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1.
Ann Biomed Eng ; 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38977529

RESUMO

PURPOSE: Individual facial soft tissue properties are necessary for creating individualized finite element (FE) models to evaluate medical devices such as continuous positive airway pressure (CPAP) masks. There are no standard tools available to measure facial soft tissue elastic moduli, and techniques in literature require advanced equipment or custom parts to replicate. METHODS: We propose a simple and inexpensive soft tissue measurement (STM) indenter device to estimate facial soft tissue elasticity at five sites: chin, cheek near lip, below cheekbone, cheekbone, and cheek. The STM device consists of a probe with a linear actuator and force sensor, an adjustment system for probe orientation, a head support frame, and a controller. The device was validated on six ballistics gel samples and then tested on 28 subjects. Soft tissue thickness was also collected for each subject using ultrasound. RESULTS: Thickness and elastic modulus measurements were successfully collected for all subjects. The mean elastic modulus for each site is Ec = 53.04 ± 20.97 kPa for the chin, El = 16.33 ± 8.37 kPa for the cheek near lip, Ebc = 27.09 ± 11.38 kPa for below cheekbone, Ecb = 64.79 ± 17.12 kPa for the cheekbone, and Ech = 16.20 ± 5.09 kPa for the cheek. The thickness and elastic modulus values are in the range of previously reported values. One subject's measured soft tissue elastic moduli and thickness were used to evaluate custom-fit CPAP mask fit in comparison to a model of that subject with arbitrary elastic moduli and thickness. The model with measured values more closely resembles in vivo leakage results. CONCLUSION: Overall, the STM provides a first estimate of facial soft tissue elasticity and is affordable and easy to build with mostly off-the-shelf parts. These values can be used to create personalized FE models to evaluate custom-fit CPAP masks.

2.
Cancer Res Commun ; 4(5): 1328-1343, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38687198

RESUMO

Chronic lymphocytic leukemia (CLL) cell survival and growth is fueled by the induction of B-cell receptor (BCR) signaling within the tumor microenvironment (TME) driving activation of NFκB signaling and the unfolded protein response (UPR). Malignant cells have higher basal levels of UPR posing a unique therapeutic window to combat CLL cell growth using pharmacologic agents that induce accumulation of misfolded proteins. Frontline CLL therapeutics that directly target BCR signaling such as Bruton tyrosine kinase (BTK) inhibitors (e.g., ibrutinib) have enhanced patient survival. However, resistance mechanisms wherein tumor cells bypass BTK inhibition through acquired BTK mutations, and/or activation of alternative survival mechanisms have rendered ibrutinib ineffective, imposing the need for novel therapeutics. We evaluated SpiD3, a novel spirocyclic dimer, in CLL cell lines, patient-derived CLL samples, ibrutinib-resistant CLL cells, and in the Eµ-TCL1 mouse model. Our integrated multi-omics and functional analyses revealed BCR signaling, NFκB signaling, and endoplasmic reticulum stress among the top pathways modulated by SpiD3. This was accompanied by marked upregulation of the UPR and inhibition of global protein synthesis in CLL cell lines and patient-derived CLL cells. In ibrutinib-resistant CLL cells, SpiD3 retained its antileukemic effects, mirrored in reduced activation of key proliferative pathways (e.g., PRAS, ERK, MYC). Translationally, we observed reduced tumor burden in SpiD3-treated Eµ-TCL1 mice. Our findings reveal that SpiD3 exploits critical vulnerabilities in CLL cells including NFκB signaling and the UPR, culminating in profound antitumor properties independent of TME stimuli. SIGNIFICANCE: SpiD3 demonstrates cytotoxicity in CLL partially through inhibition of NFκB signaling independent of tumor-supportive stimuli. By inducing the accumulation of unfolded proteins, SpiD3 activates the UPR and hinders protein synthesis in CLL cells. Overall, SpiD3 exploits critical CLL vulnerabilities (i.e., the NFκB pathway and UPR) highlighting its use in drug-resistant CLL.


Assuntos
Leucemia Linfocítica Crônica de Células B , Transdução de Sinais , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/metabolismo , Leucemia Linfocítica Crônica de Células B/patologia , Humanos , Animais , Camundongos , Transdução de Sinais/efeitos dos fármacos , Piperidinas/farmacologia , Piperidinas/uso terapêutico , Linhagem Celular Tumoral , Resposta a Proteínas não Dobradas/efeitos dos fármacos , Adenina/análogos & derivados , Adenina/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , NF-kappa B/metabolismo , Compostos de Espiro/farmacologia , Compostos de Espiro/uso terapêutico , Sobrevivência Celular/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacos , Receptores de Antígenos de Linfócitos B/metabolismo , Proliferação de Células/efeitos dos fármacos
3.
Artigo em Inglês | MEDLINE | ID: mdl-38607946

RESUMO

Continuous Positive Airway Pressure (CPAP) is a common therapy used to treat breathing disorders such as obstructive sleep apnea. In previous work, we designed a custom-fit CPAP mask to address comfort and leakage issues patients often experience. This paper presents a method to create a finite element (FE) model to evaluate the fit of the custom-fit mask before fabrication. The model includes details such as a skull to represent the variable soft tissue thicknesses on the face, and two strap configurations, original and X. The model was tested on four subjects and results show that the X strap configuration results in a more even stress distribution, measured by standard deviation, on the face compared to the original strap, indicating better fit. The simulations also show gaps in the stress distribution that seem to correspond to areas of leakage based on two initial in vivo tests on two subjects. This simulation method proves to be a valuable tool for custom-fit mask development by allowing us to evaluate designs before fabrication.

5.
ACS Omega ; 9(9): 9974-9990, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38463282

RESUMO

Gum ghatti, popularly known as Indian gum and obtained from Anogeissus latifolia, is a complex high-molecular-weight, water-soluble, and swellable nonstarch polysaccharide comprised of magnesium and calcium salts of ghattic acids and multiple monosugars. Unlike other nontimber forest produce, gums ghatti is a low-volume but high-value product. It has several applications and is widely used as food, in pharmaceuticals, and for wastewater treatment and hydrogel formation, and it has attracted a great deal of attention in the fields of energy, environmental science, and nanotechnology. Industrial applications of gum ghatti are primarily due to its excellent emulsification, stabilization, thickening, heat tolerance, pH stability, carrier, and biodegradable properties. However, utilization of gum ghatti is poorly explored and implemented due to a lack of knowledge of its production, processing, and properties. Nevertheless, there has been interest among investigators in recent times for exploring its production, processing, molecular skeleton, and functional properties. This present review focuses on production scenarios, processing aspects, structural and functional properties, and potential applications in the food, pharmaceuticals, nonfood, and other indigenous and industrial usages.

6.
Nat Cell Biol ; 26(4): 613-627, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38429478

RESUMO

The ability of tumour cells to thrive in harsh microenvironments depends on the utilization of nutrients available in the milieu. Here we show that pancreatic cancer-associated fibroblasts (CAFs) regulate tumour cell metabolism through the secretion of acetate, which can be blocked by silencing ATP citrate lyase (ACLY) in CAFs. We further show that acetyl-CoA synthetase short-chain family member 2 (ACSS2) channels the exogenous acetate to regulate the dynamic cancer epigenome and transcriptome, thereby facilitating cancer cell survival in an acidic microenvironment. Comparative H3K27ac ChIP-seq and RNA-seq analyses revealed alterations in polyamine homeostasis through regulation of SAT1 gene expression and enrichment of the SP1-responsive signature. We identified acetate/ACSS2-mediated acetylation of SP1 at the lysine 19 residue that increased SP1 protein stability and transcriptional activity. Genetic or pharmacologic inhibition of the ACSS2-SP1-SAT1 axis diminished the tumour burden in mouse models. These results reveal that the metabolic flexibility imparted by the stroma-derived acetate enabled cancer cell survival under acidosis via the ACSS2-SP1-SAT1 axis.


Assuntos
Fibroblastos Associados a Câncer , Neoplasias Pancreáticas , Animais , Camundongos , Fibroblastos Associados a Câncer/metabolismo , Linhagem Celular Tumoral , Acetatos/farmacologia , Acetatos/metabolismo , Neoplasias Pancreáticas/genética , Poliaminas , Microambiente Tumoral
7.
Cell Chem Biol ; 31(2): 221-233.e14, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-37875111

RESUMO

Methotrexate (MTX) is a tight-binding dihydrofolate reductase (DHFR) inhibitor, used as both an antineoplastic and immunosuppressant therapeutic. MTX, like folate undergoes folylpolyglutamate synthetase-mediated γ-glutamylation, which affects cellular retention and target specificity. Mechanisms of MTX resistance in cancers include a decrease in MTX poly-γ-glutamylation and an upregulation of DHFR. Here, we report a series of potent MTX-based proteolysis targeting chimeras (PROTACs) to investigate DHFR degradation pharmacology and one-carbon biochemistry. These on-target, cell-active PROTACs show proteasome- and E3 ligase-dependent activity, and selective degradation of DHFR in multiple cancer cell lines. By comparison, treatment with MTX increases cellular DHFR protein expression. Importantly, these PROTACs produced distinct, less-lethal phenotypes compared to MTX. The chemical probe set described here should complement conventional DHFR inhibitors and serve as useful tools for studying one-carbon biochemistry and dissecting complex polypharmacology of MTX and related drugs. Such compounds may also serve as leads for potential autoimmune and antineoplastic therapeutics.


Assuntos
Antineoplásicos , Antagonistas do Ácido Fólico , Neoplasias , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Carbono , Antagonistas do Ácido Fólico/química , Antagonistas do Ácido Fólico/metabolismo , Antagonistas do Ácido Fólico/farmacologia , Antagonistas do Ácido Fólico/uso terapêutico , Metotrexato/farmacologia , Metotrexato/metabolismo , Metotrexato/uso terapêutico , Neoplasias/tratamento farmacológico , Quimera de Direcionamento de Proteólise , Tetra-Hidrofolato Desidrogenase/metabolismo
8.
J Psychosom Obstet Gynaecol ; 44(1): 2278016, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-38050938

RESUMO

Postpartum depression (PPD) is classified under postpartum psychiatric disorders and initiates soon after birthing, eliciting neuropsychological and behavioral deficits in mothers and offspring. Globally, PPD is estimated to be associated with 130-190 per 1000 birthing. The severity and incidences of PPD have aggravated in the recent years due to the several unfavorable environmental and geopolitical circumstances. The purpose of this systematic review hence is to explore the contributions of recent circumstances on the pathogenesis and incidence of PPD. The search, selection and retrieval of the articles published during the last three years were systematically performed. The results from the primary studies indicate that unfavorable contemporary socio-geopolitical and environmental circumstances (e.g. Covid-19 pandemic, political conflicts/wars, and natural calamities; such as floods and earthquakes) detrimentally affect PPD etiology. A combination of socio-economic and psychological factors, including perceived lack of support and anxiousness about the future may contribute to drastic aggravation of PPD incidences. Finally, we outline some of the potential treatment regimens (e.g. inter-personal psycho- and art-based therapies) that may prove to be effective in amelioration of PPD-linked symptoms in birthing women, either alone or in complementation with traditional pharmacological interventions. We propose these psychological and art-based intervention strategies may beneficially counteract the negative influences of the unfortunate recent events across multiple cultures, societies and geographical regions.


Assuntos
Depressão Pós-Parto , Desastres Naturais , Feminino , Humanos , Depressão Pós-Parto/psicologia , Pandemias , Incidência , Período Pós-Parto/psicologia , Mães/psicologia , Fatores de Risco
9.
ACS Omega ; 8(49): 46309-46324, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38107881

RESUMO

Pectin is a structural polysaccharide present in plants that primarily consists of galacturonic acid units. This Review discusses the chemistry of pectin, including its composition and molecular weight. Pectin is conventionally extracted from agricultural waste (fruit and vegetable peels) using an acidic or basic aqueous medium at high temperatures. These processes are time- and energy-consuming and also result in severe environmental problems due to the production of acidic effluents and equipment corrosion. As pectin usage is increasing in food industries for developing different products and it is also used as an excipient in pharmaceutical products, better extraction procedures are required to maximize the yield and purity. The Review encompasses various alternate green approaches for the extraction of pectin, including traditional acid extraction and various emerging technologies such as deep eutectic solvent-based extraction, enzyme-assisted extraction, subcritical fluid extraction, ultrasound-assisted extraction, and microwave-based extraction, and evaluates the yield and physicochemical characteristics of the extracted pectin. This work aims to provide a platform for attracting more thorough research focused on the engineering of novel and more efficient green methods for the extraction of pectin and its utilization for various biotechnological purposes.

10.
bioRxiv ; 2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37961094

RESUMO

Since it was proposed as a potential host-directed antiviral agent for SARS-CoV-2, the antiparasitic drug ivermectin has been investigated thoroughly in clinical trials, which have provided insufficient support for its clinical efficacy. To examine the potential for ivermectin to be repurposed as an antiviral agent, we therefore undertook a series of preclinical studies. Consistent with early reports, ivermectin decreased SARS-CoV-2 viral burden in in vitro models at low micromolar concentrations, five- to ten-fold higher than the reported toxic clinical concentration. At similar concentrations, ivermectin also decreased cell viability and increased biomarkers of cytotoxicity and apoptosis. Further mechanistic and profiling studies revealed that ivermectin nonspecifically perturbs membrane bilayers at the same concentrations where it decreases the SARS-CoV-2 viral burden, resulting in nonspecific modulation of membrane-based targets such as G-protein coupled receptors and ion channels. These results suggest that a primary molecular mechanism for the in vitro antiviral activity of ivermectin may be nonspecific membrane perturbation, indicating that ivermectin is unlikely to be translatable into a safe and effective antiviral agent. These results and experimental workflow provide a useful paradigm for performing preclinical studies on (pandemic-related) drug repurposing candidates.

11.
Ageing Res Rev ; 91: 102056, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37673131

RESUMO

Agmatine, an endogenous polyamine derived from L-arginine, elicits tremendous multimodal neuromodulant properties. Alterations in agmatinergic signalling are closely linked to the pathogeneses of several brain disorders. Importantly, exogenous agmatine has been shown to act as a potent neuroprotectant in varied pathologies, including brain ageing and associated comorbidities. The antioxidant, anxiolytic, analgesic, antidepressant and memory-enhancing activities of agmatine may derive from its ability to regulate several cellular pathways; including cell metabolism, survival and differentiation, nitric oxide signalling, protein translation, oxidative homeostasis and neurotransmitter signalling. This review briefly discusses mammalian metabolism of agmatine and then proceeds to summarize our current understanding of neuromodulation and neuroprotection mediated by agmatine. Further, the emerging exciting bidirectional links between agmatine and the resident gut microbiome and their implications for brain pathophysiology and ageing are also discussed.


Assuntos
Agmatina , Microbioma Gastrointestinal , Fármacos Neuroprotetores , Animais , Agmatina/metabolismo , Agmatina/farmacologia , Encéfalo/metabolismo , Mamíferos/metabolismo , Neuroproteção , Fármacos Neuroprotetores/farmacologia
12.
IDCases ; 33: e01821, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37415782

RESUMO

We report a case of a 32-year-old male with a history of type 1 diabetes, inhaled drug use, and alcohol use disorder, who presented with encephalopathy, holocranial headaches, neck pain, confusion, and generalized tonic-clonic seizures. The patient initially presented at a rural community hospital with a fever and was found to be in diabetic ketoacidosis (DKA). He was also hemodynamically stable but stuporous, prompting intubation to protect his airway. Despite initial treatment measures, his neurological condition worsened and he remained ventilator-dependent. Key findings include a high glucose level, presence of ketones, and evidence of drug use. Blood cultures showed no growth, but his febrile state persisted. Cerebrospinal fluid (CSF) analysis revealed mild pleocytosis, hyperglycorrhachia but normal protein, with no growth. Neuroimaging showed right hemispheric slowing on EEG and diffusion restriction in the right frontal lobe on MRI. The patient's neurological status worsened on the second day of admission, manifesting as sluggish pupillary reflexes, right third nerve palsy, and decerebrate posturing. Emergent MRI suggested cerebral edema, leading to initiation of hypertonic saline. This case highlights the diagnostic challenges and critical management considerations in a patient with multiple comorbidities presenting with unexplained neurological deterioration, emphasizing the importance of a comprehensive and timely approach to diagnosis and treatment.

13.
Proc Natl Acad Sci U S A ; 120(25): e2218896120, 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37327313

RESUMO

Programmed ferroptotic death eliminates cells in all major organs and tissues with imbalanced redox metabolism due to overwhelming iron-catalyzed lipid peroxidation under insufficient control by thiols (Glutathione (GSH)). Ferroptosis has been associated with the pathogenesis of major chronic degenerative diseases and acute injuries of the brain, cardiovascular system, liver, kidneys, and other organs, and its manipulation offers a promising new strategy for anticancer therapy. This explains the high interest in designing new small-molecule-specific inhibitors against ferroptosis. Given the role of 15-lipoxygenase (15LOX) association with phosphatidylethanolamine (PE)-binding protein 1 (PEBP1) in initiating ferroptosis-specific peroxidation of polyunsaturated PE, we propose a strategy of discovering antiferroptotic agents as inhibitors of the 15LOX/PEBP1 catalytic complex rather than 15LOX alone. Here we designed, synthesized, and tested a customized library of 26 compounds using biochemical, molecular, and cell biology models along with redox lipidomic and computational analyses. We selected two lead compounds, FerroLOXIN-1 and 2, which effectively suppressed ferroptosis in vitro and in vivo without affecting the biosynthesis of pro-/anti-inflammatory lipid mediators in vivo. The effectiveness of these lead compounds is not due to radical scavenging or iron-chelation but results from their specific mechanisms of interaction with the 15LOX-2/PEBP1 complex, which either alters the binding pose of the substrate [eicosatetraenoyl-PE (ETE-PE)] in a nonproductive way or blocks the predominant oxygen channel thus preventing the catalysis of ETE-PE peroxidation. Our successful strategy may be adapted to the design of additional chemical libraries to reveal new ferroptosis-targeting therapeutic modalities.


Assuntos
Ferroptose , Proteína de Ligação a Fosfatidiletanolamina , Glutationa/metabolismo , Ferro/metabolismo , Peroxidação de Lipídeos , Lipídeos , Oxirredução , Proteína de Ligação a Fosfatidiletanolamina/antagonistas & inibidores
14.
RSC Med Chem ; 14(5): 921-933, 2023 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-37252106

RESUMO

As an adaptation for survival during infection, Mycobacterium tuberculosis becomes dormant, reducing its metabolism and growth. Two types of citrate synthases have been identified in Mycobacterium tuberculosis, GltA2 and CitA. Previous work shows that overexpression of CitA, the secondary citrate synthase, stimulates the growth of Mycobacterium tuberculosis under hypoxic conditions without showing accumulation of triacylglycerols and makes mycobacteria more sensitive to antibiotics, suggesting that CitA may play a role as a metabolic switch during infection and may be an interesting TB drug target. To assess the druggability and possible mechanisms of targeting CitA with small-molecule compounds, the CitA crystal structure was solved to 2.1 Å by X-ray crystallography. The solved structure shows that CitA lacks an NADH binding site that would afford allosteric regulation, which is atypical of most citrate synthases. However, a pyruvate molecule is observed within the analogous domain, suggesting pyruvate may instead be the allosteric regulator for CitA. The R149 and R153 residues forming the charged portion of the pyruvate binding pocket were mutated to glutamate and methionine, respectively, to assess the effect of mutations on activity. Protein thermal shift assay shows thermal stabilization of CitA in the presence of pyruvate compared to the two CitA variants designed to decrease pyruvate affinity. Solved crystal structures of both variants show no significant structural changes. However, the catalytic efficiency of the R153M variant increases by 2.6-fold. Additionally, we show that covalent modification of C143 of CitA by Ebselen completely arrests enzyme activity. Similar inhibition is observed using two spirocyclic Michael acceptor containing compounds, which inhibit CitA with ICapp50 values of 6.6 and 10.9 µM. A crystal structure of CitA modified by Ebselen was solved, but significant structural changes were lacking. Considering that covalent modification of C143 inactivates CitA and the proximity of C143 to the pyruvate binding site, this suggests that structural and/or chemical changes in this sub-domain are responsible for regulating CitA enzymatic activity.

15.
Phytother Res ; 37(5): 2119-2143, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37014255

RESUMO

Rosmarinic acid (RA) is a natural phenolic compound present in culinary herbs of the Boraginaceae, Lamiaceae/Labiatae, and Nepetoideae families. While the medicinal applications of these plants have been known for ages, RA has only been relatively recently established as an effective ameliorative agent against various disorders including cardiac diseases, cancer, and neuropathologies. In particular, several studies have confirmed the neuroprotective potential of RA in multiple cellular and animal models, as well as in clinical studies. The neuroprotective effects mediated by RA stem from its multimodal actions on a plethora of cellular and molecular pathways; including oxidative, bioenergetic, neuroinflammatory, and synaptic signaling. In recent years, RA has garnered tremendous interest as an ideal therapeutic candidate for treating neurodegenerative diseases. This review first briefly discusses the pharmacokinetics of RA and then proceeds to detail the neuroprotective mechanisms of RA at the molecular levels. Finally, the authors focus on the ameliorative potential of RA against several central nervous system (CNS) disorders, ranging from neuropsychological stress and epilepsy to neurodegenerative diseases such as Alzheimer's disease, Huntington's disease, Parkinson's disease, Lewy body dementia, and amyotrophic lateral sclerosis.


Assuntos
Doença de Alzheimer , Doenças Neurodegenerativas , Fármacos Neuroprotetores , Animais , Doenças Neurodegenerativas/tratamento farmacológico , Doença de Alzheimer/tratamento farmacológico , Neuroproteção , Cinamatos/farmacologia , Cinamatos/uso terapêutico , Cinamatos/metabolismo , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Ácido Rosmarínico
16.
Crit Care Nurs Q ; 46(1): 17-34, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36415065

RESUMO

Neurological emergencies carry significant morbidity and mortality, and it is necessary to have a multidisciplinary approach involving the emergency physician, the neurologist, the intensivist, and the critical care nursing staff. These disorders can be broadly divided into noninfectious and infectious etiologies. In this article, we review a few of the neurological emergencies that present to the neurological intensive unit, with emphasis on convulsive status epileptics, myasthenia gravis, Guillain-Barré syndrome, meningitis, encephalitis, and brain abscess.


Assuntos
Enfermagem de Cuidados Críticos , Emergências , Humanos , Unidades de Terapia Intensiva
17.
Proc Natl Acad Sci U S A ; 119(18): e2115071119, 2022 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-35476515

RESUMO

Activation of inhibitor of nuclear factor NF-κB kinase subunit-ß (IKKß), characterized by phosphorylation of activation loop serine residues 177 and 181, has been implicated in the early onset of cancer. On the other hand, tissue-specific IKKß knockout in Kras mutation-driven mouse models stalled the disease in the precancerous stage. In this study, we used cell line models, tumor growth studies, and patient samples to assess the role of IKKß and its activation in cancer. We also conducted a hit-to-lead optimization study that led to the identification of 39-100 as a selective mitogen-activated protein kinase kinase kinase (MAP3K) 1 inhibitor. We show that IKKß is not required for growth of Kras mutant pancreatic cancer (PC) cells but is critical for PC tumor growth in mice. We also observed elevated basal levels of activated IKKß in PC cell lines, PC patient-derived tumors, and liver metastases, implicating it in disease onset and progression. Optimization of an ATP noncompetitive IKKß inhibitor resulted in the identification of 39-100, an orally bioavailable inhibitor with improved potency and pharmacokinetic properties. The compound 39-100 did not inhibit IKKß but inhibited the IKKß kinase MAP3K1 with low-micromolar potency. MAP3K1-mediated IKKß phosphorylation was inhibited by 39-100, thus we termed it IKKß activation modulator (IKAM) 1. In PC models, IKAM-1 reduced activated IKKß levels, inhibited tumor growth, and reduced metastasis. Our findings suggests that MAP3K1-mediated IKKß activation contributes to KRAS mutation-associated PC growth and IKAM-1 is a viable pretherapeutic lead that targets this pathway.


Assuntos
MAP Quinase Quinase Quinase 1 , Neoplasias Pancreáticas , Humanos , Quinase I-kappa B/metabolismo , Neoplasias Pancreáticas/tratamento farmacológico , Proteínas Serina-Treonina Quinases , Neoplasias Pancreáticas
18.
Bioorg Med Chem Lett ; 65: 128713, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35367592

RESUMO

The IKK-NFκB complex is a key signaling node that facilitates activation of gene expression in response to extracellular signals. The kinase IKKß and the transcription factor RELA have been targeted by covalent modifiers that bind to surface exposed cysteine residues. A common feature in well characterized covalent modifiers of RELA and IKKß is the Michael acceptor containing α-methylene-γ-butyrolactone functionality. Through synthesis and evaluation of a focused set of α-methylene-γ-butyrolactone containing spirocyclic dimers (SpiDs) we identified SpiD3 as an anticancer agent with low nanomolar potency. Using cell-free and cell-based studies we show that SpiD3 is a covalent modifier that generates stable RELA containing high molecular weight complexes. SpiD3 inhibits TNFα-induced IκBα phosphorylation resulting in the blockade of RELA nuclear translocation. SpiD3 induces apoptosis, inhibits colony formation and migration of cancer cells. The NCI-60 cell line screen revealed that SpiD3 potently inhibits growth of leukemia cell lines, making it a suitable pre-therapeutic lead for hematological malignancies.


Assuntos
Antineoplásicos , Isatina , 4-Butirolactona/análogos & derivados , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Quinase I-kappa B/metabolismo , Isatina/farmacologia , NF-kappa B/metabolismo , Fosforilação , Proteínas Serina-Treonina Quinases , Fator de Transcrição RelA/genética , Fator de Transcrição RelA/metabolismo
19.
J Biol Chem ; 298(5): 101890, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35378132

RESUMO

The unfolded protein response (UPR) is an adaptation mechanism activated to resolve transient accumulation of unfolded/misfolded proteins in the endoplasmic reticulum. Failure to resolve the transient accumulation of such proteins results in UPR-mediated programmed cell death. Loss of tumor suppressor gene or oncogene addiction in cancer cells can result in sustained higher basal UPR levels; however, it is not clear if these higher basal UPR levels in cancer cells can be exploited as a therapeutic strategy. We hypothesized that covalent modification of surface-exposed cysteine (SEC) residues could simulate unfolded/misfolded proteins to activate the UPR, and that higher basal UPR levels in cancer cells would provide the necessary therapeutic window. To test this hypothesis, here we synthesized analogs that can covalently modify multiple SEC residues and evaluated them as UPR activators. We identified a spirocyclic dimer, SpiD7, and evaluated its effects on UPR activation signals, that is, XBP1 splicing, phosphorylation of eIF2α, and a decrease in ATF 6 levels, in normal and cancer cells, which were further confirmed by RNA-Seq analyses. We found that SpiD7 selectively induced caspase-mediated apoptosis in cancer cells, whereas normal cells exhibited robust XBP1 splicing, indicating adaptation to stress. Furthermore, SpiD7 inhibited the growth of high-grade serous carcinoma cell lines ~3-15-fold more potently than immortalized fallopian tube epithelial (paired normal control) cells and reduced clonogenic growth of high-grade serous carcinoma cell lines. Our results suggest that induction of the UPR by covalent modification of SEC residues represents a cancer cell vulnerability and can be exploited to discover novel therapeutics.


Assuntos
Apoptose , Carcinoma , Resposta a Proteínas não Dobradas , Carcinoma/tratamento farmacológico , Carcinoma/metabolismo , Linhagem Celular Tumoral , Descoberta de Drogas , Retículo Endoplasmático/metabolismo , Estresse do Retículo Endoplasmático , Fator de Iniciação 2 em Eucariotos/metabolismo , Humanos
20.
RSC Chem Biol ; 3(1): 32-36, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-35128406

RESUMO

Tumor necrosis factor (TNF) α-induced nuclear translocation of the NF-κB subunit RELA has been implicated in several pathological conditions. Here we report the discovery of a spirocyclic dimer (SpiD7) that covalently modifies RELA to inhibit TNFα-induced nuclear translocation. This is a previously unexplored strategy to inhibit TNFα-induced NF-κB activation.

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