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1.
Nat Commun ; 14(1): 5554, 2023 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-37689751

RESUMO

NEUROD1 is a transcription factor that helps maintain a mature phenotype of pancreatic ß cells. Disruption of Neurod1 during pancreatic development causes severe neonatal diabetes; however, the exact role of NEUROD1 in the differentiation programs of endocrine cells is unknown. Here, we report a crucial role of the NEUROD1 regulatory network in endocrine lineage commitment and differentiation. Mechanistically, transcriptome and chromatin landscape analyses demonstrate that Neurod1 inactivation triggers a downregulation of endocrine differentiation transcription factors and upregulation of non-endocrine genes within the Neurod1-deficient endocrine cell population, disturbing endocrine identity acquisition. Neurod1 deficiency altered the H3K27me3 histone modification pattern in promoter regions of differentially expressed genes, which resulted in gene regulatory network changes in the differentiation pathway of endocrine cells, compromising endocrine cell potential, differentiation, and functional properties.


Assuntos
Células Endócrinas , Células Secretoras de Insulina , Diferenciação Celular/genética , Fatores de Transcrição , Ativação Transcricional
2.
Ann Surg ; 278(4): 538-548, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37465976

RESUMO

OBJECTIVE: External exposures, the host, and the microbiome interact in oncology. We aimed to investigate tumoral microbiomes in young-onset rectal cancers (YORCs) for profiles potentially correlative with disease etiology and biology. BACKGROUND: YORC is rapidly increasing, with 1 in 4 new rectal cancer cases occurring under the age of 50 years. Its etiology is unknown. METHODS: YORC (<50 y old) or later-onset rectal cancer (LORC, ≥50 y old) patients underwent pretreatment biopsied of tumor and tumor-adjacent normal (TAN) tissue. After whole genome sequencing, metagenomic analysis quantified microbial communities comparing tumors versus TANs and YORCs versus LORCs, controlling for multiple testing. Response to neoadjuvant therapy (NT) was categorized as major pathological response (MPR, ≤10% residual viable tumor) versus non-MPR. RESULTS: Our 107 tumors, 75 TANs from 37 (35%) YORCs, and 70 (65%) LORCs recapitulated bacterial species were previously associated with colorectal cancers (all P <0.0001). YORC and LORC tumoral microbiome signatures were distinct. After NT, 13 patients (12.4%) achieved complete pathologic response, whereas MPR occurred in 47 patients (44%). Among YORCs, MPR was associated with Fusobacterium nucleaum , Bacteroides dorei, and Ruminococcus bromii (all P <0.001), but MPR in LORC was associated with R. bromii ( P <0.001). Network analysis of non-MPR tumors demonstrated a preponderance of oral bacteria not observed in MPR tumors. CONCLUSIONS: Microbial signatures were distinct between YORC and LORC. Failure to achieve an MPR was associated with oral bacteria in tumors. These findings urge further studies to decipher correlative versus mechanistic associations but suggest a potential for microbial modulation to augment current treatments.


Assuntos
Microbiota , Neoplasias Retais , Humanos , Pessoa de Meia-Idade , Terapia Neoadjuvante , Neoplasias Retais/terapia , Neoplasias Retais/patologia , Biópsia
3.
Islets ; 15(1): 2189873, 2023 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-36987915

RESUMO

We previously developed a deep learning-based web service (IsletNet) for an automated counting of isolated pancreatic islets. The neural network training is limited by the absent consensus on the ground truth annotations. Here, we present a platform (IsletSwipe) for an exchange of graphical opinions among experts to facilitate the consensus formation. The platform consists of a web interface and a mobile application. In a small pilot study, we demonstrate the functionalities and the use case scenarios of the platform. Nine experts from three centers validated the drawing tools, tested precision and consistency of the expert contour drawing, and evaluated user experience. Eight experts from two centers proceeded to evaluate additional images to demonstrate the following two use case scenarios. The Validation scenario involves an automated selection of images and islets for the expert scrutiny. It is scalable (more experts, images, and islets may readily be added) and can be applied to independent validation of islet contours from various sources. The Inquiry scenario serves the ground truth generating expert in seeking assistance from peers to achieve consensus on challenging cases during the preparation for IsletNet training. This scenario is limited to a small number of manually selected images and islets. The experts gained an opportunity to influence IsletNet training and to compare other experts' opinions with their own. The ground truth-generating expert obtained feedback for future IsletNet training. IsletSwipe is a suitable tool for the consensus finding. Experts from additional centers are welcome to participate.


Assuntos
Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas , Prova Pericial , Projetos Piloto , Transplante das Ilhotas Pancreáticas/métodos , Redes Neurais de Computação
4.
Cell Biosci ; 13(1): 53, 2023 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-36899442

RESUMO

BACKGROUND: Glucose homeostasis is dependent on functional pancreatic α and ß cells. The mechanisms underlying the generation and maturation of these endocrine cells remain unclear. RESULTS: We unravel the molecular mode of action of ISL1 in controlling α cell fate and the formation of functional ß cells in the pancreas. By combining transgenic mouse models, transcriptomic and epigenomic profiling, we uncover that elimination of Isl1 results in a diabetic phenotype with a complete loss of α cells, disrupted pancreatic islet architecture, downregulation of key ß-cell regulators and maturation markers of ß cells, and an enrichment in an intermediate endocrine progenitor transcriptomic profile. CONCLUSIONS: Mechanistically, apart from the altered transcriptome of pancreatic endocrine cells, Isl1 elimination results in altered silencing H3K27me3 histone modifications in the promoter regions of genes that are essential for endocrine cell differentiation. Our results thus show that ISL1 transcriptionally and epigenetically controls α cell fate competence, and ß cell maturation, suggesting that ISL1 is a critical component for generating functional α and ß cells.

5.
J Funct Biomater ; 13(4)2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-36278640

RESUMO

Infusing pancreatic islets into the portal vein currently represents the preferred approach for islet transplantation, despite considerable loss of islet mass almost immediately after implantation. Therefore, approaches that obviate direct intravascular placement are urgently needed. A promising candidate for extrahepatic placement is the omentum. We aimed to develop an extracellular matrix skeleton from the native pancreas that could provide a microenvironment for islet survival in an omental flap. To that end, we compared different decellularization approaches, including perfusion through the pancreatic duct, gastric artery, portal vein, and a novel method through the splenic vein. Decellularized skeletons were compared for size, residual DNA content, protein composition, histology, electron microscopy, and MR imaging after repopulation with isolated islets. Compared to the other approaches, pancreatic perfusion via the splenic vein provided smaller extracellular matrix skeletons, which facilitated transplantation into the omentum, without compromising other requirements, such as the complete depletion of cellular components and the preservation of pancreatic extracellular proteins. Repeated MR imaging of iron-oxide-labeled pancreatic islets showed that islets maintained their position in vivo for 49 days. Advanced environmental scanning electron microscopy demonstrated that islets remained integrated with the pancreatic skeleton. This novel approach represents a proof-of-concept for long-term transplantation experiments.

6.
ACS Appl Mater Interfaces ; 14(16): 18233-18247, 2022 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-35416039

RESUMO

Novel Yb,Tb,Nd-doped GdF3 and NaGdF4 nanoparticles were synthesized by a coprecipitation method in ethylene glycol (EG) in the presence of the poly(4-styrenesulfonic acid-co-maleic anhydride) stabilizer. The particle size and morphology, crystal structure, and phase change were controlled by adjusting the PSSMA concentration and source of fluoride anions in the reaction. Doping of Yb3+, Tb3+, and Nd3+ ions in the NaGdF4 host nanoparticles induced luminescence under ultraviolet and near-infrared excitation and high relaxivity in magnetic resonance (MR) imaging (MRI). In vitro toxicity of the nanoparticles and their cellular uptake efficiency were determined in model rat pancreatic ß-cells (INS-1E). As the NaGdF4:Yb,Tb,Nd@PSSMA-EG nanoparticles were non-toxic and possessed good luminescence and magnetic properties, they were applicable for in vitro optical and MRI of isolated pancreatic islets in phantoms. The superior contrast was achieved for in vivo T2*-weighted MR images of the islets transplanted under the kidney capsule to mice in preclinical trials.


Assuntos
Ilhotas Pancreáticas , Nanopartículas , Animais , Ilhotas Pancreáticas/diagnóstico por imagem , Luminescência , Imageamento por Ressonância Magnética/métodos , Anidridos Maleicos , Camundongos , Nanopartículas/química , Ratos
7.
Transplant Proc ; 54(3): 806-810, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35227510

RESUMO

BACKGROUND: Islet transplantation represents an established therapeutic option for people with type 1 diabetes who have hypoglycemia unawareness syndrome and frequent problematic hypoglycemic episodes when other methods comprising diabetes education and use of technological support fail. Because the current standard method of islet infusion into the liver has some limitations, novel approaches are under investigation. METHODS: We report our first results with 2 cases of islet transplantation into an omental pouch using a biocompatible plasma-fibrin gel. The recipients received 12,350 and 5,350 islet equivalents per kilogram that were mixed with autologous plasma, seeded during a laparoscopic procedure on the omentum, overlaid with human thrombin solution, and fixed by flapping the omentum over. RESULTS: During a 9-month follow-up, neither patient experienced any moderate or severe hypoglycemia. Their glucose control significantly improved, insulin dose decreased by approximately 50%, and C-peptide at 1 year was 0.22 and 0.14 pmol/mL, respectively. The postoperative course was uneventful, but C-peptide production in the first patient progressively declined at 1 year and hypoglycemic episodes recurred. CONCLUSIONS: Though the results for these first 2 cases are not fully satisfactory, we have demonstrated the feasibility, safety, and ability of this novel method to restore insulin production. Further refinements to improve immediate islet survival seem necessary.


Assuntos
Pesquisa Biomédica , Diabetes Mellitus Tipo 1 , Hipoglicemia , Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas , Glicemia , Peptídeo C , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/cirurgia , Humanos , Hipoglicemia/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Transplante das Ilhotas Pancreáticas/efeitos adversos , Transplante das Ilhotas Pancreáticas/métodos , Omento/cirurgia , Trombina/uso terapêutico
8.
Transplantation ; 106(3): 531-542, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-34086655

RESUMO

BACKGROUND: Transplantation of pancreatic islets into subcutaneous cavities in diabetic rats may be as or even more effective than transplantation into the portal vein. Identifying the optimal timing of the individual steps in this procedure is critical. METHODS: Macroporous scaffolds were placed in the subcutaneous tissue of diabetic male Lewis rats for 7 or 28 d and the healing of the tissue inside the scaffolds was monitored. A marginal syngeneic graft comprising 4 islets/g of recipient body weight was transplanted at the best timing focusing mainly on vascularization. Recipients were monitored for blood glucose levels and tolerance tests. Histological examination was performed in all implanted scaffolds. The presence of individual endocrine cells was analyzed in detail. RESULTS: Blood glucose levels remained within the physiological range in all recipients until the end of experiment as well as body weight increase. Coefficients of glucose assimilation were normal or slightly reduced with no statistically significant differences between the groups 40 and 80 d after transplantation. Histological analysis revealed round viable islets in the liver similar to those in pancreas, but alpha cells practically disappeared, whereas islets in the scaffolds formed clusters of cells surrounded by rich vascular network and the alpha cells remained partially preserved. CONCLUSIONS: Subcutaneous transplantation of pancreatic islets is considerably less invasive but comparably efficient as commonly used islet transplantation into the portal vein. In consideration of alpha and beta cell ratio, the artificial subcutaneous cavities represent a promising site for future islet transplantation therapy.


Assuntos
Diabetes Mellitus Experimental , Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas , Animais , Glicemia , Diabetes Mellitus Experimental/cirurgia , Ilhotas Pancreáticas/irrigação sanguínea , Ilhotas Pancreáticas/cirurgia , Transplante das Ilhotas Pancreáticas/métodos , Masculino , Ratos , Ratos Endogâmicos Lew , Tela Subcutânea
9.
Int J Mol Sci ; 22(13)2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34201511

RESUMO

Diabetes is a metabolic disease that involves the death or dysfunction of the insulin-secreting ß cells in the pancreas. Consequently, most diabetes research is aimed at understanding the molecular and cellular bases of pancreatic development, islet formation, ß-cell survival, and insulin secretion. Complex interactions of signaling pathways and transcription factor networks regulate the specification, growth, and differentiation of cell types in the developing pancreas. Many of the same regulators continue to modulate gene expression and cell fate of the adult pancreas. The transcription factor NEUROD1 is essential for the maturation of ß cells and the expansion of the pancreatic islet cell mass. Mutations of the Neurod1 gene cause diabetes in humans and mice. However, the different aspects of the requirement of NEUROD1 for pancreas development are not fully understood. In this study, we investigated the role of NEUROD1 during the primary and secondary transitions of mouse pancreas development. We determined that the elimination of Neurod1 impairs the expression of key transcription factors for α- and ß-cell differentiation, ß-cell proliferation, insulin production, and islets of Langerhans formation. These findings demonstrate that the Neurod1 deletion altered the properties of α and ß endocrine cells, resulting in severe neonatal diabetes, and thus, NEUROD1 is required for proper activation of the transcriptional network and differentiation of functional α and ß cells.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Ilhotas Pancreáticas/citologia , Pâncreas/citologia , Pâncreas/embriologia , Animais , Animais Recém-Nascidos , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Diferenciação Celular , Linhagem da Célula , Proliferação de Células , Diabetes Mellitus/genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Insulina/metabolismo , Células Secretoras de Insulina/citologia , Células Secretoras de Insulina/metabolismo , Ilhotas Pancreáticas/metabolismo , Ilhotas Pancreáticas/ultraestrutura , Camundongos Endogâmicos C57BL , Camundongos Transgênicos
10.
Mol Imaging Biol ; 23(5): 639-649, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33599904

RESUMO

PURPOSE: The liver is the most widely used site for pancreatic islet transplantation. However, several site-specific limitations impair functional success, with instant blood-mediated inflammatory reaction being the most important. The aim of this study was to develop a preclinical model for placement of the islet graft into a highly vascularized omental flap using a fibrin gel. For this purpose, we tested islet viability by bioluminescence imaging (BLI). PROCEDURES: Pancreatic islets were isolated from luciferase-positive and luciferase-negative rats, mixed at a 1:1 ratio, placed into a plasma-thrombin bioscaffold, and transplanted in standard (10 pancreatic islets/g wt; n = 10) and marginal (4 pancreatic islets/g wt; n = 7) numbers into the omentums of syngeneic diabetic animals. For the control, 4 pancreatic islets/g were transplanted into the liver using the standard procedure (n = 7). Graft viability was tested by bioluminescence at days 14, 30, 60, and 90 post transplant. Glucose levels, intravenous glucose tolerance, and serum C-peptide were assessed regularly. RESULTS: Nonfasting glucose levels < 10 mmol/l were restored in all animals. While islet viability in the omentum was clearly detected by stable luminescence signals throughout the whole study period, no signals were detected from islets transplanted into the liver. The bioluminescence signals were highly correlated with stimulated C-peptide levels detected at 80 days post transplant. Glucose tolerance did not differ among the 3 groups. CONCLUSIONS: We successfully tested a preclinical model of islet transplantation into the greater omentum using a biocompatible scaffold made from autologous plasma and human thrombin. Both standard and marginal pancreatic islet numbers in a gel-form bioscaffold placed in the omentum restored glucose homeostasis in recipients with diabetes. Bioluminescence was shown promising as a direct proof of islet viability.


Assuntos
Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas/diagnóstico por imagem , Medições Luminescentes/métodos , Imagem Molecular/métodos , Omento/diagnóstico por imagem , Animais , Sobrevivência Celular/fisiologia , Feminino , Sobrevivência de Enxerto/fisiologia , Masculino , Ratos
13.
Proc Natl Acad Sci U S A ; 117(33): 20004-20014, 2020 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-32747568

RESUMO

KRAS, NRAS, and BRAF mutations which activate p44/42 mitogen-activated protein kinase (MAPK) signaling are found in half of myeloma patients and contribute to proteasome inhibitor (PI) resistance, but the underlying mechanisms are not fully understood. We established myeloma cell lines expressing wild-type (WT), constitutively active (CA) (G12V/G13D/Q61H), or dominant-negative (DN) (S17N)-KRAS and -NRAS, or BRAF-V600E. Cells expressing CA mutants showed increased proteasome maturation protein (POMP) and nuclear factor (erythroid-derived 2)-like 2 (NRF2) expression. This correlated with an increase in catalytically active proteasome subunit ß (PSMB)-8, PSMB9, and PSMB10, which occurred in an ETS transcription factor-dependent manner. Proteasome chymotrypsin-like, trypsin-like, and caspase-like activities were increased, and this enhanced capacity reduced PI sensitivity, while DN-KRAS and DN-NRAS did the opposite. Pharmacologic RAF or MAPK kinase (MEK) inhibitors decreased proteasome activity, and sensitized myeloma cells to PIs. CA-KRAS, CA-NRAS, and CA-BRAF down-regulated expression of endoplasmic reticulum (ER) stress proteins, and reduced unfolded protein response activation, while DN mutations increased both. Finally, a bortezomib (BTZ)/MEK inhibitor combination showed enhanced activity in vivo specifically in CA-NRAS models. Taken together, the data support the hypothesis that activating MAPK pathway mutations enhance PI resistance by increasing proteasome capacity, and provide a rationale for targeting such patients with PI/RAF or PI/MEK inhibitor combinations. Moreover, they argue these mutations promote myeloma survival by reducing cellular stress, thereby distancing plasma cells from the apoptotic threshold, potentially explaining their high frequency in myeloma.


Assuntos
Estresse do Retículo Endoplasmático , GTP Fosfo-Hidrolases/metabolismo , Proteínas de Membrana/metabolismo , Mieloma Múltiplo/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas Proto-Oncogênicas B-raf/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Apoptose/efeitos dos fármacos , Bortezomib/farmacologia , Estresse do Retículo Endoplasmático/efeitos dos fármacos , GTP Fosfo-Hidrolases/genética , Humanos , Proteínas de Membrana/genética , Mieloma Múltiplo/genética , Mieloma Múltiplo/fisiopatologia , Mutação , Complexo de Endopeptidases do Proteassoma/genética , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras)/genética
15.
Diabetes ; 69(7): 1341-1354, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32245800

RESUMO

NADPH facilitates glucose-stimulated insulin secretion (GSIS) in pancreatic islets (PIs) of ß-cells through an as yet unknown mechanism. We found NADPH oxidase isoform 4 (NOX4) to be the main producer of cytosolic H2O2, which is essential for GSIS; an increase in ATP alone was insufficient for GSIS. The fast GSIS phase was absent from PIs from NOX4-null, ß-cell-specific knockout mice (NOX4ßKO) (though not from NOX2 knockout mice) and from NOX4-silenced or catalase-overexpressing INS-1E cells. Lentiviral NOX4 overexpression or H2O2 rescued GSIS in PIs from NOX4ßKO mice. NOX4 silencing suppressed Ca2+ oscillations, and the patch-clamped KATP channel opened more frequently when glucose was high. Mitochondrial H2O2, decreasing upon GSIS, provided alternative redox signaling when 2-oxo-isocaproate or fatty acid oxidation formed superoxides through electron-transfer flavoprotein:Q-oxidoreductase. Unlike GSIS, such insulin secretion was blocked with mitochondrial antioxidant SkQ1. Both NOX4 knockout and NOX4ßKO mice exhibited impaired glucose tolerance and peripheral insulin resistance. Thus, the redox signaling previously suggested to cause ß-cells to self-check hypothetically induces insulin resistance when it is absent. In conclusion, increases in ATP and H2O2 constitute an essential signal that switches on insulin exocytosis for glucose and branched-chain oxoacids as secretagogues (it does so partially for fatty acids). Redox signaling could be impaired by cytosolic antioxidants; hence, those targeting mitochondria should be preferred for clinical applications to treat (pre)diabetes at any stage.


Assuntos
Glucose/farmacologia , Peróxido de Hidrogênio/metabolismo , Secreção de Insulina , NADPH Oxidase 4/fisiologia , Animais , Cálcio/metabolismo , Células Cultivadas , Resistência à Insulina , Camundongos , Camundongos Endogâmicos C57BL , Canais de Potássio/fisiologia , Transdução de Sinais/fisiologia
17.
Sci Rep ; 9(1): 19097, 2019 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-31836843

RESUMO

Parenteral nutrition (PN) is often associated with the deterioration of liver functions (PNALD). Omega-3 polyunsaturated fatty acids (PUFA) were reported to alleviate PNALD but the underlying mechanisms have not been fully unraveled yet. Using omics´ approach, we determined serum and liver lipidome, liver proteome, and liver bile acid profile as well as markers of inflammation and oxidative stress in rats administered either ω-6 PUFA based lipid emulsion (Intralipid) or ω-6/ω-3 PUFA blend (Intralipid/Omegaven) via the enteral or parenteral route. In general, we found that enteral administration of both lipid emulsions has less impact on the liver than the parenteral route. Compared with parenterally administered Intralipid, PN administration of ω-3 PUFA was associated with 1. increased content of eicosapentaenoic (EPA)- and docosahexaenoic (DHA) acids-containing lipid species; 2. higher abundance of CYP4A isoenzymes capable of bioactive lipid synthesis and the increased content of their potential products (oxidized EPA and DHA); 3. downregulation of enzymes involved CYP450 drug metabolism what may represent an adaptive mechanism counteracting the potential negative effects (enhanced ROS production) of PUFA metabolism; 4. normalized anti-oxidative capacity and 5. physiological BAs spectrum. All these findings may contribute to the explanation of ω-3 PUFA protective effects in the context of PN.


Assuntos
Ácidos e Sais Biliares/análise , Nutrição Enteral/métodos , Ácidos Graxos Ômega-3/química , Fígado/metabolismo , Nutrição Parenteral/métodos , Proteoma/metabolismo , Animais , Ácidos Docosa-Hexaenoicos/química , Ácido Eicosapentaenoico/química , Emulsões , Ácidos Graxos Insaturados/metabolismo , Óleos de Peixe , Inflamação , Lipidômica , Lipídeos/química , Masculino , Malondialdeído/metabolismo , Metabolômica , Estresse Oxidativo , Oxigênio/metabolismo , Fosfolipídeos , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Óleo de Soja
18.
Blood Adv ; 3(15): 2400-2408, 2019 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-31405950

RESUMO

Multiple myeloma is, in most patients, an incurable cancer. Its precursors can be identified with routine tests setting the stage for early intervention to prevent active myeloma. We investigated the efficacy and safety of pembrolizumab, an antiprogrammed cell death 1 antibody, in smoldering myeloma patients with intermediate/high risk of progression to symptomatic myeloma. Thirteen patients were treated with a median number of 8 cycles. One patient achieved a stringent complete response with bone marrow next-generation sequencing negativity at 10-4 that is ongoing at 27 months (8%); 11 had stable disease (85%), and 1 progressed (8%). Three patients discontinued therapy due to immune-related adverse events: 2 with transaminitis and 1 due to tubulointerstitial nephritis. Immune profiling of bone marrow samples at baseline showed markers associated with a preexisting immune response in the responder compared with nonresponders and features of increased T-cell exhaustion in nonresponders. Consistent with this, transcriptome sequencing of bone marrow samples at baseline revealed an increased interferon-γ signature in the responder compared with the nonresponders. In summary, our results suggest that smoldering myeloma may be immunogenic in a subset of patients, and therapies that enhance antitumor T-cell responses may be effective in preventing its progression. This trial was registered at www.clinicaltrials.gov as #NCT02603887.

19.
Blood ; 133(14): 1572-1584, 2019 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-30737236

RESUMO

Three proteasome inhibitors have garnered regulatory approvals in various multiple myeloma settings; but drug resistance is an emerging challenge, prompting interest in blocking upstream components of the ubiquitin-proteasome pathway. One such attractive target is the E1 ubiquitin-activating enzyme (UAE); we therefore evaluated the activity of TAK-243, a novel and specific UAE inhibitor. TAK-243 potently suppressed myeloma cell line growth, induced apoptosis, and activated caspases while decreasing the abundance of ubiquitin-protein conjugates. This was accompanied by stabilization of many short-lived proteins, including p53, myeloid cell leukemia 1 (MCL-1), and c-MYC, and activation of the activating transcription factor 6 (ATF-6), inositol-requiring enzyme 1 (IRE-1), and protein kinase RNA-like endoplasmic reticulum (ER) kinase (PERK) arms of the ER stress response pathway, as well as oxidative stress. UAE inhibition showed comparable activity against otherwise isogenic cell lines with wild-type (WT) or deleted p53 despite induction of TP53 signaling in WT cells. Notably, TAK-243 overcame resistance to conventional drugs and novel agents in cell-line models, including bortezomib and carfilzomib resistance, and showed activity against primary cells from relapsed/refractory myeloma patients. In addition, TAK-243 showed strong synergy with a number of antimyeloma agents, including doxorubicin, melphalan, and panobinostat as measured by low combination indices. Finally, TAK-243 was active against a number of in vivo myeloma models in association with activation of ER stress. Taken together, the data support the conclusion that UAE inhibition could be an attractive strategy to move forward to the clinic for patients with relapsed and/or refractory multiple myeloma.


Assuntos
Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Mieloma Múltiplo/tratamento farmacológico , Inibidores de Proteassoma/farmacologia , Enzimas Ativadoras de Ubiquitina/antagonistas & inibidores , Resposta a Proteínas não Dobradas/efeitos dos fármacos , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Sinergismo Farmacológico , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Humanos , Estresse Oxidativo/efeitos dos fármacos , Terapia de Salvação/métodos , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53/efeitos dos fármacos , Proteína Supressora de Tumor p53/metabolismo
20.
Lancet Haematol ; 5(12): e628-e640, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30501870

RESUMO

BACKGROUND: Bortezomib with lenalidomide and dexamethasone (VRd) is a standard regimen for the front-line treatment of multiple myeloma. Panobinostat is approved in combination with bortezomib and dexamethasone in patients with myeloma who 'have been given at least two previous regimens including bortezomib and an immunomodulatory agent. We aimed to determine the maximum tolerated dose of a new regimen combining VRd with panobinostat in patients with newly diagnosed multiple myeloma. METHODS: In this phase 1 study, we enrolled patients from the University of Texas MD Anderson Cancer Center (Houston, TX, USA) with newly diagnosed multiple myeloma who were aged 18 years or older and eligible for autologous stem-cell transplant (ASCT) according to International Myeloma Working Group 2014 diagnostic criteria. Participants were allocated either to the dose-escalation cohort or the dose-expansion cohort. In the dose-escalation cohort, in a 3 + 3 design, patients were treated in cycles of 21 days with bortezomib (1·3 mg/m2, subcutaneously) on days 1, 4, 8, 11; lenalidomide (25 mg, orally) on days 1-14; dexamethasone (20 mg, orally) on days 1, 2, 4, 5, 8, 9, 11, and 12; and escalating doses of panobinostat (10-20 mg, orally) on days 1, 3, 5, 8, 10, and 12. The dose level exceeded the maximum tolerated dose if at any given dose more than one of three patients, or two of six patients, had a dose-limiting toxic event. In the dose-expansion cohort, patients were given the maximum tolerated dose of the drug combination as determined from the dose-escalation cohort. Patients could proceed with upfront ASCT after two to four cycles of initial therapy or store their stem cells and proceed with a delayed ASCT approach. Patients with delayed ASCT could continue therapy for up to eight cycles, followed by maintenance with lenalidomide, dexamethasone, and panobinostat at their last tolerated dose for up to 2 years. The primary objective was to determine the maximum tolerated dose of VRd with panobinostat. Safety was assessed in all patients who completed at least one cycle of therapy. This trial is registered with ClinicalTrials.gov, number NCT01440582, and is no longer recruiting participants. FINDINGS: Between Feb 18, 2013, and June 8, 2016, 55 patients were identified as eligible for enrolment. The dose-escalation cohort comprised 12 participants. The first three (25%) patients at dose level 1 (panobinostat 10 mg) did not encounter dose-limiting toxicity. Of six (50%) patients at dose level 2 (panobinostat 15 mg), two (33%) had dose-limiting toxic events during cycle 1; one (17%) had grade 4 thrombocytopenia with bleeding and the other had grade 3 diarrhoea, thus exceeding the maximum tolerated dose. Because the maximum tolerated dose had been exceeded, three more patients were accrued to dose level 1 and these patients did not experience dose-limiting toxic events. Dose level 1 (21 day cycles of bortezomib 1·3 mg/m2 subcutaneously on days 1, 4, 8, 11; lenalidomide 25 mg orally on days 1-14; dexamethasone 20 mg orally on days 1, 2, 4, 5, 8, 9, 11, 12; and panobinostat 10 mg orally on days 1, 3, 5, 8, 10 and 12) was established as the maximum tolerated dose. INTERPRETATION: The combination of VRd with panobinostat 10 mg is safe and effective in patients who are newly diagnosed with multiple myeloma and who are transplant eligible. Further studies in large randomised controlled settings are needed to confirm these results. FUNDING: Novartis and MD Anderson Cancer Center Support Grant.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Transplante de Células-Tronco Hematopoéticas , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/cirurgia , Adulto , Idoso , Bortezomib/efeitos adversos , Bortezomib/uso terapêutico , Dexametasona/efeitos adversos , Dexametasona/uso terapêutico , Definição da Elegibilidade , Feminino , Humanos , Estimativa de Kaplan-Meier , Lenalidomida/efeitos adversos , Lenalidomida/uso terapêutico , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Panobinostat/efeitos adversos , Panobinostat/uso terapêutico , Transplante Autólogo
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