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1.
J Clin Oncol ; : JCO2302082, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38838287

RESUMO

PURPOSE: Bempegaldesleukin (BEMPEG) is a pegylated interleukin (IL)-2 cytokine prodrug engineered to provide controlled and sustained activation of the clinically validated IL-2 pathway, with the goal of preferentially activating and expanding effector CD8+ T cells and natural killer cells over immunosuppressive regulator T cells in the tumor microenvironment. The open-label, phase III randomized controlled PIVOT-09 trial investigated the efficacy and safety of BEMPEG plus nivolumab (NIVO) as first-line treatment for advanced/metastatic clear cell renal cell carcinoma (ccRCC) with intermediate-/poor-risk disease. METHODS: Patients with previously untreated advanced/metastatic ccRCC were randomly assigned (1:1) to BEMPEG plus NIVO, or investigator's choice of tyrosine kinase inhibitor (TKI; sunitinib or cabozantinib). Coprimary end points were objective response rate (ORR) by blinded independent central review and overall survival (OS) in patients with International Metastatic RCC Database Consortium (IMDC) intermediate-/poor-risk disease. RESULTS: Overall, 623 patients were randomly assigned to BEMPEG plus NIVO (n = 311) or TKI (n = 312; sunitinib n = 225, cabozantinib n = 87), of whom 514 (82.5%) had IMDC intermediate-/poor-risk disease. In patients with IMDC intermediate-/poor-risk disease, ORR with BEMPEG plus NIVO versus TKI was 23.0% (95% CI, 18.0 to 28.7) versus 30.6% (95% CI, 25.1 to 36.6; difference, -7.7 [95% CI, -15.2 to -0.2]; P = .0489), and median OS was 29.0 months versus not estimable (hazard ratio, 0.82 [95% CI, 0.61 to 1.10]; P = .192), respectively. More frequent all-grade treatment-related adverse events (TRAEs) with BEMPEG plus NIVO versus TKI included pyrexia (32.6% v 2.0%) and pruritus (31.3% v 8.8%). Grade 3/4 TRAEs were less frequent with BEMPEG plus NIVO (25.8%) versus TKI (56.5%). CONCLUSION: First-line BEMPEG plus NIVO for advanced/metastatic ccRCC did not improve efficacy in patients with intermediate-/poor-risk disease but led to fewer grade 3/4 TRAEs versus TKI.

2.
FEBS J ; 291(1): 132-141, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37789611

RESUMO

In the present study, cryo-electron tomography was used to investigate the localization of 2-oxoacid dehydrogenase complexes (OADCs) in cardiac mitochondria and mitochondrial inner membrane samples. Two classes of ordered OADC inner cores with different symmetries were distinguished and their quaternary structures modeled. One class corresponds to pyruvate dehydrogenase complexes and the other to dehydrogenase complexes of α-ketoglutarate and branched-chain α-ketoacids. OADCs were shown to be localized in close proximity to membrane-embedded respirasomes, as observed both in densely packed lamellar cristae of cardiac mitochondria and in ruptured mitochondrial samples where the dense packing is absent. This suggests the specificity of the OADC-respirasome interaction, which allows localized NADH/NAD+ exchange between OADCs and complex I of the respiratory chain. The importance of this local coupling is based on OADCs being the link between respiration, glycolysis and amino acid metabolism. The coupling of these basic metabolic processes can vary in different tissues and conditions and may be involved in the development of various pathologies. The present study shows that this important and previously missing parameter of mitochondrial complex coupling can be successfully assessed using cryo-electron tomography.


Assuntos
Cetoácidos , Complexo Piruvato Desidrogenase , 3-Metil-2-Oxobutanoato Desidrogenase (Lipoamida) , Complexo Piruvato Desidrogenase/metabolismo , Mitocôndrias Cardíacas/metabolismo , Ácidos Cetoglutáricos , Complexo Cetoglutarato Desidrogenase/metabolismo
3.
Lancet Oncol ; 24(9): 1029-1041, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37657462

RESUMO

BACKGROUND: The development of more potent selective oestrogen receptor antagonists and degraders (SERDs) that can be orally administered could help to address the limitations of current endocrine therapies. We report the primary and final analyses of the coopERA Breast Cancer study, designed to test whether giredestrant, a highly potent, non-steroidal, oral SERD, would show a stronger anti-proliferative effect than anastrozole after 2 weeks for oestrogen receptor-positive, HER2-negative, untreated early breast cancer. METHODS: In this open-label, randomised, controlled, phase 2 study, postmenopausal women were eligible if they were aged 18 years or older; had clinical T stage (cT)1c to cT4a-c (≥1·5 cm within cT1c) oestrogen receptor-positive, HER2-negative, untreated early breast cancer; an Eastern Cooperative Oncology Group performance status of 0-1; and baseline Ki67 score of at least 5%. The study was conducted at 59 hospital or clinic sites in 11 countries globally. Participants were randomly assigned (1:1) to giredestrant 30 mg oral daily or anastrozole 1 mg oral daily on days 1-14 (window-of-opportunity phase) via an interactive web-based system with permuted-block randomisation with block size of four. Randomisation was stratified by cT stage, baseline Ki67 score, and progesterone receptor status. A 16-week neoadjuvant phase comprised the same regimen plus palbociclib 125 mg oral daily on days 1-21 of a 28-day cycle, for four cycles. The primary endpoint was geometric mean relative Ki67 score change from baseline to week 2 in patients with complete central Ki67 scores at baseline and week 2 (window-of-opportunity phase). Safety was assessed in all patients who received at least one dose of study drug. The study is registered with ClinicalTrials.gov (NCT04436744) and is complete. FINDINGS: Between Sept 4, 2020, and June 22, 2021, 221 patients were enrolled and randomly assigned to the giredestrant plus palbociclib group (n=112; median age 62·0 years [IQR 57·0-68·5]) or anastrozole plus palbociclib group (n=109; median age 62·0 [57·0-67·0] years). 15 (7%) of 221 patients were Asian, three (1%) were Black or African American, 194 (88%) were White, and nine (4%) were unknown races. At data cutoff for the primary analysis (July 19, 2021), the geometric mean relative reduction of Ki67 from baseline to week 2 was -75% (95% CI -80 to -70) with giredestrant and -67% (-73 to -59) with anastrozole (p=0·043), meeting the primary endpoint. At the final analysis (data cutoff Nov 24, 2021), the most common grade 3-4 adverse events were neutropenia (29 [26%] of 112 in the giredestrant plus palbociclib group vs 29 [27%] of 109 in the anastrozole plus palbociclib group) and decreased neutrophil count (17 [15%] vs 16 [15%]). Serious adverse events occurred in five (4%) patients in the giredestrant plus palbociclib group and in two (2%) patients in the anastrozole plus palbociclib group. There were no treatment-related deaths. One patient died due to an adverse event in the giredestrant plus palbociclib group (myocardial infarction). INTERPRETATION: Giredestrant offers encouraging anti-proliferative and anti-tumour activity and was well tolerated, both as a single agent and in combination with palbociclib. Results justify further investigation in ongoing trials. FUNDING: F Hoffmann-La Roche.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Pessoa de Meia-Idade , Anastrozol , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Receptores de Estrogênio , Terapia Neoadjuvante/efeitos adversos , Antígeno Ki-67
4.
Inorg Chem ; 62(31): 12223-12236, 2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37503892

RESUMO

In the current research, we conducted a comparative study of the Ac3+ complex with H4DOTA and H4BATA. The stability constants of the [AcBATA]- and [AcDOTA]- complexes were studied directly by extraction methods. We discovered that the thermodynamic properties of the [AcBATA]- complex are superior to those of [AcDOTA]-. Moreover, the fast kinetics of H4BATA complexation with Ac3+ during the radiolabeling experiment was observed already at room temperature. Ac3+ was placed inside the macrocyclic cavity of the [AcBATA]- complex, preventing the release of the cation. According to DFT studies, two possible conformations were found, where two pendant arms coordinate with the metal cation on one side of the azacrown cavity and two on the other side, or three pendant arms are located on one side and one on the other. Finally, high inertness in vitro and in vivo of [AcBATA]- was discovered, making the H4BATA ligand highly preferable for application as a component of actinium-based radiopharmaceuticals.

5.
Molecules ; 28(8)2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-37110782

RESUMO

A radionuclide generator of the short-lived alpha emitter 226Th was proposed. An original scheme consisting of two in-series chromatographic columns was developed for rapidly producing a neutral citric-buffered eluate of high purity 226Th. The first column filled with TEVA resin retained the parent 230U, while 226Th was eluted with 7 M HCl solution to be immediately adsorbed on the second column containing DGA resin or UTEVA resin. Having substituted the strongly acidic medium of second column with neutral salt solution, 226Th was desorbed with diluted citric buffer solution. One cycle of generator milking took 5-7 min and produced >90% of 226Th in 1.5 mL of eluate (pH 4.5-5.0) appropriate for direct use in radiopharmaceutical synthesis. The 230U impurity in 226Th eluate was less than 0.01%. The proposed two-column 230U/226Th generator was tested over 2 months including a second loading of 230U additionally accumulated from 230Pa.

6.
Curr Radiopharm ; 16(3): 233-242, 2023 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-36809934

RESUMO

INTRODUCTION: The feasibility of preparing the "in-house" generators and the Th- DTPA(DOTA)-Nimotuzumab radioimmunoconjugate was evaluated. 226Th is perspective for TAT, however, due to short half-life it is preferable to apply this radionuclide for readily available epithelial malignancies. Nimotuzumab being specific for EGFR expressing cells as a targeting moiety is considered to be suitable for thorium delivery. METHODS: TEVA extraction chromatographic resin and anion exchange resin AG 1x8 were used as sorbents for 226Th generator. In order to determine features of labeling by Th4+ we applied 234Th as a longer-lived analog of short-lived 226Th and the immunoconjugates DTPA(DOTA)-Nimotuzumab were used for radiolabeling. RESULTS: The generator on the base of TEVA resin has shown higher volume activity of the product compared to the AG 1x8. The 226Th volume concentration was up to 80%/mL. The radiolabeling of BFCA by thorium radioisotopes reached 95% at the MR(Th:p-SCN-Bn-DTPA) = 1:100 and 86% for MR(Th:p-SCN-Bn-DOTA) = 1:5000 at 90°C. The procedure of Nimotuzumab labeling with Th4+ for radiotherapy of EGFR-overexpressing carcinomas was established. The overall labeling yield in both radioimmunoconjugates - DTPA and DOTA functionalized - was in the range of 45-50%. The immunoconjugate Nimotuzumab-p-SCN-Bn-DTPA was obtained with a molar ratio 1:25 (Nimotuzumab: BFCA), within 1 hour of conjugation at 25°C and labelled via postconjugation approach. Whereas Nimotuzumab-p-SCN-Bn-DOTA was obtained at the same conditions, but radiolabeled by the method of pre-conjugation. CONCLUSION: Thorium-234 incorporation into both radioimmunoconjugates reached 45-50%. It has been shown that Th-DTPA-Nimotuzumab radioimmunoconjugate specifically bound with EGFR overexpressing epidermoid carcinoma A431 cells.


Assuntos
Carcinoma , Imunoconjugados , Humanos , Radioimunoterapia/métodos , Tório , Compostos Radiofarmacêuticos , Radioisótopos , Imunoconjugados/química , Ácido Pentético , Receptores ErbB/metabolismo , Linhagem Celular Tumoral
7.
Nanomaterials (Basel) ; 12(19)2022 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-36234583

RESUMO

Convolutional neural networks (CNNs) have been widely used in image recognition and processing tasks. Memristor-based CNNs accumulate the advantages of emerging memristive devices, such as nanometer critical dimensions, low power consumption, and functional similarity to biological synapses. Most studies on memristor-based CNNs use either software models of memristors for simulation analysis or full hardware CNN realization. Here, we propose a hybrid CNN, consisting of a hardware fixed pre-trained and explainable feature extractor and a trainable software classifier. The hardware part was realized on passive crossbar arrays of memristors based on nanocomposite (Co-Fe-B)x(LiNbO3)100-x structures. The constructed 2-kernel CNN was able to classify the binarized Fashion-MNIST dataset with ~ 84% accuracy. The performance of the hybrid CNN is comparable to the other reported memristor-based systems, while the number of trainable parameters for the hybrid CNN is substantially lower. Moreover, the hybrid CNN is robust to the variations in the memristive characteristics: dispersion of 20% leads to only a 3% accuracy decrease. The obtained results pave the way for the efficient and reliable realization of neural networks based on partially unreliable analog elements.

8.
Pharmaceutics ; 13(6)2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-34205580

RESUMO

A new two-column 225Ac/213Bi generator was developed specifically for using 225Ac containing an impurity of long lived 227Ac. The parent 225Ac was retained on the first Actinide Resin column, while 213Bi was accumulated on the second column filled with AG MP-50 resin via continuous elution and decay of intermediate 221Fr. The 213Bi accumulation was realized in circulation mode which allowed a compact generator design. It was demonstrated that 213Bi could be quickly and effectively extracted from AG MP-50 in form of complexes with various chelating agents including DTPA and DOTA. The performance of the generator presented and a conventional single-column generator on the base of AG MP-50 was tested and both generators were loaded with 225Ac containing 227Ac impurity. The 213Bi generation efficiencies were comparable and greater than 70%, whereas the developed generator provided a deeper degree of purification of 213Bi from Ac isotopes and decay products of 227Ac.

9.
N Engl J Med ; 380(12): 1103-1115, 2019 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-30779531

RESUMO

BACKGROUND: In a single-group, phase 1b trial, avelumab plus axitinib resulted in objective responses in patients with advanced renal-cell carcinoma. This phase 3 trial involving previously untreated patients with advanced renal-cell carcinoma compared avelumab plus axitinib with the standard-of-care sunitinib. METHODS: We randomly assigned patients in a 1:1 ratio to receive avelumab (10 mg per kilogram of body weight) intravenously every 2 weeks plus axitinib (5 mg) orally twice daily or sunitinib (50 mg) orally once daily for 4 weeks (6-week cycle). The two independent primary end points were progression-free survival and overall survival among patients with programmed death ligand 1 (PD-L1)-positive tumors. A key secondary end point was progression-free survival in the overall population; other end points included objective response and safety. RESULTS: A total of 886 patients were assigned to receive avelumab plus axitinib (442 patients) or sunitinib (444 patients). Among the 560 patients with PD-L1-positive tumors (63.2%), the median progression-free survival was 13.8 months with avelumab plus axitinib, as compared with 7.2 months with sunitinib (hazard ratio for disease progression or death, 0.61; 95% confidence interval [CI], 0.47 to 0.79; P<0.001); in the overall population, the median progression-free survival was 13.8 months, as compared with 8.4 months (hazard ratio, 0.69; 95% CI, 0.56 to 0.84; P<0.001). Among the patients with PD-L1-positive tumors, the objective response rate was 55.2% with avelumab plus axitinib and 25.5% with sunitinib; at a median follow-up for overall survival of 11.6 months and 10.7 months in the two groups, 37 patients and 44 patients had died, respectively. Adverse events during treatment occurred in 99.5% of patients in the avelumab-plus-axitinib group and in 99.3% of patients in the sunitinib group; these events were grade 3 or higher in 71.2% and 71.5% of the patients in the respective groups. CONCLUSIONS: Progression-free survival was significantly longer with avelumab plus axitinib than with sunitinib among patients who received these agents as first-line treatment for advanced renal-cell carcinoma. (Funded by Pfizer and Merck [Darmstadt, Germany]; JAVELIN Renal 101 ClinicalTrials.gov number, NCT02684006.).


Assuntos
Anticorpos Monoclonais/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Axitinibe/administração & dosagem , Carcinoma de Células Renais/tratamento farmacológico , Neoplasias Renais/tratamento farmacológico , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Sunitinibe/uso terapêutico , Administração Intravenosa , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais Humanizados , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Axitinibe/efeitos adversos , Carcinoma de Células Renais/mortalidade , Feminino , Humanos , Neoplasias Renais/mortalidade , Masculino , Pessoa de Meia-Idade , Intervalo Livre de Progressão , Método Simples-Cego , Sunitinibe/efeitos adversos , Taxa de Sobrevida
10.
Dalton Trans ; 44(8): 3837-44, 2015 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-25611787

RESUMO

Low molecular weight organics (LMWO; e.g. acetate, propionate, lactate) can significantly impact the speciation and mobility of radionuclides in aqueous media. Natural clay rock formation, considered as a potential host rock for nuclear waste disposal, can contain a significant amount of organic matter. There are less thermodynamic data reported for the complexation of pentavalent actinides with LMWO, especially under elevated temperature conditions, relevant for assessing the long-term safety of disposal options for heat-producing high-level nuclear waste. In the present study, the complexation of Np(v) with propionate is studied using spectroscopic techniques in 0.5-4 M NaCl solutions by systematic variation of the ligand concentration and temperature. Slope analysis shows the formation of the 1 : 1 NpO2-propionate complex (NpO2Prop). The local structure of the NpO2-propionate complex is determined by extended X-ray absorption fine structure spectroscopy, the results of which suggest that propionate binds to Np(v) in a bidentate mode. Using the specific ion interaction theory (SIT), the stability constant at zero ionic strength and 25 °C is determined as log ß°1,1 = 1.26 ± 0.03. The stability constants increase continuously with increasing temperature between 20 and 85 °C. The log ß0 values are linearly correlated with the reciprocal temperature, indicating ΔrH = const. and ΔrC = 0, allowing the calculation of ΔrH and ΔrS for the formation of the NpO2-propionate complex using the integrated van't Hoff equation. The thermodynamic evaluation indicates that the reaction is endothermic and entropy driven.

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