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1.
Br J Cancer ; 130(8): 1377-1387, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38396173

RESUMO

BACKGROUND/OBJECTIVE: To explore the anti-tumour activity of combining AKT inhibition and docetaxel in PTEN protein null and WT prostate tumours. METHODS: Mechanisms associated with docetaxel capivasertib treatment activity in prostate cancer were examined using a panel of in vivo tumour models and cell lines. RESULTS: Combining docetaxel and capivasertib had increased activity in PTEN null and WT prostate tumour models in vivo. In vitro short-term docetaxel treatment caused cell cycle arrest in the majority of cells. However, a sub-population of docetaxel-persister cells did not undergo G2/M arrest but upregulated phosphorylation of PI3K/AKT pathway effectors GSK3ß, p70S6K, 4E-BP1, but to a lesser extent AKT. In vivo acute docetaxel treatment induced p70S6K and 4E-BP1 phosphorylation. Treating PTEN null and WT docetaxel-persister cells with capivasertib reduced PI3K/AKT pathway activation and cell cycle progression. In vitro and in vivo it reduced proliferation and increased apoptosis or DNA damage though effects were more marked in PTEN null cells. Docetaxel-persister cells were partly reliant on GSK3ß as a GSK3ß inhibitor AZD2858 reversed capivasertib-induced apoptosis and DNA damage. CONCLUSION: Capivasertib can enhance anti-tumour effects of docetaxel by targeting residual docetaxel-persister cells, independent of PTEN status, to induce apoptosis and DNA damage in part through GSK3ß.


Assuntos
Neoplasias da Próstata , Proteínas Proto-Oncogênicas c-akt , Pirimidinas , Pirróis , Masculino , Humanos , Docetaxel/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Proteínas Quinases S6 Ribossômicas 70-kDa/farmacologia , Transdução de Sinais , Apoptose , Fosfatidilinositol 3-Quinases/metabolismo , Glicogênio Sintase Quinase 3 beta , Linhagem Celular Tumoral , Pontos de Checagem da Fase G2 do Ciclo Celular , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/metabolismo , PTEN Fosfo-Hidrolase/metabolismo
2.
Biophys J ; 121(22): 4280-4298, 2022 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-36230002

RESUMO

Mutations in the TP53 gene are common in cancer with the R248Q missense mutation conferring an increased propensity to aggregate. Previous p53 aggregation studies showed that, at micromolar concentrations, protein unfolding to produce aggregation-prone species is the rate-determining step. Here we show that, at physiological concentrations, aggregation kinetics of insect cell-derived full-length wild-type p53 and p53R248Q are determined by a nucleation-growth model, rather than formation of aggregation-prone monomeric species. Self-seeding, but not cross-seeding, increases aggregation rate, confirming the aggregation process as rate determining. p53R248Q displays enhanced aggregation propensity due to decreased solubility and increased aggregation rate, forming greater numbers of larger amorphous aggregates that disrupt lipid bilayers and invokes an inflammatory response. These results suggest that p53 aggregation can occur under physiological conditions, a rate enhanced by R248Q mutation, and that aggregates formed can cause membrane damage and inflammation that may influence tumorigenesis.


Assuntos
Genes p53 , Proteína Supressora de Tumor p53 , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Cinética , Mutação , Desdobramento de Proteína , Agregados Proteicos
3.
J Pathol ; 237(2): 152-65, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25965974

RESUMO

Metabolic reprogramming in cancer enhances macromolecule biosynthesis and supports cell survival. Oncogenic drivers affect metabolism by altering distinct metabolic processes and render cancer cells sensitive to perturbations of the metabolic network. This study aimed to identify selective metabolic dependencies in breast cancer by investigating 17 breast cancer cells lines representative of the genetic diversity of the disease. Using a functional screen, we demonstrate here that monocarboxylate transporter 4 (MCT4) is an important regulator of breast cancer cell survival. MCT4 supports pH maintenance, lactate secretion and non-oxidative glucose metabolism in breast cancer cells. Moreover, MCT4 depletion caused an increased dependence of cancer cells on mitochondrial respiration and glutamine metabolism. MCT4 depletion reduced the ability of breast cancer cells to grow in a three-dimensional (3D) matrix or as multilayered spheroids. Moreover, MCT4 expression is regulated by the PI3K-Akt signalling pathway and highly expressed in HER2-positive breast cancers. These results suggest that MCT4 is a potential therapeutic target in defined breast cancer subtypes and reveal novel avenues for combination treatment.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Metabolismo Energético , Transportadores de Ácidos Monocarboxílicos/metabolismo , Proteínas Musculares/metabolismo , Animais , Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Proliferação de Células , Sobrevivência Celular , Técnicas de Cocultura , Feminino , Regulação Neoplásica da Expressão Gênica , Glucose/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Ácido Láctico/metabolismo , Células MCF-7 , Camundongos Nus , Transportadores de Ácidos Monocarboxílicos/genética , Proteínas Musculares/genética , Fosfatidilinositol 3-Quinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Interferência de RNA , Receptor ErbB-2/metabolismo , Transdução de Sinais , Esferoides Celulares , Fatores de Tempo , Transfecção , Carga Tumoral
4.
Sci Signal ; 17(825): eadf2670, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38412255

RESUMO

More than 50% of human tumors display hyperactivation of the serine/threonine kinase AKT. Despite evidence of clinical efficacy, the therapeutic window of the current generation of AKT inhibitors could be improved. Here, we report the development of a second-generation AKT degrader, INY-05-040, which outperformed catalytic AKT inhibition with respect to cellular suppression of AKT-dependent phenotypes in breast cancer cell lines. A growth inhibition screen with 288 cancer cell lines confirmed that INY-05-040 had a substantially higher potency than our first-generation AKT degrader (INY-03-041), with both compounds outperforming catalytic AKT inhibition by GDC-0068. Using multiomic profiling and causal network integration in breast cancer cells, we demonstrated that the enhanced efficacy of INY-05-040 was associated with sustained suppression of AKT signaling, which was followed by induction of the stress mitogen-activated protein kinase (MAPK) c-Jun N-terminal kinase (JNK). Further integration of growth inhibition assays with publicly available transcriptomic, proteomic, and reverse phase protein array (RPPA) measurements established low basal JNK signaling as a biomarker for breast cancer sensitivity to AKT degradation. Together, our study presents a framework for mapping the network-wide signaling effects of therapeutically relevant compounds and identifies INY-05-040 as a potent pharmacological suppressor of AKT signaling.


Assuntos
Neoplasias da Mama , Proteínas Quinases Ativadas por Mitógeno , Humanos , Feminino , Proteínas Proto-Oncogênicas c-akt/metabolismo , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Apoptose , Mitógenos , Multiômica , Proteômica , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno , Proteínas Quinases JNK Ativadas por Mitógeno
5.
Neurooncol Adv ; 5(1): vdad120, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37885806

RESUMO

Background: Branched-chain aminotransferase 1 (BCAT1) has been proposed to drive proliferation and invasion of isocitrate dehydrogenase (IDH) wild-type glioblastoma cells. However, the Cancer Genome Atlas (TCGA) dataset shows considerable variation in the expression of this enzyme in glioblastoma. The aim of this study was to determine the role of BCAT1 in driving the proliferation and invasion of glioblastoma cells and xenografts that have widely differing levels of BCAT1 expression and the mechanism responsible. Methods: The activity of BCAT1 was modulated in IDH wild-type patient-derived glioblastoma cell lines, and in orthotopically implanted tumors derived from these cells, to examine the effects of BCAT1 expression on tumor phenotype. Results: In cells with constitutively high BCAT1 expression and a glycolytic metabolic phenotype, inducible shRNA knockdown of the enzyme resulted in reduced proliferation and invasion by increasing the concentration of α-ketoglutarate, leading to reduced DNA methylation, HIF-1α destabilization, and reduced expression of the transcription factor Forkhead box protein M1 (FOXM1). Conversely, overexpression of the enzyme increased HIF-1α expression and promoted proliferation and invasion. However, in cells with an oxidative phenotype and very low constitutive expression of BCAT1 increased expression of the enzyme had no effect on invasion and reduced cell proliferation. This occurred despite an increase in HIF-1α levels and could be explained by decreased TCA cycle flux. Conclusions: There is a wide variation in BCAT1 expression in glioblastoma and its role in proliferation and invasion is dependent on tumor subtype.

6.
NPJ Breast Cancer ; 9(1): 64, 2023 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-37543694

RESUMO

Combining the selective AKT inhibitor, capivasertib, and SERD, fulvestrant improved PFS in a Phase III clinical trial (CAPItello-291), treating HR+ breast cancer patients following aromatase inhibitors, with or without CDK4/6 inhibitors. However, clinical data suggests CDK4/6 treatment may reduce response to subsequent monotherapy endocrine treatment. To support understanding of trials such as CAPItello-291 and gain insight into this emerging population of patients, we explored how CDK4/6 inhibitor treatment influences ER+ breast tumour cell function and response to fulvestrant and capivasertib after CDK4/6 inhibitor treatment. In RB+, RB- T47D and MCF7 palbociclib-resistant cells ER pathway ER and Greb-1 expression were reduced versus naïve cells. PI3K-AKT pathway activation was also modified in RB+ cells, with capivasertib less effective at reducing pS6 in RB+ cells compared to parental cells. Expression profiling of parental versus palbociclib-resistant cells confirmed capivasertib, fulvestrant and the combination differentially impacted gene expression modulation in resistant cells, with different responses seen in T47D and MCF7 cells. Fulvestrant inhibition of ER-dependent genes was reduced. In resistant cells, the combination was less effective at reducing cell cycle genes, but a consistent reduction in cell fraction in S-phase was observed in naïve and resistant cells. Despite modified signalling responses, both RB+ and RB- resistant cells responded to combination treatment despite some reduction in relative efficacy and was effective in vivo in palbociclib-resistant PDX models. Collectively these findings demonstrate that simultaneous inhibition of AKT and ER signalling can be effective in models representing palbociclib resistance despite changes in pathway dependency.

7.
Cancer Res ; 83(23): 3989-4004, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37725704

RESUMO

Oral selective estrogen receptor degraders (SERD) could become the backbone of endocrine therapy (ET) for estrogen receptor-positive (ER+) breast cancer, as they achieve greater inhibition of ER-driven cancers than current ETs and overcome key resistance mechanisms. In this study, we evaluated the preclinical pharmacology and efficacy of the next-generation oral SERD camizestrant (AZD9833) and assessed ER-co-targeting strategies by combining camizestrant with CDK4/6 inhibitors (CDK4/6i) and PI3K/AKT/mTOR-targeted therapy in models of progression on CDK4/6i and/or ET. Camizestrant demonstrated robust and selective ER degradation, modulated ER-regulated gene expression, and induced complete ER antagonism and significant antiproliferation activity in ESR1 wild-type (ESR1wt) and mutant (ESR1m) breast cancer cell lines and patient-derived xenograft (PDX) models. Camizestrant also delivered strong antitumor activity in fulvestrant-resistant ESR1wt and ESR1m PDX models. Evaluation of camizestrant in combination with CDK4/6i (palbociclib or abemaciclib) in CDK4/6-naive and -resistant models, as well as in combination with PI3Kαi (alpelisib), mTORi (everolimus), or AKTi (capivasertib), indicated that camizestrant was active with CDK4/6i or PI3K/AKT/mTORi and that antitumor activity was further increased by the triple combination. The response was observed independently of PI3K pathway mutation status. Overall, camizestrant shows strong and broad antitumor activity in ER+ breast cancer as a monotherapy and when combined with CDK4/6i and PI3K/AKT/mTORi. SIGNIFICANCE: Camizestrant, a next-generation oral SERD, shows promise in preclinical models of ER+ breast cancer alone and in combination with CDK4/6 and PI3K/AKT/mTOR inhibitors to address endocrine resistance, a current barrier to treatment.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/patologia , Receptores de Estrogênio/metabolismo , Proteínas Proto-Oncogênicas c-akt , Fosfatidilinositol 3-Quinases/metabolismo , Antagonistas de Estrogênios , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Quinase 4 Dependente de Ciclina , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico
8.
J Biol Chem ; 285(48): 37170-7, 2010 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-20841354

RESUMO

In this study, we tested the efficacy of increasing liver glycogen synthase to improve blood glucose homeostasis. The overexpression of wild-type liver glycogen synthase in rats had no effect on blood glucose homeostasis in either the fed or the fasted state. In contrast, the expression of a constitutively active mutant form of the enzyme caused a significant lowering of blood glucose in the former but not the latter state. Moreover, it markedly enhanced the clearance of blood glucose when fasted rats were challenged with a glucose load. Hepatic glycogen stores in rats overexpressing the activated mutant form of liver glycogen synthase were enhanced in the fed state and in response to an oral glucose load but showed a net decline during fasting. In order to test whether these effects were maintained during long term activation of liver glycogen synthase, we generated liver-specific transgenic mice expressing the constitutively active LGS form. These mice also showed an enhanced capacity to store glycogen in the fed state and an improved glucose tolerance when challenged with a glucose load. Thus, we conclude that the activation of liver glycogen synthase improves glucose tolerance in the fed state without compromising glycogenolysis in the postabsorptive state. On the basis of these findings, we propose that the activation of liver glycogen synthase may provide a potential strategy for improvement of glucose tolerance in the postprandial state.


Assuntos
Glicemia , Expressão Gênica , Glicogênio Sintase/genética , Glicogênio Sintase/metabolismo , Glicogênio Hepático/metabolismo , Fígado/metabolismo , Animais , Fígado/enzimologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Ratos , Ratos Transgênicos , Ratos Wistar
9.
Nat Neurosci ; 10(11): 1407-13, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17952067

RESUMO

Glycogen synthesis is normally absent in neurons. However, inclusion bodies resembling abnormal glycogen accumulate in several neurological diseases, particularly in progressive myoclonus epilepsy or Lafora disease. We show here that mouse neurons have the enzymatic machinery for synthesizing glycogen, but that it is suppressed by retention of muscle glycogen synthase (MGS) in the phosphorylated, inactive state. This suppression was further ensured by a complex of laforin and malin, which are the two proteins whose mutations cause Lafora disease. The laforin-malin complex caused proteasome-dependent degradation both of the adaptor protein targeting to glycogen, PTG, which brings protein phosphatase 1 to MGS for activation, and of MGS itself. Enforced expression of PTG led to glycogen deposition in neurons and caused apoptosis. Therefore, the malin-laforin complex ensures a blockade of neuronal glycogen synthesis even under intense glycogenic conditions. Here we explain the formation of polyglucosan inclusions in Lafora disease by demonstrating a crucial role for laforin and malin in glycogen synthesis.


Assuntos
Apoptose/fisiologia , Regulação da Expressão Gênica/fisiologia , Glicogênio/metabolismo , Neurônios/metabolismo , Animais , Astrócitos/fisiologia , Proteínas de Transporte/farmacologia , Células Cultivadas , Córtex Cerebral/citologia , Embrião de Mamíferos , Regulação da Expressão Gênica/efeitos dos fármacos , Proteína Glial Fibrilar Ácida/metabolismo , Glicogênio Fosforilase/metabolismo , Glicogênio Sintase/metabolismo , Humanos , Marcação In Situ das Extremidades Cortadas/métodos , Camundongos , Mutação/fisiologia , Proteínas Tirosina Fosfatases não Receptoras/farmacologia , Interferência de RNA/fisiologia , Transfecção , Tubulina (Proteína)/metabolismo , Ubiquitina-Proteína Ligases
10.
STAR Protoc ; 2(3): 100608, 2021 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-34189473

RESUMO

13C nuclear spin hyperpolarization can increase the sensitivity of detection in an MRI experiment by more than 10,000-fold. 13C magnetic resonance spectroscopic imaging (MRSI) of hyperpolarized 13C label exchange between injected [1-13C]pyruvate and the endogenous tumor lactate pool can be used clinically to assess tumor grade and response to treatment. We describe here an experimental protocol for using this technique in patient-derived and established cell line xenograft models of breast cancer in the mouse. For complete details on the use and execution of this protocol, please refer to Ros et al. (2020).


Assuntos
Neoplasias da Mama/metabolismo , Ácido Pirúvico/metabolismo , Animais , Neoplasias da Mama/patologia , Isótopos de Carbono , Modelos Animais de Doenças , Feminino , Xenoenxertos , Humanos , Imageamento por Ressonância Magnética/métodos , Camundongos
11.
Hum Mol Genet ; 17(5): 667-78, 2008 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-18029386

RESUMO

Lafora progressive myoclonus epilepsy (LD) is a fatal autosomal recessive neurodegenerative disorder characterized by the presence of glycogen-like intracellular inclusions called Lafora bodies. LD is caused by mutations in two genes, EPM2A and EPM2B, encoding respectively laforin, a dual-specificity protein phosphatase, and malin, an E3 ubiquitin ligase. Previously, we and others have suggested that the interactions between laforin and PTG (a regulatory subunit of type 1 protein phosphatase) and between laforin and malin are critical in the pathogenesis of LD. Here, we show that the laforin-malin complex downregulates PTG-induced glycogen synthesis in FTO2B hepatoma cells through a mechanism involving ubiquitination and degradation of PTG. Furthermore, we demonstrate that the interaction between laforin and malin is a regulated process that is modulated by the AMP-activated protein kinase (AMPK). These findings provide further insights into the critical role of the laforin-malin complex in the control of glycogen metabolism and unravel a novel link between the energy sensor AMPK and glycogen metabolism. These data advance our understanding of the functional role of laforin and malin, which hopefully will facilitate the development of appropriate LD therapies.


Assuntos
Proteínas de Transporte/genética , Glicogênio/biossíntese , Complexos Multienzimáticos/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Tirosina Fosfatases não Receptoras/genética , Proteínas Quinases Ativadas por AMP , Adenoviridae/genética , Sequência de Aminoácidos , Animais , Sítios de Ligação , Proteínas de Transporte/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Fenômenos Fisiológicos Celulares , Escherichia coli/genética , Glicogênio/análise , Proteínas de Fluorescência Verde/metabolismo , Humanos , Rim/citologia , Modelos Biológicos , Dados de Sequência Molecular , Mutação , Fosforilação , Ligação Proteica , Estrutura Terciária de Proteína , Proteínas Tirosina Fosfatases não Receptoras/química , Proteínas Tirosina Fosfatases não Receptoras/metabolismo , Ratos , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/metabolismo , Estatística como Assunto , Transfecção , Técnicas do Sistema de Duplo-Híbrido , Ubiquitina-Proteína Ligases , Ubiquitinação
12.
EJNMMI Res ; 10(1): 151, 2020 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-33296043

RESUMO

INTRODUCTION: Trialing novel cancer therapies in the clinic would benefit from imaging agents that can detect early evidence of treatment response. The timing, extent and distribution of cell death in tumors following treatment can give an indication of outcome. We describe here an 18F-labeled derivative of a phosphatidylserine-binding protein, the C2A domain of Synaptotagmin-I (C2Am), for imaging tumor cell death in vivo using PET. METHODS: A one-pot, two-step automated synthesis of N-(5-[18F]fluoropentyl)maleimide (60 min synthesis time, > 98% radiochemical purity) has been developed, which was used to label the single cysteine residue in C2Am within 30 min at room temperature. Binding of 18F-C2Am to apoptotic and necrotic tumor cells was assessed in vitro, and also in vivo, by dynamic PET and biodistribution measurements in mice bearing human tumor xenografts treated with a TRAILR2 agonist or with conventional chemotherapy. C2Am detection of tumor cell death was validated by correlation of probe binding with histological markers of cell death in tumor sections obtained immediately after imaging. RESULTS: 18F-C2Am showed a favorable biodistribution profile, with predominantly renal clearance and minimal retention in spleen, liver, small intestine, bone and kidney, at 2 h following probe administration. 18F-C2Am generated tumor-to-muscle (T/m) ratios of 6.1 ± 2.1 and 10.7 ± 2.4 within 2 h of probe administration in colorectal and breast tumor models, respectively, following treatment with the TRAILR2 agonist. The levels of cell death (CC3 positivity) following treatment were 12.9-58.8% and 11.3-79.7% in the breast and colorectal xenografts, respectively. Overall, a 20% increase in CC3 positivity generated a one unit increase in the post/pre-treatment tumor contrast. Significant correlations were found between tracer uptake post-treatment, at 2 h post-probe administration, and histological markers of cell death (CC3: Pearson R = 0.733, P = 0.0005; TUNEL: Pearson R = 0.532, P = 0.023). CONCLUSION: The rapid clearance of 18F-C2Am from the blood pool and low kidney retention allowed the spatial distribution of cell death in a tumor to be imaged during the course of therapy, providing a rapid assessment of tumor treatment response. 18F-C2Am has the potential to be used in the clinic to assess early treatment response in tumors.

13.
Sci Signal ; 13(652)2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-33023985

RESUMO

Tumor-associated macrophages (TAMs) can exist in pro- and anti-inflammatory states. Anti-inflammatory TAMs (also referred to as M2-polarized) generally suppress antitumor immune responses and enhance the metastatic progression of cancer. To explore the mechanisms behind this phenomenon, we isolated macrophages from mice and humans, polarized them ex vivo, and examined their functional interaction with breast cancer cells in culture and in mice. We found that anti-inflammatory TAMs promoted a metabolic state in breast cancer cells that supported various protumorigenic phenotypes. Anti-inflammatory TAMs secreted the cytokine TGF-ß that, upon engagement of its receptors in breast cancer cells, suppressed the abundance of the transcription factor STAT1 and, consequently, decreased that of the metabolic enzyme succinate dehydrogenase (SDH) in the tumor cells. The decrease in SDH levels in tumor cells resulted in an accumulation of succinate, which enhanced the stability of the transcription factor HIF1α and reprogrammed cell metabolism to a glycolytic state. TAM depletion-repletion experiments in a 4T1 mouse model additionally revealed that anti-inflammatory macrophages promoted HIF-associated vascularization and expression of the immunosuppressive protein PD-L1 in tumors. The findings suggest that anti-inflammatory TAMs promote tumor-associated angiogenesis and immunosuppression by altering metabolism in breast cancer cells.


Assuntos
Neoplasias da Mama/metabolismo , Carcinogênese/metabolismo , Macrófagos/metabolismo , Neoplasias Mamárias Experimentais/metabolismo , Succinato Desidrogenase/metabolismo , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Carcinogênese/genética , Linhagem Celular Tumoral , Células Cultivadas , Técnicas de Cocultura , Feminino , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Mamárias Experimentais/genética , Neoplasias Mamárias Experimentais/patologia , Camundongos , Camundongos Endogâmicos BALB C , Microscopia de Fluorescência , Interferência de RNA , Transdução de Sinais , Succinato Desidrogenase/genética , Fator de Crescimento Transformador beta/metabolismo
14.
Cancer Cell ; 38(4): 516-533.e9, 2020 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-32976773

RESUMO

PIK3CA, encoding the PI3Kα isoform, is the most frequently mutated oncogene in estrogen receptor (ER)-positive breast cancer. Isoform-selective PI3K inhibitors are used clinically but intrinsic and acquired resistance limits their utility. Improved selection of patients that will benefit from these drugs requires predictive biomarkers. We show here that persistent FOXM1 expression following drug treatment is a biomarker of resistance to PI3Kα inhibition in ER+ breast cancer. FOXM1 drives expression of lactate dehydrogenase (LDH) but not hexokinase 2 (HK-II). The downstream metabolic changes can therefore be detected using MRI of LDH-catalyzed hyperpolarized 13C label exchange between pyruvate and lactate but not by positron emission tomography measurements of HK-II-mediated trapping of the glucose analog 2-deoxy-2-[18F]fluorodeoxyglucose. Rapid assessment of treatment response in breast cancer using this imaging method could help identify patients that benefit from PI3Kα inhibition and design drug combinations to counteract the emergence of resistance.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Classe I de Fosfatidilinositol 3-Quinases/antagonistas & inibidores , Proteína Forkhead Box M1/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Classe I de Fosfatidilinositol 3-Quinases/genética , Classe I de Fosfatidilinositol 3-Quinases/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Proteína Forkhead Box M1/genética , Fulvestranto/administração & dosagem , Humanos , Imidazóis/administração & dosagem , Células MCF-7 , Imageamento por Ressonância Magnética/métodos , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos SCID , Oxazepinas/administração & dosagem , Receptores de Estrogênio/metabolismo , Tamoxifeno/administração & dosagem , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
15.
Cancer Res ; 79(14): 3557-3569, 2019 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-31088837

RESUMO

Metabolic imaging has been widely used to measure the early responses of tumors to treatment. Here, we assess the abilities of PET measurement of [18F]FDG uptake and MRI measurement of hyperpolarized [1-13C]pyruvate metabolism to detect early changes in glycolysis following treatment-induced cell death in human colorectal (Colo205) and breast adenocarcinoma (MDA-MB-231) xenografts in mice. A TRAIL agonist that binds to human but not mouse cells induced tumor-selective cell death. Tumor glycolysis was assessed by injecting [1,6-13C2]glucose and measuring 13C-labeled metabolites in tumor extracts. Injection of hyperpolarized [1-13C]pyruvate induced rapid reduction in lactate labeling. This decrease, which correlated with an increase in histologic markers of cell death and preceded decrease in tumor volume, reflected reduced flux from glucose to lactate and decreased lactate concentration. However, [18F]FDG uptake and phosphorylation were maintained following treatment, which has been attributed previously to increased [18F]FDG uptake by infiltrating immune cells. Quantification of [18F]FDG uptake in flow-sorted tumor and immune cells from disaggregated tumors identified CD11b+/CD45+ macrophages as the most [18F]FDG-avid cell type present, yet they represented <5% of the cells present in the tumors and could not explain the failure of [18F]FDG-PET to detect treatment response. MRI measurement of hyperpolarized [1-13C]pyruvate metabolism is therefore a more sensitive marker of the early decreases in glycolytic flux that occur following cell death than PET measurements of [18F]FDG uptake. SIGNIFICANCE: These findings demonstrate superior sensitivity of MRI measurement of hyperpolarized [1-13C]pyruvate metabolism versus PET measurement of 18F-FDG uptake for detecting early changes in glycolysis following treatment-induced tumor cell death.


Assuntos
Neoplasias Colorretais/diagnóstico por imagem , Neoplasias de Mama Triplo Negativas/diagnóstico por imagem , Adenocarcinoma/diagnóstico , Adenocarcinoma/metabolismo , Animais , Antineoplásicos/farmacologia , Isótopos de Carbono , Morte Celular/fisiologia , Linhagem Celular Tumoral , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Feminino , Fluordesoxiglucose F18/farmacocinética , Glicólise/efeitos dos fármacos , Xenoenxertos , Humanos , Ácido Láctico/metabolismo , Imageamento por Ressonância Magnética/métodos , Camundongos Endogâmicos BALB C , Camundongos Nus , Tomografia por Emissão de Pósitrons/métodos , Ácido Pirúvico/metabolismo , Compostos Radiofarmacêuticos/farmacocinética , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/agonistas , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia
16.
Endocr Pathol ; 19(3): 190-6, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18446450

RESUMO

Small cell carcinomas may occur in the thyroid gland. Infrequently, they are primary tumors, and have been interpreted as variants of medullary thyroid carcinoma. However, the vast majority of small cell carcinomas involving the thyroid gland are metastatic tumors. In some cases, demonstration of the primary tumor is not easy. An example of a small cell carcinoma metastatic to the thyroid is presented in this report. The primary tumor was a small cell carcinoma that occurred as a minor component in a transitional carcinoma of the urinary bladder. The microscopical and immunohistochemical features of both tumors, in the thyroid and the bladder, were identical. Moreover, both tumors exhibited an identical mutation in p53, as well as similar loss of heterozygosity at 10q23 and RASSF1A promoter hypermethylation, clearly indicating that the bladder tumor was the site for the primary tumor of the patient.


Assuntos
Carcinoma de Células Pequenas/genética , Carcinoma de Células Pequenas/secundário , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/secundário , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/patologia , Adenocarcinoma/patologia , Sequência de Bases , Carcinoma de Células Pequenas/metabolismo , Carcinoma de Células de Transição/patologia , Metilação de DNA , Análise Mutacional de DNA , Humanos , Imuno-Histoquímica , Perda de Heterozigosidade , Masculino , Pessoa de Meia-Idade , Neoplasias Primárias Múltiplas/patologia , Regiões Promotoras Genéticas/genética , Neoplasias da Próstata/patologia , Neoplasias da Glândula Tireoide/metabolismo , Proteína Supressora de Tumor p53/genética , Proteínas Supressoras de Tumor/genética
17.
Cancer Res ; 78(18): 5408-5418, 2018 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-30054337

RESUMO

13C MRI of hyperpolarized [1-13C]pyruvate metabolism has been used in oncology to detect disease, investigate disease progression, and monitor response to treatment with a view to guiding treatment in individual patients. This technique has translated to the clinic with initial studies in prostate cancer. Here, we use the technique to investigate its potential uses in patients with glioblastoma (GB). We assessed the metabolism of hyperpolarized [1-13C]pyruvate in an orthotopically implanted cell line model (U87) of GB and in patient-derived tumors, where these were produced by orthotopic implantation of cells derived from different patients. Lactate labeling was higher in the U87 tumor when compared with patient-derived tumors, which displayed intertumoral heterogeneity, reflecting the intra- and intertumoral heterogeneity in the patients' tumors from which they were derived. Labeling in some patient-derived tumors could be observed before their appearance in morphologic images, whereas in other tumors it was not significantly greater than the surrounding brain. Increased lactate labeling in tumors correlated with c-Myc-driven expression of hexokinase 2, lactate dehydrogenase A, and the monocarboxylate transporters and was accompanied by increased radioresistance. Because c-Myc expression correlates with glioma grade, this study demonstrates that imaging with hyperpolarized [1-13C]pyruvate could be used clinically with patients with GB to determine disease prognosis, to detect early responses to drugs that modulate c-Myc expression, and to select tumors, and regions of tumors for increased radiotherapy dose.Significance: Metabolic imaging with hyperpolarized [1-13C]pyruvate detects low levels of c-Myc-driven glycolysis in patient-derived glioblastoma models, which, when translated to the clinic, could be used to detect occult disease, determine disease prognosis, and target radiotherapy. Cancer Res; 78(18); 5408-18. ©2018 AACR.


Assuntos
Neoplasias Encefálicas/metabolismo , Glioblastoma/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Animais , Neoplasias Encefálicas/diagnóstico por imagem , Linhagem Celular Tumoral , Modelos Animais de Doenças , Doxiciclina/farmacologia , Exoma , Feminino , Glioblastoma/diagnóstico por imagem , Glicólise , Xenoenxertos , Humanos , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Masculino , Transplante de Neoplasias , Prognóstico , RNA Interferente Pequeno/metabolismo , Ratos , Ratos Nus
20.
Sci Transl Med ; 10(466)2018 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-30404863

RESUMO

Existing methods to improve detection of circulating tumor DNA (ctDNA) have focused on genomic alterations but have rarely considered the biological properties of plasma cell-free DNA (cfDNA). We hypothesized that differences in fragment lengths of circulating DNA could be exploited to enhance sensitivity for detecting the presence of ctDNA and for noninvasive genomic analysis of cancer. We surveyed ctDNA fragment sizes in 344 plasma samples from 200 patients with cancer using low-pass whole-genome sequencing (0.4×). To establish the size distribution of mutant ctDNA, tumor-guided personalized deep sequencing was performed in 19 patients. We detected enrichment of ctDNA in fragment sizes between 90 and 150 bp and developed methods for in vitro and in silico size selection of these fragments. Selecting fragments between 90 and 150 bp improved detection of tumor DNA, with more than twofold median enrichment in >95% of cases and more than fourfold enrichment in >10% of cases. Analysis of size-selected cfDNA identified clinically actionable mutations and copy number alterations that were otherwise not detected. Identification of plasma samples from patients with advanced cancer was improved by predictive models integrating fragment length and copy number analysis of cfDNA, with area under the curve (AUC) >0.99 compared to AUC <0.80 without fragmentation features. Increased identification of cfDNA from patients with glioma, renal, and pancreatic cancer was achieved with AUC > 0.91 compared to AUC < 0.5 without fragmentation features. Fragment size analysis and selective sequencing of specific fragment sizes can boost ctDNA detection and could complement or provide an alternative to deeper sequencing of cfDNA.


Assuntos
DNA Tumoral Circulante/análise , DNA Tumoral Circulante/química , Animais , DNA Tumoral Circulante/sangue , Variações do Número de Cópias de DNA/genética , Genoma Humano , Humanos , Aprendizado de Máquina , Camundongos , Mutação/genética , Sequenciamento Completo do Genoma
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