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1.
J Enzyme Inhib Med Chem ; 31(6): 1520-6, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27146339

RESUMEN

New isatin-triazole based hybrids have been synthesized and evaluated for their inhibitory activity of TNF-α induced expression of Intercellular Adhesion Molecule-1 (ICAM-1) on the surface of human endothelial cells. Structure-activity relationship (SAR) studies revealed that the presence of the electron-attracting bromo substituent at position-5 of the isatin moiety played an important role in enhancing the anti-inflammatory potential of the synthesized compounds. Z-1-[3-(1H-1,2,4-Triazol-1-yl)propyl]-5-bromo-3-[2-(4-methoxyphenyl)hydrazono]indolin-2-one (19) with an IC50 = 20 µM and 89% ICAM-1 inhibition with MTD at 200 µM was found to be the most potent of all the synthesized derivatives. Introduction of 1,2,4-triazole ring and electron-donating methoxy group on the phenylhydrazone moiety resulted in four-fold increase of the anti-inflammatory activity.


Asunto(s)
Antiinflamatorios/síntesis química , Antiinflamatorios/farmacología , Isatina/farmacología , Triazoles/química , Antiinflamatorios/química , Espectroscopía de Resonancia Magnética con Carbono-13 , Células Cultivadas , Endotelio Vascular/citología , Endotelio Vascular/efectos de los fármacos , Ensayo de Inmunoadsorción Enzimática , Humanos , Espectroscopía de Protones por Resonancia Magnética , Espectrofotometría Infrarroja , Relación Estructura-Actividad
2.
Molecules ; 21(11)2016 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-27834873

RESUMEN

Highly regioselective acylation has been observed in 7,8-dihydroxy-4-methylcoumarin (DHMC) by the lipase from Rhizopus oryzae suspended in tetrahydrofuran (THF) at 45 °C using six different acid anhydrides as acylating agents. The acylation occurred regioselectively at one of the two hydroxy groups of the coumarin moiety resulting in the formation of 8-acyloxy-7-hydroxy-4-methylcoumarins, which are important bioactive molecules for studying biotansformations in animals, and are otherwise very difficult to obtain by only chemical steps. Six monoacylated, monohydroxy 4-methylcoumarins have been biocatalytically synthesised and identified on the basis of their spectral data and X-ray crystal analysis.


Asunto(s)
Cumarinas/química , Cumarinas/síntesis química , Proteínas Fúngicas/química , Lipasa/química , Rhizopus/enzimología , Cristalografía por Rayos X , Ésteres/síntesis química , Ésteres/química , Estructura Molecular
3.
Pharm Biol ; 54(1): 105-10, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26017566

RESUMEN

CONTEXT: Cancer is a leading cause of death worldwide and novel chemotherapeutic agents with better efficacy and safety profiles are much needed. Coumarins are natural polyphenolic compounds with important pharmacological activities, which are present in many dietary plants and herbal remedies. OBJECTIVES: The objective of this study is to investigate natural and synthetic coumarin derivatives with considerable anticancer capacity against three human cancer cell lines. MATERIALS AND METHODS: We synthesized 27 coumarin derivatives (mostly having 4-methyl moiety) and examined their cytotoxic effect on three human cancer cell lines, K562 (chronic myelogenous leukemia), LS180 (colon adenocarcinoma), and MCF-7 (breast adenocarcinoma) by MTT reduction assay. Screened compounds included 7-hydroxy-4-methylcoumarins (7-HMCs), 7-acetoxy-4-methylcoumarins (7-AMCs), and different dihydroxy-4-methylcoumarin (DHMC) and diacetoxy-4-methylcoumarin (DAMC) derivatives. Some compounds with methoxy, amine, and bromine substitutions were also examined. RESULTS: 7,8-DHMCs bearing alkyl groups at C3 position were the most effective subgroup, and of which, the most potent is compound 11, with an n-decyl chain at C3, which had IC50 values of 42.4, 25.2, and 25.1 µM against K562, LS180, and MCF-7 cells, respectively. The second most active subgroup was 7,8-DAMCs containing ethoxycarbonylmethyl and ethoxycarbonylethyl moieties at C3 position. Compound 27 (6-bromo-4-bromomethyl-7-hydroxycoumarin), the only derivative containing bromine also showed reasonable cytotoxic activities (IC50 range: 32.7-45.8 µM). DISCUSSION AND CONCLUSION: This structure-activity relationship (SAR) study of 4-methylcoumarins shows that further investigation of these derivatives may lead to the discovery of novel anticancer agents.


Asunto(s)
Antineoplásicos/farmacología , Cumarinas/farmacología , Neoplasias/tratamiento farmacológico , Antineoplásicos/síntesis química , Supervivencia Celular/efectos de los fármacos , Cumarinas/síntesis química , Relación Dosis-Respuesta a Droga , Humanos , Concentración 50 Inhibidora , Células K562 , Células MCF-7 , Metilación , Estructura Molecular , Neoplasias/patología , Relación Estructura-Actividad
4.
Bioorg Chem ; 53: 83-91, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24632507

RESUMEN

It has been demonstrated that Lipozyme® TL IM (Thermomyces lanuginosus lipase immobilised on silica) can selectively deacylate the ester function involving the C-5' hydroxyl group of α-anomers over the other acyl functions of anomeric mixture of peracylated O-aryl α,ß-D-ribofuranoside. The analysis of results of biocatalytic deacylation reaction revealed that the reaction time decreases with the increase in the acyl chain length from C1 to C4. The unique selectivity of Lipozyme® TL IM has been harnessed for the separation of anomeric mixture of peracylated O-aryl α,ß-D-ribofuranosides, The lipase mediated selective deacylation methodology has been used for the synthesis of O-aryl α-D-ribofuranosides and O-aryl ß-D-ribofuranosides in pure forms, which can be used as chromogenic substrate for the detection of pathogenic microbial parasites containing glycosidases.


Asunto(s)
Glicósidos/metabolismo , Lipasa/metabolismo , Resinas Acrílicas/química , Acilación , Biocatálisis , Enzimas Inmovilizadas/química , Enzimas Inmovilizadas/metabolismo , Eurotiales/enzimología , Glicósidos/química
5.
RSC Adv ; 14(13): 8932-8962, 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38500612

RESUMEN

Numerous studies in the field of alkaloid chemistry have provided researchers with valuable insights into their unique properties as catalysts. Among the diverse natural catalysts, caffeine has emerged as a green, expedient, and biodegradable catalyst with high efficiency and applicability. Interest in using caffeine as a catalyst has burgeoned over the past few years with its role in diverse multicomponent reactions. Preparation of its imidazolium salts and further conversion to Nitrogen Heterocyclic Carbene (NHC) ligands and ionic liquids offers new paradigms. Caffeine has also played a multifaceted role as a support material in influencing the structural properties of nanoparticles. We hope that the chemistry of caffeine and its applications for sustainable organic transformations discussed in this review will stimulate new thinking and open new avenues in this field.

6.
Carbohydr Res ; 536: 109018, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38185030

RESUMEN

A proficient approach has been developed for the synthesis of substituted 2H-chromenes from C1-substituted glucal. The key step of our synthetic methodology was C-H activation in propylene carbonate solvent followed by 6π-electrocyclization aromatization in ethylene glycol as greener substitutes to toxic aprotic solvents, to obtain 2H-chromenes in a stepwise manner. The application of the developed methodology was further explored with the synthesis of a small library of substituted 2H-chromenes in good yields.


Asunto(s)
Benzopiranos , Paladio , Ciclización , Catálisis
7.
Top Curr Chem (Cham) ; 382(1): 4, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38296918

RESUMEN

Pyrimidine is a pharmacologically important moiety that exhibits diverse biological activities. This review reflects the growing significance of transition metal-catalyzed reactions for the synthesis of pyrimidines (with no discussion being made on the transition metal-catalyzed functionalization of pyrimidines). The effect of different catalysts on the selectivity/yields of pyrimidines and catalyst recyclability (wherever applicable) are described, together with attempts to illustrate the role of the catalyst through mechanisms. Although several methods have been researched for synthesizing this privileged scaffold, there has been a considerable push to expand transition metal-catalyzed, sustainable, efficient and selective synthetic strategies leading to pyrimidines. The aim of the authors with this update (2017-2023) is to drive the designing of new transition metal-mediated protocols for pyrimidine synthesis.


Asunto(s)
Elementos de Transición , Pirimidinas , Catálisis
8.
RSC Adv ; 14(24): 17102-17139, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38808245

RESUMEN

Chromones are well known as fundamental structural elements found in numerous natural compounds and medicinal substances. The Schiff bases of chromones have a much wider range of pharmacological applications such as antitumor, antioxidant, anti-HIV, antifungal, anti-inflammatory, and antimicrobial properties. A lot of research has been carried out on chromone-based copper(ii) Schiff-base complexes owing to their role in the organometallic domain and promise as potential bioactive cores. This review article is centered on copper(ii) Schiff-base complexes derived from chromones, highlighting their diverse range of pharmacological applications documented in the past decade, as well as the future research opportunities they offer.

9.
Cureus ; 16(5): e59738, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38841032

RESUMEN

Background Post-acute care (PAC) centers are facilities used for recuperation, rehabilitation, and symptom management in an effort to improve the long-term outcomes of patients. PAC centers include skilled nursing facilities, inpatient rehabilitation facilities, and long-term care hospitals. In the 1990s, Medicare payment reforms significantly increased the discharge rates to PAC centers and subsequently increased the length of stay (LOS) among these patient populations. Over the last several years, there have been national initiatives and multidisciplinary approaches to improve safe discharge rates to home. Multiple studies have shown that patients who are discharged to home have decreased rates of 30-day readmissions, reduced short-term mortality, and an improvement in their activities of daily living.  Objectives This study aimed to investigate how multidisciplinary approaches could improve a single institution's discharge rates to home. In doing so, we aim to lower hospital readmission rates, hospital length of stay, morbidity and mortality rates, and healthcare-associated costs. Methods A retrospective single-institution cohort study was implemented at Jersey Shore University Medical Center (JSUMC). Data from January 2015 to December 2019 served as the control period, compared to the intervention period from January 2020 to January 2024. Patients were either admitted to JSUMC teaching faculty, hospitalists, or "others," which is composed of various medical and surgical subspecialists. Interventions performed to improve home discharge rates can be categorized into the following: physician education, patient education, electronic medical record (EMR) initiatives, accountability, and daily mobility initiatives. All interventions were performed equally across the three patient populations. The primary endpoint was the proportion of patients discharged to home. Results There were 190,699 patients, divided into a pre-intervention group comprising 98,885 individuals and a post-intervention group comprising 91,814 patients. Within the pre-intervention group, the faculty attended to 8,495 patients, hospitalists cared for 39,145 patients, and others managed 51,245 patients. In the post-intervention period, the faculty oversaw 8,014 patients, hospitalists attended to 35,094 patients, and others were responsible for 48,706 patients. After implementing a series of multidisciplinary interventions, there was a significant increase in the proportion of patients discharged home, rising from 74.9% to 80.2% across the entire patient population. Specifically, patients under the care of the faculty experienced a more substantial improvement, with a discharge rate increasing from 73.6% to 84.4%. Similarly, the hospitalists exhibited a rise from 69.4% to 74.3%, and the others demonstrated an increase from 79.3% to 83.7%. All observed changes yielded a p-value < 0.001. Conclusions By deploying a multifaceted strategy that emphasized physician education, patient education, EMR initiatives, accountability measures, and daily mobility, there was a statistically significant increase in the rate of patient discharges to home. These initiatives proved to be cost-effective and led to a tangible reduction in healthcare-associated costs and patient length of stay. Further studies are required to look into the effect on hospital readmission rates and morbidity and mortality rates. The comprehensive approach showcased its potential to optimize patient outcomes.

10.
Cureus ; 15(11): e48298, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38058341

RESUMEN

Background Early ambulation during acute hospitalization has been associated with improved clinical outcomes for patients. Despite the benefits of mobility in the hospital setting, physical therapists and nursing staff are often constrained by time. Mobility technicians (MTs) are individuals with specialized training who have emerged as a potential solution by providing safe ambulation for patients during their hospital stay. Objectives The purpose of this quality improvement project was to investigate the impact of MTs on clinical and financial outcomes for admitted patients at a high-volume tertiary institution. Methods A quality improvement project was implemented at Jersey Shore University Medical Center, Neptune City, from October 2022 to March 2023. The study was a prospective, single-institution cohort study and included patients admitted to two medical floors. Patients were divided into an experimental group that received services from MTs and a control group that did not receive this service but was eligible based on clinical status. The primary endpoint was the proportion of patients discharged to home. Secondary outcomes included the length of stay and financial impact. Results A total of 396 admitted patients were included, with 222 patients in the MT group and 174 in the non-MT group. Patients in the MT group were discharged home more frequently, at a rate of 79.7% compared to 66.1% for patients in the non-MT group (p = 0.002). MTs contributed to an average 2.4-day reduction in the length of hospital stay (7.8 days vs. 10.2 days, p = 0.007). The MT intervention led to an estimated net savings of $148,500 during the six-month study period. Additionally, 2.9 daily hospital beds were created. Conclusion Implementing an MT program significantly increased the discharge-to-home rates and decreased hospital length of stay. Preliminary analysis suggests that this intervention is cost-effective and can assist institutions in managing increased hospital capacity strain through the creation of additional hospital beds.

11.
Protein Expr Purif ; 85(1): 117-24, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22809717

RESUMEN

Phosphoglucomutase (PGM) plays an important role in polysaccharide capsule formation and virulence in a number of bacterial pathogens. However, the enzyme has not yet been characterized from Mycobacterium tuberculosis (Mtb). Here, we report the biochemical properties of recombinant Mtb-PGM as well as the in silico structural analysis from Mtb H37Rv. The purified recombinant enzyme was enzymatically active with a specific activity of 67.5 U/mg and experimental k(cat) of 70.31 s(-1) for the substrate glucose-1-phosphate. The enzyme was stable in pH range 6.5-7.4 and exhibited temperature optima range between 30 and 40°C. Various kinetic parameters and constants of the rPGM were determined. A structural comparison of Modeller generated 3D Mtb-PGM structure with rabbit muscle PGM revealed that the two enzymes share the same overall heart shape and four-domain architecture, despite having only 17% sequence identity. However, certain interesting differences between the two have been identified, which provide an opportunity for designing new drugs to specifically target the Mtb-PGM. Also, in the absence of the crystal structure of the Mtb-PGM, the modeled structure could be further explored for in silico docking studies with suitable inhibitors.


Asunto(s)
Mycobacterium tuberculosis/enzimología , Fosfoglucomutasa/genética , Fosfoglucomutasa/metabolismo , Secuencia de Aminoácidos , Animales , Clonación Molecular , Modelos Moleculares , Datos de Secuencia Molecular , Mycobacterium tuberculosis/química , Mycobacterium tuberculosis/genética , Fosfoglucomutasa/química , Filogenia , Replegamiento Proteico , Conejos , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Análisis de Secuencia , Homología Estructural de Proteína
12.
Proc Natl Acad Sci U S A ; 106(22): 8912-7, 2009 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-19447925

RESUMEN

Ectopic expression of defined transcription factors can reprogram somatic cells to induced pluripotent stem (iPS) cells, but the utility of iPS cells is hampered by the use of viral delivery systems. Small molecules offer an alternative to replace virally transduced transcription factors with chemical signaling cues responsible for reprogramming. In this report we describe a small-molecule screening platform applied to identify compounds that functionally replace the reprogramming factor Klf4. A series of small-molecule scaffolds were identified that activate Nanog expression in mouse fibroblasts transduced with a subset of reprogramming factors lacking Klf4. Application of one such molecule, kenpaullone, in lieu of Klf4 gave rise to iPS cells that are indistinguishable from murine embryonic stem cells. This experimental platform can be used to screen large chemical libraries in search of novel compounds to replace the reprogramming factors that induce pluripotency. Ultimately, such compounds may provide mechanistic insight into the reprogramming process.


Asunto(s)
Benzazepinas/farmacología , Diferenciación Celular , Epigénesis Genética/efectos de los fármacos , Fibroblastos/efectos de los fármacos , Indoles/farmacología , Células Madre Pluripotentes/citología , Bibliotecas de Moléculas Pequeñas/farmacología , Animales , Fibroblastos/citología , Genes Reporteros , Proteínas de Homeodominio/genética , Factor 4 Similar a Kruppel , Factores de Transcripción de Tipo Kruppel/genética , Luciferasas/genética , Ratones , Proteína Homeótica Nanog
13.
Mol Cancer Ther ; 21(9): 1462-1472, 2022 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-35793468

RESUMEN

Extra domain B splice variant of fibronectin (EDB+FN) is an extracellular matrix protein (ECM) deposited by tumor-associated fibroblasts, and is associated with tumor growth, angiogenesis, and invasion. We hypothesized that EDB+FN is a safe and abundant target for therapeutic intervention with an antibody-drug conjugate (ADC). We describe the generation, pharmacology, mechanism of action, and safety profile of an ADC specific for EDB+FN (EDB-ADC). EDB+FN is broadly expressed in the stroma of pancreatic, non-small cell lung (NSCLC), breast, ovarian, head and neck cancers, whereas restricted in normal tissues. In patient-derived xenograft (PDX), cell-line xenograft (CLX), and mouse syngeneic tumor models, EDB-ADC, conjugated to auristatin Aur0101 through site-specific technology, demonstrated potent antitumor growth inhibition. Increased phospho-histone H3, a pharmacodynamic biomarker of response, was observed in tumor cells distal to the target site of tumor ECM after EDB-ADC treatment. EDB-ADC potentiated infiltration of immune cells, including CD3+ T lymphocytes into the tumor, providing rationale for the combination of EDB-ADC with immune checkpoint therapy. EDB-ADC and anti-PD-L1 combination in a syngeneic breast tumor model led to enhanced antitumor activity with sustained tumor regressions. In nonclinical safety studies in nonhuman primates, EDB-ADC had a well-tolerated safety profile without signs of either on-target toxicity or the off-target effects typically observed with ADCs that are conjugated through conventional conjugation methods. These data highlight the potential for EDB-ADC to specifically target the tumor microenvironment, provide robust therapeutic benefits against multiple tumor types, and enhance activity antitumor in combination with checkpoint blockade.


Asunto(s)
Neoplasias de la Mama , Inmunoconjugados , Animales , Neoplasias de la Mama/patología , Línea Celular Tumoral , Femenino , Fibronectinas/metabolismo , Humanos , Inmunoconjugados/farmacología , Inmunoconjugados/uso terapéutico , Ratones , Neovascularización Patológica/metabolismo , Microambiente Tumoral , Ensayos Antitumor por Modelo de Xenoinjerto
14.
Biomacromolecules ; 12(10): 3487-98, 2011 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-21834595

RESUMEN

Sugar-PEG-based polymers were synthesized by enzymatic copolymerization of 4-C-hydroxymethyl-1,2-O-isopropylidene-ß-L-threo-pentofuranose/4-C-hydroxymethyl-1,2-O-benzylidene-ß-L-threo-pentofuranose/4-C-hydroxymethyl-1,2-O-isopropylidene-3-O-pentyl-ß-L-threo-pentofuranose with PEG-600 dimethyl ester using Novozyme-435 (Candida antarctica lipase immobilized on polyacrylate). Carbohydrate monomers were obtained by the multistep synthesis starting from diacetone-D-glucose and PEG-600 dimethyl ester, which was in turn obtained by the esterification of the commercially available PEG-600 diacid. Aggregation studies on the copolymers revealed that in aqueous solution those polymers bearing the hydrophobic pentyl/benzylidene moiety spontaneously self-assembled into supramolecular aggregates. The critical aggregation concentration (CAC) of polymers was determined by surface tension measurements, and the precise size of the aggregates was obtained by dynamic light scattering. The polymeric aggregates were further explored for their drug encapsulation properties in buffered aqueous solution of pH 7.4 (37 °C) using nile red as a hydrophobic model compound by means of UV/vis and fluorescence spectroscopy. There was no significant encapsulation in polymer synthesized from 4-C-hydroxymethyl-1,2-O-isopropylidene-ß-L-threo-pentofuranose because this sugar monomer does not contain a big hydrophobic moiety as the pentyl or the benzylidene moiety. Nile red release study was performed at pH 5.0 and 7.4 using fluorescence spectroscopy. The release of nile red from the polymer bearing benzylidene moiety and pentyl moiety was observed with a half life of 3.4 and 2.0 h, respectively at pH 5.0, whereas no release was found at pH 7.4.


Asunto(s)
Biocatálisis , Materiales Biocompatibles/química , Portadores de Fármacos/química , Lipasa/metabolismo , Polisacáridos/metabolismo , Materiales Biocompatibles/metabolismo , Portadores de Fármacos/metabolismo , Composición de Medicamentos , Enzimas Inmovilizadas , Proteínas Fúngicas , Glucosa/análogos & derivados , Glucosa/química , Glucosa/metabolismo , Concentración de Iones de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Luz , Espectroscopía de Resonancia Magnética , Micelas , Oxazinas/análisis , Oxazinas/metabolismo , Tamaño de la Partícula , Polietilenglicoles/química , Polietilenglicoles/metabolismo , Polimerizacion , Polisacáridos/química , Dispersión de Radiación , Espectrometría de Fluorescencia
15.
Nucleosides Nucleotides Nucleic Acids ; 40(12): 1220-1236, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34636267

RESUMEN

Nucleosides play a pivotal role in biological systems and therefore have attracted a lot of interest as chemotherapeutic agents in drug discovery. Over the years biocatalysts have emerged as a sustainable alternative to conventional synthetic catalysts. As a nature's catalyst, they exhibit excellent selectivity, remarkable tolerance, and help in carrying out eco-friendly benign processes. The use of a biocatalyst as a regio- and enantioselective catalyst is particularly relevant in the transformations of nucleosides and their analogs because of the presence of multiple chiral centres. Herein, we discuss the recent advances in the Pseudomonas Cepacia Lipase mediated selective acylation and deacylation reactions of the secondary hydroxyl and amino groups of nucleosides and their analogs.


Asunto(s)
Lipasa/metabolismo , Nucleósidos/metabolismo , Acilación , Biocatálisis , Burkholderia cepacia/enzimología , Estructura Molecular , Estereoisomerismo
16.
Mol Imaging Biol ; 23(6): 941-951, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34143379

RESUMEN

PURPOSE: A sensitive and specific imaging biomarker to monitor immune activation and quantify pharmacodynamic responses would be useful for development of immunomodulating anti-cancer agents. PF-07062119 is a T cell engaging bispecific antibody that binds to CD3 and guanylyl cyclase C, a protein that is over-expressed by colorectal cancers. Here, we used 89Zr-Df-IAB22M2C (89Zr-Df-Crefmirlimab), a human CD8-specific minibody to monitor CD8+ T cell infiltration into tumors by positron emission tomography. We investigated the ability of 89Zr-Df-IAB22M2C to track anti-tumor activity induced by PF-07062119 in a human CRC adoptive transfer mouse model (with injected activated/expanded human T cells), as well as the correlation of tumor radiotracer uptake with CD8+ immunohistochemical staining. PROCEDURES: NOD SCID gamma mice bearing human CRC LS1034 tumors were treated with four different doses of PF-07062119, or a non-targeted CD3 BsAb control, and imaged with 89Zr-Df-IAB22M2C PET at days 4 and 9. Following PET/CT imaging, mice were euthanized and dissected for ex vivo distribution analysis of 89Zr-Df-IAB22M2C in tissues on days 4 and 9, with additional data collected on day 6 (supplementary). Data were analyzed and reported as standard uptake value and %ID/g for in vivo imaging and ex vivo tissue distribution. In addition, tumor tissues were evaluated by immunohistochemistry for CD8+ T cells. RESULTS: The results demonstrated substantial mean uptake of 89Zr-Df-IAB22M2C (%ID/g) in PF-07062119-treated tumors, with significant increases in comparison to non-targeted BsAb-treated controls, as well as PF-07062119 dose-dependent responses over time of treatment. A moderate correlation was observed between tumor tissue radioactivity uptake and CD8+ cell density, demonstrating the value of the imaging agent for non-invasive assessment of intra-tumoral CD8+ T cells and the mechanism of action for PF-07062119. CONCLUSION: Immune-imaging technologies for quantitative cellular measures would be a valuable biomarker in immunotherapeutic clinical development. We demonstrated a qualification of 89Zr-IAB22M2C PET to evaluate PD responses (mice) to a novel immunotherapeutic.


Asunto(s)
Tomografía Computarizada por Tomografía de Emisión de Positrones , Circonio , Animales , Biomarcadores , Línea Celular Tumoral , Ratones , Ratones SCID , Tomografía de Emisión de Positrones/métodos , Receptores de Enterotoxina , Linfocitos T
17.
MAbs ; 13(1): 1850395, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33459147

RESUMEN

We report here the discovery and optimization of a novel T cell retargeting anti-GUCY2C x anti-CD3ε bispecific antibody for the treatment of solid tumors. Using a combination of hybridoma, phage display and rational design protein engineering, we have developed a fully humanized and manufacturable CD3 bispecific antibody that demonstrates favorable pharmacokinetic properties and potent in vivo efficacy. Anti-GUCY2C and anti-CD3ε antibodies derived from mouse hybridomas were first humanized into well-behaved human variable region frameworks with full retention of binding and T-cell mediated cytotoxic activity. To address potential manufacturability concerns, multiple approaches were taken in parallel to optimize and de-risk the two antibody variable regions. These approaches included structure-guided rational mutagenesis and phage display-based optimization, focusing on improving stability, reducing polyreactivity and self-association potential, removing chemical liabilities and proteolytic cleavage sites, and de-risking immunogenicity. Employing rapid library construction methods as well as automated phage display and high-throughput protein production workflows enabled efficient generation of an optimized bispecific antibody with desirable manufacturability properties, high stability, and low nonspecific binding. Proteolytic cleavage and deamidation in complementarity-determining regions were also successfully addressed. Collectively, these improvements translated to a molecule with potent single-agent in vivo efficacy in a tumor cell line adoptive transfer model and a cynomolgus monkey pharmacokinetic profile (half-life>4.5 days) suitable for clinical development. Clinical evaluation of PF-07062119 is ongoing.


Asunto(s)
Anticuerpos Biespecíficos/inmunología , Complejo CD3/inmunología , Inmunoterapia Adoptiva/métodos , Neoplasias/terapia , Receptores de Enterotoxina/inmunología , Animales , Anticuerpos Biespecíficos/farmacocinética , Anticuerpos Biespecíficos/uso terapéutico , Línea Celular Tumoral , Femenino , Humanos , Hibridomas , Macaca fascicularis/inmunología , Macaca fascicularis/metabolismo , Ratones Endogámicos BALB C , Neoplasias/inmunología , Neoplasias/metabolismo , Ingeniería de Proteínas/métodos , Anticuerpos de Cadena Única/inmunología , Anticuerpos de Cadena Única/farmacocinética , Anticuerpos de Cadena Única/uso terapéutico , Linfocitos T/inmunología , Linfocitos T/metabolismo
18.
Curr Opin Genet Dev ; 16(5): 455-62, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16920351

RESUMEN

Transcriptional regulators and epigenetic modifiers play crucial roles throughout development to ensure that proper gene expression patterns are established and maintained in any given cell type. Recent genome-wide studies have begun to unravel how genetic and epigenetic factors maintain the undifferentiated state of embryonic stem cells while allowing these cells to remain poised to differentiate into somatic cells in response to developmental cues. These studies provide a conceptual framework for understanding pluripotency and lineage-specification at the molecular level.


Asunto(s)
Diferenciación Celular , Células Madre Pluripotentes/citología , Células Madre Pluripotentes/metabolismo , Animales , Linaje de la Célula , Epigénesis Genética , Regulación del Desarrollo de la Expresión Génica , Humanos , Factores de Transcripción/metabolismo
19.
Artículo en Inglés | MEDLINE | ID: mdl-20445242

RESUMEN

Phosphoglucose isomerase (PGI) plays a key role in both glycolysis and gluconeogenesis inside the cell, whereas outside the cell it exhibits cytokine properties. PGI is also known to act as an autocrine motility factor, a neuroleukin agent and a differentiation and maturation mediator. Here, the first crystal structure of PGI from Mycobacterium tuberculosis H37Rv (Mtb) is reported. The structure was refined at 2.25 A resolution and revealed the presence of one molecule in the asymmetric unit with two globular domains. As known previously, the active site of Mtb PGI contains conserved residues including Glu356, Glu216 and His387 (where His387 is from the neighbouring molecule). The crystal structure of Mtb PGI was observed to be rather more similar to human PGI than other nonbacterial PGIs, with only a few differences being detected in the loops, arm and hook regions of the human and Mtb PGIs, suggesting that the M. tuberculosis enzyme uses the same enzyme mechanism.


Asunto(s)
Glucosa-6-Fosfato Isomerasa/química , Mycobacterium tuberculosis/enzimología , Secuencia de Aminoácidos , Dicroismo Circular , Cristalografía por Rayos X , Glucosa-6-Fosfato Isomerasa/genética , Modelos Moleculares , Datos de Secuencia Molecular , Mutación , Estructura Terciaria de Proteína
20.
Clin Cancer Res ; 26(9): 2188-2202, 2020 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-31996389

RESUMEN

PURPOSE: Gastrointestinal cancers remain areas of high unmet need despite advances in targeted and immunotherapies. Here, we demonstrate potent, tumor-selective efficacy with PF-07062119, a T-cell engaging CD3 bispecific targeting tumors expressing Guanylyl Cyclase C (GUCY2C), which is expressed widely across colorectal cancer and other gastrointestinal malignancies. In addition, to address immune evasion mechanisms, we explore combinations with immune checkpoint blockade agents and with antiangiogenesis therapy. EXPERIMENTAL DESIGN: PF-07062119 activity was evaluated in vitro in multiple tumor cell lines, and in vivo in established subcutaneous and orthotopic human colorectal cancer xenograft tumors with adoptive transfer of human T cells. Efficacy was also evaluated in mouse syngeneic tumors using human CD3ε transgenic mice. IHC and mass cytometry were performed to demonstrate drug biodistribution, recruitment of activated T cells, and to identify markers of immune evasion. Combination studies were performed with anti-PD-1/PD-L1 and anti-VEGF antibodies. Toxicity and pharmacokinetic studies were done in cynomolgus macaque. RESULTS: We demonstrate that GUCY2C-positive tumors can be targeted with an anti-GUCY2C/anti-CD3ε bispecific, with selective drug biodistribution to tumors. PF-07062119 showed potent T-cell-mediated in vitro activity and in vivo efficacy in multiple colorectal cancer human xenograft tumor models, including KRAS- and BRAF-mutant tumors, as well as in the immunocompetent mouse syngeneic tumor model. PF-07062119 activity was further enhanced when combined with anti-PD-1/PD-L1 treatment or in combination with antiangiogenic therapy. Toxicity studies in cynomolgus indicated a monitorable and manageable toxicity profile. CONCLUSIONS: These data highlight the potential for PF-07062119 to demonstrate efficacy and improve patient outcomes in colorectal cancer and other gastrointestinal malignancies.


Asunto(s)
Anticuerpos Biespecíficos/administración & dosificación , Complejo CD3/inmunología , Neoplasias Colorrectales/terapia , Neoplasias Gastrointestinales/terapia , Inmunoterapia/métodos , Receptores de Enterotoxina/inmunología , Linfocitos T/inmunología , Traslado Adoptivo/métodos , Animales , Anticuerpos Biespecíficos/farmacocinética , Línea Celular Tumoral , Neoplasias Colorrectales/inmunología , Neoplasias Colorrectales/metabolismo , Modelos Animales de Enfermedad , Femenino , Neoplasias Gastrointestinales/inmunología , Neoplasias Gastrointestinales/metabolismo , Humanos , Ratones , Ratones Endogámicos NOD , Ratones SCID , Distribución Tisular
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