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1.
Neurosurg Rev ; 45(4): 2615-2638, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35513737

RESUMO

Despite advances in cerebrospinal fluid shunting technology, complications remain a significant concern. There are some contradictions about the effectiveness of proximal catheter entry sites that decrease shunt failures. We aim to compare efficiency of shunts with ventricular frontal, ventricular occipital, and cisterna magna entry sites. The systemic search was conducted in the database from conception to February 16, 2022 following guidelines of PRISMA. Between 2860 identified articles, 24 articles including 6094 patients were used for data synthesis. The aggregated results of all patients showed that "overall shunt failure rate per year" in mixed hydrocephalus with ventricular frontal and occipital shunts, and cisterna magna shunt (CMS) were 9.0%, 12.6%, and 30.7%, respectively. The corresponding values for "shunt failure rate" due to obstruction were 15.3%, 31.5%, and 10.2%, respectively. The similar results for "shunt failure rate" due to infection were 11.3%, 9.1%, and 27.2%, respectively. The related values for "shunt failure rate" due to overdrainage were 2.9%, 3.9%, and 13.6%, respectively. CMS was successful in the immediate resolution of clinical symptoms. Shunting through an occipital entry site had a greater likelihood of inaccurate catheter placement and location. Contrary to possible shunt failure due to overdrainage, the failure likelihood due to obstruction and infection in pediatric patients was higher than that of mixed hydrocephalus patients. In both mixed and pediatric hydrocephalus, obstruction and overdrainage were the most and least common complications of ventricular frontal and occipital shunts, respectively. The most and least common complications of mixed CMS were infection and obstruction, respectively.


Assuntos
Cisterna Magna , Hidrocefalia , Derivações do Líquido Cefalorraquidiano/efeitos adversos , Criança , Falha de Equipamento , Humanos , Hidrocefalia/etiologia , Hidrocefalia/cirurgia , Procedimentos Neurocirúrgicos/efeitos adversos
2.
BMC Biol ; 18(1): 32, 2020 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-32209106

RESUMO

BACKGROUND: Nuclear factor-κB (NF-κB) plays a prominent role in promoting inflammation and resistance to DNA damaging therapy. We searched for proteins that modulate the NF-κB response as a prerequisite to identifying novel factors that affect sensitivity to DNA damaging chemotherapy. RESULTS: Using streptavidin-agarose pull-down, we identified the DExD/H-box RNA helicase, DDX39B, as a factor that differentially interacts with κB DNA probes. Subsequently, using both RNA interference and CRISPR/Cas9 technology, we demonstrated that DDX39B inhibits NF-κB activity by a general mechanism involving inhibition of p65 phosphorylation. Mechanistically, DDX39B mediates this effect by interacting with the pattern recognition receptor (PRR), LGP2, a pathway that required the cellular response to cytoplasmic double-stranded RNA (dsRNA). From a functional standpoint, loss of DDX39B promoted resistance to alkylating chemotherapy in glioblastoma cells. Further examination of DDX39B demonstrated that its protein abundance was regulated by site-specific sumoylation that promoted its poly-ubiquitination and degradation. These post-translational modifications required the presence of the SUMO E3 ligase, PIASx-ß. Finally, genome-wide analysis demonstrated that despite the link to the PRR system, DDX39B did not generally inhibit interferon-stimulated gene expression, but rather acted to attenuate expression of factors associated with the extracellular matrix, cellular migration, and angiogenesis. CONCLUSIONS: These results identify DDX39B, a factor with known functions in mRNA splicing and nuclear export, as an RNA-binding protein that blocks a subset of the inflammatory response. While these findings identify a pathway by which DDX39B promotes sensitization to DNA damaging therapy, the data also reveal a mechanism by which this helicase may act to mitigate autoimmune disease.


Assuntos
RNA Helicases DEAD-box/genética , NF-kappa B/metabolismo , Receptores de Reconhecimento de Padrão/genética , Transdução de Sinais , Alquilação , Animais , RNA Helicases DEAD-box/metabolismo , Sondas de DNA , Tratamento Farmacológico , Humanos , Camundongos , Receptores de Reconhecimento de Padrão/metabolismo
3.
J Stroke Cerebrovasc Dis ; 30(9): 105996, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34303090

RESUMO

OBJECTIVE: We hypothesize that procedure deployment rates and technical performance with minimally invasive surgery and thrombolysis for intracerebral hemorrhage (ICH) evacuation (MISTIE) can be enhanced in post-trial clinical practice, per Phase III trial results and lessons learned. MATERIALS AND METHODS: We identified ICH patients and those who underwent MISTIE procedure between 2017-2021 at a single site, after completed enrollments in the Phase III trial. Deployment rates, complications and technical outcomes were compared to those observed in the trial. Initial and final hematoma volume were compared between site measurements using ABC/2, MISTIE trial reading center utilizing manual segmentation, and a novel Artificial Intelligence (AI) based volume assessment. RESULTS: Nineteen of 286 patients were eligible for MISTIE. All 19 received the procedure (6.6% enrollment to screening rate 6.6% compared to 1.6% at our center in the trial; p=0.0018). Sixteen patients (84%) achieved evaculation target < 15 mL residual ICH or > 70% removal, compared to 59.7% in the trial surgical cohort (p=0.034). No poor catheter placement occurred and no surgical protocol deviations. Limitations of ICH volume assessments using the ABC/2 method were shown, while AI based methodology of ICH volume assessments had excellent correlation with manual segmentation by experienced reading centers. CONCLUSIONS: Greater procedure deployment and higher technical success rates can be achieved in post-trial clinical practice than in the MISTIE III trial. AI based measurements can be deployed to enhance clinician estimated ICH volume. Clinical outcome implications of this enhanced technical performance cannot be surmised, and will need assessment in future trials.


Assuntos
Hemorragia Cerebral/terapia , Procedimentos Neurocirúrgicos , Terapia Trombolítica , Adulto , Idoso , Idoso de 80 Anos ou mais , Inteligência Artificial , Hemorragia Cerebral/diagnóstico por imagem , Ensaios Clínicos Fase III como Assunto , Bases de Dados Factuais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos/efeitos adversos , Valor Preditivo dos Testes , Interpretação de Imagem Radiográfica Assistida por Computador , Estudos Retrospectivos , Terapia Trombolítica/efeitos adversos , Fatores de Tempo , Tomografia Computadorizada por Raios X , Resultado do Tratamento
4.
Mol Cell ; 44(5): 785-96, 2011 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-22152481

RESUMO

The functional significance of the signaling pathway induced by O(6)-methylguanine (O(6)-MeG) lesions is poorly understood. Here, we identify the p50 subunit of NF-κB as a central target in the response to O(6)-MeG and demonstrate that p50 is required for S(N)1-methylator-induced cytotoxicity. In response to S(N)1-methylation, p50 facilitates the inhibition of NF-κB-regulated antiapoptotic gene expression. Inhibition of NF-κB activity is noted to be an S phase-specific phenomenon that requires the formation of O(6)-MeG:T mismatches. Chk1 associates with p50 following S(N)1-methylation, and phosphorylation of p50 by Chk1 results in the inhibition of NF-κB DNA binding. Expression of an unphosphorylatable p50 mutant blocks inhibition of NF-κB-regulated antiapoptotic gene expression and attenuates S(N)1-methylator-induced cytotoxicity. While O(6)-MeG:T-induced, p50-dependent signaling is not sufficient to induce cell death, this pathway sensitizes cells to the cytotoxic effects of DNA breaks.


Assuntos
Dano ao DNA , Metilação de DNA , Subunidade p50 de NF-kappa B/metabolismo , Animais , Morte Celular , Linhagem Celular Tumoral , Humanos , Camundongos , Subunidade p50 de NF-kappa B/antagonistas & inibidores , Subunidade p50 de NF-kappa B/deficiência
5.
Nucleic Acids Res ; 41(2): 764-74, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23180782

RESUMO

Phosphorylation of the NF-κB subunit, p50, is necessary for cytotoxicity in response to DNA methylation damage. Here, we demonstrate that serine 329 phosphorylation regulates the interaction of p50 with specific NF-κB binding elements based on the identity of a single κB-site nucleotide. Specifically, S329 phosphorylation reduces the affinity of p50 for κB-sites that have a cytosine (C) at the -1 position without affecting binding to sequences with a -1 adenine. The differential interaction between phospho-p50 and the -1 base regulates the downstream transcriptional response and underlies the inhibition of anti-apoptotic gene expression following DNA damage. In genes with multiple κB-sites, the presence of a single -1C κB-site enables inhibition of NF-κB-dependent activity. The data suggest that interaction between phospho-p50 and the -1 κB nucleotide facilitates cytotoxicity in response to DNA damage. Moreover, although conservation of the entire κB-site sequence is not seen across species, the identity of the -1 nt in critical anti-apoptotic genes is conserved such that the overall response to DNA damage is maintained.


Assuntos
Dano ao DNA , Subunidade p50 de NF-kappa B/metabolismo , NF-kappa B/metabolismo , Animais , Sítios de Ligação , Linhagem Celular , DNA/química , DNA/metabolismo , Regulação da Expressão Gênica , Camundongos , Subunidade p50 de NF-kappa B/química , Nucleotídeos/metabolismo , Fosforilação , Regiões Promotoras Genéticas , Ligação Proteica , Serina/metabolismo , Transcrição Gênica
6.
Nanomedicine ; 10(1): 149-57, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23891990

RESUMO

A major obstacle to the management of malignant glioma is the inability to effectively deliver therapeutic agent to the tumor. In this study, we describe a polymeric nanoparticle vector that not only delivers viable therapeutic, but can also be tracked in vivo using MRI. Nanoparticles, produced by a non-emulsion technique, were fabricated to carry iron oxide within the shell and the chemotherapeutic agent, temozolomide (TMZ), as the payload. Nanoparticle properties were characterized and subsequently their endocytosis-mediated uptake by glioma cells was demonstrated. Convection-enhanced delivery (CED) can disperse nanoparticles through the rodent brain and their distribution is accurately visualized by MRI. Infusion of nanoparticles does not result in observable animal toxicity relative to control. CED of TMZ-bearing nanoparticles prolongs the survival of animals with intracranial xenografts compared to control. In conclusion, the described nanoparticle vector represents a unique multifunctional platform that can be used for image-guided treatment of malignant glioma. FROM THE CLINICAL EDITOR: GBM remains one of the most notoriously treatment-unresponsive cancer types. In this study, a multifunctional nanoparticle-based temozolomide delivery system was demonstrated to possess enhanced treatment efficacy in a rodent xenograft GBM model, with the added benefit of MRI-based tracking via the incorporation of iron oxide as a T2* contrast material in the nanoparticles.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Dacarbazina/análogos & derivados , Sistemas de Liberação de Medicamentos , Glioma/tratamento farmacológico , Nanopartículas/química , Animais , Neoplasias Encefálicas/diagnóstico por imagem , Linhagem Celular Tumoral , Convecção , Dacarbazina/administração & dosagem , Dacarbazina/química , Compostos Férricos/química , Glioma/diagnóstico por imagem , Glioma/patologia , Humanos , Imageamento por Ressonância Magnética , Camundongos , Nanopartículas/uso terapêutico , Polímeros/química , Polímeros/uso terapêutico , Radiografia , Ratos , Temozolomida , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Neurooncol Adv ; 6(1): vdae014, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38420615

RESUMO

Background: A significant unmet need exists for the treatment of glioblastoma, IDH-wildtype (GBM). Preclinical work shows that acetazolamide sensitizes GBM to temozolomide (TMZ) by overcoming TMZ resistance due to BCL-3-dependent upregulation of carbonic anhydrase. Acetazolamide is Food and Drug Administration-approved for the treatment of altitude sickness. Drug repurposing enables the application of drugs to diseases beyond initial indications. This multi-institutional, open-label, phase I trial examined a combination of acetazolamide and TMZ in patients with MGMT promoter-methylated high-grade glioma. Methods: A total of 24 patients (GBM, IDH-wildtype = 22; Grade 4 astrocytoma, IDH-mutant = 1; Grade 3 astrocytoma, IDH-mutant = 1) were accrued over 17 months. All patients received oral acetazolamide (250 mg BID for 7 days increased to 500 mg BID for Days 8-21 of each 28-day cycle) during the adjuvant phase of TMZ for up to 6 cycles. Results: No patient had a dose-limiting toxicity. Adverse events were consistent with known sequelae of acetazolamide and TMZ. In the 23 WHO Grade 4 patients, the median overall survival (OS) was 30.1 months and the median progression-free survival was 16.0 months. The 2-year OS was 60.9%. In total 37% of the study population had high BCL-3 staining and trended toward shorter OS (17.2 months vs N.R., P = .06). Conclusions: The addition of acetazolamide is safe and tolerable in GBM patients receiving standard TMZ. Survival results compare favorably to historical data from randomized trials in patients with MGMT promoter-methylated GBM and support examination of acetazolamide in a randomized trial. BCL-3 expression is a potential biomarker for prognosis in GBM or for patients more likely to benefit from TMZ.

8.
Cell Host Microbe ; 32(10): 1805-1821.e10, 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39293437

RESUMO

Microbiota and feeding modes influence the susceptibility of premature newborns to necrotizing enterocolitis (NEC) through mechanisms that remain unknown. Here, we show that microbiota colonization facilitated by breastmilk feeding promotes NOD-like receptor family CARD domain containing 5 (Nlrc5) gene expression in mouse intestinal epithelial cells (IECs). Notably, inducible knockout of the Nlrc5 gene in IECs predisposes neonatal mice to NEC-like injury in the small intestine upon viral inflammation in an NK1.1+ cell-dependent manner. By contrast, formula feeding enhances neonatal gut colonization with environment-derived tilivalline-producing Klebsiella spp. Remarkably, tilivalline disrupts microbiota-activated STAT1 signaling that controls Nlrc5 gene expression in IECs through a PPAR-γ-mediated mechanism. Consequently, this dysregulation hinders the resistance of neonatal intestinal epithelium to self-NK1.1+ cell cytotoxicity upon virus infection/colonization, promoting NEC development. Together, we discover the underappreciated role of intestinal microbiota colonization in shaping a disease tolerance program to viral inflammation and elucidate the mechanisms impacting NEC development in neonates.


Assuntos
Animais Recém-Nascidos , Enterocolite Necrosante , Microbioma Gastrointestinal , Mucosa Intestinal , Fator de Transcrição STAT1 , Animais , Enterocolite Necrosante/microbiologia , Enterocolite Necrosante/imunologia , Enterocolite Necrosante/virologia , Fator de Transcrição STAT1/metabolismo , Camundongos , Mucosa Intestinal/microbiologia , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Camundongos Knockout , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Transdução de Sinais , Células Epiteliais/microbiologia , Células Epiteliais/virologia , Células Epiteliais/imunologia , Humanos , Camundongos Endogâmicos C57BL
9.
Nanomaterials (Basel) ; 13(3)2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36770434

RESUMO

The present study aims to use enhanced ionic polymer-metal composites (IPMC) as an artificial muscle (a soft-active actuator) to restore eyelid movement of patients with ptosis. The previous eyelid movement mechanisms contained drawbacks, specifically in the lower eyelid. We used finite element analysis (FEA) to find the optimal mechanism among two different models (A and B). In addition to common electrodes of IPMC (gold and platinum), the bovine serum albumin (BSA) and microcrystalline cellulose (MCC) polymers, with optimal weight percentages of carbon nanotube (CNT) nanofiller, were also utilized as non-metallic electrodes to improve the efficiency of the IPMC actuator. In both models, IPMC with nanocomposite electrodes had higher efficiency as compared to the metallic electrodes. In model A, which moved eyelids indirectly, IPMC with MCC-CNT electrode generated a higher force (25.4%) and less stress (5.9 times) as compared to IPMC with BSA-CNT electrode. However, the use of model A (even with IPMCs) with nanocomposite electrodes can have limitations such as possible malposition issues in the eyelids (especially lower). IPMC with MCC-CNT nanocomposite electrode under model B, which moved eyelids directly, was the most efficient option to restore eyelid movement. It led to higher displacements and lower mechanical stress damage as compared to the BSA-CNT. This finding may provide surgeons with valuable data to open a window in the treatment of patients with ptosis.

10.
Clin Cancer Res ; 29(23): 4973-4989, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37725593

RESUMO

PURPOSE: Glioblastoma (GBM) is the most common aggressive primary malignant brain tumor in adults with a median age of onset of 68 to 70 years old. Although advanced age is often associated with poorer GBM patient survival, the predominant source(s) of maladaptive aging effects remains to be established. Here, we studied intratumoral and extratumoral relationships between adult patients with GBM and mice with brain tumors across the lifespan. EXPERIMENTAL DESIGN: Electronic health records at Northwestern Medicine and the NCI SEER databases were evaluated for GBM patient age and overall survival. The commercial Tempus and Caris databases, as well as The Cancer Genome Atlas were profiled for gene expression, DNA methylation, and mutational changes with varying GBM patient age. In addition, gene expression analysis was performed on the extratumoral brain of younger and older adult mice with or without a brain tumor. The survival of young and old wild-type or transgenic (INK-ATTAC) mice with a brain tumor was evaluated after treatment with or without senolytics and/or immunotherapy. RESULTS: Human patients with GBM ≥65 years of age had a significantly decreased survival compared with their younger counterparts. While the intra-GBM molecular profiles were similar between younger and older patients with GBM, non-tumor brain tissue had a significantly different gene expression profile between young and old mice with a brain tumor and the eradication of senescent cells improved immunotherapy-dependent survival of old but not young mice. CONCLUSIONS: This work suggests a potential benefit for combining senolytics with immunotherapy in older patients with GBM.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Humanos , Animais , Camundongos , Idoso , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Glioblastoma/metabolismo , Senoterapia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Mutação , Metilação de DNA
11.
Front Bioeng Biotechnol ; 10: 900644, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35979170

RESUMO

The clinical application of intracranial compliance (ICC), ∆V/∆P, as one of the most critical indexes for hydrocephalus evaluation was demonstrated previously. We suggest a new definition for the concept of ICC (long-term ICC) where there is a longer amount of elapsed time (up to 18 months after shunting) between the measurement of two values (V1 and V2 or P1 and P2). The head images of 15 adult patients with communicating hydrocephalus were provided with nine sets of imaging in nine stages: prior to shunting, and 1, 2, 3, 6, 9, 12, 15, and 18 months after shunting. In addition to measuring CSF volume (CSFV) in each stage, intracranial pressure (ICP) was also calculated using fluid-structure interaction simulation for the noninvasive calculation of ICC. Despite small increases in the brain volume (16.9%), there were considerable decreases in the ICP (70.4%) and CSFV (80.0%) of hydrocephalus patients after 18 months of shunting. The changes in CSFV, brain volume, and ICP values reached a stable condition 12, 15, and 6 months after shunting, respectively. The results showed that the brain tissue needs approximately two months to adapt itself to the fast and significant ICP reduction due to shunting. This may be related to the effect of the "viscous" component of brain tissue. The ICC trend between pre-shunting and the first month of shunting was descending for all patients with a "mean value" of 14.75 ± 0.6 ml/cm H2O. ICC changes in the other stages were oscillatory (nonuniform). Our noninvasive long-term ICC calculations showed a nonmonotonic trend in the CSFV-ICP graph, the lack of a linear relationship between ICC and ICP, and an oscillatory increase in ICC values during shunt treatment. The oscillatory changes in long-term ICC may reflect the clinical variations in hydrocephalus patients after shunting.

12.
Commun Biol ; 5(1): 1198, 2022 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-36344582

RESUMO

The unpredictable complexities in hydrocephalus shunt outcomes may be related to the recovery behavior of brain tissue after shunting. The simulated cerebrospinal fluid (CSF) velocity and intracranial pressure (ICP) over 15 months after shunting were validated by experimental data. The mean strain and creep of the brain had notable changes after shunting and their trends were monotonic. The highest stiffness of the hydrocephalic brain was in the first consolidation phase (between pre-shunting to 1 month after shunting). The viscous component overcame and damped the input load in the third consolidation phase (after the fifteenth month) and changes in brain volume were stopped. The long-intracranial elastance (long-IE) changed oscillatory after shunting and there was not a linear relationship between long-IE and ICP. We showed the long-term effect of the viscous component on brain recovery behavior of hydrocephalic brain. The results shed light on the brain recovery mechanism after shunting and the mechanisms for shunt failure.


Assuntos
Derivações do Líquido Cefalorraquidiano , Hidrocefalia , Humanos , Derivações do Líquido Cefalorraquidiano/métodos , Hidrocefalia/cirurgia , Pressão Intracraniana , Encéfalo/diagnóstico por imagem
13.
Cell Biosci ; 12(1): 43, 2022 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-35379326

RESUMO

BACKGROUND: Nuclear factor-κB is a multi-subunit transcription factor that plays a central role in cellular senescence. We previously reported that an increase in the p52 subunit is seen in senescent cells and aged tissue. In the current work, we examined the mechanism by which p52 is activated and whether the increase in p52 promotes senescence. RESULTS: Using both primary mouse embryonic fibroblasts (MEFs) and WI-38 human lung fibroblasts, we examined cells after serial passage and following prolonged culture. An increase in p52 was found in the nucleus relative to pre-senescent cells. The increase in p52 protein was not reflected by an increase in NFKB2 mRNA or by an increase in the abundance of upstream activating kinases, IKKα and NIK. To examine whether p52 promotes senescence, we over-expressed mature p52 in primary MEFs. Significantly more senescence was seen compared to control, a finding not seen with p52 mutated at critical DNA binding residues. In addition, blocking p52 nuclear translocation with the peptide inhibitor, SN52, decreased ß-galactosidase (ß-gal) formation. Subsequent filtration studies demonstrated that proteins in conditioned media (CM) were necessary for the increase in p52 and mass spectrometry identified S100A4 and cyclophilin A (CYPA) as potential factors in CM necessary for induction of p52. The requirement of these proteins in CM for induction of p52 was confirmed using depletion and supplementation studies. In addition, we found that activation of STAT3 signaling was required for the increase in p52. Finally, genome wide ChIP-sequencing analysis confirmed that there is an increase in p52 chromatin enrichment with senescence and identified several downstream factors whose expression is regulated by increased p52 binding. CONCLUSIONS: These results demonstrate that p52 nuclear translocation is increased in senescent cells by factors in conditioned media and that mature p52 induces cellular senescence. The data are consistent with the prior observation that p52 is elevated in aged tissue and support the hypothesis that p52 contributes to organismal aging.

14.
J Med Chem ; 65(23): 15642-15662, 2022 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-36410047

RESUMO

Indoleamine 2,3-dioxygenase 1 (IDO1) is a potent immunosuppressive enzyme that inhibits the antitumor immune response through both tryptophan metabolism and non-enzymatic functions. To date, most IDO1-targeted approaches have focused on inhibiting tryptophan metabolism. However, this class of drugs has failed to improve the overall survival of patients with cancer. Here, we developed and characterized proteolysis targeting chimeras (PROTACs) that degrade the IDO1 protein. IDO1-PROTACs were tested for their effects on IDO1 enzyme and non-enzyme activities. After screening a library of IDO1-PROTAC derivatives, a compound was identified that potently degraded the IDO1 protein through cereblon-mediated proteasomal degradation. The IDO1-PROTAC: (i) inhibited IDO1 enzyme activity and IDO1-mediated NF-κB phosphorylation in cultured human glioblastoma (GBM) cells, (ii) degraded the IDO1 protein within intracranial brain tumors in vivo, and (iii) mediated a survival benefit in mice with well-established brain tumors. This study identified and characterized a new IDO1 protein degrader with therapeutic potential for patients with glioblastoma.


Assuntos
Neoplasias Encefálicas , Indolamina-Pirrol 2,3,-Dioxigenase , Humanos , Animais , Camundongos , Triptofano , Quimera de Direcionamento de Proteólise , Neoplasias Encefálicas/tratamento farmacológico
15.
Cancers (Basel) ; 13(8)2021 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-33919596

RESUMO

The treatment of glioblastoma (GBM) remains a significant challenge, with outcome for most pa-tients remaining poor. Although novel therapies have been developed, several obstacles restrict the incentive of drug developers to continue these efforts including the exorbitant cost, high failure rate and relatively small patient population. Repositioning drugs that have well-characterized mechanistic and safety profiles is an attractive alternative for drug development in GBM. In ad-dition, the relative ease with which repurposed agents can be transitioned to the clinic further supports their potential for examination in patients. Here, a systematic analysis of the literature and clinical trials provides a comprehensive review of primary articles and unpublished trials that use repurposed drugs for the treatment of GBM. The findings demonstrate that numerous drug classes that have a range of initial indications have efficacy against preclinical GBM models and that certain agents have shown significant potential for clinical benefit. With examination in randomized, placebo-controlled trials and the targeting of particular GBM subgroups, it is pos-sible that repurposing can be a cost-effective approach to identify agents for use in multimodal anti-GBM strategies.

16.
Sci Rep ; 11(1): 5665, 2021 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-33707466

RESUMO

The alkylating agent, temozolomide (TMZ), is the most commonly used chemotherapeutic for the treatment of glioblastoma (GBM). The anti-glioma effect of TMZ involves a complex response that includes G2-M cell cycle arrest and cyclin-dependent kinase 1 (CDK1) activation. While CDK1 phosphorylation is a well-described consequence of TMZ treatment, we find that TMZ also robustly induces CDK1 expression. Analysis of this pathway demonstrates that CDK1 is regulated by NF-κB via a putative κB-site in its proximal promoter. CDK1 was induced in a manner dependent on mature p50 and the atypical inhibitor κB protein, BCL-3. Treatment with TMZ induced binding of NF-κB to the κB-site as assessed by gel shift analysis and chromatin immunoprecipitation. Examination of a CDK1 promoter-reporter demonstrated the functional relevance of the κB-site and underlined the requirement of p50 and BCL-3 for activation. Targeted knockdown of CDK1 or chemical inhibition with the selective CDK1 inhibitor, RO-3306, potentiated the cytotoxic effect of TMZ. These results identify CDK1 as an NF-κB target gene regulated by p50 and BCL-3 and suggest that targeting CDK1 may be a strategy to improve the efficacy of TMZ against GBM.


Assuntos
Neoplasias Encefálicas/metabolismo , Proteína Quinase CDC2/metabolismo , Glioblastoma/metabolismo , NF-kappa B/metabolismo , Temozolomida/farmacologia , Proteína 3 do Linfoma de Células B/metabolismo , Sequência de Bases , Sítios de Ligação , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Proteína Quinase CDC2/genética , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioblastoma/genética , Glioblastoma/patologia , Humanos , Regiões Promotoras Genéticas/genética
17.
Neurooncol Adv ; 3(1): vdab125, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34647022

RESUMO

BACKGROUND: Advanced age is a major risk factor for the development of many diseases including those affecting the central nervous system. Wild-type isocitrate dehydrogenase glioblastoma (IDHwt GBM) is the most common primary malignant brain cancer and accounts for ≥90% of all adult GBM diagnoses. Patients with IDHwt GBM have a median age of diagnosis at 68-70 years of age, and increasing age is associated with an increasingly worse prognosis for patients with this type of GBM. METHODS: The Surveillance, Epidemiology, and End Results, The Cancer Genome Atlas, and the Chinese Glioma Genome Atlas databases were analyzed for mortality indices. Meta-analysis of 80 clinical trials was evaluated for log hazard ratio for aging to tumor survivorship. RESULTS: Despite significant advances in the understanding of intratumoral genetic alterations, molecular characteristics of tumor microenvironments, and relationships between tumor molecular characteristics and the use of targeted therapeutics, life expectancy for older adults with GBM has yet to improve. CONCLUSIONS: Based upon the results of our analysis, we propose that age-dependent factors that are yet to be fully elucidated, contribute to IDHwt GBM patient outcomes.

18.
Nat Commun ; 11(1): 5007, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-33024116

RESUMO

p50, the mature product of NFKB1, is constitutively produced from its precursor, p105. Here, we identify BARD1 as a p50-interacting factor. p50 directly associates with the BARD1 BRCT domains via a C-terminal phospho-serine motif. This interaction is induced by ATR and results in mono-ubiquitination of p50 by the BARD1/BRCA1 complex. During the cell cycle, p50 is mono-ubiquitinated in S phase and loss of this post-translational modification increases S phase progression and chromosomal breakage. Genome-wide studies reveal a substantial decrease in p50 chromatin enrichment in S phase and Cycln E is identified as a factor regulated by p50 during the G1 to S transition. Functionally, interaction with BARD1 promotes p50 protein stability and consistent with this, in human cancer specimens, low nuclear BARD1 protein strongly correlates with low nuclear p50. These data indicate that p50 mono-ubiquitination by BARD1/BRCA1 during the cell cycle regulates S phase progression to maintain genome integrity.


Assuntos
Neoplasias da Mama/metabolismo , Ciclo Celular/fisiologia , Instabilidade Genômica , Subunidade p50 de NF-kappa B/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Animais , Sítios de Ligação , Neoplasias da Mama/mortalidade , Linhagem Celular Tumoral , Feminino , Fibroblastos , Humanos , Lisina/metabolismo , Camundongos , Subunidade p50 de NF-kappa B/genética , Neuroblastoma/metabolismo , Domínios Proteicos , Processamento de Proteína Pós-Traducional , Serina/metabolismo , Proteínas Supressoras de Tumor/genética , Ubiquitina-Proteína Ligases/genética , Ubiquitinação
19.
Cancer Res ; 67(14): 6889-98, 2007 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-17638900

RESUMO

The alkylating agent temozolomide, commonly used in the treatment of malignant glioma, causes cellular cytotoxicity by forming O(6)-methylguanine adducts. In this report, we investigated whether temozolomide alters the activity of the transcription factor nuclear factor-kappaB (NF-kappaB). Temozolomide inhibits basal and tumor necrosis factor alpha (TNFalpha)-induced NF-kappaB transcriptional activity without altering phosphorylation or degradation of inhibitor of kappaB-alpha. Inhibition of NF-kappaB is secondary to attenuation of p65 DNA binding, not nuclear translocation. Inhibition of DNA binding is shown both in vitro, with gel shift studies and DNA binding assays, and in vivo at kappaB sites. Consistent with inhibition of NF-kappaB activity, temozolomide reduces basal and TNFalpha-induced kappaB-dependent gene expression. Temozolomide also inhibits NF-kappaB activated by inducers other than TNFalpha, including lipopolysaccharide, doxorubicin, and phorbol 12-myristate 13-acetate. The inhibitory action of temozolomide on NF-kappaB is observed to be maximal following pretreatment of cells with temozolomide for 16 h and is also seen with the S(N)1-type methylating agent methylnitrosourea. The ability of temozolomide to form O(6)-methylguanine adducts is important for inhibition of NF-kappaB as is the presence of a functioning mismatch repair system. Activation of NF-kappaB with TNFalpha before administration of temozolomide reduces the cytotoxicity of temozolomide, whereas 16-h pretreatment with temozolomide resensitizes cells to killing. This work shows a mechanism whereby O(6)-methylguanine adducts formed by temozolomide lead to inhibition of NF-kappaB activity and illustrates a link between mismatch repair processing of alkylator-induced DNA damage and cell death.


Assuntos
Dacarbazina/análogos & derivados , Guanina/análogos & derivados , NF-kappa B/metabolismo , Fator de Transcrição RelA/metabolismo , Transporte Ativo do Núcleo Celular , Antineoplásicos Alquilantes/farmacologia , Linhagem Celular Tumoral , Dano ao DNA , Dacarbazina/farmacologia , Guanina/química , Humanos , Luciferases/metabolismo , Microscopia de Fluorescência , Ligação Proteica , Frações Subcelulares/metabolismo , Temozolomida , Acetato de Tetradecanoilforbol/farmacologia , Fatores de Tempo , Fator de Transcrição RelA/antagonistas & inibidores
20.
World Neurosurg ; 125: 32-36, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30703592

RESUMO

BACKGROUND: Differential diagnosis of sellar masses includes adenoma, meningioma, craniopharyngioma, and metastasis. Primary paraganglioma is seldom considered. We present a case of this unique pathology, review the relevant literature, and compile a compendium of immunohistochemical characteristics for use as a resource. CASE DESCRIPTION: A 73-year-old woman presented to the hospital with visual changes in her left hemifield. Noncontrast head computed tomography demonstrated a large sellar mass with suprasellar extension and displacement of the optic chiasm (diameter of 3.1 cm). Magnetic resonance imaging was unobtainable owing to an incompatible pacemaker. Computed tomography characterization was most consistent with a macroadenoma. Given the acute visual decline, surgical decompression via an endonasal transsphenoidal route was performed without complication. A diagnosis of paraganglioma was made based on histopathology. Following resection, the patient's visual field deficit improved. Computed tomography body imaging was negative for a metastatic origin. CONCLUSIONS: Paraganglioma is a rare but potential differential diagnosis to consider when evaluating sellar masses.


Assuntos
Adenoma/diagnóstico por imagem , Quiasma Óptico/diagnóstico por imagem , Paraganglioma/diagnóstico por imagem , Neoplasias Hipofisárias/diagnóstico por imagem , Sela Túrcica/diagnóstico por imagem , Adenoma/cirurgia , Idoso , Diagnóstico Diferencial , Feminino , Humanos , Quiasma Óptico/química , Quiasma Óptico/cirurgia , Paraganglioma/cirurgia , Neoplasias Hipofisárias/cirurgia , Sela Túrcica/química , Sela Túrcica/cirurgia
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