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1.
J Magn Reson Imaging ; 58(4): 1234-1242, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-36727433

RESUMO

BACKGROUND: Genetic testing for molecular markers of gliomas sometimes is unavailable because of time-consuming and expensive, even limited tumor specimens or nonsurgery cases. PURPOSE: To train a three-class radiomic model classifying three molecular subtypes including isocitrate dehydrogenase (IDH) mutations and 1p/19q-noncodeleted (IDHmut-noncodel), IDH wild-type (IDHwt), IDH-mutant and 1p/19q-codeleted (IDHmut-codel) of adult gliomas and investigate whether radiomic features from diffusion-weighted imaging (DWI) could bring additive value. STUDY TYPE: Retrospective. POPULATION: A total of 755 patients including 111 IDHmut-noncodel, 571 IDHwt, and 73 IDHmut-codel cases were divided into training (n = 480) and internal validation set (n = 275); 139 patients including 21 IDHmut-noncodel, 104 IDHwt, and 14 IDHmut-codel cases were utilized as external validation set. FIELD STRENGTH/SEQUENCE: A 1.5 T or 3.0 T/multiparametric MRI, including T1-weighted (T1), T1-weighted gadolinium contrast-enhanced (T1c), T2-weighted (T2), fluid attenuated inversion recovery (FLAIR), and DWI. ASSESSMENT: The performance of multiparametric radiomic model (random-forest model) using 22 selected features from T1, T2, FLAIR, T1c images and apparent diffusion coefficient (ADC) maps, and conventional radiomic model using 20 selected features from T1, T2, FLAIR, and T1c images was assessed in internal and external validation sets by comparing probability values and actual incidence. STATISTICAL TESTS: Mann-Whitney U test, Chi-Squared test, Wilcoxon test, receiver operating curve (ROC), and area under the curve (AUC); DeLong analysis. P < 0.05 was statistically significant. RESULTS: The multiparametric radiomic model achieved AUC values for IDHmut-noncodel, IDHwt, and IDHmut-codel of 0.8181, 0.8524, and 0.8502 in internal validation set and 0.7571, 0.7779, and 0.7491 in external validation set, respectively. Multiparametric radiomic model showed significantly better diagnostic performance after DeLong analysis, especially in classifying IDHwt and IDHmut-noncodel subtypes. DATA CONCLUSION: Radiomic features from DWI could bring additive value and improve the performance of conventional MRI-based radiomic model for classifying the molecular subtypes especially IDHmut-noncodel and IDHwt of adult gliomas. TECHNICAL EFFICACY: Stage 2.


Assuntos
Neoplasias Encefálicas , Glioma , Adulto , Humanos , Neoplasias Encefálicas/patologia , Estudos Retrospectivos , Glioma/patologia , Imageamento por Ressonância Magnética/métodos , Algoritmos , Mutação , Isocitrato Desidrogenase/genética
2.
Life Sci ; 280: 119695, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34111463

RESUMO

AIMS: Rational design of protein scaffolds with specific biological functions/activities has attracted much attention over the past decades. In the present study, we systematically examine the trimer-of-hairpins (TOH) motif of human respiratory syncytial virus (RSV) F protein, which plays a central role in viral membrane fusion and is a coiled-coil six-helix bundle formed by the antiparallel intermolecular interaction between three N-terminal heptad-repeat (HRN) helices and three C-terminal heptad-repeat (HRC) helices. MAIN METHODS: A rational strategy that integrates dynamics simulation, thermodynamics calculation, fluorescence polarization and circular dichroism is proposed to design HRC-targeted α-helical hairpin traps based on the crystal template of HRN core. KEY FINDINGS: The designed hairpin traps possess a typical helix-turn-helix scaffold that can be stabilized by stapling a disulfide bridge across its helical arms, which are highly structured (helicity >60%) and can mimic the native spatial arrangement of HRN helices in TOH motif to trap the hotspot sites of HRC with effective affinity (Kd is up to 6.4 µM). SIGNIFICANCE: The designed α-helical hairpin traps can be used as lead entities for further developing TOH-disrupting agents to target RSV membrane fusion event and the proposed rational design strategy can be readily modified to apply for other type I viruses.


Assuntos
Infecções por Vírus Respiratório Sincicial/metabolismo , Vírus Sincicial Respiratório Humano/fisiologia , Proteínas Virais de Fusão/metabolismo , Humanos , Fusão de Membrana , Modelos Moleculares , Conformação Proteica em alfa-Hélice , Multimerização Proteica , Vírus Sincicial Respiratório Humano/química , Proteínas Virais de Fusão/química
3.
Biochimie ; 176: 128-137, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32721503

RESUMO

Although a variety of tyrosine kinase inhibitors (TKIs) have been developed to target human epidermal growth factor receptor (EGFR) for lung cancer therapy, many patients treated with first-line small-molecule TKIs are clinically observed to eventually establish drug-resistant mutations T790 M and C797S around kinase active site, which play a primary role in development of acquired drug resistance to first-generation reversible and second-generation irreversible TKIs, respectively. Here, instead of developing small-molecule drugs to directly target the active site, we attempt to derive self-inhibitory peptides (SIPs) from the EGFR:EGFR asymmetric dimerization interface, where is separated from kinase active site and has a relatively low conservation as compared to the active site. It is found that the dimerization is a typical peptide-mediated protein interaction, where the first EGFR N-lobe adopts an N-terminal binding sequence (nBS) to interact with the dimerization interface of second EGFR C-lobe. A core binding sequence (nCBS, 676NQALLRILKE68) is identified in the nBS region as hotspot segment, which is then rationally optimized to generate a number of SIPs. Consequently, three designed SIPs are determined as promising candidates; they have high affinity to EGFR kinase domain, strong competitive potency with native nBS peptide for the dimerization interface, and effective cytotoxicity on human lung cancer cell lines. It is also demonstrated that these peptides are insensitive to drug-resistant EGFR T790 M/C797S mutation at molecular and cellular levels, and exhibit a good selectivity for EGFR over HER2 at molecular level.


Assuntos
Dimerização , Resistencia a Medicamentos Antineoplásicos , Neoplasias Pulmonares/tratamento farmacológico , Proteínas de Neoplasias/química , Peptídeos/química , Inibidores de Proteínas Quinases/química , Domínio Catalítico , Receptores ErbB/química , Receptores ErbB/metabolismo , Humanos , Neoplasias Pulmonares/metabolismo , Proteínas de Neoplasias/metabolismo , Peptídeos/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico
4.
Sci Rep ; 9(1): 13239, 2019 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-31519974

RESUMO

Inflammation and immunoreaction markers were correlated with the survival of patients in many tumors. However, there were no reports investigating the relationships between preoperative hematological markers and the prognosis of medulloblastoma (MB) patients based on the molecular subgroups (WNT, SHH, Group 3, and Group 4). A total 144 MB patients were enrolled in the study. The differences of preoperative hematological markers among molecular subgroups of MB were compared by One-way ANOVA method. Kaplan-Meier method was used to calculate the curves of progression free survival (PFS) and overall survival (OS). The comparison of survival rates in different groups were conducted by the Log-rank test. Multivariate analysis was used to evaluate independent prognostic factors. Increased preoperative NLR (neutrophil-to-lymphocyte ratio, PFS, P = 0.004, OS, P < 0.001) and PLR (platelet-to-lymphocyte ratio, PFS, P = 0.028, OS, P = 0.003) predicted poor prognosis in patients with MB, while preoperative MLR (monocyte-to-lymphocyte ratio), MPV (mean platelet volume), PDW (platelet distribution width), and AGR (albumin-to-globulin ratio) were revealed no predictive value on the prognosis of patients with MB. Furthermore, high preoperative NLR and PLR predicted unfavorable prognosis in childhood MB patients. However, preoperative NLR and PLR were not associated with the prognosis in adult MB patients. Multivariate analysis demonstrated preoperative NLR (PFS, P = 0.029, OS, P = 0.005) and PLR (PFS, P = 0.023, OS, P = 0.005) were the independent prognostic factors in MB patients. Emphatically, the levels of preoperative NLR and PLR in Group 3 MB were significantly higher than those in WNT MB. High preoperative NLR was associated with unfavorable OS in Group 3 (P = 0.032) and Group 4 (P = 0.027) tumors. Similarly, increased preoperative PLR predicted poor PFS (P = 0.012) and OS (P = 0.009) in Group 4 tumors. Preoperative NLR and PLR were the potential prognostic markers for MB patients. Preoperative NLR and PLR were significantly associated with the survival of Group 3 and Group 4 tumors.


Assuntos
Biomarcadores Tumorais/análise , Plaquetas/patologia , Neoplasias Cerebelares/patologia , Linfócitos/patologia , Meduloblastoma/patologia , Cuidados Pré-Operatórios , Adolescente , Adulto , Neoplasias Cerebelares/cirurgia , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Masculino , Meduloblastoma/cirurgia , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Adulto Jovem
5.
Aging (Albany NY) ; 11(16): 6252-6272, 2019 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-31444316

RESUMO

The prediction of clinical outcome for patients with infiltrative gliomas is challenging. Although preoperative hematological markers have been proposed as predictors of survival in glioma and other cancers, systematic investigations that combine these data with other relevant clinical variables are needed to improve prognostic accuracy and patient outcomes. We investigated the prognostic value of preoperative hematological markers, alone and in combination with molecular pathology, for the survival of 592 patients with Grade II-IV diffuse gliomas. On univariate analysis, increased neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and monocyte-to-lymphocyte ratio (MLR), and decreased albumin-to-globulin ratio (AGR), all predicted poor prognosis in Grade II/III gliomas. Multivariate analysis incorporating tumor status based on the presence of IDH mutations, TERT promoter mutations, and 1p/19q codeletion showed that in lower-grade gliomas, high NLR predicted poorer survival for the triple-negative, IDH mutation only, TERT mutation only, and IDH and TERT mutation groups. NLR was an independent prognostic factor in Grade IV glioma. We therefore propose a prognostic model for diffuse gliomas based on the presence of IDH and TERT promoter mutations, 1p/19q codeletion, and NLR. This model classifies lower-grade gliomas into nine subgroups that can be combined into four main risk groups based on survival projections.


Assuntos
Biomarcadores Tumorais/sangue , Neoplasias Encefálicas/sangue , Neoplasias Encefálicas/patologia , Glioma/sangue , Glioma/patologia , Patologia Molecular , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Prognóstico , Fatores de Risco
6.
J Clin Neurosci ; 67: 234-238, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31221576

RESUMO

During neurological surgery, neurosurgeons have to transform the two-dimensional (2D) sectional images into three-dimensional (3D) structures at the cognitive level. The complexity of the intracranial structures increases the difficulty and risk of neurosurgery. Mixed reality (MR) applications reduce the obstacles in the transformation from 2D images to 3D visualization of anatomical structures of central nervous system. In this study, the holographic image was established by MR using computed tomography (CT), computed tomography angiography (CTA) and magnetic resonance imaging (MRI) data of patients. The surgeon's field of vision was superimposed with the 3D model of the patient's intracranial structure displayed on the mixed reality head-mounted display (MR-HMD). The neurosurgeons practiced and evaluated the feasibility of this technique in neurosurgical cases. We developed the segmentation image masks and texture mapping including brain tissue, intracranial vessels, nerves, tumors, and their relative positions by MR technologies. The results showed that the three-dimensional imaging is in a stable state in the operating room with no significant flutter and blur. And the neurosurgeon's feedback on the comfort of the equipment and the practicality of the technology was satisfactory. In conclusion, MR technology can holographically construct a 3D digital model of patient's lesions and improve the anatomical perception of neurosurgeons during craniotomy. The feasibility of the MR-HMD application in neurosurgery is confirmed.


Assuntos
Craniotomia/métodos , Holografia/métodos , Cirurgia Assistida por Computador/métodos , Idoso , Neoplasias Encefálicas/cirurgia , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X/métodos
7.
Medicine (Baltimore) ; 97(50): e13675, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30558073

RESUMO

Glioma is the most common malignant tumor in the central nervous system (CNS). Lower-grade gliomas (LGG) refer to Grade II and III gliomas. In LGG patients, seizure often appears as an initial symptom and play an important role in clinical performance and quality of life of the patients. To date, the relationship between the onset of seizures and the molecular pathology in gliomas is still poorly investigated. In this study, we investigate the potential relationship between isocitrate dehydrogenase (IDH)/telomerase reverse transcriptase promoter (TERTp) mutations and preoperative seizures in patients with LGG. 289 adult LGG patients were enrolled in this study. Data of clinical characteristics and molecular pathology were acquired. Sanger sequencing was used to detect IDH/TERTp mutations. Chi-square test was performed to determine if the IDH/TERTp mutations were associated with seizures and seizure types. In 289 LGG patients, preoperative seizures accounted for 25.3% (73/289), IDH mutations accounted for 34.3%(99/289), and TERTp mutations accounted for 44.3% (128/289). The correlation analysis demonstrated that IDH mutation is a significant factor influencing the occurrence of tumor-related epilepsy (P <.001, chi-square test). On the other hand, the statistical analysis revealed no significant correlation between TERTp mutations and seizure in LGG patients (P = .102, chi-square test). The tumor-related epilepsy rates vary among different subgroups according to IDH/TERTp mutations. However, there is no definite correlation between the IDH (P = 1.000, chi-square test)/TERTp (P = .613, chi-square test) mutations and the types of epileptic seizure. IDH mutations are more common in preoperative LGG patients with epileptic symptoms, suggesting that this mutation is positively correlated with seizures. However, there was no significant correlation between TERTp mutations and seizures. Different molecular pathologic types based on IDH/TERTp have different incidences of tumor-associated epilepsy in LGGs.


Assuntos
Glioma/genética , Isocitrato Desidrogenase/genética , Convulsões/genética , Telomerase/genética , Neoplasias Encefálicas/patologia , Sistema Nervoso Central/patologia , Feminino , Glioma/classificação , Glioma/patologia , Glioma/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Gradação de Tumores , Convulsões/etiologia , Análise de Sequência de DNA/métodos
8.
Cell Physiol Biochem ; 48(4): 1755-1770, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30078018

RESUMO

BACKGROUND/AIMS: CDH18 (cadherin 18) is specifically expressed in the central nervous system and associated with various neuropsychiatric disorders. In this study, the role of CDH18 in glioma carcinogenesis and progression was investigated. METHODS: The expression of CDH18 and its prognostic value in patients with gliomas were analyzed in public database and validated by real-time PCR/immunohistochemical staining (IHC) in our cohort. CCK-8 assay, transwell migration assay, wound healing assay, clonogenic assay and tumorigenicity assay were used to compare the proliferation, invasion and migration ability of glioma cells with different expressions of CDH18. iTRAQ-based quantitative proteomic analysis were used to reveal the downstream target of CDH18. Rescue experiments were conducted to further validate the relationship between UQCRC2 and CDH18. RESULTS: The expression of CDH18 was depressed in a ladder-like pattern from normal tissues to WHO IV gliomas, and was an independent prognostic factor in TCGA (The Cancer Genome Atlas), CGGA (the Chinese glioma genome-atlas) and our glioma cohorts (n=453). Functional experiments in vitro and in vivo demonstrated that CDH18 inhibited invasion/migration, enhanced chemoresistance and suppressed tumorigenicity of glioma cells. UQCRC2 was identified as the downstream target of CDH18 by proteomic analysis. The expression of UQCRC2 was gradually absent as the WHO grades of gliomas escalated and was positively correlated with the expression of CDH18. Furthermore, in vitro assays demonstrated that down-regulation of UQCRC2 partly reversed the inhibition of invasion/migration ability and chemoresistance in CDH18 overexpressed glioma cell lines. Survival analysis demonstrated that combined CDH18/UQCRC2 biomarkers significantly influenced the prognosis of glioma patients. CONCLUSIONS: The present research demonstrated that CDH18 exerted its tumor-suppressor role via UQCRC2 in glioma cells and CDH18 might serve as a therapeutic target for treating gliomas.


Assuntos
Neoplasias Encefálicas/patologia , Caderinas/metabolismo , Complexo III da Cadeia de Transporte de Elétrons/metabolismo , Glioma/patologia , Idoso , Animais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/metabolismo , Caderinas/genética , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Dacarbazina/análogos & derivados , Dacarbazina/farmacologia , Resistencia a Medicamentos Antineoplásicos , Complexo III da Cadeia de Transporte de Elétrons/antagonistas & inibidores , Complexo III da Cadeia de Transporte de Elétrons/genética , Regulação Neoplásica da Expressão Gênica , Glioma/metabolismo , Humanos , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Proteínas Mitocondriais , Prognóstico , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Temozolomida
9.
Oncol Rep ; 38(5): 3078-3084, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28901497

RESUMO

A previous study revealed that ubiquitin-like with PHD and RING finger domains 1 (UHRF1) promoted cell proliferation and was a potential biomarker in medulloblastoma (MB). In the present study, we reported that miR-378 inhibited the expression of UHRF1 to affect the proliferation of MB through competitive binding to the same region of its 3'-UTR. We found that the expression of miR-378 was significantly downregulated in MB tissues and inversely correlated with the expression of UHRF1. Western blot analysis revealed that overexpression of miR-378 led to the suppression of UHRF1. Moreover, a dual-luciferase assay demonstrated that miR-378 negatively regulated the activity of target gene UHRF1 by binding to its 3'-UTR. An in vitro assay revealed that overexpression of miR-378 suppressed MB cell proliferation and promoted cell apoptosis. Ectopic expression of UHRF1 rescued miR-378-suppressed cell proliferation and miR-378-promoted cell apoptosis. Collectively, the present study demonstrated that miR-378 could inhibit the proliferation of MB by downregulation of UHRF1 and act as a potential therapeutic target against MB.


Assuntos
Proteínas Estimuladoras de Ligação a CCAAT/genética , Neoplasias Cerebelares/genética , Meduloblastoma/genética , MicroRNAs/genética , Regiões 3' não Traduzidas , Apoptose , Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Cerebelares/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Meduloblastoma/metabolismo , Ubiquitina-Proteína Ligases
10.
Oncotarget ; 8(70): 115657-115666, 2017 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-29383189

RESUMO

BACKGROUNDS: HOX (homologous box) is known as the dominant gene of vertebrate growth and cell differentiation. Abnormal expression of HOX gene in various tumors has attracted the attention of scholars. As a component of HOX clusters, HOXD4 plays a controversial role in the tumorigenesis of central nervous system. RESULTS: The data demonstrated that and the results demonstrated that HOXD4 was overexpressed in glioma tissues compared to that of normal brain tissues. patients with high HOXD4 expression had a significant shorter survival than those with low HOXD4 expression in total glioma cohort (p<0.001), WHO Grade II cohort (p=0.003) and Grade III cohort (p<0.001), but not in Grade IV cohort when OS (overall survival) was analyzed (p=0.216). The findings were confirmed by the large-scale omics data analysis including lower-grade glioma (LGG) and glioblastoma multiforme (GBM) in TCGA (the cancer genome atlas) and CGGA (Chinese glioma genome atlas). Moreover, it was revealed that the expression of HOXD4 have a significant impact on the OS of Grade IV glioma with IDH wild-type and 1p/19q intact according to TCGA data. METHODS: Clinicopathological analysis of HOXD4 expression in 453 glioma patients was performed in the current study. Expression of HOXD4 was evaluated by qPCR and immunohistochemical (IHC) staining. Univariate and multivariate analysis were conducted to investigate the prognostic role of HOXD4 in glioma patients. CONCLUSIONS: Expression of HOXD4 was closely related to the clinical outcomes of patients with gliomas, and HOXD4 may be a potential prognostic biomarker of gliomas.

11.
Nan Fang Yi Ke Da Xue Xue Bao ; 32(9): 1255-9, 2012 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-22985558

RESUMO

OBJECTIVE: To characterize the expressions of peroxiredoxin 1 (Prx1), peroxiredoxin 6 (Prx6) and glial fibrillary acidic protein (GFAP) in human brain astrocytoma and explore their clinical significance. METHODS: The protein and mRNA expression levels of Prx1, Prx6 and GFAP in human brain astrocytoma and normal brain tissue specimens were determined by Western blotting, RT-PCR and immunohistochemistry. RESULTS: The protein and mRNA expressions of Prx1 and Prx6 increased significantly in the order of normal brain tissue, grade II astrocytoma, grade III astrocytoma and grade IV astrocytoma (P<0.05). The protein and mRNA expressions of GFAP decreased significantly in grade III and IV astrocytoma compared with those in grade II astrocytoma and normal brain tissues (P<0.05). CONCLUSION: Prx1 and Prx6 may play important roles in the invasion and malignant development of human brain astrocytoma, and may serve as biomarkers for evaluating the invasiveness, malignancy and prognosis of the tumor as well as potential molecular targets in astrocytoma therapy.


Assuntos
Astrocitoma/metabolismo , Neoplasias Encefálicas/metabolismo , Proteína Glial Fibrilar Ácida/metabolismo , Peroxirredoxina VI/metabolismo , Peroxirredoxinas/metabolismo , Adolescente , Adulto , Idoso , Astrocitoma/patologia , Neoplasias Encefálicas/patologia , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
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