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1.
J Biol Chem ; 300(2): 105650, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38237681

RESUMO

Individual oncogenic KRAS mutants confer distinct differences in biochemical properties and signaling for reasons that are not well understood. KRAS activity is closely coupled to protein dynamics and is regulated through two interconverting conformations: state 1 (inactive, effector binding deficient) and state 2 (active, effector binding enabled). Here, we use 31P NMR to delineate the differences in state 1 and state 2 populations present in WT and common KRAS oncogenic mutants (G12C, G12D, G12V, G13D, and Q61L) bound to its natural substrate GTP or a commonly used nonhydrolyzable analog GppNHp (guanosine-5'-[(ß,γ)-imido] triphosphate). Our results show that GppNHp-bound proteins exhibit significant state 1 population, whereas GTP-bound KRAS is primarily (90% or more) in state 2 conformation. This observation suggests that the predominance of state 1 shown here and in other studies is related to GppNHp and is most likely nonexistent in cells. We characterize the impact of this differential conformational equilibrium of oncogenic KRAS on RAF1 kinase effector RAS-binding domain and intrinsic hydrolysis. Through a KRAS G12C drug discovery, we have identified a novel small-molecule inhibitor, BBO-8956, which is effective against both GDP- and GTP-bound KRAS G12C. We show that binding of this inhibitor significantly perturbs state 1-state 2 equilibrium and induces an inactive state 1 conformation in GTP-bound KRAS G12C. In the presence of BBO-8956, RAF1-RAS-binding domain is unable to induce a signaling competent state 2 conformation within the ternary complex, demonstrating the mechanism of action for this novel and active-conformation inhibitor.


Assuntos
Proteínas Proto-Oncogênicas p21(ras) , Proteínas ras , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Proteínas ras/metabolismo , Guanosina Trifosfato/metabolismo , Espectroscopia de Ressonância Magnética , Transdução de Sinais , Mutação
2.
Sensors (Basel) ; 19(23)2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31810237

RESUMO

Dielectrophoresis is an electric force experienced by particles subjected to non-uniform electric fields. Recently, several technologies have been developed focused on the use of dielectrophoretic force (DEP) to manipulate and detect cells. On the other hand, there is no such great development in the field of DEP-based cell discrimination methods. Despite the demand for methods to differentiate biological cell states, most DEP developed methods have been focused on differentiation through geometric parameters. The novelty of the present work relies upon the point that a DEP force cell measurement is used as a discrimination method, capable of detecting heat killed yeast cells from the alive ones. Thermal treatment is used as an example of different biological state of cells. It comes from the fact that biological properties have their reflection in the electric properties of the particle, in this case a yeast cell. To demonstrate such capability of the method, 279 heat-killed cells were measured and compared with alive cells data from the literature. For each cell, six speeds were taken at different points in its trajectory inside a variable non-uniform electric field. The electric parameters in cell wall conductivity, cell membrane conductivity, cell membrane permittivity of the yeast cell from bibliography explains the DEP experimental force measured. Finally, alive and heat-treated cells were distinguished based on that measure. Our results can be explained through the well-known damage of cell structure characteristics of heat-killed cells.


Assuntos
Eletroforese/métodos , Membrana Celular/metabolismo , Eletroquímica , Leveduras/metabolismo
3.
Sensors (Basel) ; 19(17)2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31484453

RESUMO

Dielectrophoretic force is an electric force experienced by particles subjected to non-uniform electric fields. In recent years, plenty of dielectrophoretic force (DEP) applications have been developed. Most of these works have been centered on particle positioning and manipulation. DEP particle characterization has been left in the background. Likewise, these characterizations have studied the electric properties of particles from a qualitative point of view. This article focuses on the quantitative measurement of cells' dielectric force, specifically yeast cells. The measures are obtained as the results of a theoretical model and an instrumental method, both of which are developed and described in the present article, based on a dielectrophoretic chamber made of two V-shaped placed electrodes. In this study, 845 cells were measured. For each one, six speeds were taken at different points in its trajectory. Furthermore, the chamber design is repeatable, and this was the first time that measurements of dielectrophoretic force and cell velocity for double yeast cells were accomplished. To validate the results obtained in the present research, the results have been compared with the dielectric properties of yeast cells collected in the pre-existing literature.


Assuntos
Eletroforese/métodos , Modelos Teóricos
4.
Sensors (Basel) ; 18(2)2018 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-29370142

RESUMO

The characterization of the microclimatic conditions is fundamental for the preventive conservation of archaeological sites. In this context, the identification of the factors that influence the thermo-hygrometric equilibrium is key to determine the causes of cultural heritage deterioration. In this work, a characterization of the thermo-hygrometric conditions of Casa di Diana (Ostia Antica, Italy) is carried out analyzing the data of temperature and relative humidity recorded by a system of sensors with high monitoring frequency. Sensors are installed in parallel, calibrated and synchronized with a microcontroller. A data set of 793,620 data, arranged in a matrix with 66,135 rows and 12 columns, was used. Furthermore, the influence of human impact (visitors) is evaluated through a multiple linear regression model and a logistic regression model. The visitors do not affect the environmental humidity as it is very high and constant all the year. The results show a significant influence of the visitors in the upset of the thermal balance. When a tourist guide takes place, the probability that the hourly temperature variation reaches values higher than its monthly average is 10.64 times higher than it remains equal or less to its monthly average. The analysis of the regression residuals shows the influence of outdoor climatic variables in the thermal balance, such as solar radiation or ventilation.

5.
Int J Cancer ; 139(6): 1340-9, 2016 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-27170265

RESUMO

Gas6 and its receptors Axl, Mer and Tyro-3 (TAM) are highly expressed in human malignancy suggesting that signaling through this axis may be tumor-promoting. In pancreatic ductal adenocarcinoma (PDAC), Gas6 and the TAM receptor Axl are frequently co-expressed and their co-expression correlates with poor survival. A strategy was devised to generate fully human neutralizing antibodies against Gas6 using XenoMouse® technology. Hybridoma supernatants were selected based on their ability to inhibit Gas6 binding to the receptor Axl and block Gas6-induced Axl phosphorylation in human cells. Two purified antibodies isolated from the screened hybridomas, GMAB1 and GMAB2, displayed optimal cellular potency which was comparable to that of the soluble extracellular domain of the receptor Axl (Axl-Fc). In vivo characterization of GMAB1 was conducted using a pharmacodynamic assay that measured inhibition of Gas6-induced Akt activation in the mouse spleen. Treatment of mice with a single dose (100-1000 µg) of GMAB1 led to greater than 90% inhibition of Gas6-induced phosphorylated Akt (pAkt) for up to 72 hr. Based on the target coverage observed in the PD assay, the efficacy of GMAB1 was tested against human pancreatic adenocarcinoma xenografts. At doses of 50 µg and 150 µg, twice weekly, GMAB1 was able to inhibit 55% and 76% of tumor growth, respectively (p < 0.001 for both treatments vs. control Ig). When combined with gemcitabine, GMAB1 significantly inhibited tumor growth compared to either agent alone (p < 0.001). Together, the data suggest that Gas6 neutralization may be important as a potential strategy for the treatment of PDAC.


Assuntos
Anticorpos Neutralizantes/farmacologia , Anticorpos/farmacologia , Comunicação Autócrina/efeitos dos fármacos , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/patologia , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Animais , Anticorpos/imunologia , Anticorpos Neutralizantes/imunologia , Antineoplásicos/farmacologia , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/imunologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Feminino , Humanos , Camundongos , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/imunologia , Fosforilação/efeitos dos fármacos , Ligação Proteica/efeitos dos fármacos , Transporte Proteico/efeitos dos fármacos , Proteínas Proto-Oncogênicas/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto , Receptor Tirosina Quinase Axl , Neoplasias Pancreáticas
6.
Sensors (Basel) ; 16(8)2016 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-27537886

RESUMO

Monitoring temperature and relative humidity of the environment to which artefacts are exposed is fundamental in preventive conservation studies. The common approach in setting measuring instruments is the choice of a high sampling rate to detect short fluctuations and increase the accuracy of statistical analysis. However, in recent cultural heritage standards the evaluation of variability is based on moving average and short fluctuations and therefore massive acquisition of data in slowly-changing indoor environments could end up being redundant. In this research, the sampling frequency to set a datalogger in a museum room and inside a microclimate frame is investigated by comparing the outcomes obtained from datasheets associated with different sampling conditions. Thermo-hygrometric data collected in the Sorolla room of the Pio V Museum of Valencia (Spain) were used and the widely consulted recommendations issued in UNI 10829:1999 and EN 15757:2010 standards and in the American Society of Heating, Air-Conditioning and Refrigerating Engineers (ASHRAE) guidelines were applied. Hourly sampling proved effective in obtaining highly reliable results. Furthermore, it was found that in some instances daily means of data sampled every hour can lead to the same conclusions as those of high frequency. This allows us to improve data logging design and manageability of the resulting datasheets.

7.
Nat Med ; 30(2): 443-454, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38321220

RESUMO

Compromised vascular endothelial barrier function is a salient feature of diabetic complications such as sight-threatening diabetic macular edema (DME). Current standards of care for DME manage aspects of the disease, but require frequent intravitreal administration and are poorly effective in large subsets of patients. Here we provide evidence that an elevated burden of senescent cells in the retina triggers cardinal features of DME pathology and conduct an initial test of senolytic therapy in patients with DME. In cell culture models, sustained hyperglycemia provoked cellular senescence in subsets of vascular endothelial cells displaying perturbed transendothelial junctions associated with poor barrier function and leading to micro-inflammation. Pharmacological elimination of senescent cells in a mouse model of DME reduces diabetes-induced retinal vascular leakage and preserves retinal function. We then conducted a phase 1 single ascending dose safety study of UBX1325 (foselutoclax), a senolytic small-molecule inhibitor of BCL-xL, in patients with advanced DME for whom anti-vascular endothelial growth factor therapy was no longer considered beneficial. The primary objective of assessment of safety and tolerability of UBX1325 was achieved. Collectively, our data suggest that therapeutic targeting of senescent cells in the diabetic retina with a BCL-xL inhibitor may provide a long-lasting, disease-modifying intervention for DME. This hypothesis will need to be verified in larger clinical trials. ClinicalTrials.gov identifier: NCT04537884 .


Assuntos
Diabetes Mellitus , Retinopatia Diabética , Edema Macular , Animais , Camundongos , Humanos , Edema Macular/tratamento farmacológico , Edema Macular/etiologia , Retinopatia Diabética/tratamento farmacológico , Inibidores da Angiogênese/uso terapêutico , Células Endoteliais , Senoterapia , Senescência Celular
8.
Nat Cancer ; 5(1): 66-84, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38151625

RESUMO

Chromosomal instability (CIN) is a hallmark of cancer, caused by persistent errors in chromosome segregation during mitosis. Aggressive cancers like high-grade serous ovarian cancer (HGSOC) and triple-negative breast cancer (TNBC) have a high frequency of CIN and TP53 mutations. Here, we show that inhibitors of the KIF18A motor protein activate the mitotic checkpoint and selectively kill chromosomally unstable cancer cells. Sensitivity to KIF18A inhibition is enriched in TP53-mutant HGSOC and TNBC cell lines with CIN features, including in a subset of CCNE1-amplified, CDK4-CDK6-inhibitor-resistant and BRCA1-altered cell line models. Our KIF18A inhibitors have minimal detrimental effects on human bone marrow cells in culture, distinct from other anti-mitotic agents. In mice, inhibition of KIF18A leads to robust anti-cancer effects with tumor regression observed in human HGSOC and TNBC models at well-tolerated doses. Collectively, our results provide a rational therapeutic strategy for selective targeting of CIN cancers via KIF18A inhibition.


Assuntos
Cinesinas , Neoplasias de Mama Triplo Negativas , Humanos , Animais , Camundongos , Cinesinas/genética , Cinesinas/metabolismo , Mitose/genética , Linhagem Celular , Pontos de Checagem da Fase M do Ciclo Celular
9.
Sensors (Basel) ; 13(3): 2700-18, 2013 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-23447005

RESUMO

Cultural Heritage preventive conservation requires the monitoring of the parameters involved in the process of deterioration of artworks. Thus, both long-term monitoring of the environmental parameters as well as further analysis of the recorded data are necessary. The long-term monitoring at frequencies higher than 1 data point/day generates large volumes of data that are difficult to store, manage and analyze. This paper presents software which uses a free open source database engine that allows managing and interacting with huge amounts of data from environmental monitoring of cultural heritage sites. It is of simple operation and offers multiple capabilities, such as detection of anomalous data, inquiries, graph plotting and mean trajectories. It is also possible to export the data to a spreadsheet for analyses with more advanced statistical methods (principal component analysis, ANOVA, linear regression, etc.). This paper also deals with a practical application developed for the Renaissance frescoes of the Cathedral of Valencia. The results suggest infiltration of rainwater in the vault and weekly relative humidity changes related with the religious service schedules.


Assuntos
Arte , Armazenamento e Recuperação da Informação , Software , Cultura , Monitoramento Ambiental , Humanos , Microclima
10.
Sensors (Basel) ; 13(9): 11407-23, 2013 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-24064599

RESUMO

The mudéjar church of Santa María (Ateca) is valuable for its architecture and the altarpiece contained inside. Ateca is a village with continental climate characterized by cold winters and hot summers. In this paper we are interested in analysing the effect of temperature and relative humidity (RH) changes produced by the heating system on the altarpiece. Therefore, a monitoring system of 15 temperature and 15 relative humidity sensors was installed with a recording frequency of a data point per minute. The main contribution of this paper is the quantitative study of the effect of the heating system on the thermo-hygrometric parameters using statistical techniques such as ANOVA, mean daily trajectories or bivariate plots, and the proposal of an innovative dynamic contour plot. As results, the heating system produces a substantial increase (decrease) of temperature (RH) causing an hourly variation of these physical parameters detrimental to the conservation of the altarpiece, especially in its higher areas.


Assuntos
Arte , Monitoramento Ambiental/instrumentação , Monitoramento Ambiental/métodos , Calefação/métodos , Umidade , Termografia/instrumentação , Transdutores , Desenho de Equipamento , Análise de Falha de Equipamento , Reprodutibilidade dos Testes , Estações do Ano , Sensibilidade e Especificidade , Espanha
11.
Sensors (Basel) ; 13(8): 9729-46, 2013 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-23899937

RESUMO

Preventive conservation requires monitoring and control of the parameters involved in the deterioration process, mainly temperature and relative humidity. It is important to characterise an archaeological site prior to carrying out comparative studies in the future for preventive conservation, either by regular studies to verify whether the conditions are constant, or occasional ones when the boundary conditions are altered. There are numerous covered archaeological sites, but few preventive conservation works that give special attention to the type of cover installed. In particular, there is no background of microclimatic studies in sites that are in the ground and, as in the Plaza de l'Almoina (Valencia, Spain), are buried and partially covered by a transparent roof. A large effect of the transparent cover was found by the sensors located below this area, with substantial increases in temperature and a decrease in the relative humidity during the day. Surrounding zones also have values above the recommended temperature values. On the other hand, the influence of a buried water drainage line near the site is notable, causing an increase in relative humidity levels in the surrounding areas. Multivariate statistical analyses enabled us to characterise the microclimate of the archaeological site, allowing future testing to determine whether the conservation conditions have been altered.


Assuntos
Arqueologia/instrumentação , Conservação dos Recursos Naturais/métodos , Monitoramento Ambiental/instrumentação , Umidade , Análise Multivariada , Tecnologia de Sensoriamento Remoto/instrumentação , Termografia/instrumentação , Arqueologia/métodos , Desenho de Equipamento , Análise de Falha de Equipamento , Tecnologia de Sensoriamento Remoto/métodos , Espanha , Transdutores , Água/análise
12.
Sensors (Basel) ; 13(6): 8000-12, 2013 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-23793020

RESUMO

In this study we propose an electronic system for linear positioning of a magnet independent of its modulus, which could vary because of aging, different fabrication process, etc. The system comprises a linear array of 24 Hall Effect sensors of proportional response. The data from all sensors are subject to a pretreatment (normalization) by row (position) making them independent on the temporary variation of its magnetic field strength. We analyze the particular case of the individual flow in milking of goats. The multiple regression analysis allowed us to calibrate the electronic system with a percentage of explanation R² = 99.96%. In our case, the uncertainty in the linear position of the magnet is 0.51 mm that represents 0.019 L of goat milk. The test in farm compared the results obtained by direct reading of the volume with those obtained by the proposed electronic calibrated system, achieving a percentage of explanation of 99.05%.

13.
Int J Mol Sci ; 14(7): 13782-95, 2013 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-23823800

RESUMO

Calorie restriction (CR) inhibits prostate cancer progression, partially through modulation of the IGF axis. IGF-1 receptor (IGF-1R) blockade reduces prostate cancer xenograft growth. We hypothesized that combining calorie restriction with IGF-1R blockade would have an additive effect on prostate cancer growth. Severe combined immunodeficient mice were subcutaneously injected with 22Rv1 cells and randomized to: (1) Ad libitum feeding/intraperitoneal saline (Ad-lib); (2) Ad-lib/20 mg/kg twice weekly, intraperitoneal ganitumab [anti-IGF-1R antibody (Ad-lib/Ab)]; (3) 40% calorie restriction/intraperitoneal saline (CR); (4) CR/ intraperitoneal ganitumab, (CR/Ab). CR and ganitumab treatment were initiated one week after tumor injection. Euthanasia occurred 19 days post treatment. Results showed that CR alone decreased final tumor weight, plasma insulin and IGF-1 levels, and increased apoptosis. Ganitumab therapy alone reduced tumor growth but had no effect on final tumor weight. The combination therapy (CR/Ab) further decreased final tumor weight and proliferation, increased apoptosis in comparison to the Ad-lib group, and lowered plasma insulin levels relative to the Ad-lib and Ad-lib/Ab groups. Tumor AKT activation directly correlated with plasma IGF-1 levels. In conclusion, whereas ganitumab therapy modestly affected 22Rv1 tumor growth, combining IGF-1R blockade with calorie restriction resulted in a significant decrease in final tumor weight and improved metabolic profile.


Assuntos
Anticorpos Monoclonais/farmacologia , Anticorpos Antineoplásicos/farmacologia , Restrição Calórica , Proteínas de Neoplasias/antagonistas & inibidores , Neoplasias da Próstata/terapia , Receptores de Somatomedina/antagonistas & inibidores , Animais , Anticorpos Monoclonais Humanizados , Linhagem Celular Tumoral , Xenoenxertos , Humanos , Masculino , Camundongos , Camundongos SCID , Proteínas de Neoplasias/metabolismo , Transplante de Neoplasias , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Receptor IGF Tipo 1 , Receptores de Somatomedina/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
14.
J Immunother Cancer ; 11(5)2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37164449

RESUMO

BACKGROUND: Checkpoint inhibitors targeting cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) and programmed cell death protein 1 (PD-1)/programmed cell death ligand 1 (PD-L1) have demonstrated clinical efficacy in advanced melanoma, but only a subset of patients with inflamed tumors are responsive. Talimogene laherparepvec (T-VEC), a modified herpes simplex virus type 1 (HSV-1) expressing granulocyte-macrophage colony-stimulating factor (GM-CSF), is a first-in-class oncolytic immunotherapy approved for the treatment of melanoma and has been shown to inflame the tumor microenvironment. To evaluate the potential and mechanisms of T-VEC to elicit systemic antitumor immunity and overcome resistance to checkpoint inhibitors in murine tumor models, OncoVEXmGM-CSF was developed similarly to T-VEC, except the human GM-CSF transgene was replaced with murine GM-CSF. Previous work had demonstrated that OncoVEXmGM-CSF generated systemic antitumor immunity dependent on CD8+ T cells in an immune checkpoint-sensitive tumor cell model. METHODS: A novel B16F10 syngeneic tumor model with both HSV-1-permissive subcutaneous tumors and HSV-1-refractory experimental lung metastasis was used to study the local and systemic effects of OncoVEXmGM-CSF treatment alone or in combination with checkpoint inhibitors. RESULTS: Intratumoral injection of OncoVEXmGM-CSF in combination with an anti-CTLA-4 or anti-PD-1 blocking antibody led to increased tumor growth inhibition, a reduction in the number of lung metastases, and prolonged animal survival. OncoVEXmGM-CSF induced both neoantigen-specific and tumor antigen-specific T-cell responses. Furthermore, cured mice from the combination treatment of OncoVEXmGM-CSF and anti-CTLA-4 antibody rejected tumor rechallenges. CONCLUSIONS: These data support the concept that T-VEC and checkpoint inhibition may be an effective combination to treat patients with advanced melanoma.


Assuntos
Melanoma , Terapia Viral Oncolítica , Humanos , Animais , Camundongos , Fator Estimulador de Colônias de Granulócitos e Macrófagos , Linfócitos T CD8-Positivos/patologia , Antígenos de Neoplasias , Microambiente Tumoral
15.
Front Med (Lausanne) ; 10: 1236702, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37727759

RESUMO

Introduction: Few studies have evaluated the presence of Post COVID-19 conditions (PCC) in people from Latin America, a region that has been heavily afflicted by the COVID-19 pandemic. In this study, we describe the frequency, co-occurrence, predictors, and duration of 23 symptoms in a cohort of Mexican patients with PCC. Methods: We prospectively enrolled and followed adult patients hospitalized for severe COVID-19 at a tertiary care centre in Mexico City. The incidence of PCC symptoms was determined using questionnaires. Unsupervised clustering of PCC symptom co-occurrence and Kaplan-Meier analyses of symptom persistence were performed. The effect of baseline clinical characteristics was evaluated using Cox regression models and reported with hazard ratios (HR). Results: We found that amongst 192 patients with PCC, respiratory problems were the most prevalent and commonly co-occurred with functional activity impairment. 56% had ≥5 persistent symptoms. Symptom persistence probability at 360 days 0.78. Prior SARS-CoV-2 vaccination and infection during the Delta variant wave were associated with a shorter duration of PCC. Male sex was associated with a shorter duration of functional activity impairment and respiratory symptoms. Hypertension and diabetes were associated with a longer duration of functional impairment. Previous vaccination accelerated PCC recovery. Discussion: In our cohort, PCC symptoms were frequent (particularly respiratory and neurocognitive ones) and persistent. Importantly, prior SARS-CoV-2 vaccination resulted in a shorter duration of PCC.

16.
J Pharmacol Exp Ther ; 337(3): 644-54, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21385891

RESUMO

Ewing's and osteogenic sarcoma are two of the leading causes of cancer deaths in children and adolescents. Recent data suggest that sarcomas may depend on the insulin-like growth factor type 1 (IGF-1) receptor (IGF1R) and/or the insulin receptor (INSR) to drive tumor growth, survival, and resistance to mammalian target of rapamycin complex 1 (mTORC1) inhibitors. We evaluated the therapeutic value of ganitumab (AMG 479; C(6472)H(10028)N(1728)O(2020)S(42)), an anti-IGF1R, fully human monoclonal antibody, alone and in combination with rapamycin (mTORC1 inhibitor) in Ewing's (SK-ES-1 and A673) and osteogenic (SJSA-1) sarcoma models. IGF1R was activated by IGF-1 but not by insulin in each sarcoma model. INSR was also activated by IGF-1 in the SJSA-1 and SK-ES-1 models, but not in the A673 model where insulin was the preferred INSR ligand. Ganitumab significantly inhibited the growth of SJSA-1 and SK-ES-1 xenografts; inhibition was associated with decreased IGF1R and Akt phosphorylation, reduced total IGF1R and bromodeoxyuridine detection, and increased caspase-3 expression. Ganitumab inhibited rapamycin-induced IGF1R, Akt, and glycogen synthase kinase-3ß hyperphosphorylation in each sarcoma model. However, ganitumab in combination with rapamycin also resulted in a marked increase in INSR expression and activity in the SJSA-1 and A673 models. The in vivo efficacy of ganitumab in the two ganitumab-sensitive models (SJSA-1 and SK-ES-1) was significantly enhanced in combination with rapamycin. Our results support studying ganitumab in combination with mTORC1 inhibitors for the treatment of sarcomas and suggest that INSR signaling is an important mechanism of resistance to IGF1R blockade.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Ósseas/tratamento farmacológico , Osteossarcoma/tratamento farmacológico , Sarcoma de Ewing/tratamento farmacológico , Sirolimo/uso terapêutico , Animais , Antibióticos Antineoplásicos/farmacologia , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias Ósseas/metabolismo , Caspase 3/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Fator de Crescimento Insulin-Like I/antagonistas & inibidores , Fator de Crescimento Insulin-Like I/metabolismo , Camundongos , Camundongos Nus , Osteossarcoma/metabolismo , Fosforilação/efeitos dos fármacos , Receptor IGF Tipo 1/metabolismo , Receptor de Insulina/antagonistas & inibidores , Receptor de Insulina/metabolismo , Sarcoma de Ewing/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sirolimo/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Diabetes ; 70(10): 2237-2249, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34285117

RESUMO

Similar to insulin, central administration of IGF-1 can suppress hepatic glucose production (HGP), but it is unclear whether this effect is mediated via insulin receptors (InsRs) or IGF-1 receptors (IGF-1Rs) in the brain. To this end, we used pharmacologic and genetic approaches in combination with hyperinsulinemic-euglycemic clamps to decipher the role of these receptors in mediating central effects of IGF-1 and insulin on HGP. In rats, we observed that intracerebroventricular (ICV) administration of IGF-1 or insulin markedly increased the glucose infusion rate (GIR) by >50% and suppressed HGP (P < 0.001). However, these effects were completely prevented by preemptive ICV infusion with an IGF-1R and InsR/IGF-1R hybrid (HybridR) blocking antibody. Likewise, ICV infusion of the InsR antagonist, S961, which also can bind HybridRs, interfered with the ability of central insulin, but not IGF-1, to increase the GIR. Furthermore, hyperinsulinemic clamps in mice lacking IGF-1Rs in AgRP neurons revealed ∼30% reduction in the GIR in knockout animals, which was explained by an impaired ability of peripheral insulin to completely suppress HGP (P < 0.05). Signaling studies further revealed an impaired ability of peripheral insulin to trigger ribosomal S6 phosphorylation or phosphatidylinositol (3,4,5)-trisphosphate production in AgRP neurons lacking IGF-1Rs. In summary, these data suggest that attenuation of IGF-1R signaling in the mediobasal hypothalamus, and specifically in AgRP neurons, can phenocopy impaired regulation of HGP as previously demonstrated in mice lacking InsRs in these cells, suggesting a previously unappreciated role for IGF-1Rs and/or HybridRs in the regulation of central insulin/IGF-1 signaling in glucose metabolism.


Assuntos
Glucose/metabolismo , Insulina/farmacologia , Neurônios/fisiologia , Adulto , Proteína Relacionada com Agouti/genética , Proteína Relacionada com Agouti/metabolismo , Animais , Metabolismo dos Carboidratos/efeitos dos fármacos , Metabolismo dos Carboidratos/genética , Células Cultivadas , Técnica Clamp de Glucose , Humanos , Hipotálamo/efeitos dos fármacos , Hipotálamo/metabolismo , Injeções Intraventriculares , Insulina/administração & dosagem , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Ratos , Ratos Endogâmicos BN , Ratos Endogâmicos F344 , Receptor IGF Tipo 1/genética , Receptor IGF Tipo 1/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia
18.
Clin Cancer Res ; 27(5): 1526-1537, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33203642

RESUMO

PURPOSE: Small-cell lung cancer (SCLC) is an aggressive neuroendocrine tumor with a high relapse rate, limited therapeutic options, and poor prognosis. We investigated the antitumor activity of AMG 757, a half-life extended bispecific T-cell engager molecule targeting delta-like ligand 3 (DLL3)-a target that is selectively expressed in SCLC tumors, but with minimal normal tissue expression. EXPERIMENTAL DESIGN: AMG 757 efficacy was evaluated in SCLC cell lines and in orthotopic and patient-derived xenograft (PDX) mouse SCLC models. Following AMG 757 administration, changes in tumor volume, pharmacodynamic changes in tumor-infiltrating T cells (TILs), and the spatial relationship between the appearance of TILs and tumor histology were examined. Tolerability was assessed in nonhuman primates (NHPs). RESULTS: AMG 757 showed potent and specific killing of even those SCLC cell lines with very low DLL3 expression (<1,000 molecules per cell). AMG 757 effectively engaged systemically administered human T cells, induced T-cell activation, and redirected T cells to lyse tumor cells to promote significant tumor regression and complete responses in PDX models of SCLC and in orthotopic models of established primary lung SCLC and metastatic liver lesions. AMG 757 was well tolerated with no AMG 757-related adverse findings up to the highest tested dose (4.5 mg/kg weekly) in NHP. AMG 757 exhibits an extended half-life in NHP, which is projected to enable intermittent administration in patients. CONCLUSIONS: AMG 757 has a compelling safety and efficacy profile in preclinical studies making it a viable option for targeting DLL3-expressing SCLC tumors in the clinical setting.


Assuntos
Anticorpos Biespecíficos , Anticorpos Monoclonais , Regulação Neoplásica da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intracelular , Neoplasias Pulmonares , Proteínas de Membrana , Carcinoma de Pequenas Células do Pulmão , Linfócitos T , Animais , Feminino , Humanos , Camundongos , Anticorpos Biespecíficos/farmacologia , Anticorpos Monoclonais/farmacologia , Antineoplásicos/farmacologia , Apoptose , Proliferação de Células , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Proteínas de Membrana/antagonistas & inibidores , Camundongos Endogâmicos NOD , Camundongos SCID , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológico , Carcinoma de Pequenas Células do Pulmão/imunologia , Carcinoma de Pequenas Células do Pulmão/metabolismo , Carcinoma de Pequenas Células do Pulmão/patologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Cell Metab ; 33(4): 818-832.e7, 2021 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-33548171

RESUMO

Attenuating pathological angiogenesis in diseases characterized by neovascularization such as diabetic retinopathy has transformed standards of care. Yet little is known about the molecular signatures discriminating physiological blood vessels from their diseased counterparts, leading to off-target effects of therapy. We demonstrate that in contrast to healthy blood vessels, pathological vessels engage pathways of cellular senescence. Senescent (p16INK4A-expressing) cells accumulate in retinas of patients with diabetic retinopathy and during peak destructive neovascularization in a mouse model of retinopathy. Using either genetic approaches that clear p16INK4A-expressing cells or small molecule inhibitors of the anti-apoptotic protein BCL-xL, we show that senolysis suppresses pathological angiogenesis. Single-cell analysis revealed that subsets of endothelial cells with senescence signatures and expressing Col1a1 are no longer detected in BCL-xL-inhibitor-treated retinas, yielding a retina conducive to physiological vascular repair. These findings provide mechanistic evidence supporting the development of BCL-xL inhibitors as potential treatments for neovascular retinal disease.


Assuntos
Senescência Celular , Doenças Retinianas/patologia , Proteína bcl-X/metabolismo , Animais , Apoptose/efeitos dos fármacos , Senescência Celular/efeitos dos fármacos , Cadeia alfa 1 do Colágeno Tipo I/metabolismo , Inibidor p16 de Quinase Dependente de Ciclina/deficiência , Inibidor p16 de Quinase Dependente de Ciclina/genética , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Modelos Animais de Doenças , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Feminino , Flavonóis/química , Flavonóis/farmacologia , Flavonóis/uso terapêutico , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neovascularização Patológica , Doenças Retinianas/tratamento farmacológico , Doenças Retinianas/metabolismo , Tacrolimo/análogos & derivados , Tacrolimo/farmacologia , Proteína bcl-X/antagonistas & inibidores
20.
J Clin Med ; 10(10)2021 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-34066156

RESUMO

Differential diagnosis in epilepsy is sometimes challenging. Video-electroencephalography (V-EEG) is an essential tool in the diagnosis and management of epilepsy. The prolonged duration of V-EEG recording increases the diagnostic yield of a conventional V-EEG. The right length of monitoring for different indications is still to be established. We present a retrospective descriptive study with a sample of 50 patients with long-term V-EEG monitoring, with a mean age of 36.1 years, monitored from 2013 to 2019 at the Burgos University Hospital. The mean monitoring time was 3.6 days. Events were obtained in 76% of the patients, corresponding to epileptic seizures (ES) in 57.9% of them, with psychogenic non-epileptic seizures (PNES) in 39.5%, and with episodes of both pathologies in 2.6% of the patients. We found that the first event was highly representative, and it correlated with the rest of the events that would be recorded. Moreover, 92% of the first PNES had been captured at the end of the second day, and 89% of the first ES by the end of the third day. V-EEG for differential diagnosis between ES and PNES can be performed in hospitals without specialized epilepsy surgery units. For this indication, the duration of long-term V-EEG can be adjusted individually depending on the nature of the first event.

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