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1.
Biomolecules ; 14(8)2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39199355

RESUMEN

p53 is a crucial tumor suppressor in vertebrates that is frequently mutated in human cancers. Most mutations are missense mutations that render p53 inactive in suppressing tumor initiation and progression. Developing small-molecule drugs to convert mutant p53 into an active, wild-type-like conformation is a significant focus for personalized cancer therapy. Prior research indicates that reactivating p53 suppresses cancer cell proliferation and tumor growth in animal models. Early clinical evidence with a compound selectively targeting p53 mutants with substitutions of tyrosine 220 suggests potential therapeutic benefits of reactivating p53 in patients. This study identifies and examines the UCI-1001 compound series as a potential corrector for several p53 mutations. The findings indicate that UCI-1001 treatment in p53 mutant cancer cell lines inhibits growth and reinstates wild-type p53 activities, including DNA binding, target gene activation, and induction of cell death. Cellular thermal shift assays, conformation-specific immunofluorescence staining, and differential scanning fluorometry suggest that UCI-1001 interacts with and alters the conformation of mutant p53 in cancer cells. These initial results identify pyrimidine trione derivatives of the UCI-1001 series as candidates for p53 corrector drug development.


Asunto(s)
Pirimidinas , Proteína p53 Supresora de Tumor , Humanos , Proteína p53 Supresora de Tumor/metabolismo , Proteína p53 Supresora de Tumor/genética , Pirimidinas/farmacología , Pirimidinas/química , Proliferación Celular/efectos de los fármacos , Línea Celular Tumoral , Mutación , Antineoplásicos/farmacología , Antineoplásicos/química , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patología
2.
Bioorg Chem ; 150: 107526, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38878749

RESUMEN

In this review, the current progress in the research and development of butyrylcholinesterase (BChE) reactivators is summarised and the advantages or disadvantages of these reactivators are critically discussed. Organophosphorus compounds such as nerve agents (sarin, tabun, VX) or pesticides (chlorpyrifos, diazinon) cause irreversible inhibition of acetylcholinesterase (AChE) and BChE in the human body. While AChE inhibition can be life threatening due to cholinergic overstimulation and crisis, selective BChE inhibition has presumably no adverse effects. Because BChE is mostly found in plasma, its activity is important for the scavenging of organophosphates before they can reach AChE in the central nervous system. Therefore, this enzyme in combination with its reactivator can be used as a pseudo-catalytic scavenger of organophosphates. Three structural types of BChE reactivators were found, i.e. bisquaternary salts, monoquaternary salts and uncharged compounds. Although the reviewed reactivators have certain limitations, the promising candidates for BChE reactivation were found in each structural group.


Asunto(s)
Butirilcolinesterasa , Inhibidores de la Colinesterasa , Compuestos Organofosforados , Butirilcolinesterasa/metabolismo , Butirilcolinesterasa/química , Compuestos Organofosforados/química , Compuestos Organofosforados/farmacología , Humanos , Inhibidores de la Colinesterasa/química , Inhibidores de la Colinesterasa/farmacología , Inhibidores de la Colinesterasa/síntesis química , Estructura Molecular , Reactivadores de la Colinesterasa/farmacología , Reactivadores de la Colinesterasa/química , Reactivadores de la Colinesterasa/síntesis química , Relación Estructura-Actividad , Animales , Acetilcolinesterasa/metabolismo , Acetilcolinesterasa/química
3.
Int J Mol Sci ; 25(11)2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38891812

RESUMEN

Organophosphoate (OP) chemicals are known to inhibit the enzyme acetylcholinesterase (AChE). Studying OP poisoning is difficult because common small animal research models have serum carboxylesterase, which contributes to animals' resistance to OP poisoning. Historically, guinea pigs have been used for this research; however, a novel genetically modified mouse strain (KIKO) was developed with nonfunctional serum carboxylase (Es1 KO) and an altered acetylcholinesterase (AChE) gene, which expresses the amino acid sequence of the human form of the same protein (AChE KI). KIKO mice were injected with 1xLD50 of an OP nerve agent or vehicle control with or without atropine. After one to three minutes, animals were injected with 35 mg/kg of the currently fielded Reactivator countermeasure for OP poisoning. Postmortem brains were imaged on a Bruker RapifleX ToF/ToF instrument. Data confirmed the presence of increased acetylcholine in OP-exposed animals, regardless of treatment or atropine status. More interestingly, we detected a small amount of Reactivator within the brain of both exposed and unexposed animals; it is currently debated if reactivators can cross the blood-brain barrier. Further, we were able to simultaneously image acetylcholine, the primary affected neurotransmitter, as well as determine the location of both Reactivator and acetylcholine in the brain. This study, which utilized sensitive MALDI-MSI methods, characterized KIKO mice as a functional model for OP countermeasure development.


Asunto(s)
Acetilcolinesterasa , Modelos Animales de Enfermedad , Intoxicación por Organofosfatos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Animales , Ratones , Humanos , Acetilcolinesterasa/metabolismo , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Atropina/farmacología , Encéfalo/metabolismo , Encéfalo/patología , Encéfalo/efectos de los fármacos , Ratones Noqueados , Inhibidores de la Colinesterasa , Acetilcolina/metabolismo
4.
Toxicol Lett ; 397: 103-116, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38703967

RESUMEN

Animal research continues to serve a critical role in the testing and development of medical countermeasures. The Göttingen minipig, developed for laboratory research, may provide many benefits for addressing research questions within chemical defense. Targeted development of the Göttingen minipig model could reduce reliance upon non-human primates, and improve study design, statistical power, and throughput to advance medical countermeasures for regulatory approval and fielding. In this vein, we completed foundational pharmacokinetics and physiological safety studies of intramuscularly administered atropine sulfate, pralidoxime chloride (2-PAM), and diazepam across a broad range of doses (1-6 autoinjector equivalent) using adult male Göttingen minipigs (n=11; n=4-8/study) surgically implanted with vascular access ports and telemetric devices to monitor cardiovascular, respiratory, arterial pressure, and temperature signals. Pharmacokinetic data were orderly and the concentration maximum mirrored available human data at comparably scaled doses clearly for atropine, moderately for 2-PAM, and poorly for diazepam. Time to peak concentration approximated 2, 7, and 20 min for atropine, 2-PAM, and diazepam, respectively, and the elimination half-life of these drugs approximated 2 hr (atropine), 3 hr (2-PAM), and 8 hr (diazepam). Atropine sulfate dose-dependently increased the magnitude and duration of tachycardia and decreased the PR and ST intervals (consistent with findings obtained from other species). Mild hypothermia was observed at the highest diazepam dose. Göttingen minipigs appear to provide a ready and appropriate large animal alternative to non-human primates, and further development and evaluation of novel nerve agent medical countermeasures and treatment strategies in this model are justified.


Asunto(s)
Atropina , Diazepam , Porcinos Enanos , Animales , Porcinos , Masculino , Diazepam/farmacocinética , Diazepam/farmacología , Atropina/farmacocinética , Atropina/farmacología , Agentes Nerviosos/farmacocinética , Agentes Nerviosos/toxicidad , Relación Dosis-Respuesta a Droga , Inyecciones Intramusculares , Semivida , Frecuencia Cardíaca/efectos de los fármacos , Telemetría , Modelos Animales , Compuestos de Pralidoxima
5.
Chem Biol Interact ; 395: 110973, 2024 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-38574837

RESUMEN

The first organophosphorus nerve agent was discovered accidently during the development of pesticides, shortly after the first use of chemical weapons (chlorine, phosgene) on the battlefield during World War I. Despite the Chemical Weapons Convention banning these substances, they have still been employed in wars, terrorist attacks or political assassinations. Characterised by their high lethality, they target the nervous system by inhibiting the acetylcholinesterase (AChE) enzyme, preventing neurotransmission, which, if not treated rapidly, inevitably leads to serious injury or the death of the person intoxicated. The limited efficacy of current antidotes, known as AChE reactivators, pushes research towards new treatments. Numerous paths have been explored, from modifying the original pyridinium oximes to developing hybrid reactivators seeking a better affinity for the inhibited AChE. Another crucial approach resides in molecules more prone to cross the blood-brain barrier: uncharged compounds, bio-conjugated reactivators or innovative formulations. Our aim is to raise awareness on the threat and toxicity of organophosphorus nerve agents and to present the main synthetic efforts deployed since the first AChE reactivator, to tackle the task of efficiently treating victims of these chemical warfare agents.


Asunto(s)
Agentes Nerviosos , Compuestos Organofosforados , Humanos , Agentes Nerviosos/toxicidad , Compuestos Organofosforados/toxicidad , Animales , Reactivadores de la Colinesterasa/farmacología , Reactivadores de la Colinesterasa/uso terapéutico , Reactivadores de la Colinesterasa/química , Contramedidas Médicas , Acetilcolinesterasa/metabolismo , Inhibidores de la Colinesterasa/toxicidad , Sustancias para la Guerra Química/toxicidad , Antídotos/farmacología , Antídotos/uso terapéutico , Oximas/farmacología , Oximas/uso terapéutico , Oximas/química
6.
Chem Biol Interact ; 394: 110941, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38493910

RESUMEN

The current study imposes a new class of organophosphorus (OP)-inhibited cholinesterase reactivators by conceptualizing a family of asymmetric bisoximes with various reactivating scaffolds. Several novel nucleophilic warheads were investigated, putting forward 29 novel reactivating options, by evaluating their nucleophilicity and ability to directly decompose OP compounds. Adopting the so-called zwitterionic strategy, 17 mono-oxime and nine bisoxime reactivators were discovered with major emphasis on the bifunctional-moiety approach. Compounds were compared with clinically used standards and other known experimentally highlighted reactivators. Our results clearly favor the concept of asymmetric bisoximes as leading reactivators in terms of efficacy and versatility. These top-ranked compounds were characterized in detail by reactivation kinetics parameters and evaluated for potential CNS availability. The highlighted molecules 55, 57, and 58 with various reactivating warheads, surpassed the reactivating potency of pralidoxime and several notable uncharged reactivators. The versatility of lead drug candidate 55 was also inspected on OP-inhibited butyrylcholinesterase, revealing a much higher rate compared to existing clinical antidotes.


Asunto(s)
Butirilcolinesterasa , Reactivadores de la Colinesterasa , Intoxicación por Organofosfatos , Oximas , Oximas/química , Oximas/farmacología , Reactivadores de la Colinesterasa/química , Reactivadores de la Colinesterasa/farmacología , Butirilcolinesterasa/metabolismo , Butirilcolinesterasa/química , Humanos , Intoxicación por Organofosfatos/tratamiento farmacológico , Acetilcolinesterasa/metabolismo , Antídotos/química , Antídotos/farmacología , Cinética , Inhibidores de la Colinesterasa/química , Inhibidores de la Colinesterasa/farmacología , Animales , Compuestos Organofosforados/química
7.
Chin J Nat Med ; 22(2): 112-126, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38342564

RESUMEN

The tumor suppressor protein p53 is central to cancer biology, with its pathway reactivation emerging as a promising therapeutic strategy in oncology. This study introduced LZ22, a novel compound that selectively inhibits the growth, migration, and metastasis of tumor cells expressing wild-type p53, demonstrating ineffectiveness in cells devoid of p53 or those expressing mutant p53. LZ22's mechanism of action involves a high-affinity interaction with the histidine-96 pocket of the MDM2 protein. This interaction disrupted the MDM2-p53 binding, consequently stabilizing p53 by shielding it from proteasomal degradation. LZ22 impeded cell cycle progression and diminished cell proliferation by reinstating the p53-dependent suppression of the CDK2/Rb signaling pathway. Moreover, LZ22 alleviated the p53-dependent repression of Snail transcription factor expression and its consequent EMT, effectively reducing tumor cell migration and distal metastasis. Importantly, LZ22 administration in tumor-bearing mice did not manifest notable side effects. The findings position LZ22 as a structurally unique reactivator of p53, offering therapeutic promise for the management of human cancers with wild-type TP53.


Asunto(s)
Factores de Transcripción , Proteína p53 Supresora de Tumor , Ratones , Humanos , Animales , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Línea Celular Tumoral , Proliferación Celular , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Transducción de Señal , Quinasa 2 Dependiente de la Ciclina/metabolismo
8.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-1039122

RESUMEN

The p53 protein is an essential tumor suppressor in the human body that plays a critical role in preventing tumor formation by controlling cell cycle arrest and promoting apoptosis. Mutations in the p53 gene are frequently observed in more than 50% of tumor tissues and lead to the generation of mutant p53 proteins, which not only have a dominant-negative effect (DN) that hinders the function of wild-type p53 protein but also have gain-of-function (GOF) effects that stimulate tumor development by regulating cell metabolism, invasion, migration, and other processes. Therefore, mutant p53 protein has become a specific drug target for cancer therapy. However, the lack of a drug-binding pocket and smooth surface of mutant p53 proteins have made them undruggable targets for a long time. In recent years, with the development of high-throughput screening technology and an enhanced understanding of the structure and conformational changes exhibited by mutant p53 proteins, a multitude of small molecule compounds directed against mutant p53 protein have been identified, exhibiting substantial in vitro anti-tumor efficacy. Moreover, some of these compounds have entered clinical trials. This review summarized the direct and indirect strategies for the treatment of cancers targeting mutant p53, with a primary focus on the mechanisms of action of small molecule compounds that reactivate mutant p53 protein or degrade mutant p53 protein. The aim is to provide assistance for the development of innovative drugs targeting mutant p53 protein in the future.

9.
Chem Biol Interact ; 385: 110734, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37788753

RESUMEN

Acetylcholinesterase (AChE, EC 3.1.1.7) reactivators (2-PAM, trimedoxime, obidoxime, asoxime) have become an integral part of antidotal treatment in cases of nerve agent and organophosphorus (OP) pesticide poisonings. They are often referred to as specific antidotes due to their ability to restore AChE function when it has been covalently inhibited by an OP compound. Currently available commercial reactivators exhibit limited ability to penetrate the blood-brain barrier, where reactivation of inhibited AChE is crucial. Consequently, there have been numerous efforts to discover more brain-penetrating AChE reactivators. In this study, we examined a derivative of 2-PAM designed to possess increased lipophilicity. This enhanced lipophilicity was achieved through the incorporation of a benzyl group into its molecular structure. Initially, a molecular modeling study was conducted, followed by a comparison of its reactivation efficacy with that of 2-PAM against 10 different AChE inhibitors in vitro. Unfortunately, this relatively significant structural modification of 2-PAM resulted in a decrease in its reactivation potency. Consequently, this derivative cannot be considered as a broad-spectrum AChE reactivator.


Asunto(s)
Reactivadores de la Colinesterasa , Intoxicación por Organofosfatos , Humanos , Reactivadores de la Colinesterasa/química , Acetilcolinesterasa/metabolismo , Compuestos de Pralidoxima/farmacología , Antídotos/farmacología , Oximas/farmacología , Oximas/química , Inhibidores de la Colinesterasa/farmacología , Inhibidores de la Colinesterasa/metabolismo
10.
Bioorg Med Chem Lett ; 96: 129504, 2023 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-37838342

RESUMEN

This study aimed to explore non-pyridinium oxime acetylcholinesterase (AChE) reactivators that could hold the potential to overcome the limitations of the currently available compounds used in the clinic to treat the neurologic manifestations induced by intoxication with organophosphorus agents. Fifteen compounds with various non-pyridinium oxime moieties were evaluated for AChE activity at different concentrations, including aldoximes, ketoximes, and α-ketoaldoximes. The therapeutic potential of the oxime compounds was evaluated by assessing their ability to reactivate AChE inhibited by paraoxon. Among the tested compounds, α-Ketoaldoxime derivative 13 showed the highest reactivation (%) reaching 67 % and 60 % AChE reactivation when evaluated against OP-inhibited electric eel AChE at concentrations of 1,000 and 100 µM, respectively. Compound 13 showed a comparable reactivation ability of AChE (60 %) compared to that of pralidoxime (56 %) at concentrations of 100 µM. Molecular docking simulation of the most active compounds 12 and 13 was conducted to predict the binding mode of the reactivation of electric eel AChE. As a result, a non-pyridinium oxime moiety 13, is a potential reactivator of OP-inhibited AChE and is taken as a lead compound for the development of novel AChE reactivators with enhanced capacity to freely cross the blood-brain barrier.


Asunto(s)
Reactivadores de la Colinesterasa , Oximas , Oximas/farmacología , Oximas/química , Paraoxon/farmacología , Acetilcolinesterasa/metabolismo , Reactivadores de la Colinesterasa/farmacología , Reactivadores de la Colinesterasa/química , Inhibidores de la Colinesterasa/farmacología , Inhibidores de la Colinesterasa/química , Simulación del Acoplamiento Molecular , Compuestos de Piridinio/farmacología , Compuestos de Piridinio/química , Acetamidas , Compuestos Organofosforados/química
11.
Bioorg Chem ; 141: 106858, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37774432

RESUMEN

A series of new uncharged conjugates of adenine, 3,6-dimetyl-, 1,6-dimethyl- and 6-methyluracil with 1,2,4-triazole-3-hydroxamic and 1,2,3-triazole-4-hydroxamic acid moieties were synthesized and studied as reactivators of organophosphate-inhibited cholinesterase. It is shown that triazole-hydroxamic acids can reactivate acetylcholinesterase (AChE) inhibited by paraoxon (POX) in vitro, offering reactivation constants comparable to those of pralidoxime (2-PAM). However, in contrast to 2-PAM, triazole-hydroxamic acids demonstrated the ability to reactivate AChE in the brain of rats poisoned with POX. At a dose of 200 mg/kg (i.v.), the lead compound 3e reactivated 22.6 ± 7.3% of brain AChE in rats poisoned with POX. In a rat model of POX-induced delayed neurodegeneration, compound 3e reduced the neuronal injury labeled with FJB upon double administration 1 and 3 h after poisoning. Compound 3e was also shown to prevent memory impairment of POX-poisoned rats as tested in a Morris water maze.


Asunto(s)
Reactivadores de la Colinesterasa , Intoxicación por Organofosfatos , Ratas , Animales , Acetilcolinesterasa , Reactivadores de la Colinesterasa/farmacología , Inhibidores de la Colinesterasa/farmacología , Intoxicación por Organofosfatos/tratamiento farmacológico , Ácidos Hidroxámicos , Paraoxon/farmacología , Oximas/farmacología
12.
Arch Toxicol ; 97(11): 2839-2860, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37642747

RESUMEN

Oxime reactivators of acetylcholinesterase are commonly used to treat highly toxic organophosphate poisoning. They are effective nucleophiles that can restore the catalytic activity of acetylcholinesterase; however, their main limitation is the difficulty in crossing the blood-brain barrier (BBB) because of their strongly hydrophilic nature. Various approaches to overcome this limitation and enhance the bioavailability of oxime reactivators in the CNS have been evaluated; these include structural modifications, conjugation with molecules that have transporters in the BBB, bypassing the BBB through intranasal delivery, and inhibition of BBB efflux transporters. A promising approach is the use of nanoparticles (NPs) as the delivery systems. Studies using mesoporous silica nanomaterials, poly (L-lysine)-graft-poly(ethylene oxide) NPs, metallic organic frameworks, poly(lactic-co-glycolic acid) NPs, human serum albumin NPs, liposomes, solid lipid NPs, and cucurbiturils, have shown promising results. Some NPs are considered as nanoreactors for organophosphate detoxification; these combine bioscavengers with encapsulated oximes. This study provides an overview and critical discussion of the strategies used to enhance the bioavailability of oxime reactivators in the central nervous system.


Asunto(s)
Acetilcolinesterasa , Sistema Nervioso Central , Humanos , Disponibilidad Biológica , Barrera Hematoencefálica , Transporte Biológico
13.
Invest New Drugs ; 41(4): 587-595, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37402008

RESUMEN

Pancreatic cancer (PC) is one of the deadliest malignancies; p53 is mutated in approximately 75% of PC patients. Hence, the protein derived from mutant/wild-type TP53 may represent a therapeutic target. Interestingly, a p53 reactivator (PRIMA-1MET) showed promise in clinical trials of haematological malignancies; therefore, it warrants an in vitro evaluation in PC cell lines. To evaluate the antiproliferative effects of PRIMA-1MET, either alone or combined with the common chemotherapy 5-fluorouracil (5-FU), against mutated and wild-type p53 PC cell lines. This study involved p53-mutant (AsPC-1) and p53-wild type (Capan-2) PC cell lines. The cytotoxicity of PRIMA-1MET alone or in combination with 5-FU was evaluated by MTT assay. Synergism was assessed by calculating the combination index (CI) via CalcuSyn software. Fluorescence microscopy was used to analyse apoptosis following acridine orange/ethidium bromide (AO/EB) staining. Morphological changes were investigated with an inverted microscope. Quantitative reverse transcription PCR (RT‒qPCR) was used to measure gene expression. Both PC cell lines were sensitive to PRIMA-1MET monotherapy. Furthermore, PRIMA-1MET and 5-FU had a synergistic effect (CI < 1), reflected by significant enhancement of apoptosis and morphological changes in the combination vs. monotherapy treatments. Moreover, the RT‒qPCR results indicated increased expression of the NOXA and TP73 genes in combination-treated cells. Our data suggested that PRIMA-1MET, whether alone or combined with 5-FU, has an antiproliferative effect on PC cell lines regardless of p53 mutational status. The synergism of the combination was associated with significant apoptosis induction through p53-dependent and p53-independent pathways. Preclinical confirmation of these data in in vivo models is highly recommended.


Asunto(s)
Neoplasias Pancreáticas , Proteína p53 Supresora de Tumor , Humanos , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Fluorouracilo/farmacología , Línea Celular Tumoral , Apoptosis , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas
14.
Structure ; 30(11): 1538-1549.e3, 2022 11 03.
Artículo en Inglés | MEDLINE | ID: mdl-36265484

RESUMEN

Organophosphorus (OP) compounds, including nerve agents and some pesticides, covalently bind to the catalytic serine of human acetylcholinesterase (hAChE), thereby inhibiting acetylcholine hydrolysis necessary for efficient neurotransmission. Oxime antidotes can reactivate the OP-conjugated hAChE, but reactivation efficiency can be low for pesticides, such as paraoxon (POX). Understanding structural and dynamic determinants of OP inhibition and reactivation can provide insights to design improved reactivators. Here, X-ray structures of hAChE with unaged POX, with POX and oximes MMB4 and RS170B, and with MMB4 are reported. A significant conformational distortion of the acyl loop was observed upon POX binding, being partially restored to the native conformation by oximes. Neutron vibrational spectroscopy combined with molecular dynamics simulations showed that picosecond vibrational dynamics of the acyl loop soften in the ∼20-50 cm-1 frequency range. The acyl loop structural perturbations may be correlated with its picosecond vibrational dynamics to yield more comprehensive template for structure-based reactivator design.


Asunto(s)
Acetilcolinesterasa , Plaguicidas , Humanos , Acetilcolinesterasa/química , Paraoxon/química , Cristalografía por Rayos X , Inhibidores de la Colinesterasa/química , Oximas/química , Compuestos Organofosforados , Neutrones
15.
Pharmacol Ther ; 236: 108234, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35732246

RESUMEN

The retinoblastoma gene (RB) was discovered as the first tumor-suppressor gene. It was subsequently shown to be inactivated in most malignant tumors, particularly at the protein level. Therefore, many activated oncogenes as well as inactivated tumor-suppressor genes inactivate the function of the RB protein. I hypothesized that most of the molecular-targeting agents against activated oncogenes may reactivate the function of RB, and proposed screening systems for agents up-regulating the expression of cyclin-dependent kinase inhibitors, such as p15, p27, and p21, which convert the phosphorylated inactive form of the RB protein to the unphosphorylated active form. I termed this screening as "RB-reactivator screening". Using the screening systems for agents that up-regulate the expression of p15, p27, and p21, we discovered the novel MEK inhibitor trametinib, the novel RAF/MEK inhibitor CH5126766/RO5126766/VS-6766, and the histone deacetylase inhibitor YM753/OBP-801, respectively. Trametinib exerted remarkable effects in patients with advanced BRAF mutant melanoma, and was approved in the USA as the first-in-class MEK inhibitor (trade name: Mekinist) in 2013. The British Pharmacological Society selected trametinib as the Drug Discovery of the Year in 2013. The combination of trametinib and the BRAF inhibitor dabrafenib was approved for advanced BRAF mutant melanoma in the USA, EU, Japan, and many other countries. Additionally, the US Food and Drug Administration (FDA) granted Breakthrough Therapy Designation for the combination of trametinib and dabrafenib in the treatment of patients with advanced BRAF mutant non-small cell lung cancer in 2015, and this combination was subsequently approved in the EU, USA, and Japan. In 2018, this combination was also approved for locally advanced or metastatic BRAF V600-mutant anaplastic thyroid cancer in the USA after it had been granted Breakthrough Therapy Designation by the FDA. I describe here the characterization of our original screening system, RB-reactivator screening, by which these three molecular-targeting agents that advanced into clinical trials were identified.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Descubrimiento de Drogas , Neoplasias Pulmonares , Melanoma , Piridonas , Pirimidinonas , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Descubrimiento de Drogas/métodos , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Melanoma/tratamiento farmacológico , Melanoma/genética , Quinasas de Proteína Quinasa Activadas por Mitógenos/antagonistas & inhibidores , Terapia Molecular Dirigida/métodos , Mutación , Oximas/farmacología , Oximas/uso terapéutico , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Proteínas Proto-Oncogénicas B-raf , Piridonas/farmacología , Piridonas/uso terapéutico , Pirimidinonas/farmacología , Pirimidinonas/uso terapéutico , Proteína de Retinoblastoma/genética , Proteína de Retinoblastoma/uso terapéutico
16.
Pharmaceuticals (Basel) ; 14(9)2021 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-34577642

RESUMEN

Elevated expression of placenta-specific protein 1 (PLAC1) is associated with the increased proliferation and invasiveness of a variety of human cancers, including ovarian cancer. Recent studies have shown that the tumor suppressor p53 directly suppresses PLAC1 transcription. However, mutations in p53 lead to the loss of PLAC1 transcriptional suppression. Small molecules that structurally convert mutant p53 proteins to wild-type conformations are emerging. Our objective was to determine whether the restoration of the wild-type function of mutated p53 could rescue PLAC1 transcriptional suppression in tumors harboring certain TP53 mutations. Ovarian cancer cells OVCAR3 and ES-2, both harboring TP53 missense mutations, were treated with the p53 reactivator HO-3867. Treatment with HO-3867 successfully rescued PLAC1 transcriptional suppression. In addition, cell proliferation was inhibited and cell death through apoptosis was increased in both cell lines. We conclude that the use of HO-3867 as an adjuvant to conventional therapeutics in ovarian cancers harboring TP53 missense mutations could improve patient outcomes. Validation of this conclusion must, however, come from an appropriately designed clinical trial.

17.
Chem Biol Interact ; 346: 109577, 2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-34274336

RESUMEN

The introduction of enzyme nanoreactors in medicine is relatively new. However, this technology has already been experimentally successful in cancer treatments, struggle against toxicity of reactive oxygen species in inflammatory processes, detoxification of drugs and xenobiotics, and correction of metabolic and genetic defects by using encapsulated enzymes, acting in single or cascade reactions. Biomolecules, e.g. enzymes, antibodies, reactive proteins capable of inactivating toxicants in the body are called bioscavengers. In this review, we focus on enzyme-containing nanoreactors for in vivo detoxification of organophosphorous compounds (OP) to be used for prophylaxis and post-exposure treatment of OP poisoning. A particular attention is devoted to bioscavenger-containing injectable nanoreactors operating in the bloodstream. The nanoreactor concept implements single or multiple enzymes and cofactors co-encapsulated in polymeric semi-permeable nanocontainers. Thus, the detoxification processes take place in a confined space containing highly concentrated bioscavengers. The article deals with historical and theoretical backgrounds about enzymatic detoxification of OPs in nanoreactors, nanoreactor polymeric enveloppes, realizations and advantages over other approaches using bioscavengers.


Asunto(s)
Nanoestructuras/química , Compuestos Organofosforados/metabolismo , Xenobióticos/metabolismo , Biocatálisis , Coenzimas/química , Coenzimas/metabolismo , Enzimas Inmovilizadas/química , Enzimas Inmovilizadas/metabolismo , Inactivación Metabólica , Nanotecnología , Compuestos Organofosforados/química , Polímeros/química
18.
Mol Pharm ; 18(6): 2416-2427, 2021 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-34019427

RESUMEN

Oxime-based molecules are used for the treatment of patients to reactivate acetylcholinesterase (AChE) function after organophosphate intoxication. However, their efficacy is limited by low penetration through the blood-brain barrier and fast elimination. In this work, the cucurbit[7]uril (CB[7]) carrier was used for the encapsulation of the clinical agent asoxime to enhance brain bioavailability and the treatment window. We present a pharmacokinetic study of asoxime and the asoxime-CB[7] complex in an in vivo mouse model. Ultrahigh-performance liquid chromatography with electrospray ionization-mass spectrometry detection was developed to determine asoxime and CB[7] in biological fluids and tissues after thorough optimization of chromatographic conditions. The dihydroxypropane-silica stationary phase using hydrophilic interaction liquid chromatography conditions provided the best chromatographic performance. The final method was validated and applied for the pharmacokinetic study of mouse plasma, urine, bile, liver, kidney, and brain samples at different times after administration of asoxime and the asoxime-CB[7] complex. The results showed a greater than 3-fold increase in the area under the curve (AUC) in the brain for asoxime administered as a complex with CB[7] relative to that for the administration of asoxime alone. The effectiveness of the treatment strategy was evaluated using a reactivation study and a functional observatory battery. Protection of brain AChE activity is crucial for saving human lives or reducing the consequences of poisoning. The asoxime administered as a complex increased the brain activity by approximately 30% compared to that with atropine alone. CB[7] coadministration improved the AChE activity by 11%, which agrees with the higher asoxime AUC assessed in the pharmacokinetic study.


Asunto(s)
Hidrocarburos Aromáticos con Puentes/química , Reactivadores de la Colinesterasa/administración & dosificación , Portadores de Fármacos/química , Imidazoles/química , Intoxicación por Organofosfatos/tratamiento farmacológico , Oximas/farmacocinética , Compuestos de Piridinio/farmacocinética , Acetilcolinesterasa/metabolismo , Animales , Área Bajo la Curva , Barrera Hematoencefálica/metabolismo , Inhibidores de la Colinesterasa/administración & dosificación , Inhibidores de la Colinesterasa/toxicidad , Reactivadores de la Colinesterasa/farmacocinética , Cromatografía Líquida de Alta Presión , Modelos Animales de Enfermedad , Pruebas de Enzimas , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Espectrometría de Masas , Ratones , Oximas/administración & dosificación , Compuestos de Piridinio/administración & dosificación , Sarín/administración & dosificación , Sarín/toxicidad
19.
J Pharm Sci ; 110(4): 1842-1852, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33545185

RESUMEN

Oxime reactivators of acetylcholinesterase (AChE) represent an integral part of standard antidote treatment of organophosphate poisoning. Oxime K869 is a novel bisquaternary non-symmetric pyridinium aldoxime with two pyridinium rings connected by a tetramethylene bridge where two chlorines modify the pyridinium ring bearing the oxime moiety. Based on in vitro assays, K869 is a potent AChE and butyrylcholinesterase (BChE) reactivator. For the investigation of the basic pharmacokinetic properties of K869 after its intramuscular application, new HPLC-UV and LC-MS/MS methods were developed and validated for its determination in rat body fluids and tissues. In this study, the SPE procedure for sample pretreatment was optimized as an alternative to routine protein precipitation widely used in oxime pharmacokinetics studies. K869 oxime is quickly absorbed into the central compartment reaching its maximum in plasma (39 ± 4 µg/mL) between 15 and 20 min. The majority of K869 was eliminated by kidneys via urine when compared with biliary excretion. However, only a limited amount of K869 (65 ± 4 ng/g of brain tissue) was found in the brain 30 min after oxime administration. Regarding the brain/plasma ratio calculated (less than 1%), the penetration of K869 into the brain did not exceed conventionally used oximes.


Asunto(s)
Líquidos Corporales , Reactivadores de la Colinesterasa , Acetilcolinesterasa , Animales , Inhibidores de la Colinesterasa , Cromatografía Liquida , Oximas , Ratas , Espectrometría de Masas en Tándem
20.
Arch Toxicol ; 95(3): 985-1001, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33517499

RESUMEN

To date, the only treatments developed for poisoning by organophosphorus compounds, the most toxic chemical weapons of mass destruction, have exhibited limited efficacy and versatility. The available causal antidotes are based on reactivation of the enzyme acetylcholinesterase (AChE), which is rapidly and pseudo-irreversibly inhibited by these agents. In this study, we developed a novel series of monoquaternary reactivators combining permanently charged moieties tethered to position 6- of 3-hydroxypyridine-2-aldoxime reactivating subunit. Highlighted representatives (21, 24, and 27; also coded as K1371, K1374, and K1375, respectively) that contained 1-phenylisoquinolinium, 7-amino-1-phenylisoquinolinium and 4-carbamoylpyridinium moieties as peripheral anionic site ligands, respectively, showed efficacy superior or comparable to that of the clinically used standards. More importantly, these reactivators exhibited wide-spectrum efficacy and were minutely investigated via determination of their reactivation kinetics in parallel with molecular dynamics simulations to study their mechanisms of reactivation of the tabun-inhibited AChE conjugate. To further confirm the potential applicability of these candidates, a mouse in vivo assay was conducted. While K1375 had the lowest acute toxicity and the most suitable pharmacokinetic profile, the oxime K1374 with delayed elimination half-life was the most effective in ameliorating the signs of tabun toxicity. Moreover, both in vitro and in vivo, the versatility of the agents was substantially superior to that of clinically used standards. Their high efficacy and broad-spectrum capability make K1374 and K1375 promising candidates that should be further investigated for their potential as nerve agents and insecticide antidotes.


Asunto(s)
Acetilcolinesterasa/efectos de los fármacos , Antídotos/farmacología , Reactivadores de la Colinesterasa/farmacología , Acetilcolinesterasa/metabolismo , Animales , Antídotos/síntesis química , Antídotos/química , Reactivadores de la Colinesterasa/síntesis química , Reactivadores de la Colinesterasa/química , Femenino , Masculino , Ratones , Ratones Endogámicos BALB C , Simulación de Dinámica Molecular , Oximas/síntesis química , Oximas/química , Oximas/farmacología , Relación Estructura-Actividad
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