostos de Manganês , Nanopartículas Metálicas/ultraestrutura , Camundongos
14.
J Oral Pathol Med ; 47(4): 353-358, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29406591

RESUMO

BACKGROUND: A number of studies have assessed the prognostic value of the neutrophil-to-lymphocyte ratio (NLR) in oral squamous cell carcinoma (OSCC), but their results regarding the predictive value of NLR in OSCC are inconsistent. We therefore performed a meta-analysis to clarify the association between NLR and clinical outcome in OSCC. METHODS: We searched the MEDLINE and Web of Science to identify potential studies investigating the association between NLR and survival in OSCC. RESULTS: A total of 10 studies, enrolling 2135 patients with OSCC, were included. A higher NLR was a negative predictor for both disease-specific survival (hazard ratio [HR] = 1.93, 95% CI: 1.47-2.54) and overall survival (HR = 1.56, 95% CI: 1.28-1.90). CONCLUSION: This suggests a higher NLR is predictive of a poorer prognosis in OSCC. Because determination of NLR is non-invasive and cost-effective, it could be widely used for predicting prognosis in OSCC.


Assuntos
Carcinoma de Células Escamosas/sangue , Linfócitos , Neoplasias Bucais/sangue , Neutrófilos , Humanos , Contagem de Leucócitos , Prognóstico , Taxa de Sobrevida
15.
ACS Biomater Sci Eng ; 4(6): 2089-2094, 2018 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-33435031

RESUMO

Brain gliomas are life-threatening diseases with low survival rates. Early detection and accurate intraoperative location of brain gliomas is vital to improving the prognosis. Herein, we synthesized manganese (Mn)-doped carbon dots (CDs) as magnetic resonance (MR)/optical dual-modal imaging nanoprobes by a one-pot green microwave-assisted route. These ultra-small-sized Mn-doped CDs possess distinct excitation-dependent photoluminescent emissions, high r1 relaxivity, and low cytotoxicity. The in vivo MR imaging and ex vivo optical imaging of mouse brain with tiny glioma demonstrate that the Mn-doped CDs could lead to an enhanced MR T1 contrast effect in the tiny brain glioma region, disclosing the great promise of these Mn-doped CDs as MR/optical dual-modal imaging nanoprobes for detection and intraoperative location of tiny brain gliomas.

16.
ACS Appl Mater Interfaces ; 10(1): 1084-1092, 2018 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-29251905

RESUMO

Integration of optical imaging modality with photothermal therapy (PTT) for simultaneously providing oncotherapy and bioimaging enables an optimized therapeutic efficacy and higher treatment accuracy and therefore has emerged as a prospective cancer treatment. However, it remains challenging to develop biocompatible PTT nanoagents capable of imaging, monitoring, and diagnosis. Carbon dots (CDs) possess unique photoluminescent (PL) properties and intrinsic biocompatibility; while Prussian blue nanoparticles (PBNPs) are nontoxic with efficient photothermal conversion capacity for PTT. Herein, a simple, cost-effective, and environmentally benign method was developed to strategically fabricate CD-decorated PBNP (CDs/PBNP) nanocomposites with satellite/core structure. The CDs/PBNPs possess distinct green PL emission and near-infrared photoabsorption with high efficiency and photothermal stability. In vitro and in vivo toxicity tests prove the biocompatibility of the CDs/PBNPs. Moreover, the applicability of CDs/PBNPs as nanotheranostic agents was tested, which suggests that CDs/PBNPs possess promising imaging and effective tumor ablation properties.


Assuntos
Nanocompostos , Carbono , Ferrocianetos , Fototerapia , Estudos Prospectivos
17.
Medicine (Baltimore) ; 96(49): e9056, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29245312

RESUMO

RATIONALE: Pituitary adenomas secreting two or more hormones were referred to the plurihormonal tumors. The management of this type of the tumor was tumor resection and amelioration of the unbalanced hormones. However, it washard to cure the plurihormonal adenomas, as they were usually refractory to the traditional treatment. New therapeutic methods were needed in dealing this tumor. PATIENT CONCERNS: In this report, we described a patient who suffered from plurihormonal pituitary adenomas, with concomitant prolactin (PRL) and growth hormone (GH) secretion. The adenomas showed aggressive behaviors, which was giant, invasive, and refractory to bromocriptine treatments. INTERVENTIONS: The patient underwent a surgical treatment. DIAGNOSIS: The pathology together with clinical presentation and blood hormone test confirmed that it was PRL-GH secreting tumors. OUTCOMES: Although a gross resection was achieved, the postoperative hormones were not normalized. There were also abundant programmed death ligand-1 proteins and CD8 lymphocyte infiltration in the tumor tissues. LESSONS: Our results indicated immunotherapy as a promising treatment for this tumor. More studies were needed to investigate the possibility of the immunotherapy in pituitary adenomas.


Assuntos
Adenoma/metabolismo , Antígeno B7-H1/metabolismo , Biomarcadores Tumorais/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Neoplasias Hipofisárias/metabolismo , Adenoma/patologia , Adenoma/cirurgia , Adulto , Humanos , Masculino , Neoplasias Hipofisárias/patologia , Neoplasias Hipofisárias/cirurgia
18.
Front Pharmacol ; 8: 730, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29093678

RESUMO

Background: Treatment of cancers with programmed cell death protein 1 (PD-1) pathway inhibitors can lead to immune-related adverse events (irAEs), which could be serious and even fetal. Therefore, clinicians should be aware of the characteristics of irAEs associated with the use of such drugs. Methods: The MEDLINE, EMBASE, and Cochrane databases were searched to find potential studies using the following strategies: anti-PD-1/PD-L1 treatment; irAEs; and cancer. R© package Meta was used to pool incidence. Results: Forty-six studies representing 12,808 oncologic patients treated with anti-PD-1/PD-L1 agents were included in the meta-analysis. The anti-PD-1/PD-L1 agents included nivolumab, pembrolizumab, atezolizumab, durvalumab, avelumab, and BMS-936559. The tumor types were melanomas, Hodgkin lymphomas, urothelial carcinomas, breast cancers, non-small cell lung cancers, renal cell carcinomas (RCC), colorectal cancers, and others. We described irAEs according to organ systems, namely, the skin (pruritus, rash, maculopapular rash, vitiligo, and dermatitis), endocrine system (hypothyroidism, hyperthyroidism, hypophysitis, thyroiditis, and adrenal insufficiency), digestive system (colitis, diarrhea, pancreatitis, and increased AST/ALT/bilirubin), respiratory system (pneumonitis, lung infiltration, and interstitial lung disease), and urinary system (increased creatinine, nephritis, and renal failure). In patients treated with the PD-1 signaling inhibitors, the overall incidence of irAEs was 26.82% (95% CI, 21.73-32.61; I2, 92.80) in any grade and 6.10% (95% CI, 4.85-7.64; I2, 52.00) in severe grade, respectively. The development of irAEs was unrelated to the dose of anti-PD-1/PD-L1 agents. The incidence of particular irAEs varied when different cancers were treated with different drugs. The incidence of death due to irAEs was around 0.17%. Conclusion: The occurrence of irAEs was organ-specific and related to drug and tumor types.

19.
J Colloid Interface Sci ; 485: 25-31, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-27639171

RESUMO

Herein, we present the first example of manganese carbonate (MnCO3) nanoparticles (NPs) featuring intrinsic photoluminescence (PL) and magnetic resonance (MR) imaging capacity by Terbium (Tb) doping. The Tb-doped MnCO3 NPs were prepared by one-step thermal decomposition of Mn-oleate precursor in the presence of Tb-oleate. The oleate capped Tb-doped MnCO3 NPs are in rhombohedral shape with an average size of about 13nm. When endowed with high water-dispersible via replacing oleate with carboxylic silane, the Tb-doped MnCO3 NPs exhibit distinct intrinsic PL originated from the doped Tb3+ ions. Meanwhile, the MR imaging capacity of Tb-doped MnCO3 NPs is well retained, as demonstrated by a high r1 relaxivity of 4.0428mM-1s-1 and a significant MR contrast enhancement effect towards tiny brain glioma in mice.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Carbonatos/química , Glioma/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Manganês/química , Térbio/química , Animais , Encéfalo/metabolismo , Encéfalo/ultraestrutura , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/ultraestrutura , Meios de Contraste/química , Meios de Contraste/farmacocinética , Glioma/metabolismo , Glioma/ultraestrutura , Luminescência , Medições Luminescentes , Camundongos , Camundongos Endogâmicos ICR , Nanopartículas/química , Nanopartículas/ultraestrutura , Ácido Oleico/química , Tamanho da Partícula , Silanos/química
20.
Artigo em Chinês | MEDLINE | ID: mdl-27255045

RESUMO

OBJECTIVE: To study the effects of graphene quantum dots (GQDs) on hematopoietic system in rats. METHODS: Thirty male SD rats were randomly divided into three groups (n = 10): control group, high dose group (10 mg/kg · d), low dose group (5 mg/kg · d), The rats in experimental group were intravenous injected with GQDs for 28 days and those in control group were injected with normal saline at the same volume. Routine blood and the function of liver and kidney were detected by instrument analysis. The cycle and apoptosis of bone marrow mononuclear cells (BMCs) were detected by FCM. The other three only healthy male SD rat bone marrow mononuclear cells (BMCs) were cultured by joining GQDs for 24 h, 48 h,72 h in vitro, the proliferation was assayed by CCK-8, the content of granulocyte macrophage colony stimulating factor (GM-CSF) from cultural supernatants were detected by ELISA. RESULTS: The amount of red blood cell and concentration of hemoglobin from experimental group were increased significantly compared with those of control groups (P < 0.05), the concentration of triglyceride and high density lipoprotein were decreased. DNA synthesis period was prolonged (P < 0.01), there was no significant difference in apoptosis. BMCs were promoted proliferation clearly after using GQDs for 72 h (P < 0.05). The content of GM-CSF was increased (P < 0.01) . CONCLUSION: GQDs may promote hematopoietic function in rats.


Assuntos
Células da Medula Óssea/efeitos dos fármacos , Grafite/farmacologia , Hematopoese/efeitos dos fármacos , Pontos Quânticos/química , Animais , Apoptose , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley
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