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1.
Cell ; 159(2): 402-14, 2014 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-25303533

RESUMO

Identification of driver mutations in human diseases is often limited by cohort size and availability of appropriate statistical models. We propose a framework for the systematic discovery of genetic alterations that are causal determinants of disease, by prioritizing genes upstream of functional disease drivers, within regulatory networks inferred de novo from experimental data. We tested this framework by identifying the genetic determinants of the mesenchymal subtype of glioblastoma. Our analysis uncovered KLHL9 deletions as upstream activators of two previously established master regulators of the subtype, C/EBPß and C/EBPδ. Rescue of KLHL9 expression induced proteasomal degradation of C/EBP proteins, abrogated the mesenchymal signature, and reduced tumor viability in vitro and in vivo. Deletions of KLHL9 were confirmed in > 50% of mesenchymal cases in an independent cohort, thus representing the most frequent genetic determinant of the subtype. The method generalized to study other human diseases, including breast cancer and Alzheimer's disease.


Assuntos
Algoritmos , Redes Reguladoras de Genes , Glioblastoma/genética , Mutação , Doença de Alzheimer/genética , Animais , Neoplasias da Mama/genética , Proteína delta de Ligação ao Facilitador CCAAT/metabolismo , Variações do Número de Cópias de DNA , Glioblastoma/patologia , Xenoenxertos , Humanos , Camundongos , Transplante de Neoplasias , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas/metabolismo , Locos de Características Quantitativas , Ubiquitinação
3.
Nature ; 551(7679): 247-250, 2017 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-29088702

RESUMO

Acquired drug resistance prevents cancer therapies from achieving stable and complete responses. Emerging evidence implicates a key role for non-mutational drug resistance mechanisms underlying the survival of residual cancer 'persister' cells. The persister cell pool constitutes a reservoir from which drug-resistant tumours may emerge. Targeting persister cells therefore presents a therapeutic opportunity to impede tumour relapse. We previously found that cancer cells in a high mesenchymal therapy-resistant cell state are dependent on the lipid hydroperoxidase GPX4 for survival. Here we show that a similar therapy-resistant cell state underlies the behaviour of persister cells derived from a wide range of cancers and drug treatments. Consequently, we demonstrate that persister cells acquire a dependency on GPX4. Loss of GPX4 function results in selective persister cell ferroptotic death in vitro and prevents tumour relapse in mice. These findings suggest that targeting of GPX4 may represent a therapeutic strategy to prevent acquired drug resistance.


Assuntos
Apoptose/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Glutationa Peroxidase/antagonistas & inibidores , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Animais , Antioxidantes/metabolismo , Avaliação Pré-Clínica de Medicamentos , Feminino , Humanos , Ferro/metabolismo , Masculino , Mesoderma/efeitos dos fármacos , Mesoderma/enzimologia , Mesoderma/patologia , Camundongos , Terapia de Alvo Molecular , Neoplasias/enzimologia , Fosfolipídeo Hidroperóxido Glutationa Peroxidase , Recidiva , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Nature ; 547(7664): 453-457, 2017 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-28678785

RESUMO

Plasticity of the cell state has been proposed to drive resistance to multiple classes of cancer therapies, thereby limiting their effectiveness. A high-mesenchymal cell state observed in human tumours and cancer cell lines has been associated with resistance to multiple treatment modalities across diverse cancer lineages, but the mechanistic underpinning for this state has remained incompletely understood. Here we molecularly characterize this therapy-resistant high-mesenchymal cell state in human cancer cell lines and organoids and show that it depends on a druggable lipid-peroxidase pathway that protects against ferroptosis, a non-apoptotic form of cell death induced by the build-up of toxic lipid peroxides. We show that this cell state is characterized by activity of enzymes that promote the synthesis of polyunsaturated lipids. These lipids are the substrates for lipid peroxidation by lipoxygenase enzymes. This lipid metabolism creates a dependency on pathways converging on the phospholipid glutathione peroxidase (GPX4), a selenocysteine-containing enzyme that dissipates lipid peroxides and thereby prevents the iron-mediated reactions of peroxides that induce ferroptotic cell death. Dependency on GPX4 was found to exist across diverse therapy-resistant states characterized by high expression of ZEB1, including epithelial-mesenchymal transition in epithelial-derived carcinomas, TGFß-mediated therapy-resistance in melanoma, treatment-induced neuroendocrine transdifferentiation in prostate cancer, and sarcomas, which are fixed in a mesenchymal state owing to their cells of origin. We identify vulnerability to ferroptic cell death induced by inhibition of a lipid peroxidase pathway as a feature of therapy-resistant cancer cells across diverse mesenchymal cell-state contexts.


Assuntos
Glutationa Peroxidase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Neoplasias/enzimologia , Caderinas/metabolismo , Morte Celular , Linhagem Celular Tumoral , Linhagem da Célula , Transdiferenciação Celular , Resistencia a Medicamentos Antineoplásicos/genética , Transição Epitelial-Mesenquimal , Humanos , Ferro/metabolismo , Peróxidos Lipídicos/metabolismo , Masculino , Melanoma/tratamento farmacológico , Melanoma/enzimologia , Melanoma/metabolismo , Melanoma/patologia , Mesoderma/efeitos dos fármacos , Mesoderma/enzimologia , Mesoderma/metabolismo , Mesoderma/patologia , Neoplasias/genética , Neoplasias/patologia , Fosfolipídeo Hidroperóxido Glutationa Peroxidase , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/enzimologia , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Proteômica , Proteínas Proto-Oncogênicas B-raf/genética , Reprodutibilidade dos Testes , Homeobox 1 de Ligação a E-box em Dedo de Zinco/genética
5.
Opt Express ; 29(18): 29044-29055, 2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-34615022

RESUMO

With the capabilities of diffractive optics there is a rising demand for determining the light interaction of diffractive elements with arbitrary illumination and scenery. Since the structured surfaces' scale lies within the visible wavelengths and below, the light's interaction cannot be simulated with state of the art geometric optic rendering approaches. This paper presents a new model for the inclusion of wave-optical effects into Monte Carlo path rendering concepts. The derived method allows the coupling of a rigorous full-field approach with the concept of backward ray propagation through complex scenes. Therefore, the rendering of arbitrarily structured periodic optical components is now possible for complex sceneries for design, verification and testing purposes. The method's performance is demonstrated by comparing rendering results of complex sceneries including CDs with corresponding photographs.

6.
J Neurooncol ; 155(3): 363-372, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34761331

RESUMO

BACKGROUND/PURPOSE: Glioblastoma (GBM) is the most common primary malignant brain tumor. Sex has been shown to be an important prognostic factor for GBM. The purpose of this study was to develop and independently validate sex-specific nomograms for estimation of individualized GBM survival probabilities using data from 2 independent NRG Oncology clinical trials. METHODS: This analysis included information on 752 (NRG/RTOG 0525) and 599 (NRG/RTOG 0825) patients with newly diagnosed GBM. The Cox proportional hazard models by sex were developed using NRG/RTOG 0525 and significant variables were identified using a backward selection procedure. The final selected models by sex were then independently validated using NRG/RTOG 0825. RESULTS: Final nomograms were built by sex. Age at diagnosis, KPS, MGMT promoter methylation and location of tumor were common significant predictors of survival for both sexes. For both sexes, tumors in the frontal lobes had significantly better survival than tumors of multiple sites. Extent of resection, and use of corticosteroids were significant predictors of survival for males. CONCLUSIONS: A sex specific nomogram that assesses individualized survival probabilities (6-, 12- and 24-months) for patients with GBM could be more useful than estimation of overall survival as there are factors that differ between males and females. A user friendly online application can be found here- https://npatilshinyappcalculator.shinyapps.io/SexDifferencesInGBM/ .


Assuntos
Neoplasias Encefálicas , Glioblastoma , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/terapia , Feminino , Glioblastoma/diagnóstico , Glioblastoma/genética , Glioblastoma/terapia , Humanos , Masculino , Nomogramas , Prognóstico , Regiões Promotoras Genéticas , Modelos de Riscos Proporcionais
7.
Opt Express ; 28(24): 37004-37014, 2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-33379782

RESUMO

Freeform optics generating specific irradiance distributions have been used in various applications for some time now. While most freeform optics design algorithms assume point sources or perfectly collimated light, the search for algorithms for non-idealized light sources with finite spatial as well as angular extent is still ongoing. In this work, such an approach is presented where the resulting irradiance distribution of a freeform optical surface is calculated as a superposition of pinhole images generated by points on the optical surface. To compute the required arrangement of the pinhole images for a prescribed irradiance pattern, the expectation maximization algorithm from statistics is applied. The result is then combined with a ray-targeting approach for finding the shape of the corresponding freeform optical surface. At its current state, the approach is applicable to Gaussian input irradiances, single-sided freeform optics and for the paraxial case. An example freeform optical surface for laser material processing is shown and discussed demonstrating the performance and the limitations of the presented approach.

8.
Int J Cancer ; 145(7): 1889-1901, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30861105

RESUMO

This clinical trial evaluated whether whole exome sequencing (WES) and RNA sequencing (RNAseq) of paired normal and tumor tissues could be incorporated into a personalized treatment plan for newly diagnosed patients (<25 years of age) with diffuse intrinsic pontine glioma (DIPG). Additionally, whole genome sequencing (WGS) was compared to WES to determine if WGS would further inform treatment decisions, and whether circulating tumor DNA (ctDNA) could detect the H3K27M mutation to allow assessment of therapy response. Patients were selected across three Pacific Pediatric Neuro-Oncology Consortium member institutions between September 2014 and January 2016. WES and RNAseq were performed at diagnosis and recurrence when possible in a CLIA-certified laboratory. Patient-derived cell line development was attempted for each subject. Collection of blood for ctDNA was done prior to treatment and with each MRI. A specialized tumor board generated a treatment recommendation including up to four FDA-approved agents based upon the genomic alterations detected. A treatment plan was successfully issued within 21 business days from tissue collection for all 15 subjects, with 14 of the 15 subjects fulfilling the feasibility criteria. WGS results did not significantly deviate from WES-based therapy recommendations; however, WGS data provided further insight into tumor evolution and fidelity of patient-derived cell models. Detection of the H3F3A or HIST1H3B K27M (H3K27M) mutation using ctDNA was successful in 92% of H3K27M mutant cases. A personalized treatment recommendation for DIPG can be rendered within a multicenter setting using comprehensive next-generation sequencing technology in a clinically relevant timeframe.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias do Tronco Encefálico/tratamento farmacológico , Glioma Pontino Intrínseco Difuso/tratamento farmacológico , Sequenciamento do Exoma/métodos , Análise de Sequência de RNA/métodos , Sequenciamento Completo do Genoma/métodos , Adolescente , Adulto , Neoplasias do Tronco Encefálico/genética , Criança , Pré-Escolar , DNA Tumoral Circulante , Glioma Pontino Intrínseco Difuso/genética , Estudos de Viabilidade , Feminino , Histonas/genética , Humanos , Masculino , Terapia de Alvo Molecular/métodos , Projetos Piloto , Medicina de Precisão , Adulto Jovem
9.
Curr Neurol Neurosci Rep ; 18(4): 15, 2018 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-29525892

RESUMO

PURPOSE OF REVIEW: High-throughput genomic sequencing has identified alterations in the gene encoding human telomerase reverse transcriptase (TERT) as points of interest for elucidating the oncogenic mechanism of multiple different cancer types, including gliomas. In gliomas, the TERT promoter mutation (TPM) and resultant overexpression of TERT are observed mainly in the most aggressive (primary glioblastoma/grade IV astrocytoma) and the least aggressive (grade II oligodendroglioma) cases. This article reviews recent research on (1) the mechanism of TERT activation in glioma, (2) downstream consequences of TERT overexpression on glioma pathogenesis, and (3) targeting TPMs as a therapeutic strategy. RECENT FINDINGS: New molecular classifications for gliomas include using TPMs, where the mutant group demonstrates the worst prognosis. Though a canonical function of TERT is established in regard to telomere maintenance, recent studies on non-canonical functions of TERT explore varied roles of telomerase in tumor progression and maintenance. Somatic alterations of the TERT promoter present a promising target for novel therapeutics development in primary glioma treatment.


Assuntos
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/terapia , Glioma/genética , Glioma/terapia , Telomerase/genética , Astrocitoma , Glioblastoma/genética , Glioma/patologia , Humanos , Mutação , Regiões Promotoras Genéticas
10.
J Neurooncol ; 126(3): 397-404, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26559543

RESUMO

Glioblastoma (GBM) is the most common primary tumor of the CNS and carries a dismal prognosis. The aggressive invasion of GBM cells into the surrounding normal brain makes complete resection impossible, significantly increases resistance to the standard therapy regimen, and virtually assures tumor recurrence. Median survival for newly diagnosed GBM is 14.6 months and declines to 8 months for patients with recurrent GBM. New therapeutic strategies that target the molecular drivers of invasion are required for improved clinical outcome. We have demonstrated that TROY (TNFRSF19), a member of the TNFR super-family, plays an important role in GBM invasion and resistance. Knockdown of TROY expression inhibits GBM cell invasion, increases sensitivity to temozolomide, and prolongs survival in an intracranial xenograft model. Propentofylline (PPF), an atypical synthetic methylxanthine compound, has been extensively studied in Phase II and Phase III clinical trials for Alzheimer's disease and vascular dementia where it has demonstrated blood-brain permeability and minimal adverse side effects. Here we showed that PPF decreased GBM cell expression of TROY, inhibited glioma cell invasion, and sensitized GBM cells to TMZ. Mechanistically, PPF decreased glioma cell invasion by modulating TROY expression and downstream signaling, including AKT, NF-κB, and Rac1 activation. Thus, PPF may provide a pharmacologic approach to target TROY, inhibit cell invasion, and reduce therapeutic resistance in GBM.


Assuntos
Apoptose/efeitos dos fármacos , Neoplasias Encefálicas/prevenção & controle , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioblastoma/prevenção & controle , Receptores do Fator de Necrose Tumoral/metabolismo , Xantinas/farmacologia , Western Blotting , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Proliferação de Células/efeitos dos fármacos , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , NF-kappa B/metabolismo , Invasividade Neoplásica , Fármacos Neuroprotetores/farmacologia , Receptores do Fator de Necrose Tumoral/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Células Tumorais Cultivadas
11.
J Transl Med ; 13: 306, 2015 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-26381735

RESUMO

BACKGROUND: Constitutive MET signaling promotes invasiveness in most primary and recurrent GBM. However, deployment of available MET-targeting agents is confounded by lack of effective biomarkers for selecting suitable patients for treatment. Because endogenous HGF overexpression often causes autocrine MET activation, and also indicates sensitivity to MET inhibitors, we investigated whether it drives the expression of distinct genes which could serve as a signature indicating vulnerability to MET-targeted therapy in GBM. METHODS: Interrogation of genomic data from TCGA GBM (Student's t test, GBM patients with high and low HGF expression, p ≤ 0.00001) referenced against patient-derived xenograft (PDX) models (Student's t test, sensitive vs. insensitive models, p ≤ 0.005) was used to identify the HGF-dependent signature. Genomic analysis of GBM xenograft models using both human and mouse gene expression microarrays (Student's t test, treated vs. vehicle tumors, p ≤ 0.01) were performed to elucidate the tumor and microenvironment cross talk. A PDX model with EGFR(amp) was tested for MET activation as a mechanism of erlotinib resistance. RESULTS: We identified a group of 20 genes highly associated with HGF overexpression in GBM and were up- or down-regulated only in tumors sensitive to MET inhibitor. The MET inhibitors regulate tumor (human) and host (mouse) cells within the tumor via distinct molecular processes, but overall impede tumor growth by inhibiting cell cycle progression. EGFR (amp) tumors undergo erlotinib resistance responded to a combination of MET and EGFR inhibitors. CONCLUSIONS: Combining TCGA primary tumor datasets (human) and xenograft tumor model datasets (human tumor grown in mice) using therapeutic efficacy as an endpoint may serve as a useful approach to discover and develop molecular signatures as therapeutic biomarkers for targeted therapy. The HGF dependent signature may serve as a candidate predictive signature for patient enrollment in clinical trials using MET inhibitors. Human and mouse microarrays maybe used to dissect the tumor-host interactions. Targeting MET in EGFR (amp) GBM may delay the acquired resistance developed during treatment with erlotinib.


Assuntos
Perfilação da Expressão Gênica , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Fator de Crescimento de Hepatócito/metabolismo , Terapia de Alvo Molecular , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Animais , Comunicação Autócrina/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Receptores ErbB/metabolismo , Cloridrato de Erlotinib/farmacologia , Cloridrato de Erlotinib/uso terapêutico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Genômica , Glioblastoma/patologia , Humanos , Camundongos , Modelos Biológicos , Invasividade Neoplásica , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas c-met/metabolismo , Resultado do Tratamento , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Carcinogenesis ; 35(1): 218-26, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23975833

RESUMO

The long-term survival of patients with glioblastoma is compromised by the proclivity for local invasion into the surrounding normal brain, escaping surgical resection and contributing to therapeutic resistance. Tumor necrosis factor-like weak inducer of apoptosis (TWEAK), a member of the tumor necrosis factor superfamily, can stimulate glioma cell invasion via binding to fibroblast growth factor-inducible 14 (Fn14) and subsequent activation of the Rho guanosine triphosphatase family member Rac1. Here, we demonstrate that TWEAK acts as a chemotactic factor for glioma cells, a potential process for driving cell invasion into the surrounding brain tissue. TWEAK exposure induced the activation of Src family kinases (SFKs), and pharmacologic suppression of SFK activity inhibited TWEAK-induced chemotactic migration. We employed a multiplexed Luminex assay and identified Lyn as a candidate SFK activated by TWEAK. Depletion of Lyn suppressed TWEAK-induced chemotaxis and Rac1 activity. Furthermore, Lyn gene expression levels increase with primary glioma tumor grade and inversely correlate with patient survival. These results show that TWEAK-induced glioma cell chemotaxis is dependent upon Lyn kinase function and, thus, provides opportunities for therapeutic targeting of this deadly disease.


Assuntos
Neoplasias Encefálicas/patologia , Quimiotaxia/fisiologia , Glioblastoma/patologia , Fatores de Necrose Tumoral/metabolismo , Quinases da Família src/metabolismo , Animais , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/mortalidade , Movimento Celular , Citocina TWEAK , Ativação Enzimática , Regulação Neoplásica da Expressão Gênica , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/mortalidade , Glioma/genética , Glioma/metabolismo , Glioma/patologia , Humanos , Ratos Wistar , Fatores de Necrose Tumoral/genética , Proteínas rac1 de Ligação ao GTP/genética , Proteínas rac1 de Ligação ao GTP/metabolismo , Quinases da Família src/genética
13.
J Biol Chem ; 288(45): 32261-32276, 2013 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-24056367

RESUMO

Deregulation of the TNF-like weak inducer of apoptosis (TWEAK)-fibroblast growth factor-inducible 14 (Fn14) signaling pathway is observed in many diseases, including inflammation, autoimmune diseases, and cancer. Activation of Fn14 signaling by TWEAK binding triggers cell invasion and survival and therefore represents an attractive pathway for therapeutic intervention. Based on structural studies of the TWEAK-binding cysteine-rich domain of Fn14, several homology models of TWEAK were built to investigate plausible modes of TWEAK-Fn14 interaction. Two promising models, centered on different anchoring residues of TWEAK (tyrosine 176 and tryptophan 231), were prioritized using a data-driven strategy. Site-directed mutagenesis of TWEAK at Tyr(176), but not Trp(231), resulted in the loss of TWEAK binding to Fn14 substantiating Tyr(176) as the anchoring residue. Importantly, mutation of TWEAK at Tyr(176) did not disrupt TWEAK trimerization but failed to induce Fn14-mediated nuclear factor κ-light chain enhancer of activated B cell (NF-κB) signaling. The validated structural models were utilized in a virtual screen to design a targeted library of small molecules predicted to disrupt the TWEAK-Fn14 interaction. 129 small molecules were screened iteratively, with identification of molecules producing up to 37% inhibition of TWEAK-Fn14 binding. In summary, we present a data-driven in silico study revealing key structural elements of the TWEAK-Fn14 interaction, followed by experimental validation, serving as a guide for the design of small molecule inhibitors of the TWEAK-Fn14 ligand-receptor interaction. Our results validate the TWEAK-Fn14 interaction as a chemically tractable target and provide the foundation for further exploration utilizing chemical biology approaches focusing on validating this system as a therapeutic target in invasive cancers.


Assuntos
Modelos Moleculares , Receptores do Fator de Necrose Tumoral , Fatores de Necrose Tumoral , Substituição de Aminoácidos , Linhagem Celular Tumoral , Citocina TWEAK , Células HEK293 , Humanos , Mutagênese Sítio-Dirigida , Mutação de Sentido Incorreto , Invasividade Neoplásica , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/química , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Neoplasias/química , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Estrutura Terciária de Proteína , Receptores do Fator de Necrose Tumoral/antagonistas & inibidores , Receptores do Fator de Necrose Tumoral/química , Receptores do Fator de Necrose Tumoral/genética , Receptores do Fator de Necrose Tumoral/metabolismo , Receptor de TWEAK , Inibidores do Fator de Necrose Tumoral , Fatores de Necrose Tumoral/química , Fatores de Necrose Tumoral/genética , Fatores de Necrose Tumoral/metabolismo
14.
Biomedicines ; 12(2)2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38398008

RESUMO

Glioblastoma (GB) is the most lethal brain cancer in adults, with a 5-year survival rate of 5%. The standard of care for GB includes maximally safe surgical resection, radiation, and temozolomide (TMZ) therapy, but tumor recurrence is inevitable in most GB patients. Here, we describe the development of a blood-brain barrier (BBB)-penetrant tubulin destabilizer, RGN3067, for the treatment of GB. RGN3067 shows good oral bioavailability and achieves high concentrations in rodent brains after oral dosing (Cmax of 7807 ng/mL (20 µM), Tmax at 2 h). RGN3067 binds the colchicine binding site of tubulin and inhibits tubulin polymerization. The compound also suppresses the proliferation of the GB cell lines U87 and LN-18, with IC50s of 117 and 560 nM, respectively. In four patient-derived GB cell lines, the IC50 values for RGN3067 range from 148 to 616 nM. Finally, in a patient-derived xenograft (PDX) mouse model, RGN3067 reduces the rate of tumor growth compared to the control. Collectively, we show that RGN3067 is a BBB-penetrant small molecule that shows in vitro and in vivo efficacy and that its design addresses many of the physicochemical properties that prevent the use of microtubule destabilizers as treatments for GB and other brain cancers.

15.
Res Sq ; 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38585839

RESUMO

Many cancers, including glioblastoma (GBM), have a male-biased sex difference in incidence and outcome. The underlying reasons for this sex bias are unclear but likely involve differences in tumor cell state and immune response. This effect is further amplified by sex hormones, including androgens, which have been shown to inhibit anti-tumor T cell immunity. Here, we show that androgens drive anti-tumor immunity in brain tumors, in contrast to its effect in other tumor types. Upon castration, tumor growth was accelerated with attenuated T cell function in GBM and brain tumor models, but the opposite was observed when tumors were located outside the brain. Activity of the hypothalamus-pituitary-adrenal gland (HPA) axis was increased in castrated mice, particularly in those with brain tumors. Blockade of glucocorticoid receptors reversed the accelerated tumor growth in castrated mice, indicating that the effect of castration was mediated by elevated glucocorticoid signaling. Furthermore, this mechanism was not GBM specific, but brain specific, as hyperactivation of the HPA axis was observed with intracranial implantation of non-GBM tumors in the brain. Together, our findings establish that brain tumors drive distinct endocrine-mediated mechanisms in the androgen-deprived setting and highlight the importance of organ-specific effects on anti-tumor immunity.

16.
Neurooncol Adv ; 6(1): vdae104, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39119276

RESUMO

Background: Neddylation (NAE) inhibition, affecting posttranslational protein function and turnover, is a promising therapeutic approach to cancer. We report the cytotoxic vulnerability to NAE inhibitors in a subset of glioblastoma (GBM) preclinical models and identify genetic alterations and biological processes underlying differential response. Methods: GBM DNA sequencing and transcriptomic data were queried for genes associated with response to NAE inhibition; candidates were validated by molecular techniques. Multi-omics and functional assays revealed processes implicated in NAE inhibition response. Results: Transcriptomics and shotgun proteomics depict PTEN signaling, DNA replication, and DNA repair pathways as significant differentiators between sensitive and resistant models. Vulnerability to MLN4924, a NAE inhibitor, is associated with elevated S-phase populations, DNA re-replication, and DNA damage. In a panel of GBM models, loss of WT PTEN is associated with resistance to different NAE inhibitors. A NAE inhibition response gene set could segregate the GBM cell lines that are most resistant to MLN4924. Conclusions: Loss of WT PTEN is associated with non-sensitivity to 3 different compounds that inhibit NAE in GBM. A NAE inhibition response gene set largely consisting of DNA replication genes could segregate GBM cell lines most resistant to NAEi and may be the basis for future development of NAE inhibition signatures of vulnerability and clinical trial enrollment within a precision medicine paradigm.

17.
Clin Cancer Res ; 30(15): 3167-3178, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38836759

RESUMO

PURPOSE: Patients with glioblastoma (GBM) have a dismal prognosis. Although the DNA alkylating agent temozolomide (TMZ) is the mainstay of chemotherapy, therapeutic resistance rapidly develops in patients. Base excision repair inhibitor TRC102 (methoxyamine) reverses TMZ resistance in preclinical glioma models. We aimed to investigate the efficacy and safety of oral TRC102+TMZ in recurrent GBM (rGBM). PATIENTS AND METHODS: A preregistered (NCT02395692), nonrandomized, multicenter, phase 2 clinical trial (BERT) was planned and conducted through the Adult Brain Tumor Consortium (ABTC-1402). Arm 1 included patients with bevacizumab-naïve GBM at the first recurrence, with the primary endpoint of response rates. If sufficient activity was identified, a second arm was planned for the bevacizumab-refractory patients. The secondary endpoints were overall survival (OS), progression-free survival (PFS), PFS at 6 months (PFS6), and toxicity. RESULTS: Arm 1 enrolled 19 patients with a median of two treatment cycles. Objective responses were not observed; hence, arm 2 did not open. The median OS was 11.1 months [95% confidence interval (CI), 8.2-17.9]. The median PFS was 1.9 months (95% CI, 1.8-3.7). The PFS6 was 10.5% (95% CI, 1.3%-33.1%). Most toxicities were grades 1 and 2, with two grade 3 lymphopenias and one grade 4 thrombocytopenia. Two patients with PFS ≥ 17 months and OS > 32 months were deemed "extended survivors." RNA sequencing of tumor tissue, obtained at diagnosis, demonstrated significantly enriched signatures of DNA damage response (DDR), chromosomal instability (CIN70, CIN25), and cellular proliferation (PCNA25) in "extended survivors." CONCLUSIONS: These findings confirm the safety and feasibility of TRC102+TMZ in patients with rGBM. They also warrant further evaluation of combination therapy in biomarker-enriched trials enrolling GBM patients with baseline hyperactivated DDR pathways.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Recidiva Local de Neoplasia , Temozolomida , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/mortalidade , Reparo por Excisão/efeitos dos fármacos , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Glioblastoma/genética , Glioblastoma/mortalidade , Hidroxilaminas/uso terapêutico , Hidroxilaminas/administração & dosagem , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/patologia , Prognóstico , Temozolomida/uso terapêutico , Temozolomida/administração & dosagem
18.
BMC Genomics ; 14: 110, 2013 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-23418942

RESUMO

BACKGROUND: Identifying similarities and differences in the molecular constitutions of various types of cancer is one of the key challenges in cancer research. The appearances of a cancer depend on complex molecular interactions, including gene regulatory networks and gene-environment interactions. This complexity makes it challenging to decipher the molecular origin of the cancer. In recent years, many studies reported methods to uncover heterogeneous depictions of complex cancers, which are often categorized into different subtypes. The challenge is to identify diverse molecular contexts within a cancer, to relate them to different subtypes, and to learn underlying molecular interactions specific to molecular contexts so that we can recommend context-specific treatment to patients. RESULTS: In this study, we describe a novel method to discern molecular interactions specific to certain molecular contexts. Unlike conventional approaches to build modular networks of individual genes, our focus is to identify cancer-generic and subtype-specific interactions between contextual gene sets, of which each gene set share coherent transcriptional patterns across a subset of samples, termed contextual gene set. We then apply a novel formulation for quantitating the effect of the samples from each subtype on the calculated strength of interactions observed. Two cancer data sets were analyzed to support the validity of condition-specificity of identified interactions. When compared to an existing approach, the proposed method was much more sensitive in identifying condition-specific interactions even in heterogeneous data set. The results also revealed that network components specific to different types of cancer are related to different biological functions than cancer-generic network components. We found not only the results that are consistent with previous studies, but also new hypotheses on the biological mechanisms specific to certain cancer types that warrant further investigations. CONCLUSIONS: The analysis on the contextual gene sets and characterization of networks of interaction composed of these sets discovered distinct functional differences underlying various types of cancer. The results show that our method successfully reveals many subtype-specific regions in the identified maps of biological contexts, which well represent biological functions that can be connected to specific subtypes.


Assuntos
Regulação Neoplásica da Expressão Gênica/fisiologia , Redes Reguladoras de Genes , Interação Gene-Ambiente , Glioblastoma/fisiopatologia , Neoplasias/fisiopatologia , Proteínas de Transporte/genética , Colesterol/biossíntese , Proteínas de Ligação a DNA , Bases de Dados Genéticas , Regulação para Baixo , Glioblastoma/genética , Humanos , Receptores de Superfície Celular/genética , Regulação para Cima , Vocabulário Controlado
19.
Methods Mol Biol ; 2590: 1-30, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36335489

RESUMO

Human DNA sequencing protocols have revolutionized human biology, biomedical science, and clinical practice, but still have very important limitations. One limitation is that most protocols do not separate or assemble (i.e., "phase") the nucleotide content of each of the maternally and paternally derived chromosomal homologs making up the 22 autosomal pairs and the chromosomal pair making up the pseudo-autosomal region of the sex chromosomes. This has led to a dearth of studies and a consequent underappreciation of many phenomena of fundamental importance to basic and clinical genomic science. We discuss a few protocols for obtaining phase information as well as their limitations, including those that could be used in tumor phasing settings. We then describe a number of biological and clinical phenomena that require phase information. These include phenomena that require precise knowledge of the nucleotide sequence in a chromosomal segment from germline or somatic cells, such as DNA binding events, and insight into unique cis vs. trans-acting functionally impactful variant combinations-for example, variants implicated in a phenotype governed by compound heterozygosity. In addition, we also comment on the need for reliable and consensus-based diploid-context computational workflows for variant identification as well as the need for laboratory-based functional verification strategies for validating cis vs. trans effects of variant combinations. We also briefly describe available resources, example studies, as well as areas of further research, and ultimately argue that the science behind the study of human diploidy, referred to as "diplomics," which will be enabled by nucleotide-level resolution of phased genomes, is a logical next step in the analysis of human genome biology.


Assuntos
Diploide , Genoma Humano , Humanos , Haplótipos , Sequência de Bases , Nucleotídeos , Análise de Sequência de DNA , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Biologia Computacional
20.
Proc (Bayl Univ Med Cent) ; 36(1): 1-7, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36578607

RESUMO

A detailed understanding of the molecular and immunological changes that occur longitudinally across tumors exposed to immune checkpoint inhibitors is a significant knowledge gap in oncology. To address this unmet need, we created a statewide biospecimen collection and clinical informatics system to enable longitudinal tumor and immune profiling and to enhance translational research. The Texas Immuno-Oncology Biorepository (TIOB) consents patients to collect, process, store, and analyze serial biospecimens of tissue, blood, urine, and stool from a diverse population of over 100,000 cancer patients treated each year across the Baylor Scott & White Health system. Here we sought to demonstrate that these samples were fit for purpose with regard to downstream multi-omic assays. Plasma, urine, peripheral blood mononuclear cells, and stool samples from 11 enrolled patients were collected from various cancer types. RNA isolated from extracellular vesicles derived from plasma and urine was sufficient for transcriptomics. Peripheral blood mononuclear cells demonstrated excellent yield and viability. Ten of 11 stool samples produced RNA quality to enable microbiome characterization. Sample acquisition and processing methods are known to impact sample quality and performance. We demonstrate that consistent acquisition methodology, sample preparation, and sample storage employed by the TIOB can produce high-quality specimens, suited for employment in a wide array of multi-omic platforms, enabling comprehensive immune and molecular profiling.

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