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1.
Cell ; 185(9): 1506-1520.e17, 2022 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-35385687

RESUMO

Schistosomes cause morbidity and death throughout the developing world due to the massive numbers of eggs female worms deposit into the blood of their host. Studies dating back to the 1920s show that female schistosomes rely on constant physical contact with a male worm both to become and remain sexually mature; however, the molecular details governing this process remain elusive. Here, we uncover a nonribosomal peptide synthetase that is induced in male worms upon pairing with a female and find that it is essential for the ability of male worms to stimulate female development. We demonstrate that this enzyme generates ß-alanyl-tryptamine that is released by paired male worms. Furthermore, synthetic ß-alanyl-tryptamine can replace male worms to stimulate female sexual development and egg laying. These data reveal that peptide-based pheromone signaling controls female schistosome sexual maturation, suggesting avenues for therapeutic intervention and uncovering a role for nonribosomal peptides as metazoan signaling molecules.


Assuntos
Peptídeos , Feromônios , Schistosoma/crescimento & desenvolvimento , Animais , Feminino , Masculino , Biossíntese de Peptídeos Independentes de Ácido Nucleico , Triptaminas
2.
Cell ; 184(10): 2715-2732.e23, 2021 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-33852912

RESUMO

Traumatic brain injury (TBI) is the largest non-genetic, non-aging related risk factor for Alzheimer's disease (AD). We report here that TBI induces tau acetylation (ac-tau) at sites acetylated also in human AD brain. This is mediated by S-nitrosylated-GAPDH, which simultaneously inactivates Sirtuin1 deacetylase and activates p300/CBP acetyltransferase, increasing neuronal ac-tau. Subsequent tau mislocalization causes neurodegeneration and neurobehavioral impairment, and ac-tau accumulates in the blood. Blocking GAPDH S-nitrosylation, inhibiting p300/CBP, or stimulating Sirtuin1 all protect mice from neurodegeneration, neurobehavioral impairment, and blood and brain accumulation of ac-tau after TBI. Ac-tau is thus a therapeutic target and potential blood biomarker of TBI that may represent pathologic convergence between TBI and AD. Increased ac-tau in human AD brain is further augmented in AD patients with history of TBI, and patients receiving the p300/CBP inhibitors salsalate or diflunisal exhibit decreased incidence of AD and clinically diagnosed TBI.


Assuntos
Doença de Alzheimer/etiologia , Doença de Alzheimer/prevenção & controle , Lesões Encefálicas Traumáticas/complicações , Neuroproteção , Proteínas tau/metabolismo , Acetilação , Doença de Alzheimer/metabolismo , Animais , Anti-Inflamatórios não Esteroides/uso terapêutico , Biomarcadores/sangue , Biomarcadores/metabolismo , Lesões Encefálicas Traumáticas/metabolismo , Linhagem Celular , Diflunisal/uso terapêutico , Feminino , Gliceraldeído-3-Fosfato Desidrogenase (Fosforiladora) , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/metabolismo , Salicilatos/uso terapêutico , Sirtuína 1/metabolismo , Fatores de Transcrição de p300-CBP/antagonistas & inibidores , Fatores de Transcrição de p300-CBP/metabolismo , Proteínas tau/sangue
3.
Cell ; 173(4): 864-878.e29, 2018 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-29681454

RESUMO

Diversity in the genetic lesions that cause cancer is extreme. In consequence, a pressing challenge is the development of drugs that target patient-specific disease mechanisms. To address this challenge, we employed a chemistry-first discovery paradigm for de novo identification of druggable targets linked to robust patient selection hypotheses. In particular, a 200,000 compound diversity-oriented chemical library was profiled across a heavily annotated test-bed of >100 cellular models representative of the diverse and characteristic somatic lesions for lung cancer. This approach led to the delineation of 171 chemical-genetic associations, shedding light on the targetability of mechanistic vulnerabilities corresponding to a range of oncogenotypes present in patient populations lacking effective therapy. Chemically addressable addictions to ciliogenesis in TTC21B mutants and GLUT8-dependent serine biosynthesis in KRAS/KEAP1 double mutants are prominent examples. These observations indicate a wealth of actionable opportunities within the complex molecular etiology of cancer.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/patologia , Proliferação de Células/efeitos dos fármacos , Neoplasias Pulmonares/patologia , Bibliotecas de Moléculas Pequenas/farmacologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Linhagem Celular Tumoral , Família 4 do Citocromo P450/deficiência , Família 4 do Citocromo P450/genética , Descoberta de Drogas , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Glucocorticoides/farmacologia , Proteínas Facilitadoras de Transporte de Glucose/antagonistas & inibidores , Proteínas Facilitadoras de Transporte de Glucose/genética , Proteínas Facilitadoras de Transporte de Glucose/metabolismo , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Neoplasias Pulmonares/metabolismo , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Mutação , Fator 2 Relacionado a NF-E2/antagonistas & inibidores , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Receptor Notch2/genética , Receptor Notch2/metabolismo , Receptores de Glucocorticoides/antagonistas & inibidores , Receptores de Glucocorticoides/genética , Receptores de Glucocorticoides/metabolismo , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/metabolismo
4.
Cell ; 155(3): 552-66, 2013 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-24243015

RESUMO

Context-specific molecular vulnerabilities that arise during tumor evolution represent an attractive intervention target class. However, the frequency and diversity of somatic lesions detected among lung tumors can confound efforts to identify these targets. To confront this challenge, we have applied parallel screening of chemical and genetic perturbations within a panel of molecularly annotated NSCLC lines to identify intervention opportunities tightly linked to molecular response indicators predictive of target sensitivity. Anchoring this analysis on a matched tumor/normal cell model from a lung adenocarcinoma patient identified three distinct target/response-indicator pairings that are represented with significant frequencies (6%-16%) in the patient population. These include NLRP3 mutation/inflammasome activation-dependent FLIP addiction, co-occurring KRAS and LKB1 mutation-driven COPI addiction, and selective sensitivity to a synthetic indolotriazine that is specified by a seven-gene expression signature. Target efficacies were validated in vivo, and mechanism-of-action studies informed generalizable principles underpinning cancer cell biology.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Ensaios de Seleção de Medicamentos Antitumorais , Indóis/farmacologia , Neoplasias Pulmonares/metabolismo , Triazinas/farmacologia , Animais , Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Proteínas de Transporte , Linhagem Celular Tumoral , Proteína Coatomer/metabolismo , Feminino , Genes ras , Xenoenxertos , Humanos , Neoplasias Pulmonares/patologia , Lisossomos/metabolismo , Camundongos , Terapia de Alvo Molecular , Proteína 3 que Contém Domínio de Pirina da Família NLR , Transplante de Neoplasias , Fosforilação Oxidativa
5.
Genes Dev ; 33(17-18): 1236-1251, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31416966

RESUMO

Tumors display increased uptake and processing of nutrients to fulfill the demands of rapidly proliferating cancer cells. Seminal studies have shown that the proto-oncogene MYC promotes metabolic reprogramming by altering glutamine uptake and metabolism in cancer cells. How MYC regulates the metabolism of other amino acids in cancer is not fully understood. Using high-performance liquid chromatography (HPLC)-tandem mass spectrometry (LC-MS/MS), we found that MYC increased intracellular levels of tryptophan and tryptophan metabolites in the kynurenine pathway. MYC induced the expression of the tryptophan transporters SLC7A5 and SLC1A5 and the enzyme arylformamidase (AFMID), involved in the conversion of tryptophan into kynurenine. SLC7A5, SLC1A5, and AFMID were elevated in colon cancer cells and tissues, and kynurenine was significantly greater in tumor samples than in the respective adjacent normal tissue from patients with colon cancer. Compared with normal human colonic epithelial cells, colon cancer cells were more sensitive to the depletion of tryptophan. Blocking enzymes in the kynurenine pathway caused preferential death of established colon cancer cells and transformed colonic organoids. We found that only kynurenine and no other tryptophan metabolite promotes the nuclear translocation of the transcription factor aryl hydrocarbon receptor (AHR). Blocking the interaction between AHR and kynurenine with CH223191 reduced the proliferation of colon cancer cells. Therefore, we propose that limiting cellular kynurenine or its downstream targets could present a new strategy to reduce the proliferation of MYC-dependent cancer cells.


Assuntos
Neoplasias do Colo/fisiopatologia , Cinurenina/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Triptofano/metabolismo , Sistema ASC de Transporte de Aminoácidos/genética , Antineoplásicos/farmacologia , Arilformamidase/genética , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Humanos , Indóis/farmacologia , Cinurenina/genética , Transportador 1 de Aminoácidos Neutros Grandes/genética , Antígenos de Histocompatibilidade Menor/genética , Oximas/farmacologia , Proto-Oncogene Mas , Sulfonamidas/farmacologia
6.
J Biol Chem ; 300(3): 105680, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38272230

RESUMO

Migration and invasion enhancer 1 (MIEN1) overexpression characterizes several cancers and facilitates cancer cell migration and invasion. Leveraging conserved immunoreceptor tyrosine-based activation motif and prenylation motifs within MIEN1, we identified potent anticancer peptides. Among them, bioactive peptides LA3IK and RP-7 induced pronounced transcriptomic and protein expression changes at sub-IC50 concentrations. The peptides effectively inhibited genes and proteins driving cancer cell migration, invasion, and epithelial-mesenchymal transition pathways, concurrently suppressing epidermal growth factor-induced nuclear factor kappa B nuclear translocation in metastatic breast cancer cells. Specifically, peptides targeted the same signal transduction pathway initiated by MIEN1. Molecular docking and CD spectra indicated the formation of MIEN1-peptide complexes. The third-positioned isoleucine in LA3IK and CVIL motif in RP-7 were crucial for inhibiting breast cancer cell migration. This is evident from the limited migration inhibition observed when MDA-MB-231 cells were treated with scrambled peptides LA3IK SCR and RP-7 SCR. Additionally, LA3IK and RP-7 effectively suppressed tumor growth in an orthotopic breast cancer model. Notably, mice tolerated high intraperitoneal (ip) peptide doses of 90 mg/Kg well, surpassing significantly lower doses of 5 mg/Kg intravenously (iv) and 30 mg/Kg intraperitoneally (ip) used in both in vivo pharmacokinetic studies and orthotopic mouse model assays. D-isomers of LA3IK and RP-7 showed enhanced anticancer activity compared to their L-isomers. D-LA3IK remained stable in mouse plasma for 24 h with 75% remaining, exhibiting superior pharmacokinetic properties over D/L-RP-7. In summary, our findings mark the first report of short peptides based on MIEN1 protein sequence capable of inhibiting cancer signaling pathways, effectively impeding cancer progression both in vitro and in vivo.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular , Proteínas de Neoplasias , Animais , Camundongos , Movimento Celular/genética , Proliferação de Células , Transição Epitelial-Mesenquimal , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Simulação de Acoplamento Molecular , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Transdução de Sinais , Humanos , Linhagem Celular , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia
7.
Cell ; 142(1): 39-51, 2010 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-20603013

RESUMO

An in vivo screen was performed in search of chemicals capable of enhancing neuron formation in the hippocampus of adult mice. Eight of 1000 small molecules tested enhanced neuron formation in the subgranular zone of the dentate gyrus. Among these was an aminopropyl carbazole, designated P7C3, endowed with favorable pharmacological properties. In vivo studies gave evidence that P7C3 exerts its proneurogenic activity by protecting newborn neurons from apoptosis. Mice missing the gene encoding neuronal PAS domain protein 3 (NPAS3) are devoid of hippocampal neurogenesis and display malformation and electrophysiological dysfunction of the dentate gyrus. Prolonged administration of P7C3 to npas3(-/-) mice corrected these deficits by normalizing levels of apoptosis of newborn hippocampal neurons. Prolonged administration of P7C3 to aged rats also enhanced neurogenesis in the dentate gyrus, impeded neuron death, and preserved cognitive capacity as a function of terminal aging. PAPERCLIP:


Assuntos
Carbazóis/farmacologia , Avaliação Pré-Clínica de Medicamentos , Neurogênese/efeitos dos fármacos , Neurônios/citologia , Fármacos Neuroprotetores/farmacologia , Envelhecimento/efeitos dos fármacos , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Carbazóis/química , Cognição/efeitos dos fármacos , Giro Denteado/citologia , Giro Denteado/fisiologia , Feminino , Hipocampo/citologia , Hipocampo/efeitos dos fármacos , Hipocampo/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Membranas Mitocondriais/efeitos dos fármacos , Membranas Mitocondriais/metabolismo , Fármacos Neuroprotetores/química , Ratos
8.
Nature ; 567(7748): 341-346, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30842654

RESUMO

Cancer-specific inhibitors that reflect the unique metabolic needs of cancer cells are rare. Here we describe Gboxin, a small molecule that specifically inhibits the growth of primary mouse and human glioblastoma cells but not that of mouse embryonic fibroblasts or neonatal astrocytes. Gboxin rapidly and irreversibly compromises oxygen consumption in glioblastoma cells. Gboxin relies on its positive charge to associate with mitochondrial oxidative phosphorylation complexes in a manner that is dependent on the proton gradient of the inner mitochondrial membrane, and it inhibits the activity of F0F1 ATP synthase. Gboxin-resistant cells require a functional mitochondrial permeability transition pore that regulates pH and thus impedes the accumulation of Gboxin in the mitochondrial matrix. Administration of a metabolically stable Gboxin analogue inhibits glioblastoma allografts and patient-derived xenografts. Gboxin toxicity extends to established human cancer cell lines of diverse organ origin, and shows that the increased proton gradient and pH in cancer cell mitochondria is a mode of action that can be targeted in the development of antitumour reagents.


Assuntos
Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Fosforilação Oxidativa/efeitos dos fármacos , Aloenxertos , Animais , Astrócitos/citologia , Astrócitos/efeitos dos fármacos , Linhagem Celular Tumoral , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Camundongos , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Membranas Mitocondriais/efeitos dos fármacos , Membranas Mitocondriais/enzimologia , Membranas Mitocondriais/metabolismo , Poro de Transição de Permeabilidade Mitocondrial , Transplante de Neoplasias , Especificidade de Órgãos , Força Próton-Motriz/efeitos dos fármacos , ATPases Translocadoras de Prótons/antagonistas & inibidores , ATPases Translocadoras de Prótons/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Artigo em Inglês | MEDLINE | ID: mdl-38775726

RESUMO

Oral contraceptive pills are used by approximately 250 million women worldwide, however a clear understanding of the concentrations of endogenous and exogenous hormones across a 28-day oral contraceptive pill pack is not well described. In our study of 16 female participants taking various monophasic oral contraceptive pills, we found significant fluctuations in endogenous and exogenous hormone levels throughout the pill cycle, challenging the previous assumption of hormonal stability in oral contraceptive users. The results from this study have wide ranging implications for research and treatment in women's health including: considerations in research design and interpretation for studies including women taking oral contraceptives, the potential for more precise and personalized methods of dosing to reduce unwanted side effects and adverse events, and the potential treatment of a variety of disorders ranging from musculoskeletal to neurological with exogenous hormones.

10.
Bioorg Med Chem Lett ; 99: 129624, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38272190

RESUMO

A structurally novel class of benzo- or pyrido-fused 1,3-dihydro-2H-imidazole-2-imines was designed and evaluated in an inositol phosphate accumulation assay for Gq signaling to measure agonistic activation of the orexin receptor type 2 (OX2R). These compounds were synthesized in 4-9 steps overall from readily available starting materials. Analogs that contain a stereogenic methyl or cyclopropyl substituent at the benzylic center, and a correctly configured alkyl ether, alkoxyalkyl ether, cyanoalkyl ether, or α-hydroxyacetamido substituted homobenzylic sidechain were identified as the most potent activators of OX2R coupled Gq signaling. Our results also indicate that agonistic activity was stereospecific at both the benzylic and homobenzylic stereogenic centra. We identified methoxyethoxy-substituted pyrido-fused dihydroimidazolimine analog 63c containing a stereogenic benzylic methyl group was the most potent agonist, registering a respectable EC50 of 339 nM and a maximal response (Emax) of 96 % in this assay. In vivo pharmacokinetic analysis indicated good brain exposure for several analogs. Our combined results provide important information towards a structurally novel class of orexin receptor agonists distinct from current chemotypes.


Assuntos
Imidazóis , Iminas , Receptores de Orexina/agonistas , Iminas/farmacologia , Imidazóis/farmacologia , Piridinas , Éteres
11.
J Sleep Res ; 32(4): e13839, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36808670

RESUMO

The sleep disorder narcolepsy, a hypocretin deficiency disorder thought to be due to degeneration of hypothalamic hypocretin/orexin neurons, is currently treated symptomatically. We evaluated the efficacy of two small molecule hypocretin/orexin receptor-2 (HCRTR2) agonists in narcoleptic male orexin/tTA; TetO-DTA mice. TAK-925 (1-10 mg/kg, s.c.) and ARN-776 (1-10 mg/kg, i.p.) were injected 15 min before dark onset in a repeated measures design. EEG, EMG, subcutaneous temperature (Tsc ) and activity were recorded by telemetry; recordings for the first 6 h of the dark period were scored for sleep/wake and cataplexy. At all doses tested, TAK-925 and ARN-776 caused continuous wakefulness and eliminated sleep for the first hour. Both TAK-925 and ARN-776 caused dose-related delays in NREM sleep onset. All doses of TAK-925 and all but the lowest dose of ARN-776 eliminated cataplexy during the first hour after treatment; the anti-cataplectic effect of TAK-925 persisted into the second hour for the highest dose. TAK-925 and ARN-776 also reduced the cumulative amount of cataplexy during the 6 h post-dosing period. The acute increase in wakefulness produced by both HCRTR2 agonists was characterised by increased spectral power in the gamma EEG band. Although neither compound provoked a NREM sleep rebound, both compounds affected NREM EEG during the second hour post-dosing. TAK-925 and ARN-776 also increased gross motor activity, running wheel activity, and Tsc , suggesting that the wake-promoting and sleep-suppressing activities of these compounds could be a consequence of hyperactivity. Nonetheless, the anti-cataplectic activity of TAK-925 and ARN-776 is encouraging for the development of HCRTR2 agonists.


Assuntos
Cataplexia , Narcolepsia , Animais , Masculino , Camundongos , Cataplexia/tratamento farmacológico , Narcolepsia/tratamento farmacológico , Receptores de Orexina/uso terapêutico , Orexinas , Sono/fisiologia , Vigília/fisiologia
12.
PLoS Genet ; 16(11): e1009117, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33201894

RESUMO

Glioblastoma is the most common and aggressive type of cancer in the brain; its poor prognosis is often marked by reoccurrence due to resistance to the chemotherapeutic agent temozolomide, which is triggered by an increase in the expression of DNA repair enzymes such as MGMT. The poor prognosis and limited therapeutic options led to studies targeted at understanding specific vulnerabilities of glioblastoma cells. Metabolic adaptations leading to increased synthesis of nucleotides by de novo biosynthesis pathways are emerging as key alterations driving glioblastoma growth. In this study, we show that enzymes necessary for the de novo biosynthesis of pyrimidines, DHODH and UMPS, are elevated in high grade gliomas and in glioblastoma cell lines. We demonstrate that DHODH's activity is necessary to maintain ribosomal DNA transcription (rDNA). Pharmacological inhibition of DHODH with the specific inhibitors brequinar or ML390 effectively depleted the pool of pyrimidines in glioblastoma cells grown in vitro and in vivo and impaired rDNA transcription, leading to nucleolar stress. Nucleolar stress was visualized by the aberrant redistribution of the transcription factor UBF and the nucleolar organizer nucleophosmin 1 (NPM1), as well as the stabilization of the transcription factor p53. Moreover, DHODH inhibition decreased the proliferation of glioblastoma cells, including temozolomide-resistant cells. Importantly, the addition of exogenous uridine, which reconstitutes the cellular pool of pyrimidine by the salvage pathway, to the culture media recovered the impaired rDNA transcription, nucleolar morphology, p53 levels, and proliferation of glioblastoma cells caused by the DHODH inhibitors. Our in vivo data indicate that while inhibition of DHODH caused a dramatic reduction in pyrimidines in tumor cells, it did not affect the overall pyrimidine levels in normal brain and liver tissues, suggesting that pyrimidine production by the salvage pathway may play an important role in maintaining these nucleotides in normal cells. Our study demonstrates that glioblastoma cells heavily rely on the de novo pyrimidine biosynthesis pathway to generate ribosomal RNA (rRNA) and thus, we identified an approach to inhibit ribosome production and consequently the proliferation of glioblastoma cells through the specific inhibition of the de novo pyrimidine biosynthesis pathway.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Nucléolo Celular/efeitos dos fármacos , Glioblastoma/tratamento farmacológico , Pirimidinas/biossíntese , Animais , Antineoplásicos/uso terapêutico , Compostos de Bifenilo/farmacologia , Compostos de Bifenilo/uso terapêutico , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Nucléolo Celular/metabolismo , Di-Hidro-Orotato Desidrogenase , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Glioblastoma/patologia , Humanos , Camundongos , Complexos Multienzimáticos/antagonistas & inibidores , Complexos Multienzimáticos/metabolismo , Nucleofosmina , Orotato Fosforribosiltransferase/antagonistas & inibidores , Orotato Fosforribosiltransferase/metabolismo , Orotidina-5'-Fosfato Descarboxilase/antagonistas & inibidores , Orotidina-5'-Fosfato Descarboxilase/metabolismo , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/antagonistas & inibidores , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/metabolismo , RNA Ribossômico/biossíntese , Ribossomos/efeitos dos fármacos , Ribossomos/metabolismo , Estresse Fisiológico/efeitos dos fármacos , Transcrição Gênica/efeitos dos fármacos , Proteína Supressora de Tumor p53/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Pediatr Blood Cancer ; 67(12): e28639, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32975370

RESUMO

BACKGROUND: Malignant peripheral nerve sheath tumor (MPNST) is an aggressive form of soft-tissue sarcoma (STS) in children. Despite intensive therapy, relatively few children with metastatic and unresectable disease survive beyond three years. RAS pathway activation is common in MPNST, suggesting MEK pathway inhibition as a targeted therapy, but the impact on clinical outcome has been small to date. PROCEDURE: We conducted preclinical pharmacokinetic (PK) and pharmacodynamic studies of two MEK inhibitors, trametinib and selumetinib, in two MPNST models and analyzed tumors for intratumor drug levels. We then investigated 3'-deoxy-3'-[18 F]fluorothymidine (18 F-FLT) PET imaging followed by 18 F-FDG PET/CT imaging of MPNST xenografts coupled to short-term or longer-term treatment with selumetinib focusing on PET-based imaging as a biomarker of MEK inhibition. RESULTS: Trametinib decreased pERK expression in MPNST xenografts but did not prolong survival or decrease Ki67 expression. In contrast, selumetinib prolonged survival of animals bearing MPNST xenografts, and this correlated with decreased pERK and Ki67 staining. PK studies revealed a significantly higher fraction of unbound selumetinib within a responsive MPNST xenograft model. Thymidine uptake, assessed by 18 F-FLT PET/CT, positively correlated with Ki67 expression in different xenograft models and in response to selumetinib. CONCLUSION: The ability of MEK inhibitors to control MPNST growth cannot simply be predicted by serum drug levels or drug-induced changes in pERK expression. Tumor cell proliferation assessed by 18 F-FLT PET imaging might be useful as an early response marker to targeted therapies, including MEK inhibition, where a primary effect is cell-cycle arrest.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neurofibrossarcoma/patologia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Proteínas ras/antagonistas & inibidores , Animais , Apoptose , Benzimidazóis/administração & dosagem , Proliferação de Células , Fluordesoxiglucose F18/farmacocinética , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Neurofibrossarcoma/diagnóstico por imagem , Neurofibrossarcoma/tratamento farmacológico , Neurofibrossarcoma/metabolismo , Piridonas/administração & dosagem , Pirimidinonas/administração & dosagem , Compostos Radiofarmacêuticos/farmacocinética , Distribuição Tecidual , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Int J Hyperthermia ; 37(1): 1052-1059, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32892667

RESUMO

PURPOSE: When doxorubicin (DOX) is administered via lyso-thermosensitive liposomes (LTLD), mild hyperthermia enhances localized delivery to heated vs. unheated tumors. The optimal LTLD dose and the impact of different doses on systemic drug distribution are unknown.Materials and methods: In this study, we evaluated local and systemic DOX delivery with three LTLD doses (0.1, 0.5, and 2.5 mg/kg) in a Vx2 rabbit tumor model. Temporally and spatially accurate controlled hyperthermia was achieved using a clinical MR-HIFU system for the intended heating duration (40 min).Results: DOX concentration in tissues delivered from LTLD combined with MR-HIFU mild hyperthermia are dose-dependent, including heated/unheated tumor, heart, and other healthy organs. Higher DOX accumulation and tumor-to-heart drug concentration ratio, defined as the ratio of DOX delivered into the tumor vs the heart, were observed in heated tumors compared to unheated tumors in all three tested doses. The DOX uptake efficiency for each mg/kg of LTLD injected IV of heated tumor was significantly higher than that of unheated tumor and heart within the tested dose range (0.1-2.5 mg/kg). The DOX uptake for the heart linearly scaled up as a function of dose while that for the heated tumor showed some evidence of saturation at the high dose of 2.5 mg/kg.Conclusions: These results provide guidance on clinical protocol design of hyperthermia-triggered drug delivery.


Assuntos
Hipertermia Induzida , Neoplasias , Animais , Antibióticos Antineoplásicos/uso terapêutico , Doxorrubicina/uso terapêutico , Sistemas de Liberação de Medicamentos , Hipertermia , Lipossomos , Neoplasias/terapia , Coelhos
15.
Proc Natl Acad Sci U S A ; 114(7): 1649-1654, 2017 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-28143939

RESUMO

The secreted Wnt signaling molecules are essential to the coordination of cell-fate decision making in multicellular organisms. In adult animals, the secreted Wnt proteins are critical for tissue regeneration and frequently contribute to cancer. Small molecules that disable the Wnt acyltransferase Porcupine (Porcn) are candidate anticancer agents in clinical testing. Here we have systematically assessed the effects of the Porcn inhibitor (WNT-974) on the regeneration of several tissue types to identify potentially unwanted chemical effects that could limit the therapeutic utility of such agents. An unanticipated observation from these studies is proregenerative responses in heart muscle induced by systemic chemical suppression of Wnt signaling. Using in vitro cultures of several cell types found in the heart, we delineate the Wnt signaling apparatus supporting an antiregenerative transcriptional program that includes a subunit of the nonfibrillar collagen VI. Similar to observations seen in animals exposed to WNT-974, deletion of the collagen VI subunit, COL6A1, has been shown to decrease aberrant remodeling and fibrosis in infarcted heart tissue. We demonstrate that WNT-974 can improve the recovery of heart function after left anterior descending coronary artery ligation by mitigating adverse remodeling of infarcted tissue. Injured heart tissue exposed to WNT-974 exhibits decreased scarring and reduced Col6 production. Our findings support the development of Porcn inhibitors as antifibrotic agents that could be exploited to promote heart repair following injury.


Assuntos
Aciltransferases/antagonistas & inibidores , Remodelamento Atrial/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Proteínas de Membrana/antagonistas & inibidores , Infarto do Miocárdio/prevenção & controle , Aciltransferases/genética , Aciltransferases/metabolismo , Animais , Remodelamento Atrial/genética , Células Cultivadas , Colágeno Tipo VI/genética , Colágeno Tipo VI/metabolismo , Inibidores Enzimáticos/química , Expressão Gênica/efeitos dos fármacos , Células HEK293 , Humanos , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos Endogâmicos C57BL , Estrutura Molecular , Infarto do Miocárdio/genética , Infarto do Miocárdio/fisiopatologia , Pirazinas/química , Pirazinas/farmacologia , Piridinas/química , Piridinas/farmacologia , Regeneração/efeitos dos fármacos , Regeneração/genética , Via de Sinalização Wnt/efeitos dos fármacos , Via de Sinalização Wnt/genética
16.
J Med Internet Res ; 22(3): e12689, 2020 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-32209536

RESUMO

BACKGROUND: Measuring patient-reported outcomes (PROs) requires an individual's perspective on their symptoms, functional status, and quality of life. Digital health enables remote electronic PRO (ePRO) assessments as a clinical decision support tool to facilitate meaningful provider interactions and personalized treatment. OBJECTIVE: This study explored the feasibility and acceptability of collecting ePROs using validated health-related quality of life (HRQoL) questionnaires for prostate cancer. METHODS: Using Apple ResearchKit software, the Strength Through Insight app was created with content from validated HRQoL tools 26-item Expanded Prostate Cancer Index Composite (EPIC) or EPIC for Clinical Practice and 8-item Functional Assessment of Cancer Therapy Advanced Prostate Symptom Index. In a single-arm pilot study with patients receiving prostate cancer treatment at Thomas Jefferson University Hospital and affiliates, participants were recruited, and instructed to download Strength Through Insight and complete ePROs once a week over 12 weeks. A mixed methods approach, including qualitative pre- and poststudy interviews, was used to evaluate the feasibility and acceptability of Strength Through Insight for the collection and care management of cancer treatment. RESULTS: Thirty patients consented to the study; 1 patient failed to complete any of the questionnaires and was left out of the analysis of the intervention. Moreover, 86% (25/29) reached satisfactory questionnaire completion (defined as completion of 60% of weekly questions over 12 weeks). The lower bound of the exact one-sided 95% CI was 71%, exceeding the 70% feasibility threshold. Most participants self-identified with having a high digital literacy level (defined as the ability to use, understand, evaluate, and analyze information from multiple formats from a variety of digital sources), and only a few participants identified with having a low digital literacy level (defined as only having the ability to gather information on the Web). Interviews were thematically analyzed to reveal the following: (1) value of emotional support and wellness in cancer treatment, (2) rise of social patient advocacy in online patient communities and networks, (3) patient concerns over privacy, and (4) desire for personalized engagement tools. CONCLUSIONS: Strength Through Insight was demonstrated as a feasible and acceptable method of data collection for ePROs. A high compliance rate confirmed the app as a reliable tool for patients with localized and advanced prostate cancer. Nearly all participants reported that using the smartphone app is easier than or equivalent to the traditional paper-and-pen approach, providing evidence of acceptability and support for the use of remote PRO monitoring. This study expands on current research involving the value of digital health, as a social and behavioral science, augmented with technology, can begin to contribute to population health management, as it shapes psychographic segmentation by demographic, socioeconomic, health condition, or behavioral factors to group patients by their distinct personalities and motivations, which influence their choices. TRIAL REGISTRATION: ClinicalTrials.gov NC03197948; http://clinicaltrials.gov/ct2/show/NC03197948.


Assuntos
Medidas de Resultados Relatados pelo Paciente , Neoplasias da Próstata/epidemiologia , Qualidade de Vida/psicologia , Telemedicina/métodos , Idoso , Estudos de Viabilidade , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Inquéritos e Questionários
17.
Int J Hyperthermia ; 36(1): 196-203, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30541350

RESUMO

Thermosensitive liposomal doxorubicin (LTSL-Dox) combined with mild hyperthermia enhances the localized delivery of doxorubicin (Dox) within a heated region. The optimal heating duration and the impact of extended heating on systemic drug distribution are unknown. Here we evaluated local and systemic Dox delivery with two different mild hyperthermia durations (42 °C for 10 or 40 minutes) in a Vx2 rabbit tumor model. We hypothesized that longer duration of hyperthermia would increase Dox concentration in heated tumors without increasing systemic exposure. Temporally and spatially accurate controlled hyperthermia was achieved using a clinical MR-HIFU system for the prescribed heating durations. Forty-minutes of heating resulted in a nearly 6-fold increase in doxorubicin concentration in heated vs unheated tumors in the same animals. Therapeutic ratio, defined as the ratio of Dox delivered into the heated tumor vs the heart, increased from 1.9-fold with 10 minutes heating to 4.4-fold with 40 minutes heating. MR-HIFU can be used to guide, deliver and monitor mild hyperthermia of a Vx2 tumor model in a rabbit model, and an increased duration of heating leads to higher Dox deposition from LTSL-Dox in a target tumor without a concomitant increase in systemic exposure. Results from this preclinical study can be used to help establish clinical treatment protocols for hyperthermia mediated drug delivery.


Assuntos
Doxorrubicina/análogos & derivados , Doxorrubicina/uso terapêutico , Calefação/métodos , Ablação por Ultrassom Focalizado de Alta Intensidade/métodos , Imageamento por Ressonância Magnética/métodos , Animais , Doxorrubicina/farmacologia , Feminino , Humanos , Polietilenoglicóis/farmacologia , Polietilenoglicóis/uso terapêutico , Coelhos
18.
Cancer ; 124(3): 499-506, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-29072790

RESUMO

BACKGROUND: Patients with prostate cancer receiving androgen deprivation therapy (ADT) are at risk of sleep disturbance; however, to the authors' knowledge, the mechanisms by which ADT may affect sleep are not well understood. The current study compared objective and subjective sleep disturbance in ADT recipients and controls and examined whether sleep disturbance in ADT recipients is attributable to the influence of ADT on hot flashes and nocturia. METHODS: Patients with prostate cancer were assessed before or within 1 month after the initiation of ADT as well as 6 months and 12 months later (78 patients). Patients with prostate cancer were treated with prostatectomy only (99 patients) and men with no history of cancer (108 men) were assessed at similar intervals. Participants self-reported their sleep disturbance (Insomnia Severity Index) and interference from hot flashes (Hot Flash Related Daily Interference Scale). One hundred participants also wore actigraphs for 3 days at the 6-month assessment to measure objective sleep disturbance and reported their nocturia frequency. RESULTS: ADT recipients reported worse sleep disturbance, higher rates of clinically significant sleep disturbance, and greater hot flash interference than controls (Ps≤.03). In cross-sectional analyses among those with actigraphy data, ADT recipients had greater objective sleep disturbance and more episodes of nocturia (Ps<.01). Cross-sectional mediation analyses demonstrated that the association between ADT and objectively and subjectively measured sleep disturbance was partly attributable to nocturia and hot flashes (Ps<.05). CONCLUSIONS: The results of the current study suggest that the association between ADT and sleep may be partly explained by nocturia and hot flash interference. Future studies should examine behavioral and pharmacologic interventions to address these symptoms among ADT recipients. Cancer 2018;124:499-506. © 2017 American Cancer Society.


Assuntos
Antagonistas de Androgênios/efeitos adversos , Fogachos/epidemiologia , Noctúria/epidemiologia , Neoplasias da Próstata/tratamento farmacológico , Transtornos do Sono-Vigília/epidemiologia , Idoso , Estudos Transversais , Humanos , Masculino , Pessoa de Meia-Idade , Prostatectomia
19.
Nat Chem Biol ; 12(4): 218-25, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26829472

RESUMO

A hallmark of targeted cancer therapies is selective toxicity among cancer cell lines. We evaluated results from a viability screen of over 200,000 small molecules to identify two chemical series, oxalamides and benzothiazoles, that were selectively toxic at low nanomolar concentrations to the same 4 of 12 human lung cancer cell lines. Sensitive cell lines expressed cytochrome P450 (CYP) 4F11, which metabolized the compounds into irreversible inhibitors of stearoyl CoA desaturase (SCD). SCD is recognized as a promising biological target in cancer and metabolic disease. However, SCD is essential to sebocytes, and accordingly SCD inhibitors cause skin toxicity. Mouse sebocytes did not activate the benzothiazoles or oxalamides into SCD inhibitors, providing a therapeutic window for inhibiting SCD in vivo. We thus offer a strategy to target SCD in cancer by taking advantage of high CYP expression in a subset of tumors.


Assuntos
Antineoplásicos/farmacologia , Benzotiazóis/farmacologia , Descoberta de Drogas/métodos , Neoplasias Pulmonares/enzimologia , Ácido Oxâmico/análogos & derivados , Estearoil-CoA Dessaturase/antagonistas & inibidores , Animais , Antineoplásicos/farmacocinética , Antineoplásicos/uso terapêutico , Antineoplásicos/toxicidade , Benzotiazóis/farmacocinética , Benzotiazóis/uso terapêutico , Benzotiazóis/toxicidade , Linhagem Celular Tumoral , Sistema Enzimático do Citocromo P-450/metabolismo , Família 4 do Citocromo P450 , Feminino , Humanos , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Camundongos SCID , Estrutura Molecular , Terapia de Alvo Molecular , Ácido Oxâmico/farmacocinética , Ácido Oxâmico/farmacologia , Ácido Oxâmico/uso terapêutico , Ácido Oxâmico/toxicidade , Ligação Proteica , Glândulas Sebáceas/efeitos dos fármacos , Glândulas Sebáceas/enzimologia , Glândulas Sebáceas/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
20.
J Neurooncol ; 140(2): 421-426, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30088191

RESUMO

BACKGROUND: Glioblastoma predominantly occurs in the 6th and 7th decades of life. The optimal treatment paradigm for elderly patients is not well established. We sampled current worldwide management strategies for elderly patients with newly diagnosed glioblastoma. METHODS: A web-based survey was developed and distributed to 168 radiation oncologists, neuro-oncologists and neurosurgeons identified through the United Council for Neurologic Subspecialties and the CNS committees for North American, European and Asian Organizations. Questions addressed treatment recommendations in order to determine whether management consensus exists in this patient subset. RESULTS: There were 68 (40%) respondents. Across respondents, the most important factors directing treatment were KPS (94%) and MGMT methylation status (71%). Only 37% of respondents strictly factor in age when making treatment recommendations with 59% defining elderly as greater than 70 years-old. The most common treatment recommendations for MGMT-methylated elderly patients with KPS > 70 were as follows: standard chemoRT (49%), short course chemoRT (39%), and temozolomide alone (30%). The most common treatment recommendations for MGMT-unmethylated patients with KPS > 70 were as follows: short course RT alone (51%), standard chemoRT (38%), and short course chemoRT (28%). Treatment recommendations for patients with KPS < 50 were short course RT alone (40%), best supportive care (57%), or TMZ alone (17%). Individuals practicing in North America were significantly more likely to recommend standard chemoradiation for patients compared to their European counterparts. CONCLUSION: Worldwide treatment recommendations for elderly patients with newly diagnosed GBM vary widely. Further randomized studies are needed to elucidate the optimal treatment strategy for this subset of patients.


Assuntos
Neoplasias Encefálicas/terapia , Glioblastoma/terapia , Guias de Prática Clínica como Assunto , Idoso , Protocolos Antineoplásicos , Ensaios Clínicos como Assunto , Consenso , Gerenciamento Clínico , Humanos , Internacionalidade , Padrões de Prática Médica , Inquéritos e Questionários
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