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1.
BMC Bioinformatics ; 24(1): 274, 2023 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-37403043

RESUMEN

BACKGROUND: N6-methyladenosine (m6A) and 5-methylcytosine (m5C) are the main RNA methylation modifications involved in the oncogenesis of cancer. However, it remains obscure whether m6A/m5C-related long non-coding RNAs (lncRNAs) affect the development and progression of low grade gliomas (LGG). METHODS: We summarized 926 LGG tumor samples with RNA-seq data and clinical information from The Cancer Genome Atlas and Chinese Glioma Genome Atlas. 105 normal brain samples with RNA-seq data from the Genotype Tissue Expression project were collected for control. We obtained a molecular classification cluster from the expression pattern of sreened lncRNAs. The least absolute shrinkage and selection operator Cox regression was employed to construct a m6A/m5C-related lncRNAs prognostic signature of LGG. In vitro experiments were employed to validate the biological functions of lncRNAs in our risk model. RESULTS: The expression pattern of 14 sreened highly correlated lncRNAs could cluster samples into two groups, in which various clinicopathological features and the tumor immune microenvironment were significantly distinct. The survival time of cluster 1 was significantly reduced compared with cluster 2. This prognostic signature is based on 8 m6A/m5C-related lncRNAs (GDNF-AS1, HOXA-AS3, LINC00346, LINC00664, LINC00665, MIR155HG, NEAT1, RHPN1-AS1). Patients in the high-risk group harbored shorter survival times. Immunity microenvironment analysis showed B cells, CD4 + T cells, macrophages, and myeloid-derived DC cells were significantly increased in the high-risk group. Patients in high-risk group had the worse overall survival time regardless of followed TMZ therapy or radiotherapy. All observed results from the TCGA-LGG cohort could be validated in CGGA cohort. Afterwards, LINC00664 was found to promote cell viability, invasion and migration ability of glioma cells in vitro. CONCLUSION: Our study elucidated a prognostic prediction model of LGG by 8 m6A/m5C methylated lncRNAs and a critical lncRNA regulation function involved in LGG progression. High-risk patients have shorter survival times and a pro-tumor immune microenvironment.


Asunto(s)
Glioma , ARN Largo no Codificante , Humanos , ARN Largo no Codificante/genética , Pronóstico , Glioma/genética , Carcinogénesis , 5-Metilcitosina , Microambiente Tumoral/genética
2.
Cell Mol Neurobiol ; 44(1): 14, 2023 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-38158515

RESUMEN

The existence of lymphatic vessels or similar clearance systems in the central nervous system (CNS) that transport nutrients and remove cellular waste is a neuroscientific question of great significance. As the brain is the most metabolically active organ in the body, there is likely to be a potential correlation between its clearance system and the pathological state of the CNS. Until recently the successive discoveries of the glymphatic system and the meningeal lymphatics solved this puzzle. This article reviews the basic anatomy and physiology of the glymphatic system. Imaging techniques to visualize the function of the glymphatic system mainly including post-contrast imaging techniques, indirect lymphatic assessment by detecting increased perivascular space, and diffusion tensor image analysis along the perivascular space (DTI-ALPS) are discussed. The pathological link between glymphatic system dysfunction and neurological disorders is the key point, focusing on the enlarged perivascular space (EPVS) and the index of diffusivity along the perivascular space (ALPS index), which may represent the activity of the glymphatic system as possible clinical neuroimaging biomarkers of neurological disorders. The pathological link between glymphatic system dysfunction and neurological disorders is the key point, focusing on the enlarged perivascular space (EPVS) and the index for of diffusivity along the perivascular space (ALPS index), which may represent the activity of the glymphatic system as possible clinical neuroimaging biomarkers of neurological disorders.


Asunto(s)
Sistema Glinfático , Enfermedades del Sistema Nervioso , Humanos , Sistema Glinfático/diagnóstico por imagen , Enfermedades del Sistema Nervioso/diagnóstico por imagen , Neuroimagen , Sistema Nervioso Central , Biomarcadores
3.
Neuroendocrinology ; 112(5): 417-426, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34034260

RESUMEN

Dopamine agonists (DAs) are preferred for the treatment of prolactinomas and are usually very effective. Nonetheless, 20-30% of bromocriptine- and approximately 10% of cabergoline-treated individuals exhibit resistance to DAs. In addition, the mechanism underlying this phenomenon remains elusive. In this study, we summarize the major findings regarding the role of microRNAs (miRNAs) in the pathogenesis of DA-resistant prolactinoma (DARP). Currently available evidence suggests that miRNAs are usually dysregulated in DARP and that, although controversial, the dysregulated miRNAs target the transforming growth factor (TGF)-ß, dopamine 2 receptor (D2R), or estradiol (E2)/estrogen receptor (ER) signaling pathways to mediate the therapeutic effect of DAs. These findings provide new incentives for research on innovative strategies for predicting patients' responsiveness to dopamine therapies and for developing treatment approaches. Unfortunately, recent studies tended to focus exclusively on the differential miRNA expression profiles between DARP and dopamine-sensitive prolactinoma, and no definitive consensus has been reached regarding the role of these miRNAs in the modulation mechanism. Therefore, current and future efforts should be directed toward the exploration of the mechanism underlying the dysregulation of miRNAs as well as of the target proteins that are affected by the dysregulated miRNAs. Furthermore, the modulation of the expression of dysregulated miRNAs, which target the D2R, TGF-ß, or E2/ER signaling pathways, might be a promising alternative to treat patients with DARP and improve their prognosis.


Asunto(s)
MicroARNs , Neoplasias Hipofisarias , Prolactinoma , Dopamina , Agonistas de Dopamina/farmacología , Agonistas de Dopamina/uso terapéutico , Resistencia a Antineoplásicos/genética , Humanos , MicroARNs/genética , Neoplasias Hipofisarias/tratamiento farmacológico , Neoplasias Hipofisarias/genética , Neoplasias Hipofisarias/metabolismo , Prolactinoma/tratamiento farmacológico , Prolactinoma/genética
4.
Neurosurg Rev ; 44(6): 3509-3517, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33839945

RESUMEN

COVID-19 has spread globally, causing a pandemic and medical interruptions. As more countries control the epidemic, the resumption of work is imperative. However, asymptomatic carriers become the main source of infection. After several months of recovery, Wuhan had much experience with facing the challenge of work resumption. The purpose of this study was to investigate the safety of the resumption strategies, as well as the outcome of the resumption efforts, in the early post-epidemic period. A retrospective study was conducted in patients admitted between April 8 and June 30 to the neurosurgery department of Tongji Hospital, Wuhan. The medical information, past medical history, COVID-19 tests, laboratory parameters, CT results, and management were reviewed and recorded. 768 patients were admitted to the neurosurgery department at Tongji Hospital, and none of them became new infections. Our department recovered to 70% efficiency one month after the resumption of work. Two patients were found to have asymptomatic infections in the outpatient department. Two patients who recovered from COVID-19 underwent the surgery without recurrence of COVID-19. Tumor patients accounted for more than 50% of the surgery patients in the early period. It is feasible and helpful to follow our strict admission algorithm in the early post-epidemic period, even though the challenges of asymptomatic infectors exist. Two COVID-19 tests in 3 days are suggested within the early period. Protective downgrades should be based on the testing of asymptomatic patients in the area. Recovered COVID-19 patients can undergo surgery without recurrence.


Asunto(s)
COVID-19 , Neurocirugia , China/epidemiología , Humanos , Pandemias , Estudios Retrospectivos , SARS-CoV-2
5.
Front Aging Neurosci ; 16: 1393841, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38912523

RESUMEN

Objective: The purpose of this study is to explore whether machine learning can be used to establish an effective model for the diagnosis of Parkinson's disease (PD) by using texture features extracted from cerebellar gray matter and white matter, so as to identify subtle changes that cannot be observed by the naked eye. Method: This study involved a data collection period from June 2010 to March 2023, including 374 subjects from two cohorts. The Parkinson's Progression Markers Initiative (PPMI) served as the training set, with control group and PD patients (HC: 102 and PD: 102) from 24 global sites. Our institution's data was utilized as the test set (HC: 91 and PD: 79). Machine learning was employed to establish multiple models for PD diagnosis based on texture features of the cerebellum's gray and white matter. Results underwent evaluation through 5-fold cross-validation analysis, calculating the area under the receiver operating characteristic curve (AUC) for each model. The performance of each model was compared using the Delong test, and the interpretability of the optimized model was further augmented by employing Shapley additive explanations (SHAP). Results: The AUCs for all pipelines in the validation dataset were compared using FeAture Explorer (FAE) software. Among the models established by Kruskal-Wallis (KW) and logistic regression via Lasso (LRLasso), the AUC was highest using the "one-standard error" rule. 'WM_original_glrlm_GrayLevelNonUniformity' was considered the most stable and predictive feature. Conclusion: The texture features of cerebellar gray matter and white matter combined with machine learning may have potential value in the diagnosis of Parkinson's disease, in which the heterogeneity of white matter may be a more valuable imaging marker.

6.
Neuro Oncol ; 26(1): 137-152, 2024 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-37555799

RESUMEN

BACKGROUND: Approximately 35% of pituitary adenoma (PA) display an aggressive profile, resulting in low surgical total resection rates, high recurrence rates, and worse prognosis. However, the molecular mechanism of PA invasion remains poorly understood. Although "a disintegrin and metalloproteinases" (ADAMs) are associated with the progression of many tumors, there are no reports on ADAM22 in PA. METHODS: PA transcriptomics databases and clinical specimens were used to analyze the expression of ADAM22. PA cell lines overexpressing wild-type ADAM22, the point mutation ADAM22, the mutated ADAM22 without disintegrin domain, and knocking down ADAM22 were generated. Cell proliferation/invasion assays, flow cytometry, immunohistochemistry, immunofluorescence, co-immunoprecipitation, mass spectrometry, Reverse transcription-quantitative real-time PCR, phos-tag SDS-PAGE, and Western blot were performed for function and mechanism research. Nude mice xenograft models and rat prolactinoma orthotopic models were used to validate in vitro findings. RESULTS: ADAM22 was significantly overexpressed in PA and could promote the proliferation, migration, and invasion of PA cells. ADAM22 interacted with integrin ß1 (ITGB1) and activated FAK/PI3K and FAK/ERK signaling pathways through its disintegrin domain to promote PA progression. ADAM22 was phosphorylated by PKA and recruited 14-3-3, thereby delaying its degradation. ITGB1-targeted inhibitor (anti-itgb1) exerted antitumor effects and synergistic effects in combination with somatostatin analogs or dopamine agonists in treating PA. CONCLUSIONS: ADAM22 was upregulated in PA and was able to promote PA proliferation, migration, and invasion by activating ITGB1 signaling. PKA may regulate the degradation of ADAM22 through post-transcriptional modification levels. ITGB1 may be a potential therapeutic target for PA.


Asunto(s)
Desintegrinas , Neoplasias Hipofisarias , Ratones , Humanos , Animales , Ratas , Integrina beta1/metabolismo , Ratones Desnudos , Metaloproteasas , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular
7.
Int J Biol Sci ; 20(2): 801-817, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38169563

RESUMEN

Somatostatin analogues (SSTA) are first-line pharmacological treatment choice for acromegaly, which received satisfying tumor shrinkage and normalization of growth hormone. However, there are still patients unresponsive to SSTA, and the underline mechanism remains unknown. Besides, there is no evidence regarding the role of endoplasmic reticulum stress (ERS) and its transmission in SSTA resistance, which also require investigation. Primary growth hormone adenoma cells and cell lines were treated with SSTA; autophagy double-labeled LC3 (mRFP-GFP) adenovirus transfection, flow cytometry sorting, western blotting, calcium imaging as well as immunofluorescence staining were used to determine ERS and autophagy signal transmission; xenograft and syngeneic tumor in vivo model were exploited to confirm the ERS signal transmission mediated effect. Our results revealed that SSTA induces ERS in pituitary growth hormone (GH) adenoma cells. The ERS signals can be intercellularly transmitted, leading to less responsible to SSTA treatment. Moreover, SSTA stimulates inositol triphosphate (IP3) elevation, mediating ERS intercellular transfer. In addition, connexin 36 tunnels ERS transmission, and its blocker, Quinine, exhibits a synergistic effect with SSTA treating GH adenoma. Our study provided insight into ERS intercellular transmission mediated SSTA resistance, which could be translated into clinical usage to improve SSTA efficiency in GH adenoma treatment.


Asunto(s)
Adenoma , Neoplasias Hipofisarias , Humanos , Somatostatina/farmacología , Somatostatina/uso terapéutico , Hormona del Crecimiento/metabolismo , Hormona del Crecimiento/uso terapéutico , Neoplasias Hipofisarias/tratamiento farmacológico , Neoplasias Hipofisarias/genética , Neoplasias Hipofisarias/metabolismo , Proteína delta-6 de Union Comunicante , Adenoma/tratamiento farmacológico , Estrés del Retículo Endoplásmico
8.
Biomed Res Int ; 2023: 6082635, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36685667

RESUMEN

Glycosylation is the most common posttranslational modification of proteins. Glycosyltransferase gene differential expression dictates the glycosylation model and is epigenetically regulating glioma progression and immunity. This study is aimed at identifying the glycosyltransferase gene signature to predict the prognosis and immune characteristics of glioma. The glycosyltransferase gene signature of glioma was identified in the TCGA database and validated in the CGGA database. Glioma patients were then divided into high- and low-risk groups based on risk scores to compare survival differences and predictive capacity. Subsequently, validation of glycosyltransferase gene signature merits by comparing with other signatures and utility in clinical judgment. The immune cell infiltration, immune pathways, and immune checkpoint expression level were also analyzed and compared in the high- and low-risk groups. Finally, the signature and its gene function were tested in our cohort and in vitro experiments. Eight glycosyltransferase genes were identified to establish the glycosyltransferase signature to predict the prognosis of glioma patients. The survival time was shorter in the high-risk group compared to the low-risk group based on glycosyltransferase signature and was confirmed in an independent external cohort. The glycosyltransferase signature displayed outstanding predictive capacity than other signatures in the TCGA and CGGA database cohorts. Furthermore, patients in the high-risk group were positively correlated with TAM infiltration, immune checkpoint expression level, and protumor immune pathways in TCGA cohorts. Validation of clinical tissue specimens revealed that the high-risk group was closely associated with infiltration of M2 TAMs. High-risk genes in the signature promote glioma proliferation, invasion, and macrophage recruitment in an in vitro validation of U87 and U251 cell lines. This carefully constructed that glycosyltransferase signature can predict the prognosis and immune profile of gliomas and help us evaluate subsequent macrophage-targeted therapies as well as other immune microenvironment modulation therapeutic strategies.


Asunto(s)
Glioma , Glicosiltransferasas , Humanos , Glicosiltransferasas/genética , Pronóstico , Glicosilación , Fenotipo , Glioma/genética , Microambiente Tumoral/genética
9.
Cancers (Basel) ; 15(13)2023 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-37444485

RESUMEN

TAF participated in the progression of various cancers, including PA via the release of soluble factors. Exosomes belonged to extracellular vesicles, which were revealed as a crucial participator in intercellular communication. However, the expression pattern and effect of TAF-derived exosomes remained largely unknown in PA. In the present study, we performed in silico analysis based on public RNA-seq datasets to generate the circRNA/miRNA regulatory network. The qRT-PCR, Western blotting, RNA pull-down, and luciferase assay were performed to investigate the effect of TAF-derived exosomes. TAF-derived exosomal circDennd1b was significantly upregulated in PA and promoted the proliferation, migration, and invasion of PA cells via sponging miR-145-5p in PA cells. In addition, miR-145-5p directly regulated One Cut homeobox 2 (ONECUT2/OC2) expression and inhibited the promoting effect of ONECUT2 on PA. We further demonstrated that ONECUT2 transcriptionally increased fibroblast growth factor receptor 3 (FGFR3) expression, which further activates the mitogen-activated protein kinases (MAPK) pathway, thus promoting PA progression. Moreover, the suppression of TAFs by ABT-263 and ONECUT2 by CSRM617 inhibited the growth of PA. In conclusion, our study illustrated that TAF-derived exosomal circDennd1b affected PA progression via regulating ONECUT2 expression, which provides a potential therapeutic strategy against aggressive PA.

10.
Front Oncol ; 12: 822085, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35600367

RESUMEN

It is commonly recognized, that glioblastoma is a large complex composed of neoplastic and non-neoplastic cells. Tumor-associated macrophages account for the majority of tumor bulk and play pivotal roles in tumor proliferation, migration, invasion, and survival. There are sophisticated interactions between malignant cells and tumor associated-macrophages. Tumor cells release a variety of chemokines, cytokines, and growth factors that subsequently lead to the recruitment of TAMs, which in return released a plethora of factors to construct an immunosuppressive and tumor-supportive microenvironment. In this article, we have reviewed the biological characteristics of glioblastoma-associated macrophages and microglia, highlighting the emerging molecular targets and related signal pathways involved in the interaction between TAMs and glioblastoma cells, as well as the potential TAMs-associated therapeutic targets for glioblastoma.

11.
Front Cell Infect Microbiol ; 12: 781315, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35174105

RESUMEN

Spinal tuberculosis (TB), the most common form of musculoskeletal tuberculosis, is an infection-related disease globally, with paraplegia occurring in severe cases. Therefore, identification of spinal TB at an early stage is important for early intervention and eventual therapy. In this study, we conducted a prospective cohort study in routine clinical practice to investigate the diagnosis of different TB tests. A total of 519 patients were recruited based on the radiology of spinal TB. The diagnostic model was computed by regression analysis and was determined by receiver operating characteristic (ROC) curve analysis. Specificity, sensitivity, predictive value, likelihood ratio, and accuracy were also computed and compared. GeneXpert MTB/RIF showed a higher positive rate compared to that in the acid-fast bacilli smear and Mycobacterium culture. The results also showed that the Mycobacterium tuberculosis-specific antigen/phytohemagglutinin ratio in the T-SPOT assay had a good performance in the preoperative diagnosis and prediction of spinal TB. The diagnostic model based on the ratio of tuberculosis-specific antigen/phytohemagglutinin combined with GeneXpert MTB/RIF showed better efficiency for spinal TB diagnosis. In summary, the tuberculosis-specific antigen/phytohemagglutinin ratio combined with GeneXpert MTB/RIF could provide an early diagnosis of spinal TB.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis de la Columna Vertebral , Diagnóstico Precoz , Humanos , Mycobacterium tuberculosis/genética , Fitohemaglutininas , Estudios Prospectivos , Rifampin , Sensibilidad y Especificidad , Esputo/microbiología , Tuberculosis de la Columna Vertebral/diagnóstico
12.
Front Oncol ; 12: 844144, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35371978

RESUMEN

Gliomas are the most aggressive primary intracranial malignancies with poor overall survival. ITGA5 is one member of the integrin adhesion molecule family and is implicated in cancer metastasis and oncogenesis. However, few studies have explored the association between tumor immune microenvironment and ITGA5 expression level in gliomas. Firstly, we analyzed 3,047 glioma patient samples collected from the TCGA, the CGGA, and the GEO databases, proving that high ITGA5 expression positively related to aggressive clinicopathological features and poor survival in glioma patients. Then, based on the ITGA5 level, immunological characteristics and genomic alteration were explored through multiple algorithms. We observed that ITGA5 was involved in pivotal oncological pathways, immune-related processes, and distinct typical genomic alterations in gliomas. Notably, ITGA5 was found to engage in remolding glioma immune infiltration and immune microenvironment, manifested by higher immune cell infiltration when ITGA5 is highly expressed. We also demonstrated a strong correlation between ITGA5 and immune checkpoint molecules that may be beneficial from immune checkpoint blockade strategies. In addition, ITGA5 was found to be a robust and sensitive indicator for plenty of chemotherapy drugs through drug sensitivity prediction. Altogether, our comprehensive analyses deciphered the prognostic, immunological, and therapeutic value of ITGA5 in glioma, thus improving individual and precise therapy for combating gliomas.

13.
Cancers (Basel) ; 14(19)2022 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-36230833

RESUMEN

Standard chemotherapy of Glioblastoma multiforme (GBM) using temozolomide (TMZ) frequently fails due to acquired chemoresistance. Tumor-associated macrophages and microglia (TAMs) as major immune cell population in the tumor microenvironment are potential modulators of TMZ response. However; little is known about how TAMs participate in TMZ induced chemoresistance. Members of the metzincin superfamily such as Matrix Metalloproteases (MMPs) and A Disintegrin and Metalloprotease (ADAM) proteases are important mediators of cellular communication in the tumor microenvironment. A qPCR screening was performed to identify potential targets within the ADAM and MMP family members in GBM cells. In co-culture with macrophages ADAM8 was the only signature gene up-regulated in GBM cells induced by macrophages under TMZ treatment. The relationship between ADAM8 expression and TAM infiltration in GBM was determined in a patient cohort by qPCR; IF; and IHC staining and TCGA data analysis. Moreover; RNA-seq was carried out to identify the potential targets regulated by ADAM8. CCL2 expression levels were determined by qPCR; Western blot; IF; and ELISA. Utilizing qPCR; IF; and IHC staining; we observed a positive relationship between ADAM8 expression and TAMs infiltration level in GBM patient tissues. Furthermore; ADAM8 induced TAMs recruitment in vitro and in vivo. Mechanistically; we revealed that ADAM8 activated HB-EGF/EGFR signaling and subsequently up-regulated production of CCL2 in GBM cells in the presence of TMZ treatment; promoting TAMs recruitment; which further induced ADAM8 expression in GBM cells to mediate TMZ chemoresistance. Thus; we revealed an ADAM8 dependent positive feedback loop between TAMs and GBM cells under TMZ treatment which involves CCL2 and EGFR signaling to cause TMZ resistance in GBM.

14.
Cell Death Dis ; 12(12): 1145, 2021 12 09.
Artículo en Inglés | MEDLINE | ID: mdl-34887381

RESUMEN

Glioma is the most common and fatal tumor of the central nervous system in humans. Despite advances in surgery, radiotherapy, and chemotherapeutic agents, glioma still has a poor prognosis. The tumor microenvironment (TME) of glioma is of highly complex heterogeneity, which relies on a network-based communication between glioma cells and other stromal cell types. Exosomes are the most common type of naturally occurring extracellular vesicles, ranging in size from 40 to 160 nm, and can serve as carriers for proteins, RNAs, and other biologically active molecules. Recent evidence has shown that glioma-derived exosomes (GDEs) can be integrally detected in the local tissue and circulatory blood samples, and also can be transferred to recipient cells to mediate transmission of genetic information. Non-coding RNAs (ncRNAs) mainly including microRNA, long non-coding RNA, and circular RNA, account for a large portion of the human transcriptome. A broad range of ncRNAs encapsulated in GDEs is reported to exert regulatory functions in various pathophysiological processes of glioma. Herein, this review summarizes the latest findings on the fundamental roles of GDE ncRNAs that have been implicated in glioma behaviors, immunological regulation, diagnosis potential, and treatment resistance, as well as the current limitations and perspectives. Undoubtedly, a thorough understanding of this area will provide comprehensive insights into GDE-based clinical applications for combating gliomas.


Asunto(s)
Exosomas , Glioma , MicroARNs , Resistencia a Medicamentos , Exosomas/metabolismo , Glioma/genética , Glioma/patología , Humanos , MicroARNs/genética , MicroARNs/metabolismo , ARN no Traducido/genética , ARN no Traducido/metabolismo , Microambiente Tumoral/genética
15.
Br J Pharmacol ; 178(17): 3570-3586, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33904172

RESUMEN

BACKGROUND AND PURPOSE: Dopamine agonists targeting D2 receptor have been used for decades in treating pituitary adenomas. There has been little clear evidence implicating the canonical G protein signalling as the mechanism by which D2 receptor suppresses the growth of pituitary tumours. We hypothesize that ß-arrestin2-dependent signalling is the molecular mechanism dictating D2 receptor inhibitory effects on pituitary tumour growth. EXPERIMENTAL APPROACH: The involvement of G protein and ß-arrestin2 in bromocriptine-mediated growth suppression in rat MMQ and GH3 tumour cells was assessed. The anti-growth effect of a ß-arrestin2-biased agonist, UNC9994, was tested in cultured cells, tumour-bearing nude mice and primary cultured human pituitary adenomas. The effect of G protein signalling on tumour growth was also analysed by using a G protein-biased agonist, MLS1547, and a Gßγ inhibitor, gallein, in vitro. KEY RESULTS: ß-arrestin2 signalling but not G protein pathways mediated the suppressive effect of bromocriptine on pituitary tumour growth. UNC9994 inhibited pituitary tumour cell growth in vitro and in vivo. The suppressive function of UNC9994 was obtained by inducing intracellular reactive oxygen species generation through downregulating mitochondrial complex I subunit NDUFA1. The effects of Gαi/o signalling and Gßγ signalling via D2 receptor on pituitary tumour growth were cell-type-dependent. CONCLUSION AND IMPLICATIONS: Given the very low expression of Gαi/o proteins in pituitary tumours and the complexity of the responses of pituitary tumours to G protein signalling pathways, our study reveals D2 receptor ß-arrestin2-biased ligand may be a more promising choice to treat pituitary tumours with improved therapeutic selectivity.


Asunto(s)
Neoplasias Hipofisarias , Animales , Agonistas de Dopamina/farmacología , Ratones , Ratones Desnudos , Neoplasias Hipofisarias/tratamiento farmacológico , Ratas , Receptores de Dopamina D2/metabolismo , Arrestina beta 2/metabolismo
16.
J Thromb Thrombolysis ; 28(2): 132-9, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19543696

RESUMEN

Unfractionated heparin (UFH) enhances antithrombin (AT) inhibition of thrombin (IIa) and factor Xa (FXa). Low molecular weight heparins (LMWH) primarily enhance AT inhibition of FXa. M118 is a LMWH produced from UFH and retains its ability to promote both FXa and IIa inhibition. We tested the hypothesis that M118 has anticoagulant activities similar to UFH in an in vitro model of coagulation. Platelet IIa generation was assessed in a cell-based model that mimics aspects of coagulation in vivo. Inhibition of IIa generation as a function of concentration was steeper for UFH than Lovenox. The effect of M118 closely paralleled that of UFH. By contrast, M118 did not prolong the aPTT to as great a degree as UFH, though both prolonged the aPTT more than did Lovenox. Our data suggest that the ability to inhibit platelet surface IIa generation correlates with the therapeutic level of heparins and confirms similarities between the anticoagulant properties of M118 and UFH.


Asunto(s)
Anticoagulantes/farmacología , Plaquetas/efectos de los fármacos , Heparina de Bajo-Peso-Molecular/farmacología , Modelos Biológicos , Monocitos/efectos de los fármacos , Trombina/biosíntesis , Bioensayo , Enoxaparina/farmacología , Inhibidores del Factor Xa , Humanos , Tiempo de Tromboplastina Parcial
17.
Medicine (Baltimore) ; 96(15): e6603, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28403103

RESUMEN

RATIONALE: Primary bone lymphoma (PBL) is a rare malignant entity. There is a better survival of PBL than any other malignant bone tumors and extranodal lymphomas. PATIENT CONCERNS: We report a rare case of PBL involving radius and tibia. The patient was a 14-year-old girl with left forearm pain and swelling after trauma. Six months later after the last chemotherapy and radiotherapy, pain and swelling of left knee was presented. DIAGNOSES: Radiological imaging revealed a lytic destruction, periosteal reaction, and pathological fracture of radius and tibia with soft tissue mass. Surgical biopsy was performed, and the result of histopathological diagnosis was diffused large B-cell lymphoma (stage IV, group A). INTERVENTION: Chemotherapy combined with radiotherapy was applied before curation. LESSONS: Due to its uncommon presentation, PBL should be taken into consideration if differential diagnosis from other bone tumors is necessary in clinic.


Asunto(s)
Neoplasias Óseas/patología , Linfoma de Células B Grandes Difuso/patología , Radio (Anatomía) , Tibia , Adolescente , Femenino , Humanos
18.
Semin Thromb Hemost ; 28(1): 67-78, 2002 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11885027

RESUMEN

This article focuses on the emerging views and concepts concerning the role of cell surface and extracellular heparan sulfate-like glycosaminoglycans (HSGAGs) in tumor biology. HSGAGs, found ubiquitously both at the cell surface and in the extracellular matrix (ECM), play a critical role in regulating tumor initiation, progression, and metastasis. The diverse biological functions of HSGAGs include the regulation of coagulation, growth factor signaling, cell adhesion, proliferation, and mobility. HSGAGs, depending on their location (anchored at the cell surface or soluble as free GAGs), the signaling molecules they associate with, and their fine structures, can either promote or inhibit the tumorigenic process.


Asunto(s)
Proteoglicanos de Heparán Sulfato/fisiología , Metástasis de la Neoplasia/patología , Neoplasias/patología , Matriz Extracelular/química , Matriz Extracelular/fisiología , Glicosaminoglicanos/química , Glicosaminoglicanos/farmacología , Glicosaminoglicanos/fisiología , Proteoglicanos de Heparán Sulfato/química , Proteoglicanos de Heparán Sulfato/farmacología , Humanos , Neoplasias/etiología , Transducción de Señal
19.
Proc Natl Acad Sci U S A ; 101(26): 9867-72, 2004 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-15226520

RESUMEN

Although heparin and low-molecular-weight heparins (LMWH) have been widely used clinically as anticoagulants, their broader use has been limited by the lack of noninvasive delivery methods for this class of molecules. In this study, we demonstrate an efficient, rapid, and reproducible delivery system for heparin through the lungs that is not confined to particles of a certain geometric or aerodynamic diameter. Importantly, blood levels after intrapulmonary administration of either heparin or LMWH were comparable to that of s.c. administration but are characterized by a more rapid onset of action (t(1/2) = 40 min vs. 2.5 h, respectively). Furthermore, we show in animal models, that inhaled heparin species efficiently inhibit diseases such as thrombosis and emphysema, and that the repetitive inhalation of formulated LMWH results in no observable toxicity from the delivery of reproducible systemic levels of heparin or LMWH.


Asunto(s)
Aerosoles/administración & dosificación , Heparina de Bajo-Peso-Molecular/administración & dosificación , Heparina de Bajo-Peso-Molecular/farmacocinética , Heparina/administración & dosificación , Heparina/farmacocinética , Pulmón/metabolismo , Absorción , Administración por Inhalación , Aerosoles/efectos adversos , Aerosoles/farmacocinética , Aerosoles/uso terapéutico , Animales , Disponibilidad Biológica , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Enfisema/tratamiento farmacológico , Heparina/efectos adversos , Heparina/sangre , Heparina de Bajo-Peso-Molecular/efectos adversos , Heparina de Bajo-Peso-Molecular/sangre , Masculino , Tamaño de la Partícula , Conejos , Ratas , Ratas Sprague-Dawley , Trombosis/tratamiento farmacológico , Trombosis/prevención & control , Factores de Tiempo
20.
Proc Natl Acad Sci U S A ; 100(2): 651-6, 2003 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-12525684

RESUMEN

Heparin and low-molecular weight heparins (LMWHs), complex, sulfated polysaccharides isolated from endogenous sources, are potent modulators of hemostasis. Heparin and LMWHs interact with multiple components of the coagulation cascade to inhibit the clotting process. Pharmaceutical preparations of these complex polysaccharides, typically isolated from porcine intestinal mucosa, are heterogeneous in length and composition and, hence, highly polydisperse. Because of the structural heterogeneity of heparin and LMWHs, correlating their activity with a particular structure or structural motif has been a challenging task. Herein, we demonstrate a practical analytical method that enables the measurement of a structural correlate to in vivo anticoagulant function. With this understanding we have developed LMWHs with increased anticoagulant activity and decreased polydispersity. In addition to the pronounced anti-Xa and anti-IIa activity of these LMWHs, we also demonstrate that they possess desirable in vivo pharmacokinetic properties, the ability to cause the release of tissue factor pathway inhibitor (TFPI) from the endothelium, complete bioavailability through s.c. delivery, and the ability to inhibit both venous and arterial thromboses. Importantly, from a clinical safety point of view, unlike LMWHs presently used in the clinic, we show that these LMWHs are rapidly and completely neutralized by protamine. Together, the findings presented herein demonstrate a facile approach for the creation of designer LMWHs with optimal activity profiles.


Asunto(s)
Anticoagulantes/farmacología , Diseño de Fármacos , Heparina de Bajo-Peso-Molecular/farmacología , Animales , Antitrombina III/metabolismo , Antitrombina III/farmacología , Heparina de Bajo-Peso-Molecular/farmacocinética , Masculino , Protaminas/farmacología , Conejos , Ratas , Ratas Sprague-Dawley , Relación Estructura-Actividad , Trombosis/prevención & control , Trombosis de la Vena/prevención & control
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