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2.
Clin Cancer Res ; 28(18): 4092-4104, 2022 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-35180772

RESUMO

PURPOSE: Determine whether specific CTNNB1 or APC mutations in patients with desmoid tumor were associated with differences in clinical responses to systemic treatments. EXPERIMENTAL DESIGN: We established a multi-institutional dataset of previously treated patients with desmoid tumor across four U.S. sarcoma centers, including demographic and clinicopathologic characteristics, treatment regimens, and clinical and radiographic responses. CTNNB1 or APC mutation status was determined from prior pathology records, or archival tissue was requested and analyzed by Sanger sequencing and/or next-generation sequencing. Evaluable patients with mutation results were analyzed to determine clinical progression-free survival (cPFS), RECIST 1.1 PFS (rPFS), time to next treatment (TTNT), and overall survival (OS). Kaplan-Meier analysis and Cox proportional hazards regression were performed to identify differences in cPFS, rPFS, TTNT, and OS by mutation subtype, desmoid tumor location, and treatment regimen. RESULTS: A total of 259 evaluable patients were analyzed for at least one of the survival outcomes, with 177 patients having mutation data. First- and second-line cPFS, rPFS, and TTNT were not significantly affected by mutation subtype; however, APC-mutant desmoid tumors demonstrated nonstatistically significant inferior outcomes. Extremity/trunk desmoid tumor location and treatment with doxorubicin-based, methotrexate/vinca alkaloids and sorafenib regimens were associated with better clinical outcomes compared with surgery or "other" therapies, including estrogen-receptor blockade and imatinib. OS was significantly worse with APC or CTNNB1 negative/other mutations. CONCLUSIONS: Mutation subtype did not affect responses to specific systemic therapies. APC mutations and nonextremity desmoid tumor locations remain prognostic for worse outcomes, and earlier initiation of systemic therapy for these higher-risk desmoid tumors should be prospectively evaluated. See related commentary by Greene and Van Tine, p. 3911.


Assuntos
Fibromatose Agressiva , Fibromatose Agressiva/tratamento farmacológico , Fibromatose Agressiva/genética , Fibromatose Agressiva/patologia , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Mutação , Prognóstico , Estudos Retrospectivos , beta Catenina/genética
4.
J Immunother Cancer ; 7(1): 296, 2019 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-31703609

RESUMO

BACKGROUND: Adoptive transfer of autologous T-lymphocytes transduced with a high affinity NY-ESO-1-reactive T-cell receptor (NY-ESO-1c259 T-cells) has emerged as a promising therapeutic strategy for patients with refractory synovial sarcoma. Secondary autoimmune T-cell mediated toxicities can occur long after initial adoptive T-cell transfer. We report on the first two cases of the development and management of Guillain-Barre syndrome in synovial sarcoma patients who received NY-ESO-1c259 T-cells. CASE PRESENTATION: A 47 year-old woman and 39 year-old woman with refractory metastatic SS were treated with fludarabine-cyclophosphamide lymphodepletion followed by adoptive transfer of NY-ESO-1c259 T-cells. On day 42 after adoptive T-cell therapy, patient one presented to the emergency room with a one-week history of numbness, paresthesia, and heaviness to both legs progressing to difficulty walking on the day of presentation. Although MRI brain and lumbar puncture were negative, electromyography (EMG) and nerve conduction studies (NCS) of the lower extremities and right arm performed revealed an abnormal study suggestive of a very mild, distal, motor, axonal polyneuropathy. Patient two presented on day 113 with bilateral foot numbness, left foot drop, unsteady gait, and pain in the left thigh, which progressed over two week to bilateral leg weakness, inability to walk, and numbness bilaterally in the hands, legs, and feet. Both patients received intravenous immunoglobulin (IVIG) 0.4 g/kg/day for 5 days for possible acute inflammatory demyelinating polyneuropathy (AIDP) likely related to NY-ESO-1 targeting T-cell therapy. After 3 and 5 doses, respectively, of IVIG, the patients reported improvement in symptoms and strength, and were later transferred to an inpatient rehabilitation facility to continue gaining strength. At patient one's neurology follow-up on day 95, she reported only mild left lower extremity (LLE) weakness and was gradually successfully regaining independence in motor function. At patient two's 9-month follow-up, the patient had regained normal function and independence. CONCLUSIONS: Given the expanding applications of immunotherapy in cancer management, clinicians should stay vigilant against the potential development of unusual but life-threatening immune-mediated toxicities.


Assuntos
Transferência Adotiva , Antígenos de Neoplasias/imunologia , Síndrome de Guillain-Barré/etiologia , Proteínas de Membrana/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Sarcoma Sinovial/terapia , Linfócitos T/transplante , Adulto , Feminino , Engenharia Genética , Humanos , Pessoa de Meia-Idade , Sarcoma Sinovial/imunologia
5.
ACS Chem Biol ; 14(9): 2035-2043, 2019 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-31433159

RESUMO

Linalyl diphosphate (LPP) is the postulated intermediate in the enzymatic cyclization of monoterpenes catalyzed by terpene synthases. LPP is considered an obligate intermediate due to the conformationally restrictive trans-C2-C3 double bond of the substrate, geranyl diphosphate (GPP), which precludes the proper positioning of carbons C1 and C6 to enable cyclization. However, because of the complexity of potential carbocation-mediated rearrangements in these enzymatic reactions, it has proven difficult to directly demonstrate the formation of LPP despite significant efforts. Here we synthesized a fluorinated substrate analog, 8,9-difluorogeranyl diphosphate (DFGPP), which is designed to allow initial ionization/isomerization and form the fluorinated equivalent of LPP (DFLPP) while preventing the subsequent ionization/cyclization to produce the α-terpinyl cation. Steady-state kinetic studies with the model enzyme (+)-limonene synthase (LS) under catalytic conditions show that the cyclization of DFGPP is completely blocked and a single linear product, difluoromyrcene, is produced. When crystals of apo-LS are soaked with DFGPP under conditions limiting turnover of the enzyme, we show, using X-ray crystallography, that DFLPP is produced in the enzyme active site and trapped in the crystals. Clear electron density is observed in the active site of the enzyme, but it cannot be appropriately fit with a model for the DFGPP substrate analog, whereas it can accommodate an extended conformation of DFLPP. This result supports the current model for monoterpene cyclization by providing direct evidence of LPP as an intermediate.


Assuntos
Monoterpenos Acíclicos/química , Difosfatos/química , Diterpenos/química , Inibidores Enzimáticos/química , Liases Intramoleculares/antagonistas & inibidores , Fosfatos de Poli-Isoprenil/química , Domínio Catalítico , Citrus sinensis/enzimologia , Cristalografia por Raios X , Difosfatos/síntese química , Diterpenos/síntese química , Ensaios Enzimáticos , Inibidores Enzimáticos/síntese química , Liases Intramoleculares/química
6.
Biochemistry ; 56(12): 1716-1725, 2017 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-28272876

RESUMO

The stereochemical course of monoterpene synthase reactions is thought to be determined early in the reaction sequence by selective binding of distinct conformations of the geranyl diphosphate (GPP) substrate. We explore here formation of early Michaelis complexes of the (+)-limonene synthase [(+)-LS] from Citrus sinensis using monofluorinated substrate analogues 2-fluoro-GPP (FGPP) and 2-fluoroneryl diphosphate (FNPP). Both are competitive inhibitors for (+)-LS with KI values of 2.4 ± 0.5 and 39.5 ± 5.2 µM, respectively. The KI values are similar to the KM for the respective nonfluorinated substrates, indicating that fluorine does not significantly perturb binding of the ligand to the enzyme. FGPP and FNPP are also substrates, but with dramatically reduced rates (kcat values of 0.00054 ± 0.00005 and 0.00024 ± 0.00002 s-1, respectively). These data are consistent with a stepwise mechanism for (+)-LS involving ionization of the allylic GPP substrate to generate a resonance-stabilized carbenium ion in the rate-limiting step. Crystals of apo-(+)-LS were soaked with FGPP and FNPP to obtain X-ray structures at 2.4 and 2.2 Å resolution, respectively. The fluorinated analogues are found anchored in the active site through extensive interactions involving the diphosphate, three metal ions, and three active-site Asp residues. Electron density for the carbon chains extends deep into a hydrophobic pocket, while the enzyme remains mostly in the open conformation observed for the apoprotein. While FNPP was found in multiple conformations, FGPP, importantly, was in a single, relatively well-defined, left-handed screw conformation, consistent with predictions for the mechanism of stereoselectivity in the monoterpene synthases.


Assuntos
Apoproteínas/química , Citrus sinensis/química , Cicloexenos/química , Diterpenos/química , Inibidores Enzimáticos/química , Liases Intramoleculares/química , Organofosfatos/química , Proteínas de Plantas/química , Terpenos/química , Apoproteínas/antagonistas & inibidores , Apoproteínas/genética , Apoproteínas/metabolismo , Domínio Catalítico , Citrus sinensis/enzimologia , Clonagem Molecular , Cristalografia por Raios X , Cicloexenos/metabolismo , Diterpenos/metabolismo , Ensaios Enzimáticos , Inibidores Enzimáticos/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Expressão Gênica , Liases Intramoleculares/antagonistas & inibidores , Liases Intramoleculares/genética , Liases Intramoleculares/metabolismo , Cinética , Ligantes , Limoneno , Modelos Moleculares , Organofosfatos/metabolismo , Proteínas de Plantas/antagonistas & inibidores , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fosfatos de Poli-Isoprenil/química , Fosfatos de Poli-Isoprenil/metabolismo , Domínios Proteicos , Estrutura Secundária de Proteína , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Estereoisomerismo , Terpenos/metabolismo
7.
Acta Pol Pharm ; 69(4): 725-37, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22876617

RESUMO

The objective of this study was to extend the GI residence time of the dosage form and to control the release of domperidone using directly compressible sustained release mucoadhesive matrix (SRMM) tablets. A 2-factor centre composite design (CCD) was employed to study the influence of independent variables like gum ghatti (GG) (X1) and hydroxylpropylmethyl cellulose K 15M (HPMC K 15M) (X2) on dependent variable like mucoadhesive strength, tensile strength, release exponent (n), t50 (time for 50% drug release), rel(10 h) (release after 10 h) and rel(18 h) (release after 18 h). Tablets were prepared by direct compression technology and evaluated for tablet parametric test (drug assay, diameter, thickness, hardness and tensile strength), mucoadhesive strength (using texture analyzer) and in vitro drug release studies. The tensile strength and mucoadhesive strength were found to be increased from 0.665 +/- 0.1 to 1.591 +/- 0.1 MN/cm2 (Z1 to Z9) and 10.789 +/- 0.985 to 50.924 +/- 1.150 N (Z1 to Z9), respectively. The release kinetics follows first order and Hixson Crowell equation indicating drug release following combination of diffusion and erosion. The n varies between 0.834 and 1.273, indicating release mechanism shifts from non fickian (anomalous release) to super case II, which depict that drug follows multiple drug release mechanism. The t50 time was found to increase from 5 +/- 0.12 to 11.4 +/- 0.14 h (Z1 to Z9) and release after 10 and 18 h decreases with increasing concentration of both polymers concluding with release controlling potential of polymers. The accelerated stability studies were performed on optimized formulation as per ICH guideline and the result showed that there was no significant change in tensile strength, mucoadhesive strength and drug assay.


Assuntos
Antieméticos/química , Domperidona/química , Antagonistas de Dopamina/química , Excipientes/química , Mucosa Gástrica/metabolismo , Gomas Vegetais/química , Adesividade , Animais , Antieméticos/metabolismo , Química Farmacêutica , Preparações de Ação Retardada , Domperidona/metabolismo , Antagonistas de Dopamina/metabolismo , Composição de Medicamentos , Excipientes/metabolismo , Dureza , Derivados da Hipromelose , Cinética , Metilcelulose/análogos & derivados , Metilcelulose/química , Modelos Químicos , Gomas Vegetais/metabolismo , Solubilidade , Suínos , Comprimidos , Tecnologia Farmacêutica , Resistência à Tração
8.
Polim Med ; 42(1): 49-59, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22783733

RESUMO

BACKGROUND: Fast melt tablets, also known as fast dissolving tablets, disintegrate instantaneously within the mouth and thus can be consumed without water. The present study was aimed to formulate fast melt tablets of nimesulide by using Ocimum Sanctum seeds as a natural tablet superdisintegrant. MATERIAL AND METHODS: Powdered Ocimum seeds were characterized for powder flow properties (bulk density, tapped density, Carr's consolidation index, Hausner ratio, angle of repose), swelling index, viscosity, pH, loss on drying and microbial load. The prepared tablets were evaluated for different tablet parametric tests, wetting time, water absorption ratio, effective pore radius, porosity, packing fraction, in vitro and in vivo disintegration time, in-vitro dissolution and stability studies. RESULTS: The swelling index was evaluated to be 1600. An appreciable effect of the natural material was seen on tablet hardness and friability. The water absorption ratio increased from 56.15 +/- 0.85 to 80.76 +/- 0.70 (A1-A4). Water uptake coupled natural polymer swelling could be the most probable mechanism for concentration dependent reduction in disintegration time by the Ocimum Sanctum seeds. Porosity of the formulated tablets was found to increase from batch A1-A4. The in vitro disintegration results were in line with in vivo disintegration results. The f2 values (in comparison with Nimulid MD) of 95.90 and 93.65 were obtained with A3 and A4 batches respectively. CONCLUSION: It could be concluded that Ocimum Sanctum seeds could be used as a natural superdisintegrant in the formulation of fast melt tablets.


Assuntos
Sementes/química , Sulfonamidas/química , Comprimidos/química , Administração Oral , Química Farmacêutica , Estabilidade de Medicamentos , Porosidade , Pós/química , Sementes/microbiologia , Solubilidade , Sulfonamidas/administração & dosagem , Resistência à Tração , Viscosidade , Água/química
9.
J Adv Pharm Technol Res ; 2(3): 163-9, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22171313

RESUMO

The aim of study was to prepare controlled release matrix mucoadhesive tablets of domperidone using Salvia plebeian gum as natural polymer. Tablets were formulated by direct compression technology employing the natural polymer in different concentrations (5, 10, 15 and 20% w/w). The prepared batches were evaluated for drug assay, diameter, thickness, hardness and tensile strength, swelling index, mucoadhesive strength (using texture analyzer) and subjected to in vitro drug release studies. Real-time stability studies were also conducted on prepared batches. In vitro drug release data were fitted in various release kinetic models for studying the mechanism of drug release. Tensile strength was found to increase from 0.808 ± 0.098 to 1.527 ± 0.10 mN/cm(2) and mucoadhesive strength increased from 13.673 ± 1.542 to 40.378 ± 2.345 N, with an increase in the polymer concentration from 5 to 20% (A1 to A4). Swelling index was reported to increase with both increase in the concentration of gum and the time duration. The in vitro drug release decreased from 97.76 to 83.4% (A1 to A4) with the increase in polymer concentration. The drug release from the matrix tablets was found to follow zero-order and Higuchi models, indicating the matrix-forming potential of natural polymer. The value of n was found to be between 0.5221 and 0.8992, indicating the involvement of more than one drug release mechanism from the formulation and possibly the combination of both diffusion and erosion. These research findings clearly indicate the potential of S. plebeian gum to be used as binder, release retardant and mucoadhesive natural material in tablet formulations.

10.
Sci Pharm ; 79(3): 653-72, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21886910

RESUMO

Ofloxacin is a synthetic chemotherapeutic antibiotic used for treatment of a variety of bacterial infections, but therapy suffers from low patients' compliance due to its unpleasant taste. This study was aimed to develop taste masked microspheres of ofloxacin using Eudragit and to prepare orodispersible tablets of the formulated microspheres using natural superdisintegrant. Taste masking Eudragit E100 microspheres were prepared by solvent evaporation technique with an entrapment efficiency ranging from 69.54 ± 1.98 to 86.52 ± 2.25%. DSC revealed no interaction between the drug and polymer. Microspheres prepared at a drug/polymer ratio of 1:4 and 1:5 revealed sufficient flow properties and better taste masking as compared to other ratios. Drug loaded microspheres were formulated as orodispersible tablets using locust bean gum as a natural superdisintegrant offering the advatages of biocompatibility and biodegrad-ability. The wetting time, water absorption ratio and in-vitro disintegration time of the tablets were found to range between 19 ± 2 to 10 ± 3 seconds, 59.11 ± 0.65 to 85.76 ± 0.96 and 22 ± 2 to 10 ± 2 seconds, respectively. The in-vitro ofloxacin release was about 97.25% within 2h. The results obtained from the study suggested the use of eudragit polymer for preparing ofloxacin loaded microspheres with an aim to mask the bitter taste of the drug and furthermore orodispersible tablets could be formulated using locust bean gum as a natural superdisintegrant.

11.
Polim Med ; 41(2): 23-34, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21866794

RESUMO

The present study was aimed to formulate and evaluate oral controlled release mucoadhesive matrix tablets of taro gum incorporating domperidone as model drug. Tablets were prepared by direct compression and were evaluated for bioadhesive strength and in vitro dissolution parameters. A central composite design for 2 factors, at 3 levels each, was employed to evaluate the effect of criti cal formulation variables, namely the amount of taro gum (X1) and PVP K 30 (X2), on mucoadhesive strength, tensile strength, release exponent (n) and t50 (time for 50% drug release). The mucoadhesive detachment force (evaluated using texture analyzer) was found to be 18.266, 54.684 and 65.904 N for A4, A5 and A6 batches of the formulated tablets. The polynomial equation indicates that taro gum has dominating effect on mucoadhesive strength and both X1 and X2 have almost equal and comparable effect on tensile strength. The drug release follows first order kinetics (release of drug depends on remaining concentration of drug) and shows best linearity (r2 = 0.983) with higuchi model. The release exponent (n) lies between 0.339 and 0.543 indicating drug release from the matrix tablets may be fickian or non fickian (anamolous) depending upon the concentration of natural polymer. T50 was 58, 140 and 220 minutes for A7, A8 and A9 batches showing overriding potential of taro gum but still the effect of PVP K 30 is noteworthy. PVP K 30 has indirect effect on all the factors by increasing tensile strength and making the tablet firm and intact.


Assuntos
Colocasia , Preparações de Ação Retardada/química , Gomas Vegetais/química , Comprimidos/química , Química Farmacêutica , Excipientes/química , Propriedades de Superfície , Resistência à Tração
12.
Polim Med ; 41(1): 17-28, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21739929

RESUMO

Orodispersible tablets disperse instantaneously in the mouth so that they can be swallowed without the aid of water. The aim of the present study was to formulate nimesulide orodispersible tablets using locust bean gum as a natural superdisintegrant. The gum was evaluated for powder flow properties, swelling index and loss on drying. Excellent powder flow properties were observed, swelling index was found to be 20 which indicated appreciable capability of locust bean gum to be used as superdisintegrant. The prepared tablets were evaluated against standard superdisintegrant i.e. cross-carmellose sodium. Disintegration time of tablets containing 10 % locust bean gum was found to be 13 seconds. The prepared batches were also evaluated for wetting time, water absorption ratio, effective pore radius, porosity, in vitro and in vivo disintegration time, in vitro release and stability studies. Wetting time was found to reduce from 19 +/- 2 to 11 +/- 3 sec (A1-A4) and 51 +/- 2 to 36 +/- 3 sec (B1-B4). Effective pore radius and porosity were found to be increase with increase in polymer concentration. The superdisintegrant property of locust bean gum may be due to concentration dependent wicking action leading to formation of porous structure which disintegrates the tablet within seconds. In-vivo results were complementary to in-vitro disintegration time results. The in-vitro release studies were compared against marketed nimesulide fast dissolving tablets (Nimulid MD). Stability studies showed that there was no significant change in hardness, friability, tensile strength and assay of the prepared formulations. The f2 values (in comparison with Nimulid MD) of 92.27 and 98.19 were obtained with A3 and A4 batches respectively.


Assuntos
Galactanos/química , Mananas/química , Gomas Vegetais/química , Sulfonamidas/química , Comprimidos/química , Química Farmacêutica , Composição de Medicamentos , Sulfonamidas/administração & dosagem
13.
Int J Pharm Investig ; 1(3): 192-8, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23071942

RESUMO

AIM: Orodispersible tablets also known as fast dissolving tablets disintegrate instantaneously within the mouth and thus can be consumed without water. The present study was aimed to formulate orodispersible tablets of nimesulide by using Lallemantia reylenne seeds as natural superdisintegrant. MATERIALS AND METHODS: Powdered lallemantia seeds were characterized for powder flow properties (bulk density, tapped density, carr's consolidation index, hausner ratio, angle of repose), swelling index, viscosity, pH, and loss on drying. The prepared tablets were evaluated for different tablet parametric tests, wetting time, water absorption ratio, effective pore radius, porosity, packing fraction, in vitro and in vivo disintegration time, in vitro dissolution and stability studies. RESULTS AND DISCUSSION: Increase in Lallementia reylenne concentration had an appreciable effect on tablet hardness and friability which clearly indicated binding potential of the seeds. Water absorption ratio increased with increase in Lallemantia reylenne concentration from batch A1 to A4. Water uptake coupled natural polymer swelling could be the most probable mechanism for concentration dependent reduction in disintegration time by the Lallemantia reylenne seeds. Porosity of the formulated tablets was found to increase from batch A1-A4. The in vitro disintegration results were in line with in vivo disintegration results. CONCLUSION: It could be concluded that Lallemantia reylenne seeds could be used as natural superdisintegrant in the formulation of orodispersible tablets.

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