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1.
J Formos Med Assoc ; 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38866694

RESUMO

BACKGROUND: Spontaneous intracerebral hemorrhage (ICH) accounts for up to 20% of all strokes and results in 40% mortality at 30 days. Although conservative medical management is still the standard treatment for ICH patients with small hematoma, patients with residual hematoma ≤15 mL after surgery are associated with better functional outcomes and survival rates. This study reported our clinical experience with using Robotic Stereotactic Assistance (ROSA) as a safe and effective approach for stereotactic ICH aspiration and intra-clot catheter placement. METHODS: A retrospective analysis was conducted of patients with spontaneous ICH who underwent ROSA-guided ICH aspiration surgery. ROSA-guided ICH surgical techniques, an aspiration and intra-clot catheter placement protocol, and a specific operative workflow (pre-operative protocol, intraoperative procedure and postoperative management) were employed to aspirate ICH using the ROSA One Brain, and appropriate follow-up care was provided. RESULTS: From September 14, 2021 to May 4, 2022, a total of 7 patients were included in the study. Based on our workflow design, ROSA-guided stereotactic ICH aspiration effectively aspirated more than 50% of hematoma volume (or more than 30 mL for massive hematomas), thereby reducing the residual hematoma to less than 15 mL. The mean operative time of entire surgical procedure was 1.3 ± 0.3 h, with very little perioperative blood loss and no perioperative complications. No patients required catheter replacement and all patients' functional status improved. CONCLUSIONS: Within our clinical practice ROSA-guided ICH aspiration, using our established protocol and workflow, was safe and effective for reducing hematoma volume, with positive functional outcomes.

2.
Childs Nerv Syst ; 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38806857

RESUMO

PURPOSE: Pediatric hydrocephalus is the most common cause of surgically treatable neurological disease in children. Controversies exist whether endoscopic third ventriculostomy (ETV) or cerebrospinal fluid (CSF) shunt placement is the most appropriate treatment for pediatric hydrocephalus. This study aimed to compare the risk of re-operation and death between the two procedures. METHODS: We performed a retrospective population-based cohort study and included patients younger than 20-years-old who underwent CSF shunt or ETV for hydrocephalus from the Taiwan National Health Insurance Research Database. RESULTS: A total of 3,555 pediatric patients from 2004 to 2017 were selected, including 2,340 (65.8%) patients that received CSF shunt placement and 1215 (34.2%) patients that underwent ETV. The incidence of all-cause death was 3.31 per 100 person-year for CSF shunt group and 2.52 per 100 person-year for ETV group, with an adjusted hazard ratio (HR) of 0.79 (95% confidence interval [CI] = 0.66-0.94, p = 0.009). The cumulative incidence competing risk for reoperation was 31.2% for the CSF shunt group and 26.4% for the ETV group, with an adjusted subdistribution HR of 0.82 (95% CI = 0.70-0.96, p = 0.015). Subgroup analysis showed that ETV was beneficial for hydrocephalus coexisting with brain or spinal tumor, central nervous system infection, and intracranial hemorrhage. CONCLUSION: Our data indicates ETV is a better operative procedure for pediatric hydrocephalus when advanced surgical techniques and instruments are available.

3.
Sci Rep ; 14(1): 4011, 2024 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-38369533

RESUMO

The aim of the study was to investigate whether morphology (i.e. compact/diffuse) of brain arteriovenous malformations (bAVMs) correlates with the incidence of hemorrhagic events in patients receiving Stereotactic Radiosurgery (SRS) for unruptured bAVMs. This retrospective study included 262 adult patients with unruptured bAVMs who underwent upfront SRS. Hemorrhagic events were defined as evidence of blood on CT or MRI. The morphology of bAVMs was evaluated using automated segmentation which calculated the proportion of vessel, brain tissue, and cerebrospinal fluid in bAVMs on T2-weighted MRI. Compactness index, defined as the ratio of vessel to brain tissue, categorized bAVMs into compact and diffuse types based on the optimal cutoff. Cox proportional hazard model was used to identify the independent factors for post-SRS hemorrhage. The median clinical follow-ups was 62.1 months. Post-SRS hemorrhage occurred in 13 (5.0%) patients and one of them had two bleeds, resulting in an annual bleeding rate of 0.8%. Multivariable analysis revealed bAVM morphology (compact versus diffuse), bAVM volume, and prescribed margin dose were significant predictors. The post-SRS hemorrhage rate increased with larger bAVM volume only among the diffuse nidi (1.7 versus 14.9 versus 30.6 hemorrhage per 1000 person-years in bAVM volume < 20 cm3 versus 20-40 cm3 versus > 40 cm3; p = 0.022). The significantly higher post-SRS hemorrhage rate of Spetzler-Martin grade IV-V compared with grade I-III bAVMs (20.0 versus 3.3 hemorrhages per 1000 person-years; p = 0.001) mainly originated from the diffuse bAVMs rather than the compact subgroup (30.9 versus 4.8 hemorrhages per 1000 person-years; p = 0.035). Compact and smaller bAVMs, with higher prescribed margin dose harbor lower risks of post-SRS hemorrhage. The post-SRS hemorrhage rate exceeded 2.2% annually within the diffuse and large (> 40 cm3) bAVMs and the diffuse Spetzler-Martin IV-V bAVMs. These findings may help guide patient selection of SRS for the unruptured bAVMs.


Assuntos
Malformações Arteriovenosas Intracranianas , Radiocirurgia , Adulto , Humanos , Estudos Retrospectivos , Resultado do Tratamento , Radiocirurgia/efeitos adversos , Radiocirurgia/métodos , Encéfalo , Malformações Arteriovenosas Intracranianas/diagnóstico por imagem , Malformações Arteriovenosas Intracranianas/epidemiologia , Malformações Arteriovenosas Intracranianas/etiologia , Hemorragia/epidemiologia , Hemorragia/etiologia , Seguimentos
4.
Parkinsonism Relat Disord ; 111: 105431, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37164870

RESUMO

Magnetic resonance-guided focused ultrasound (MRgFUS) is a new surgical treatment for Parkinson's disease (PD). Previous experience with radiofrequency lesionectomy and deep brain stimulation (DBS) has identified several candidate targets for MRgFUS intended to alleviate the motor symptoms of PD. The main advantage of MRgFUS is that it is incisionless. MRgFUS has certain limitations and is associated with adverse effects. The present study reviews the literature on conventional surgical interventions for PD, discusses recent studies on MRgFUS, and the comparison between DBS and MRgFUS for PD. The reviews aims to provide an essential reference for neurologists to select the appropriate treatments for patients with PD.


Assuntos
Estimulação Encefálica Profunda , Tremor Essencial , Doença de Parkinson , Procedimentos Cirúrgicos Ultrassônicos , Humanos , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/cirurgia , Resultado do Tratamento , Tremor Essencial/terapia , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética
5.
Eur J Med Chem ; 248: 115054, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36630883

RESUMO

The pursuit of activating the HDAC inhibitory template towards additional mechanisms spurred us to design dual modulators (Sig-1R agonist - HDAC inhibitor) via utilization of the core structural unit of donepezil (an FDA-approved anti-Alzheimer's agent) as a surface recognition part. Literature precedents coupled with our experience rendered us with several insights that led to the inclusion of chemically diverse linkers and hydroxamic acid (zinc-binding motif) as the other components of HDAC inhibitory pharmacophore. With this envisionment and clarity, donepezil-based HDAC inhibitory adducts were furnished and exhaustively explored for their anti-GBM efficacy. Resultantly, a magnificently potent HDAC inhibitor 10 [IC50 (HDAC6) = 2.7 nM, IC50 (HDAC2) = 0.71 µM] was pinpointed that was endowed with the ability to: i) exert cell growth inhibitory effects against Human U87MG GBM cells ii) cause death in TMZ-resistant GBM cells iii) induce subG1 arrest in GBM cells iv) prolong the survival of TMZ-resistant U87MG inoculated orthotopic mice (in-vivo studies) v) induce GBM cell apoptosis via binding to Sig-1R. Collectively, the results led to the identification of compound 10 as a tractable anti-GBM agent that deserves detailed investigation for the accomplishment of its candidature as a GBM therapeutic.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Humanos , Animais , Camundongos , Donepezila/farmacologia , Inibidores de Histona Desacetilases/farmacologia , Inibidores de Histona Desacetilases/uso terapêutico , Linhagem Celular Tumoral , Neoplasias Encefálicas/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Ácidos Hidroxâmicos/farmacologia , Ácidos Hidroxâmicos/uso terapêutico , Proliferação de Células
6.
J Neurosurg ; 138(1): 241-250, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-35594883

RESUMO

OBJECTIVE: The goal of the study was to define and quantify brain arteriovenous malformation (bAVM) compactness and to assess its effect on outcomes after Gamma Knife radiosurgery (GKRS) for unruptured bAVMs. METHODS: Unsupervised machine learning with fuzzy c-means clustering was used to differentiate the tissue constituents of bAVMs on T2-weighted MR images. The percentages of vessel, brain, and CSF were quantified. The proposed compactness index, defined as the ratio of vasculature tissue to brain tissue, categorized bAVM morphology into compact, intermediate, and diffuse types according to the tertiles of this index. The outcomes of interest were complete obliteration and radiation-induced changes (RICs). RESULTS: A total of 209 unruptured bAVMs treated with GKRS were retrospectively included. The median imaging and clinical follow-up periods were 49.2 and 72.3 months, respectively. One hundred seventy-three bAVMs (82.8%) achieved complete obliteration after a median latency period of 43.3 months. The rates of RIC and permanent RIC were 76.1% and 3.8%, respectively. Post-GKRS hemorrhage occurred in 14 patients (6.7%), resulting in an annual bleeding risk of 1.0%. Compact bAVM, smaller bAVM volume, and exclusively superficial venous drainage were independent predictors of complete obliteration. Diffuse bAVM morphology, larger bAVM volume, and higher margin dose were independently associated with RICs. CONCLUSIONS: The compactness index quantitatively describes the compactness of unruptured bAVMs. Moreover, compact bAVMs may have a higher obliteration rate and a smaller risk of RICs than diffuse bAVMs. This finding could help guide decision-making regarding GKRS treatment for patients with unruptured bAVMs.


Assuntos
Malformações Arteriovenosas Intracranianas , Radiocirurgia , Humanos , Resultado do Tratamento , Seguimentos , Radiocirurgia/efeitos adversos , Radiocirurgia/métodos , Malformações Arteriovenosas Intracranianas/diagnóstico por imagem , Malformações Arteriovenosas Intracranianas/radioterapia , Malformações Arteriovenosas Intracranianas/etiologia , Estudos Retrospectivos , Encéfalo
7.
J Biomed Sci ; 29(1): 21, 2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-35337344

RESUMO

BACKGROUND: Sp1 is involved in the recurrence of glioblastoma (GBM) due to the acquirement of resistance to temozolomide (TMZ). Particularly, the role of Sp1 in metabolic reprogramming for drug resistance remains unknown. METHODS: RNA-Seq and mass spectrometry were used to analyze gene expression and metabolites amounts in paired GBM specimens (primary vs. recurrent) and in paired GBM cells (sensitive vs. resistant). ω-3/6 fatty acid and arachidonic acid (AA) metabolism in GBM patients were analyzed by targeted metabolome. Mitochondrial functions were determined by Seahorse XF Mito Stress Test, RNA-Seq, metabolome and substrate utilization for producing ATP. Therapeutic options targeting prostaglandin (PG) E2 in TMZ-resistant GBM were validated in vitro and in vivo. RESULTS: Among the metabolic pathways, Sp1 increased the prostaglandin-endoperoxide synthase 2 expression and PGE2 production in TMZ-resistant GBM. Mitochondrial genes and metabolites were obviously increased by PGE2, and these characteristics were required for developing resistance in GBM cells. For inducing TMZ resistance, PGE2 activated mitochondrial functions, including fatty acid ß-oxidation (FAO) and tricarboxylic acid (TCA) cycle progression, through PGE2 receptors, E-type prostanoid (EP)1 and EP3. Additionally, EP1 antagonist ONO-8713 inhibited the survival of TMZ-resistant GBM synergistically with TMZ. CONCLUSION: Sp1-regulated PGE2 production activates FAO and TCA cycle in mitochondria, through EP1 and EP3 receptors, resulting in TMZ resistance in GBM. These results will provide us a new strategy to attenuate drug resistance or to re-sensitize recurred GBM.


Assuntos
Glioblastoma , Apoptose/genética , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Ácidos Graxos/uso terapêutico , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Glioblastoma/metabolismo , Humanos , Mitocôndrias , Temozolomida/farmacologia
8.
Neurosurg Focus ; 52(1): E9, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34973679

RESUMO

OBJECTIVE: The use of robotics in spinal surgery has gained popularity because of its promising accuracy and safety. ROSA is a commonly used surgical robot system for spinal surgery. The aim of this study was to compare outcomes between robot-guided and freehand fluoroscopy-guided instrumentation in minimally invasive surgery (MIS)-transforaminal lumbar interbody fusion (TLIF). METHODS: This retrospective consecutive series reviewed 224 patients who underwent MIS-TLIF from March 2019 to April 2020 at a single institution. All patients were diagnosed with degenerative pathologies. Of those, 75 patients underwent robot-guided MIS-TLIF, and 149 patients underwent freehand fluoroscopy-guided MIS-TLIF. The incidences of pedicle breach, intraoperative outcomes, postoperative outcomes, and short-term pain control were compared. RESULTS: The patients who underwent robot-guided surgery had a lower incidence of pedicle breach (0.27% vs 1.75%, p = 0.04) and less operative blood loss (313.7 ± 214.1 mL vs 431.6 ± 529.8 mL, p = 0.019). Nonsignificant differences were observed in operative duration (280.7 ± 98.1 minutes vs 251.4 ± 112.0 minutes, p = 0.056), hospital stay (6.6 ± 3.4 days vs 7.3 ± 4.4 days, p = 0.19), complications (intraoperative, 1.3% vs 1.3%, p = 0.45; postoperative surgery-related, 4.0% vs 4.0%, p = 0.99), and short-term pain control (postoperative day 1, 2.1 ± 1.2 vs 1.8 ± 1.2, p = 0.144; postoperative day 30, 1.2 ± 0.5 vs 1.3 ± 0.7, p = 0.610). A shorter operative duration for 4-level spinal surgery was found in the robot-guided surgery group (388.7 ± 107.3 minutes vs 544.0 ± 128.5 minutes, p = 0.047). CONCLUSIONS: This retrospective review revealed that patients who underwent robot-guided MIS-TLIF experienced less operative blood loss. They also benefited from a shorter operative duration with higher-level (> 3 levels) spinal surgery. The postoperative outcomes were similar for both robot-guided and freehand fluoroscopy-guided procedures.


Assuntos
Robótica , Fusão Vertebral , Estudos de Casos e Controles , Fluoroscopia , Humanos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Estudos Retrospectivos , Fusão Vertebral/métodos , Resultado do Tratamento
9.
Cell Death Dis ; 12(10): 884, 2021 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-34584069

RESUMO

DNA repair promotes the progression and recurrence of glioblastoma (GBM). However, there remain no effective therapies for targeting the DNA damage response and repair (DDR) pathway in the clinical setting. Thus, we aimed to conduct a comprehensive analysis of DDR genes in GBM specimens to understand the molecular mechanisms underlying treatment resistance. Herein, transcriptomic analysis of 177 well-defined DDR genes was performed with normal and GBM specimens (n = 137) from The Cancer Genome Atlas and further integrated with the expression profiling of histone deacetylase 6 (HDAC6) inhibition in temozolomide (TMZ)-resistant GBM cells and patient-derived tumor cells. The effects of HDAC6 inhibition on DDR signaling were examined both in vitro and intracranial mouse models. We found that the expression of DDR genes, involved in repair pathways for DNA double-strand breaks, was upregulated in highly malignant primary and recurrent brain tumors, and their expression was related to abnormal clinical features. However, a potent HDAC6 inhibitor, MPT0B291, attenuated the expression of these genes, including RAD51 and CHEK1, and was more effective in blocking homologous recombination repair in GBM cells. Interestingly, it resulted in lower cytotoxicity in primary glial cells than other HDAC6 inhibitors. MPT0B291 reduced the growth of both TMZ-sensitive and TMZ-resistant tumor cells and prolonged survival in mouse models of GBM. We verified that HDAC6 regulated DDR genes by affecting Sp1 expression, which abolished MPT0B291-induced DNA damage. Our findings uncover a regulatory network among HDAC6, Sp1, and DDR genes for drug resistance and survival of GBM cells. Furthermore, MPT0B291 may serve as a potential lead compound for GBM therapy.


Assuntos
Dano ao DNA , Glioblastoma/enzimologia , Glioblastoma/patologia , Desacetilase 6 de Histona/metabolismo , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular , Dano ao DNA/genética , Reparo do DNA/efeitos dos fármacos , Reparo do DNA/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioblastoma/genética , Desacetilase 6 de Histona/antagonistas & inibidores , Humanos , Indóis , Masculino , Camundongos Endogâmicos NOD , Proteínas de Neoplasias/metabolismo , Neuroglia/metabolismo , Piridinas , Temozolomida/farmacologia
10.
Int J Mol Sci ; 22(11)2021 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-34074038

RESUMO

Glioblastoma multiforme (GBM) has remained one of the most lethal and challenging cancers to treat. Previous studies have shown encouraging results when irinotecan was used in combination with temozolomide (TMZ) for treating GBM. However, irinotecan has a narrow therapeutic index: a slight dose increase in irinotecan can induce toxicities that outweigh its therapeutic benefits. SN-38 is the active metabolite of irinotecan that accounts for both its anti-tumor efficacy and toxicity. In our previous paper, we showed that SN-38 embedded into 50:50 biodegradable poly[(d,l)-lactide-co-glycolide] (PLGA) microparticles (SMPs) provides an efficient delivery and sustained release of SN-38 from SMPs in the brain tissues of rats. These properties of SMPs give them potential for therapeutic application due to their high efficacy and low toxicity. In this study, we tested the anti-tumor activity of SMP-based interstitial chemotherapy combined with TMZ using TMZ-resistant human glioblastoma cell line-derived xenograft models. Our data suggest that treatment in which SMPs are combined with TMZ reduces tumor growth and extends survival in mice bearing xenograft tumors derived from both TMZ-resistant and TMZ-sensitive human glioblastoma cell lines. Our findings demonstrate that combining SMPs with TMZ may have potential as a promising strategy for the treatment of GBM.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Glioblastoma/tratamento farmacológico , Irinotecano/farmacologia , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Temozolomida/farmacologia , Animais , Apoptose/efeitos dos fármacos , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Glioblastoma/mortalidade , Glioblastoma/patologia , Humanos , Irinotecano/efeitos adversos , Camundongos , Microplásticos/química , Microscopia Eletrônica de Varredura , Ratos , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Eur J Med Chem ; 217: 113338, 2021 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-33744690

RESUMO

Hurdled and marred by the notorious nature of glioblastomas (GBM) in terms of resistance to therapy and limited drug delivery into the brain, the anti-GBM drug pipeline is required to be loaded with mechanistically diverse agents. The consideration of HDAC inhibition as a prudent approach to circumvent the resistance issue in GBM spurred us to pragmatically design and synthesizes hydroxamic acids endowed with CNS penetrating ability. By virtue of the blood brain barrier permeability (BBB), memantine was envisioned as an appropriate CAP component for the construction of the HDAC inhibitors. Diverse linkers were stapled for the tetheration of the zinc binding motif with the CAP group to pinpoint an appropriate combination (CAP and linker) that could confer inhibitory preference to HDAC6 isoform (overexpressed in GBM). Resultantly, hydroxamic acid 16 was identified as a promising compound that elicited striking antiproliferative effects against Human U87MG GBM cells as well as TMZ-resistant GBM cells and P1S cells, a concurrent chemo radiotherapy (CCRT)-resistant/patient-derived glioma cell line mediated through preferential HDAC6 inhibition (IC50 = 5.42 nM). Furthermore, 16 exerted cell cycle arrest at G2 phase, induced apoptosis in GBM cells at high concentration and exhibited high BBB permeability. To add on, in-vivo study revealed that the administration of compound 16 prolonged the survival of TMZ-resistant U87MG inoculated orthotopic mice. Overall, the cumulative results indicate that 16 is a tractable CNS penetrant preferential HDAC6 inhibitor that might emerge as a potent weapon against GBM.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Desenho de Fármacos , Glioblastoma/tratamento farmacológico , Desacetilase 6 de Histona/antagonistas & inibidores , Inibidores de Histona Desacetilases/farmacologia , Memantina/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Glioblastoma/metabolismo , Glioblastoma/patologia , Desacetilase 6 de Histona/metabolismo , Inibidores de Histona Desacetilases/síntese química , Inibidores de Histona Desacetilases/química , Humanos , Masculino , Memantina/síntese química , Memantina/química , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Simulação de Acoplamento Molecular , Estrutura Molecular , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Relação Estrutura-Atividade , Células Tumorais Cultivadas
12.
Biochem Biophys Res Commun ; 550: 113-119, 2021 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-33691197

RESUMO

B-cell-specific Moloney murine leukemia virus integration site 1 (BMI1) appears to be essential for promoting certain types of cancer, and its inhibition effectively reduced the stemness of cancer cells. Therefore, this study aimed to investigate the potential role of BMI1 in glioma. To this end, we first investigated BMI1 expression in brain tumors using microarray datasets in ONCOMINE, which indicated that BMI1 levels were not commonly increased in clinical brain tumors. Moreover, survival plots in PROGgeneV2 also showed that BMI1 expression was not significantly associated with reduced survival in glioma patients. Interestingly, stressful serum deprivation and anchorage independence growth conditions led to an increased BMI1 expression in glioma cells. A stress-responsive pathway, HDAC/Sp1, was further identified to regulate BMI1 expression. The HDAC inhibitor vorinostat (SAHA) prevented Sp1 binding to the BMI1 promoter, leading to a decreased expression of BMI1 and attenuating tumor growth of TMZ-resistant glioma xenografts. Importantly, we further performed survival analysis using PROGgeneV2 and found that an elevated expression of HDAC1,3/Sp1/BMI1 but not BMI1 alone showed an increased risk of death in both high- and low-grade glioma patients. Thus, HDAC-mediated Sp1 deacetylation is critical for BMI1 regulation to attenuate stress- and therapy-induced death in glioma cells, and the HDAC/Sp1 axis is more important than BMI1 and appears as a therapeutic target to prevent recurrence of malignant glioma cells persisting after primary therapy.


Assuntos
Biomarcadores Tumorais/metabolismo , Glioma/diagnóstico , Glioma/metabolismo , Células-Tronco Neoplásicas/metabolismo , Complexo Repressor Polycomb 1/metabolismo , Animais , Linhagem Celular , Regulação Neoplásica da Expressão Gênica , Glioma/patologia , Histona Desacetilase 1/metabolismo , Histona Desacetilases/metabolismo , Humanos , Masculino , Camundongos , Prognóstico , Regiões Promotoras Genéticas/genética , Fator de Transcrição Sp1/metabolismo , Regulação para Cima
13.
Cancers (Basel) ; 12(4)2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32326583

RESUMO

Patients with glioblastoma are at high risk of local recurrences after initial treatment with standard therapy, and recurrent tumor cells appear to be resistant to first-line drug temozolomide. Thus, finding an effective second-line agent for treating primary and recurrent glioblastomas is critical. Betulinic acid (BA), a natural product of plant origin, can cross the blood-brain barrier. Here, we investigated the antitumor effects of BA on typical glioblastoma cell lines and primary glioblastoma cells from patients, as well as corresponding temozolomide-resistant cells. Our findings verified that BA significantly reduced growth in all examined cells. Furthermore, gene-expression array analysis showed that the unfolded-protein response was significantly affected by BA. Moreover, BA treatment increased activation of the protein kinase RNA-like endoplasmic reticulum kinase (PERK)/C/EBP homologous protein (CHOP) apoptotic pathway, and reduced specificity protein 1 (Sp1) expression. However, Sp1 overexpression reversed the observed cell-growth inhibition and PERK/CHOP signaling activation induced by BA. Because temozolomide-resistant cells exhibited significantly increased Sp1 expression, we concluded that Sp1-mediated PERK/CHOP signaling inhibition protects glioblastoma against cancer therapies; hence, BA treatment targeting this pathway can be considered as an effective therapeutic strategy to overcome such chemoresistance and tumor relapse.

14.
J Cell Sci ; 133(9)2020 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-32253322

RESUMO

Microtubules (MTs) are the most abundant cytoskeleton in neurons, and control multiple facets of their development. While the MT-organizing center (MTOC) in mitotic cells is typically located at the centrosome, the MTOC in neurons switches to non-centrosomal sites. A handful of cellular components have been shown to promote non-centrosomal MT (ncMT) formation in neurons, yet the regulation mechanism remains unknown. Here, we demonstrate that the small GTPase Ran is a key regulator of ncMTs in neurons. Using an optogenetic tool that enables light-induced local production of RanGTP, we demonstrate that RanGTP promotes ncMT plus-end growth along the neurite. Additionally, we discovered that actin waves drive the anterograde transport of RanGTP. Pharmacological disruption of actin waves abolishes the enrichment of RanGTP and reduces growing ncMT plus-ends at the neurite tip. These observations identify a novel regulation mechanism for ncMTs and pinpoint an indirect connection between the actin and MT cytoskeletons in neurons.


Assuntos
Actinas , Neuritos , Actinas/genética , Centrossomo , Microtúbulos , Neurônios
15.
J Biomed Sci ; 26(1): 77, 2019 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-31629402

RESUMO

BACKGROUND: Intratumor subsets with tumor-initiating features in glioblastoma are likely to survive treatment. Our goal is to identify the key factor in the process by which cells develop temozolomide (TMZ) resistance. METHODS: Resistant cell lines derived from U87MG and A172 were established through long-term co-incubation of TMZ. Primary tumors obtained from patients were maintained as patient-derived xenograft for studies of tumor-initating cell (TIC) features. The cell manifestations were assessed in the gene modulated cells for relevance to drug resistance. RESULTS: Among the mitochondria-related genes in the gene expression databases, superoxide dismutase 2 (SOD2) was a significant factor in resistance and patient survival. SOD2 in the resistant cells functionally determined the cell fate by limiting TMZ-stimulated superoxide reaction and cleavage of caspase-3. Genetic inhibition of the protein led to retrieval of drug effect in mouse study. SOD2 was also associated with the TIC features, which enriched in the resistant cells. The CD133+ specific subsets in the resistant cells exhibited superior superoxide regulation and the SOD2-related caspase-3 reaction. Experiments applying SOD2 modulation showed a positive correlation between the TIC features and the protein expression. Finally, co-treatment with TMZ and the SOD inhibitor sodium diethyldithiocarbamate trihydrate in xenograft mouse models with the TMZ-resistant primary tumor resulted in lower tumor proliferation, longer survival, and less CD133, Bmi-1, and SOD2 expression. CONCLUSION: SOD2 plays crucial roles in the tumor-initiating features that are related to TMZ resistance. Inhibition of the protein is a potential therapeutic strategy that can be used to enhance the effects of chemotherapy.


Assuntos
Antineoplásicos Alquilantes/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Glioblastoma/tratamento farmacológico , Células-Tronco Neoplásicas/efeitos dos fármacos , Superóxido Dismutase/administração & dosagem , Temozolomida/farmacologia , Animais , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Xenoenxertos/fisiopatologia , Humanos , Camundongos , Células-Tronco Neoplásicas/fisiologia
16.
Cancers (Basel) ; 11(9)2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31527549

RESUMO

Cytochrome P450 (CYP) 17A1 is an important steroidogenic enzyme harboring 17α-hydroxylase and performing 17,20 lyase activities in multiple steps of steroid hormone synthesis, including dehydroepiandrosterone (DHEA) biosynthesis. Previously, we showed that CYP17A1-mediated DHEA production clearly protects glioblastomas from temozolomide-induced apoptosis, leading to drug resistance. Herein, we attempt to clarify whether the inhibition of CYP17A1 has a tumor-suppressive effect, and to determine the steroidogenesis-independent functions of CYP17A1 in glioblastomas. Abiraterone, an inhibitor of CYP17A1, significantly inhibits the proliferation of A172, T98G, and PT#3 (the primary glioblastoma cells) by inducing apoptosis. In parallel, abiraterone potently suppresses tumor growth in mouse models through transplantation of PT#3 cells to the back or to the brain. Based on evidence that abiraterone induces endoplasmic reticulum (ER) stress, followed by the accumulation of reactive oxygen species (ROS), CYP17A1 is important for ER health and redox homeostasis. To confirm our hypothesis, we showed that CYP17A1 overexpression prevents the initiation of ER stress and attenuates ROS production by regulating SAR1a/b expression. Abiraterone dissociates SAR1a/b from ER-localized CYP17A1, and induces SAR1a/b ubiquitination, leading to degradation. Furthermore, SAR1 overexpression rescues abiraterone-induced apoptosis and impairs redox homeostasis. In addition to steroid hormone synthesis, CYP17A1 associates with SAR1a/b to regulate protein processing and maintain ER health in glioblastomas.

17.
Mol Oncol ; 12(5): 756-771, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29603594

RESUMO

Glioblastoma multiforme (GBM) is a highly malignant type of brain tumor found in humans. GBM cells reproduce quickly, and the median survival time for patients after therapy is approximately 1 year with a high relapse rate. Current therapies and diagnostic tools for GBM are limited; therefore, we searched for a more favorable therapeutic target or marker protein for both therapy and diagnosis. We used mass spectrometry (MS) analysis to identify GBM-associated marker proteins from human plasma and GBM cell cultures. Additional plasma and 52 brain tissues obtained from patients with gliomas were used to validate the association rate of serum amyloid A1 (SAA1) in different grades of gliomas and its distribution in tumors. Microarray database analysis further validated the coefficient of SAA1 levels in gliomas. The cellular mechanisms of SAA1 in GBM proliferation and infiltration were investigated in vitro. We analyzed the correlation between SAA1 and patients' medication requirement to demonstrate the clinical effects of SAA1 in GBM. SAA1 was identified from MS analysis, and its level was revealed to be correlated with the disease grade, clinical severity, and survival rate of patients with gliomas. In vitro cultures, including GBM cells and normal astrocytes, revealed that SAA1 promotes cell migration and invasion through integrin αVß3 to activate the Erk signaling pathway. Magnetic resonance imaging and tumor region-specific microarray analysis identified a correlation between SAA1 and GBM cell infiltration in patients. In summary, our results demonstrate that SAA1 in combination with integrin αV and ß3 can serve as an indicator of high glioblastoma risk. We also identified the cellular mechanisms of SAA1 contributing to GBM progression, which can serve as the basis for future GBM therapy.


Assuntos
Movimento Celular , Progressão da Doença , Glioblastoma/metabolismo , Glioblastoma/patologia , Integrina alfaVbeta3/metabolismo , Proteína Amiloide A Sérica/metabolismo , Astrócitos/metabolismo , Linhagem Celular Tumoral , Permeabilidade da Membrana Celular , Feminino , Glioblastoma/sangue , Glioblastoma/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Análise de Sobrevida
18.
J Appl Clin Med Phys ; 18(6): 114-122, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28960724

RESUMO

In Gamma Knife forward treatment planning, normalization effect may be observed when multiple shots are used for treating large lesions. This effect can reduce the proportion of coverage of high-value isodose lines within targets. The aim of this study was to evaluate the performance of forward treatment planning techniques using the Leksell Gamma Knife for the normalization effect reduction. We adjusted the shot positions and weightings to optimize the dose distribution and reduce the overlap of high-value isodose lines from each shot, thereby mitigating the normalization effect during treatment planning. The new collimation system, Leksell Gamma Knife Perfexion, which contains eight movable sectors, provides an additional means to reduce the normalization effect by using composite shots. We propose different techniques in forward treatment planning that can reduce the normalization effect. Reducing the normalization effect increases the coverage proportion of higher isodose lines within targets, making the high-dose region within targets more uniform and increasing the mean dose to targets. Because of the increase in the mean dose to the target after reducing the normalization effect, we can set the prescribed marginal dose at a higher isodose level and reduce the maximum dose, thereby lowering the risk of complications.


Assuntos
Neoplasias Encefálicas/cirurgia , Neuroma Acústico/cirurgia , Planejamento de Assistência ao Paciente/normas , Radiocirurgia/normas , Planejamento da Radioterapia Assistida por Computador/métodos , Adulto , Algoritmos , Tronco Encefálico/efeitos da radiação , Humanos , Masculino , Pessoa de Meia-Idade , Radiometria/métodos , Dosagem Radioterapêutica , Radioterapia de Intensidade Modulada/métodos
19.
Pract Radiat Oncol ; 7(4): 221-227, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28336479

RESUMO

PURPOSE: Stereotactic radiosurgery (SRS) provides a noninvasive treatment modality for patients with medically refractory trigeminal neuralgia. The root entry zone (REZ) has been proposed to be an ideal stereotactic target because it is partially composed of centrally produced myelin, conferring a theoretical increased sensitivity to irradiation as well as increased susceptibility to neurovascular conflict, making it the site in which nociceptive signals likely arise. The aim of this study is to determine if there is a statistically and clinically significant difference in pain relief or facial hypesthesia following SRS based on distance of the stereotactic isocenter from REZ. METHODS AND MATERIALS: Patients undergoing Novalis radiosurgery for the treatment of trigeminal neuralgia with at least 3 months' follow-up were included in this study. Postoperative outcomes were stratified by Barrow Neurological Institute (BNI) score for pain relief and BNI facial numbness score for facial hypesthesia. RESULTS: Sixty-seven patients met inclusion criteria and were included in this study. BNI score of I-IIIa was attained in 82% of patients at 3 months and 65% at 1 year following SRS. Distance from isocenter to REZ varied from 0 to 8.6 mm, with a mean of 1.94 ± 1.62 mm. Logistic regression of target-REZ distance against pain relief outcome (patients with score I-IIIa and IIIb-V) was insignificant at 3 months (P = .988), 6 months (P = .925), 9 months (P = .845), and 12 months (P = .547) postoperatively. Furthermore, no significant correlation was found with logistic regression of target-REZ distance with pain relief outcome (patients with score I and score II-IV) (P = .544). CONCLUSIONS: The current analysis suggests that distance from REZ does not correlate with degree of postoperative pain relief or facial hypesthesia; thus, targeting specific regions within the trigeminal nerve in relation to these anatomical characteristics may not afford any advantage from this perspective.


Assuntos
Radiocirurgia/métodos , Neuralgia do Trigêmeo/cirurgia , Idoso , Feminino , Humanos , Masculino , Neuralgia do Trigêmeo/terapia
20.
Biomed Res Int ; 2015: 168384, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25629037

RESUMO

Degenerative diseases of the lumbar spine, which are common among elderly people, cause back pain and radicular symptoms and lead to a poor quality of life. Lumbar spinal fusion is a standardized and widely accepted surgical procedure used for treating degenerative lumbar diseases; however, the classical posterior approach used in this procedure is recognized to cause vascular and neurologic damage of the lumbar muscles. Various studies have suggested that using the minimally invasive transforaminal interbody fusion (TLIF) technique provides long-term clinical outcomes comparable to those of open TLIF approaches in selected patients. In this study, we compared the perioperative and short-term advantages of miniopen, MI, and open TLIF. Compared with open TLIF, MI-TLIF and miniopen TLIF were associated with less blood loss, shorter hospital stays, and longer operative times; however, following the use of these procedures, no difference in quality of life was measured at 6 months or 1 year. Whether miniopen TLIF or MI-TLIF can replace traditional TLIF as the surgery of choice for treating degenerative lumbar deformity remains unclear, and additional studies are required for validating the safety and efficiency of these procedures.


Assuntos
Vértebras Lombares/cirurgia , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Doenças da Coluna Vertebral/cirurgia , Fusão Vertebral/métodos , Humanos , Pessoa de Meia-Idade , Cuidados Pós-Operatórios , Complicações Pós-Operatórias/etiologia , Fusão Vertebral/efeitos adversos
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