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EBNA1 is an Epstein Barr virus (EBV) protein expressed in all EBV-associated cancers. EBNA1 plays a critical role in the replication and maintenance of EBV episomes in latently infected cells. VK-2019 was developed as a highly specific inhibitor of EBNA1 DNA binding activity and is currently in phase 1 development as a treatment for EBV-associated carcinomas. A sensitive and reliable method was developed to quantify VK-2019 in human plasma using liquid chromatography with tandem mass spectrometry to perform detailed pharmacokinetic studies. VK-2019 was extracted from plasma using protein precipitation with acetonitrile. Separation of VK-2019, two purported metabolites, and the internal standard, VK-2019-d6, was achieved with a Zorbax XDB C18 column using a gradient flow over 6 min. VK-2019 was detected using a SCIEX 4500 triple quadrupole mass spectrometer operating in positive electrospray ionization mode. The assay range was 0.5-500 ng/mL and proved to be accurate and precise. Dilutions of 1:10 were accurately quantified. VK-2019 was stable in plasma at -70°C for approximately 18 months. The method was applied to assess the total plasma concentrations of VK-2019 in a patient who received a single and multiple oral daily doses of 120 mg.
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Antineoplásicos , Antígenos Nucleares del Virus de Epstein-Barr , Humanos , Antineoplásicos/química , Cromatografía Líquida de Alta Presión/métodos , Cromatografía Liquida/métodos , Infecciones por Virus de Epstein-Barr , Herpesvirus Humano 4 , Reproducibilidad de los Resultados , Espectrometría de Masa por Ionización de Electrospray/métodos , Espectrometría de Masas en Tándem/métodos , Antígenos Nucleares del Virus de Epstein-Barr/química , Antígenos Nucleares del Virus de Epstein-Barr/farmacologíaRESUMEN
The Bcl-2 family small molecule inhibitor navitoclax is being clinically evaluated to treat multiple cancers including lymphoid malignancies and small cell lung cancer. A sensitive and reliable method was developed to quantitate navitoclax in human plasma using liquid chromatography with tandem mass spectrometry with which to perform detailed pharmacokinetic studies. Sample preparation involved protein precipitation using acetonitrile. Separation of navitoclax and the internal standard, navitoclax-d8, was achieved with a Waters Acquity UPLC BEH C18 column using isocratic flow over a 3 min total analytical run time. A SCIEX 4500 triple quadrupole mass spectrometer operated in positive electrospray ionization mode was used for the detection of navitoclax. The assay range was 5-5,000 ng/ml and proved to be accurate (89.5-104.9%) and precise (CV ≤ 11%). Long-term frozen plasma stability for navitoclax at -70°C was at least 34 months. The method was applied for the measurement of total plasma concentration of navitoclax in a patient receiving a 250 mg daily oral dose.
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Compuestos de Anilina , Sulfonamidas , Cromatografía Líquida de Alta Presión/métodos , Cromatografía Liquida/métodos , Humanos , Reproducibilidad de los Resultados , Espectrometría de Masas en Tándem/métodosRESUMEN
Navtemadlin is an orally bioavailable small molecule that blocks the protein-protein interaction between murine double minute 2 protein (MDM2) and the tumor suppressor protein p53, leading to p53-mediated cell cycle arrest and apoptosis. It is being evaluated in clinical trials for a variety of malignancies, both as a single agent and in combination regimens. A sensitive, robust LC-tandem mass spectrometry (LC-MS/MS) method was developed to quantitate navtemadlin in plasma, and this method was also validated using brain tissue homogenate. Sample preparation involved protein precipitation of plasma or brain tissue homogenate using acetonitrile. Navtemadlin, navtemadlin glucuronide, and the internal standard, D6 -navtemadlin, were separated from microsomal incubation extracts using gradient elution and a ZORBAX XDB C18 column. Analytes were detected using a SCIEX 5500 triple quadrupole mass spectrometer in positive electrospray ionization mode. The assay range of 1-1000 ng/mL was shown to be accurate (96.1-102.0% and 95.7-104%) and precise (coefficient of variation ≤ 10.6% and ≤ 6.6%) in plasma and brain tissue homogenate, respectively. An 8000 ng/mL navtemadlin sample diluted 1:10 (v/v) with plasma was also accurately quantitated. Navtemadlin has been stable in frozen plasma at -70°C for at least 20 months. This validated LC-MS/MS method was applied to determine navtemadlin concentrations in plasma and brain tissue samples from two separate patients receiving 120 mg/day navtemadlin on protocol ABTC1604.
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Espectrometría de Masas en Tándem , Proteína p53 Supresora de Tumor , Acetonitrilos , Animales , Encéfalo/metabolismo , Cromatografía Líquida de Alta Presión/métodos , Cromatografía Liquida/métodos , Glucurónidos/metabolismo , Humanos , Ratones , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Reproducibilidad de los Resultados , Espectrometría de Masas en Tándem/métodos , Proteína p53 Supresora de Tumor/metabolismoRESUMEN
Preterm birth (PTB) affects nearly 15 million infants each year. Of these PTBs, >25% are a result of inflammation or infection. Animal models have improved our understanding of the mechanisms leading to PTB. Prior work has described induction of intrauterine inflammation in mice with a single injection of lipopolysaccharide (LPS). Herein, we have improved the reproducibility and potency of LPS in the model using two injections distal to the cervix. An in vivo imaging system revealed more uniform distribution of Evans Blue Dye using a double distal injection (DDI) approach compared with a single proximal injection (SPI). Endotoxin concentrations in vaginal lavage fluid from SPI dams were significantly higher than from DDI dams. At equivalent LPS doses, DDI consistently induced more PTB than SPI, and DDI showed a linear dose-response, whereas SPI did not. Gene expression in myometrial tissue revealed increased levels of inflammatory markers in dams that received LPS DDI compared with LPS SPI. The SPI group showed more significant overexpression in cervical remodeling genes, likely due to the leakage of LPS from the uterine horns through the cervix. The more reliable PTB induction and uniform uterine exposure provided by this new model will be useful for further studying fetal outcomes and potential therapeutics for the prevention of inflammation-induced PTB.
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Modelos Animales de Enfermedad , Inflamación/complicaciones , Lipopolisacáridos/toxicidad , Miometrio/patología , Nacimiento Prematuro/etiología , Efectos Tardíos de la Exposición Prenatal/etiología , Animales , Femenino , Inflamación/inducido químicamente , Inflamación/patología , Ratones , Miometrio/efectos de los fármacos , Miometrio/inmunología , Embarazo , Nacimiento Prematuro/patología , Efectos Tardíos de la Exposición Prenatal/patología , Útero/efectos de los fármacosRESUMEN
BACKGROUND: Epigenetic abnormalities are manifold in all solid tumors and include changes in chromatin configuration and DNA methylation. The authors designed a phase 1 study to evaluate the oral DNA methyltransferase inhibitor CC-486 combined with the histone deacetylase inhibitor romidepsin in advanced solid tumors with dose expansion to further evaluate pharmacodynamics and possible clinical benefit of the recommended phase 2 dose (RP2D). METHODS: This was a phase 1 study with a 3 + 3 dose-escalation design and an expansion phase for patients with virally mediated cancers. The disease control rate (DCR) was the primary outcome for the expansion cohort. Correlative studies included long interspersed nucleotide element 1 (LINE-1) methylation and drug exposure in blood samples (clinicaltrials.gov identifier NCT01537744). RESULTS: Fourteen patients were enrolled in the dose-escalation portion at 3 dose levels. Three patients experienced dose-limiting toxicities; the RP2D was oral CC-486 300 mg daily on days 1 through 14 and romidepsin 8 mg/m2 on days 8 and 15. Because of slow accrual into the expansion phase, the trial was closed after 4 patients enrolled. Common toxicities of the combination included nausea (83.3%), anorexia (72.2%), fatigue (61.1%), and constipation (55.6%). There were 12 patients evaluable for response, 5 with stable disease, of whom 2 received >4 cycles; there were no responses. Exposure to CC-486 and romidepsin was consistent with prior data. LINE-1 methylation on C1D8 was significantly reduced (mean, -6.23; 95% CI, -12.23, -0.24; P = .04). CONCLUSIONS: Although, at the RP2D, the combination of CC-486 and romidepsin was tolerable, no significant anticancer activity was observed. Significant demethylation in post-treatment circulating tumor DNA and biopsies provided proof of target acquisition.
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Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Metilasas de Modificación del ADN/antagonistas & inhibidores , Depsipéptidos/efectos adversos , Inhibidores de Histona Desacetilasas/efectos adversos , Neoplasias/tratamiento farmacológico , Administración Oral , Adulto , Anciano , Anciano de 80 o más Años , Anorexia/inducido químicamente , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Azacitidina/administración & dosificación , Azacitidina/efectos adversos , Depsipéptidos/administración & dosificación , Depsipéptidos/farmacocinética , Esquema de Medicación , Femenino , Inhibidores de Histona Desacetilasas/administración & dosificación , Inhibidores de Histona Desacetilasas/farmacocinética , Humanos , Elementos de Nucleótido Esparcido Largo/genética , Masculino , Dosis Máxima Tolerada , Metiltransferasas/antagonistas & inhibidores , Persona de Mediana Edad , Náusea/inducido químicamenteRESUMEN
Purpose: A proposed mechanism for the enhanced effectiveness of hyperthermia and doxorubicin (Dox) combinations is increased intracellular Dox concentrations resulting from heat-induced cell stress. The purpose of this study was to determine whether specific varied Dox and heat combinations produce measurable effects greater than the additive combination, and whether these effects can be attributed to heat-induced increases in intracellular Dox concentrations. Methods: HCT116, HT29 and CT26 cells were exposed to Dox and water bath heating independently. A clonogenic survival assay was used to determine cell killing and intracellular Dox concentrations were measured in HCT116 cells with mass spectrometry. Cells were exposed to heating at 42 °C (60 min) and 0.5 µg/ml of Dox at varying intervals. Synergy was determined by curve-fitting and isobologram analysis. Results: All cell lines displayed synergistic effects of combined heating and Dox. A maximum synergistic effect was achieved with simultaneous cell exposure to Dox and heat. For exposures at 42 °C, the synergistic effect was most pronounced at Dox concentrations <0.5 µg/ml. Increased intracellular concentrations of Dox in HCT116 cells caused by heat-stress did not generate a concomitant thermal enhancement. Conclusions: Simultaneous exposure of HCT116 cells to heating and Dox is more effective than sequential exposure. Heat-induced cell responses are accompanied by increased intracellular Dox concentrations; however, clonogenic survival data do not support this as the cause for synergistic cytotoxicity.
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Antibióticos Antineoplásicos/administración & dosificación , Doxorrubicina/administración & dosificación , Calor , Transporte Biológico , Muerte Celular , Línea Celular Tumoral , HumanosRESUMEN
The blood-brain barrier (BBB) significantly reduces the delivery of many systemically administered agents to the central nervous system. Although temozolomide is the only chemotherapy to improve survival in patients with glioblastoma, its concentration in brain is only 20 % of that in blood. Regadenoson, an FDA approved adenosine receptor agonist used for cardiac stress testing, transiently disrupts rodent BBB allowing high molecular weight dextran (70 kD) to enter the brain. This study was conducted to determine if regadenoson could facilitate entry of temozolomide into normal rodent brain. Temozolomide (50 mg/kg) was administered by oral gavage to non-tumor bearing F344 rats. Two-thirds of the animals received a single dose of intravenous regadenoson 60-90 min later. All animals were sacrificed 120 or 360 min after temozolomide administration. Brain and plasma temozolomide concentrations were determined using HPLC/MS/MS. Brain temozolomide concentrations were significantly higher at 120 min when it was given with regadenoson versus alone (8.1 ± 2.7 and 5.1 ± 3.5 µg/g, P < 0.05). A similar trend was noted in brain:plasma ratios (0.45 ± 0.08 and 0.29 ± 0.09, P < 0.05). Brain concentrations and brain:plasma ratios were not significantly different 360 min after temozolomide administration. No differences were seen in plasma temozolomide concentrations with or without regadenoson. These results suggest co-administration of regadenoson with temozolomide results in 60% higher temozolomide levels in normal brain without affecting plasma concentrations. This novel approach to increasing intracranial concentrations of systemically administered agents has potential to improve the efficacy of chemotherapy in neuro-oncologic disorders.
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Antineoplásicos Alquilantes/administración & dosificación , Barrera Hematoencefálica/efectos de los fármacos , Encéfalo/metabolismo , Dacarbazina/análogos & derivados , Sistemas de Liberación de Medicamentos , Purinas/farmacología , Pirazoles/farmacología , Animales , Antineoplásicos Alquilantes/sangre , Antineoplásicos Alquilantes/farmacocinética , Dacarbazina/administración & dosificación , Dacarbazina/sangre , Dacarbazina/farmacocinética , Femenino , Ratas , Ratas Endogámicas F344 , Espectrometría de Masas en Tándem , Temozolomida , Distribución TisularRESUMEN
The DNA methyltransferase inhibitor 5-azacytidine is being evaluated clinically as an oral formulation to treat various solid tumors. A sensitive, reliable method was developed to quantitate 5-azacytidine using LC-MS/MS to perform detailed pharmacokinetic studies. The drug of interest was extracted from plasma using Oasis MCX ion exchange solid-phase extraction 96-well plates. Chromatographic separation was achieved with a YMC J'sphere M80 C18 column and isocratic elution with a methanol-water-formic acid (15:85:0.1, v/v/v) mobile phase over a 7 min total analytical run time. An AB Sciex 5500 triple quadrupole mass spectrometer operated in positive electrospray ionization mode was used for the detection of 5-azacytidine. The assay range was 5-500 ng/mL and proved to be accurate (97.8-109.1%) and precise (CV ≤ 9.8%). Tetrahydrouridine was used to stabilize 5-azacytidine in blood/plasma samples. With the addition of tetrahydrouridine, long-term frozen plasma stability for 5-azacytidine at -70°C has been determined for at least 323 days. The method was applied for the measurement of total plasma concentrations of 5-azacytidine in a cancer patient receiving a 300 mg oral daily dose.
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Antimetabolitos Antineoplásicos/sangre , Azacitidina/sangre , Cromatografía Liquida/métodos , Espectrometría de Masas en Tándem/métodos , Antimetabolitos Antineoplásicos/química , Antimetabolitos Antineoplásicos/farmacocinética , Antimetabolitos Antineoplásicos/uso terapéutico , Azacitidina/química , Azacitidina/farmacocinética , Azacitidina/uso terapéutico , Estabilidad de Medicamentos , Humanos , Neoplasias/tratamiento farmacológico , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
BACKGROUND: Antiviral therapies that target herpesviruses are clinically important. Nelfinavir is a protease inhibitor that targets the human immunodeficiency virus (HIV) aspartyl protease. Previous studies demonstrated that this drug could also inhibit Kaposi's sarcoma-associated herpesvirus (KSHV) production. Our laboratory demonstrated nelfinavir can effectively inhibit herpes simplex virus type 1 (HSV-1) replication. For HSV-1 we were able to determine that virus capsids were assembled and exited the nucleus but did not mature in the cytoplasm indicating the drug inhibited secondary envelopment of virions. METHODS: For KSHV, we recently derived a tractable cell culture system that allowed us to analyze the virus replication cycle in greater detail. We used this system to further define the stage at which nelfinavir inhibits KSHV replication. RESULTS: We discovered that nelfinavir inhibits KSHV extracellular virus production. This was seen when the drug was incubated with the cells for 3 days and when we pulsed the cells with the drug for 1-5 min. When KSHV infected cells exposed to the drug were examined using ultrastructural methods there was an absence of mature capsids in the nucleus indicating a defect in capsid assembly. Because nelfinavir influences the integrated stress response (ISR), we examined the expression of viral proteins in the presence of the drug. We observed that the expression of many were significantly changed in the presence of drug. The accumulation of the capsid triplex protein, ORF26, was markedly reduced. This is an essential protein required for herpesvirus capsid assembly. CONCLUSIONS: Our studies confirm that nelfinavir inhibits KSHV virion production by disrupting virus assembly and maturation. This is likely because of the effect of nelfinavir on the ISR and thus protein synthesis and accumulation of the essential triplex capsid protein, ORF26. Of interest is that inhibition requires only a short exposure to drug. The source of infectious virus in saliva has not been defined in detail but may well be lymphocytes or other cells in the oral mucosa. Thus, it might be that a "swish and spit" exposure rather than systemic administration would prevent virion production.
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PURPOSE: High-dose intravenous vitamin C(HDIVC) administered to produce pharmacologic concentrations shows promise in preclinical models and small clinical trials, but larger prospective randomized trials are lacking. We evaluated the clinical benefit of combining HDIVC with docetaxel in patients with progressive metastatic castration-resistant prostate cancer(mCRPC). PATIENTS AND METHODS: This double-blind, placebo-controlled phase 2 trial randomized 47 patients 2:1 to receive docetaxel(75mg/m2 IV) with either HDIVC(1g/kg) or placebo. Co-primary endpoints were PSA50 response and adverse event rates. Secondary endpoints included overall survival, radiographic progression-free survival(rPFS), and quality-of-life measured using the Functional Assessment of Cancer Therapy-Prostate(FACT-P) instrument. Correlative analyses included pharmacokinetics and oxidative stress markers. RESULTS: Eighty-nine percent of patients previously had 3 or more lines of therapy. PSA50 response rate was 41% in the HDIVC group and 33% in the placebo group(p=0.44), with comparable adverse event rates in both groups. There were no significant differences in FACT-P scores. Median rPFS was not significantly different between the HDIVC and placebo groups, with durations of 10.1 and 10.0 months(HR:1.35; 95%CI, 0.66-2.75, p=0.40). Median overall survival was 15.2 months in the HDIVC group and 29.5 in the placebo group(HR:1.98; 95%CI, 0.85-4.58, p=0.11). HDIVC did not decrease F2-isoprostanes, indicators of oxidative stress. The study was suspended after pre-specified interim analysis indicated futility in achieving primary endpoints. CONCLUSIONS: In this patient population, combining HDIVC with docetaxel did not improve PSA response, toxicity, or other clinical outcomes compared to docetaxel alone. Findings do not support the routine use of HDIVC in mCRPC treatment outside of clinical trials.
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Although DNA methyltransferase inhibitors (DNMTis), such as azacitidine and decitabine, are used extensively in the treatment of myelodysplastic syndromes and acute myeloid leukemia, there remain unanswered questions about DNMTi's mechanism of action and predictors of clinical response. Because patients often remain on single-agent DNMTis or DNMTi-containing regimens for several months before knowing whether clinical benefit can be achieved, the development and clinical validation of response-predictive biomarkers represents an important unmet need in oncology. In this review, we will summarize the clinical studies that led to the approval of azacitidine and decitabine, as well as the real-world experience with these drugs. We will then focus on biomarker development for DNMTis-specifically, efforts at determining exposure-response relationships and challenges that remain impacting the broader clinical translation of these methods. We will highlight recent progress in liquid-chromatography tandem mass spectrometry technology that has allowed for the simultaneous measurement of decitabine genomic incorporation and global DNA methylation, which has significant potential as a mechanism-of-action based biomarker in patients on DNMTis. Last, we will cover important research questions that need to be addressed in order to optimize this potential biomarker for clinical use.
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Azacitidina , Leucemia Mieloide Aguda , Humanos , Decitabina/uso terapéutico , Azacitidina/uso terapéutico , Azacitidina/farmacología , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/uso terapéutico , Leucemia Mieloide Aguda/tratamiento farmacológico , Metilación de ADN , ADN , MetiltransferasasRESUMEN
PURPOSE: It has become increasingly clear that new multiagent combination regimens are required to improve survival rates in acute myeloid leukemia (AML). We recently reported that ART631, a first-in-class 2-carbon-linked artemisinin-derived dimer (2C-ART), was not only efficacious as a component of a novel three-drug combination regimen to treat AML, but, like other synthetic artemisinin derivatives, demonstrated low clinical toxicity. However, we ultimately found ART631 to have suboptimal solubility and stability properties, thus limiting its potential for clinical development. METHODS: We assessed 22 additional 2C-ARTs with documented in vivo antimalarial activity for antileukemic efficacy and physicochemical properties. Our strategy involved culling out 2C-ARTs inferior to ART631 with respect to potency, stability, and solubility in vitro, and then validating in vivo pharmacokinetics, pharmacodynamics, and efficacy of one 2C-ART lead compound. RESULTS: Of the 22 2C-ARTs, ART714 was found to have the most optimal in vitro solubility, stability, and antileukemic efficacy, both alone and in combination with the BCL2 inhibitor venetoclax (VEN) and the kinase inhibitor sorafenib (SOR). ART714 was also highly effective in combination with VEN and the FMS-like tyrosine kinase 3 inhibitor gilteritinib (GILT) against MOLM14 AML xenografts. CONCLUSION: We identified ART714 as our best-in-class antileukemic 2C-ART, based on in vitro potency and pharmacologic properties. We established its in vivo pharmacokinetics and demonstrated its in vitro cooperativity with VEN and SOR and in vivo activities of combinations of ART714, VEN, and GILT. Additional research is indicated to define the optimal niche for the use of ART714 in treatment of AML.
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Antimaláricos , Antineoplásicos , Artemisininas , Leucemia Mieloide Aguda , Humanos , Carbono/uso terapéutico , Antineoplásicos/farmacología , Antimaláricos/farmacología , Sorafenib/uso terapéutico , Artemisininas/farmacología , Leucemia Mieloide Aguda/tratamiento farmacológicoRESUMEN
Many patients with diabetic eye disease respond inadequately to anti-VEGF therapies, implicating additional vasoactive mediators in its pathogenesis. We demonstrate that levels of angiogenic proteins regulated by HIF-1 and -2 remain elevated in the eyes of people with diabetes despite treatment with anti-VEGF therapy. Conversely, by inhibiting HIFs, we normalized the expression of multiple vasoactive mediators in mouse models of diabetic eye disease. Accumulation of HIFs and HIF-regulated vasoactive mediators in hyperglycemic animals was observed in the absence of tissue hypoxia, suggesting that targeting HIFs may be an effective early treatment for diabetic retinopathy. However, while the HIF inhibitor acriflavine prevented retinal vascular hyperpermeability in diabetic mice for several months following a single intraocular injection, accumulation of acriflavine in the retina resulted in retinal toxicity over time, raising concerns for its use in patients. Conversely, 32-134D, a recently developed HIF inhibitor structurally unrelated to acriflavine, was not toxic to the retina, yet effectively inhibited HIF accumulation and normalized HIF-regulated gene expression in mice and in human retinal organoids. Intraocular administration of 32-134D prevented retinal neovascularization and vascular hyperpermeability in mice. These results provide the foundation for clinical studies assessing 32-134D for the treatment of patients with diabetic eye disease.
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Diabetes Mellitus Experimental , Retinopatía Diabética , Neovascularización Retiniana , Humanos , Ratones , Animales , Acriflavina/metabolismo , Acriflavina/farmacología , Acriflavina/uso terapéutico , Diabetes Mellitus Experimental/metabolismo , Retina/metabolismo , Neovascularización Retiniana/metabolismo , Retinopatía Diabética/tratamiento farmacológico , Retinopatía Diabética/genética , Retinopatía Diabética/metabolismo , Hipoxia/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismoRESUMEN
Effective eye drop delivery systems for treating diseases of the posterior segment have yet to be clinically validated. Further, adherence to eye drop regimens is often problematic due to the difficulty and inconvenience of repetitive dosing. Here, we describe a strategy for topically dosing a peptide-drug conjugate to achieve effective and sustained therapeutic sunitinib concentrations to protect retinal ganglion cells (RGCs) in a rat model of optic nerve injury. We combined two promising delivery technologies, namely, a hypotonic gel-forming eye drop delivery system, and an engineered melanin binding and cell-penetrating peptide that sustains intraocular drug residence time. We found that once daily topical dosing of HR97-SunitiGel provided up to 2 weeks of neuroprotection after the last dose, effectively doubling the therapeutic window observed with SunitiGel. For chronic ocular diseases affecting the posterior segment, the convenience of an eye drop combined with intermittent dosing frequency could result in greater patient adherence, and thus, improved disease management.
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Sustained drug delivery strategies have many potential benefits for treating a range of diseases, particularly chronic diseases that require treatment for years. For many chronic ocular diseases, patient adherence to eye drop dosing regimens and the need for frequent intraocular injections are significant barriers to effective disease management. Here, we utilize peptide engineering to impart melanin binding properties to peptide-drug conjugates to act as a sustained-release depot in the eye. We develop a super learning-based methodology to engineer multifunctional peptides that efficiently enter cells, bind to melanin, and have low cytotoxicity. When the lead multifunctional peptide (HR97) is conjugated to brimonidine, an intraocular pressure lowering drug that is prescribed for three times per day topical dosing, intraocular pressure reduction is observed for up to 18 days after a single intracameral injection in rabbits. Further, the cumulative intraocular pressure lowering effect increases ~17-fold compared to free brimonidine injection. Engineered multifunctional peptide-drug conjugates are a promising approach for providing sustained therapeutic delivery in the eye and beyond.
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Sistemas de Liberación de Medicamentos , Melaninas , Animales , Conejos , Tartrato de Brimonidina , Péptidos , Aprendizaje AutomáticoRESUMEN
The global transcription inhibitor terameprocol is being evaluated clinically as an oral formulation to treat high-grade glioma. A sensitive, reliable method was developed to quantitate terameprocol using LC-MS/MS to perform detailed pharmacokinetic studies. Sample preparation involved protein precipitation using acetonitrile. Separation of terameprocol and the internal standard, Sorafenib-methyl-d3, was achieved with a Zorbax XDB C18 column (2.1 × 50 mm, 3.5 µm) and gradient elution over a 2-minute total analytical run time. A SCIEX 4500 or SCIEX 5500 triple quadrupole mass spectrometer operated in positive electrospray ionization mode was used for terameprocol detection. The assay range of 5-1000 ng/mL was demonstrated to be accurate (92.7-107.4%) and precise (CV ≤ 11.3%). A sample diluted 1:10 (v/v) was accurately quantitated. Terameprocol in plasma has been proven stable for at least 20 months when stored at -70 °C. The method was applied to the measurement of total plasma concentrations of terameprocol in a patient with a high-grade glioma receiving a 300 mg oral dose.
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Espectrometría de Masa por Ionización de Electrospray , Espectrometría de Masas en Tándem , Cromatografía Líquida de Alta Presión , Cromatografía Liquida , Humanos , Masoprocol/análogos & derivados , Reproducibilidad de los ResultadosRESUMEN
Vistusertib is an orally bioavailable mTOR inhibitor that is being studied in clinical trials. A novel reliable method was developed to quantitate vistusertib using LC-MS/MS to explore drug exposure-response relationships. Sample preparation involved protein precipitation using acetonitrile. Separation of vistusertib and the internal standard, AZD8055, was achieved with a Waters Acquity UPLC BEH C18 column utilizing isocratic elution over a 3 min total analytical run time. A SCIEX 4500 triple quadrupole mass spectrometer operated in positive electrospray ionization mode was used for the detection of vistusertib. The assay range was 5-5000 ng/mL and proved to be accurate (98.7-105.7%) and precise (CV ≤ 10.5%). A 40,000 ng/mL sample that was diluted 1:10 (v/v) with plasma was accurately quantitated. Long-term frozen plasma stability for vistusertib at -70 °C has been determined for at least 29 months. The method was applied for the measurement of plasma concentrations of vistusertib in a patient a solid tumor receiving 35 mg twice daily dose orally.
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Neoplasias , Espectrometría de Masas en Tándem , Benzamidas , Cromatografía Líquida de Alta Presión , Cromatografía Liquida , Humanos , Morfolinas , Pirimidinas , Reproducibilidad de los ResultadosRESUMEN
Extracellular vesicles (EVs), or exosomes, play a pivotal role in tumor growth and metastasis, such as in the case of Kaposi Sarcoma. By loading tumor-derived EVs with chemotherapeutic drugs, we noted that their pro-tumor/pro-angiogenic phenotype was converted into an anti-tumor phenotype in vivo. Drug concentration in EVs was significantly higher than in clinically approved liposome formulation, as retention was facilitated by the presence of miRNAs inside the natural EVs. This demonstrates a new mechanism by which to increase the payload capacity of nanoparticles. By exploiting the targeting preferences of tumor-derived EVs, chemotherapeutics can be directed to specifically poison the cells and the microenvironment that enables metastasis.
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Hepatocellular carcinoma (HCC) is a major cause of cancer mortality worldwide and available therapies, including immunotherapies, are ineffective for many patients. HCC is characterized by intratumoral hypoxia, and increased expression of hypoxia-inducible factor 1α (HIF-1α) in diagnostic biopsies is associated with patient mortality. Here we report the development of 32-134D, a low-molecular-weight compound that effectively inhibits gene expression mediated by HIF-1 and HIF-2 in HCC cells, and blocks human and mouse HCC tumor growth. In immunocompetent mice bearing Hepa1-6 HCC tumors, addition of 32-134D to anti-PD1 therapy increased the rate of tumor eradication from 25% to 67%. Treated mice showed no changes in appearance, behavior, body weight, hemoglobin, or hematocrit. Compound 32-134D altered the expression of a large battery of genes encoding proteins that mediate angiogenesis, glycolytic metabolism, and responses to innate and adaptive immunity. This altered gene expression led to significant changes in the tumor immune microenvironment, including a decreased percentage of tumor-associated macrophages and myeloid-derived suppressor cells, which mediate immune evasion, and an increased percentage of CD8+ T cells and natural killer cells, which mediate antitumor immunity. Taken together, these preclinical findings suggest that combining 32-134D with immune checkpoint blockade may represent a breakthrough therapy for HCC.