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1.
ACS Nano ; 17(3): 2212-2221, 2023 02 14.
Article in English | MEDLINE | ID: mdl-36701244

ABSTRACT

Nanoparticle biodistribution in vivo is an essential component to the success of nanoparticle-based drug delivery systems. Previous studies with fluorescently labeled expansile nanoparticles, or "eNPs", demonstrated a high specificity of eNPs to tumors that is achieved through a materials-based targeting strategy. However, fluorescent labeling techniques are primarily qualitative in nature and the gold-standard for quantitative evaluation of biodistribution is through radiolabeling. In this manuscript, we synthesize 14C-labeled eNPs to quantitatively evaluate the biodistribution of these particles in a murine model of intraperitoneal mesothelioma via liquid scintillation counting. The results demonstrate a strong specificity of eNPs for tumors that lasts one to 2 weeks postinjection with an overall delivery efficiency to the tumor tissue of 30% of the injected dose which is congruent with prior reports of preclinical efficacy of the technology. Importantly, the route of administration is essential to the eNP's material-based targeting strategy with intraperitoneal administration leading to tumoral accumulation while, in contrast, intravenous administration leads to rapid clearance via the reticuloendothelial system and low tumoral accumulation. A comparison against nanoparticle delivery systems published over the past decade shows that the 30% tumoral delivery efficiency of the eNP is significantly higher than the 0.7% median delivery efficiency of other systems with sufficient quantitative data to define this metric. These results lay a foundation for targeting intraperitoneal tumors and encourage efforts to explore alternative, nonintravenous routes, of delivery to accelerate the translation of nanoparticle therapies to the clinic.


Subject(s)
Mesothelioma, Malignant , Mesothelioma , Nanoparticles , Mice , Humans , Animals , Tissue Distribution , Mesothelioma, Malignant/drug therapy , Injections, Intraperitoneal
2.
Inorg Chem ; 60(19): 14679-14686, 2021 Oct 04.
Article in English | MEDLINE | ID: mdl-34555283

ABSTRACT

Developing low-melting alkali salts is of interest for both battery electrolytes and inorganic ionic liquids. In this study, we report a series of asymmetric alkali-metal sulfonamide salts based upon the (3-methoxypropyl)((trifluoromethyl)sulfonyl)amide (MPSA) anion. This family of salts features an unusual melting point trend, where the melting point of the salts decreases as the cation increases in size from Li to K but then the melting point increases as the cation further increases in size from K to Cs. Analyses of single crystals reveal that the unusual higher melting points of RbMPSA and CsMPSA in comparison to KMPSA can be attributed to the greater cation-cation distances as well as the increased rigidity of anion-cation coordination due to an increase in cyclic structures in comparison to KMPSA. Exceptionally, KMPSA features a very low melting point of only 50.79 ± 0.31 °C. This low melting point can be attributed to a relatively high degree of disorder, an unusual uncoordinated ether moiety, and a very short K-K distance of only 3.4348(7) Å among other factors, which is supported by the low cohesive energy and small elastic moduli among the rest according to density functional theory (DFT) calculations. The low melting point of KMPSA makes it interesting for low-temperature ionic liquids.

3.
J Control Release ; 337: 144-154, 2021 09 10.
Article in English | MEDLINE | ID: mdl-34280414

ABSTRACT

One of the foremost challenges in translating nanoparticle technologies to the clinic is the requirement to produce materials on a large-scale. Scaling nanoparticle production methods is often non-trivial, and the success of these endeavors is frequently governed by whether or not an intermediate level of production, i.e., "pilot-scale" production, can be achieved. Pilot-scale production at the one-liter scale serves as a proof-of-concept that large-scale production will be possible. Here, we describe the pilot-scale production of the expansile nanoparticle (eNP) technology including verification of activity and efficacy following scaleup. We describe the challenges of sonication-based emulsification procedures and how these were overcome by use of a Microfluidizer technology. We also describe the problem-solving process that led to pre-polymerization of the nanoparticle polymer-a fundamental change from the lab-scale and previously published methods. Furthermore, we demonstrate good control over particle diameter, polydispersity and drug loading and the ability to sterilize the particles via filtration using this method. To facilitate long-term storage of these larger quantities of particles, we investigated six lyoprotectants and determined that sucrose is the most compatible with the current system. Lastly, we demonstrate that these changes to the manufacturing method do not adversely affect the swelling functionality of the particles, their highly specific localization to tumors, their non-toxicity in vivo or their efficacy in treating established intraperitoneal mesothelioma xenografts.


Subject(s)
Mesothelioma, Malignant , Mesothelioma , Nanoparticles , Humans , Polymers , Sonication
4.
Gastroenterology ; 161(5): 1475-1486, 2021 11.
Article in English | MEDLINE | ID: mdl-34310978

ABSTRACT

BACKGROUND & AIMS: Increased de novo lipogenesis creates excess intrahepatic fat and lipotoxins, propagating liver damage in nonalcoholic steatohepatitis. TVB-2640, a fatty acid synthase inhibitor, was designed to reduce excess liver fat and directly inhibit inflammatory and fibrogenic pathways. We assessed the safety and efficacy of TVB-2640 in patients with nonalcoholic steatohepatitis in the United States. METHODS: 3V2640-CLIN-005 (FASCINATE-1) was a randomized, placebo-controlled, single-blind study at 10 US sites. Adults with ≥8% liver fat, assessed by magnetic resonance imaging proton density fat fraction, and evidence of liver fibrosis by magnetic resonance elastography ≥2.5 kPa or liver biopsy were eligible. Ninety-nine patients were randomized to receive placebo or 25 mg or 50 mg of TVB-2640 (orally, once-daily for 12 weeks). The primary end points of this study were safety and relative change in liver fat after treatment. RESULTS: Liver fat increased in the placebo cohort by 4.5% relative to baseline; in contrast TVB-2640 reduced liver fat by 9.6% in the 25-mg cohort (n = 30; least squares mean: -15.5%; 95% confidence interval, -31.3 to -0.23; P = .053), and 28.1% in the 50-mg cohort (n = 28; least squares mean: -28.0%; 95% confidence interval, -44.5 to -11.6; P = .001). Eleven percent of patients in the placebo group achieved a ≥30% relative reduction of liver fat compared to 23% in the 25-mg group, and 61% in the 50-mg group (P < .001). Secondary analyses showed improvements of metabolic, pro-inflammatory and fibrotic markers. TVB-2640 was well tolerated; adverse events were mostly mild and balanced among the groups. CONCLUSIONS: TVB-2640 significantly reduced liver fat and improved biochemical, inflammatory, and fibrotic biomarkers after 12 weeks, in a dose-dependent manner in patients with nonalcoholic steatohepatitis. ClinicalTrials.gov, Number NCT03938246.


Subject(s)
Enzyme Inhibitors/therapeutic use , Fatty Acid Synthase, Type I/antagonists & inhibitors , Lipogenesis/drug effects , Liver Cirrhosis/drug therapy , Liver/drug effects , Nitriles/therapeutic use , Non-alcoholic Fatty Liver Disease/drug therapy , Piperidines/therapeutic use , Triazoles/therapeutic use , Adult , Biomarkers/blood , Enzyme Inhibitors/adverse effects , Fatty Acid Synthase, Type I/metabolism , Female , Humans , Lipids/blood , Liver/diagnostic imaging , Liver/enzymology , Liver Cirrhosis/diagnostic imaging , Liver Cirrhosis/enzymology , Male , Middle Aged , Nitriles/adverse effects , Non-alcoholic Fatty Liver Disease/diagnostic imaging , Non-alcoholic Fatty Liver Disease/enzymology , Piperidines/adverse effects , Single-Blind Method , Time Factors , Treatment Outcome , Triazoles/adverse effects , United States
5.
Cell Death Dis ; 12(6): 562, 2021 05 31.
Article in English | MEDLINE | ID: mdl-34059639

ABSTRACT

Ciclopirox (CPX) is an FDA-approved topical antifungal agent that has demonstrated preclinical anticancer activity in a number of solid and hematologic malignancies. Its clinical utility as an oral anticancer agent, however, is limited by poor oral bioavailability and gastrointestinal toxicity. Fosciclopirox, the phosphoryloxymethyl ester of CPX (Ciclopirox Prodrug, CPX-POM), selectively delivers the active metabolite, CPX, to the entire urinary tract following parenteral administration. We characterized the activity of CPX-POM and its major metabolites in in vitro and in vivo preclinical models of high-grade urothelial cancer. CPX inhibited cell proliferation, clonogenicity and spheroid formation, and increased cell cycle arrest at S and G0/G1 phases. Mechanistically, CPX suppressed activation of Notch signaling. Molecular modeling and cellular thermal shift assays demonstrated CPX binding to γ-secretase complex proteins Presenilin 1 and Nicastrin, which are essential for Notch activation. To establish in vivo preclinical proof of principle, we tested fosciclopirox in the validated N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN) mouse bladder cancer model. Once-daily intraperitoneal administration of CPX-POM for four weeks at doses of 235 mg/kg and 470 mg/kg significantly decreased bladder weight, a surrogate for tumor volume, and resulted in a migration to lower stage tumors in CPX-POM treated animals. This was coupled with a reduction in the proliferation index. Additionally, there was a reduction in Presenilin 1 and Hes-1 expression in the bladder tissues of CPX-POM treated animals. Following the completion of the first-in-human Phase 1 trial (NCT03348514), the pharmacologic activity of fosciclopirox is currently being characterized in a Phase 1 expansion cohort study of muscle-invasive bladder cancer patients scheduled for cystectomy (NCT04608045) as well as a Phase 2 trial of newly diagnosed and recurrent urothelial cancer patients scheduled for transurethral resection of bladder tumors (NCT04525131).


Subject(s)
Amyloid Precursor Protein Secretases/metabolism , Antifungal Agents/therapeutic use , Carcinoma, Transitional Cell/drug therapy , Ciclopirox/therapeutic use , Antifungal Agents/pharmacology , Ciclopirox/pharmacology , Humans , Neoplasm Grading
6.
EClinicalMedicine ; 34: 100797, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33870151

ABSTRACT

BACKGROUND: We conducted a first-in-human dose-escalation study with the oral FASN inhibitor TVB-2640 to determine the maximum tolerated dose (MTD) and recommended phase 2 dose (RP2D), as monotherapy and with a taxane. METHODS: This completed open-label outpatient study was conducted at 11 sites in the United States and United Kingdom. Patients with previously-treated advanced metastatic solid tumors and adequate performance status and organ function were eligible. TVB-2640 was administered orally daily until PD. Dose escalation initially followed an accelerated titration design that switched to a standard 3 + 3 design after Grade 2 toxicity occurred. Disease-specific cohorts were enrolled at the MTD. Statistical analyses were primarily descriptive. Safety analyses were performed on patients who received at least 1 dose of study drug. (Clinicaltrials.gov identifier NCT02223247). FINDINGS: The study was conducted from 21 November 2013 to 07 February 2017. Overall, 136 patients received TVB-2640, 76 as monotherapy (weight-based doses of 60 mg/m2 to 240 mg/m2 and flat doses of 200 and 250 mg) and 60 in combination, (weight-based doses of 60 mg/m2 to 100 mg/m2 and flat dose of 200 mg) (55 paclitaxel, 5 docetaxel). DLTs with TVB-2640 were reversible skin and ocular effects. The MTD/RP2D was 100 mg/m2. The most common TEAEs (n,%) with TVB-2640 monotherapy were alopecia (46; 61%), PPE syndrome (35; 46%), fatigue (28; 37%), decreased appetite (20; 26%), and dry skin (17; 22%), and with TVB-2640+paclitaxel were fatigue (29 ; 53%), alopecia (25; 46%), PPE syndrome (25; 46%), nausea (22; 40%), and peripheral neuropathy (20; 36%). One fatal case of drug-related pneumonitis occurred with TVB-2640+paclitaxel; no other treatment-related deaths occurred. Target engagement (FASN inhibition) and inhibition of lipogenesis were demonstrated with TVB-2640. The disease control rate (DCR) with TVB-2640 monotherapy was 42%; no patient treated with monotherapy had a complete or partial response (CR or PR). In combination with paclitaxel, the PR rate was 11% and the DCR was 70%. Responses were seen across multiple tumor types, including in patients with KRASMUT NSCLC, ovarian, and breast cancer. INTERPRETATION: TVB-2640 demonstrated potent FASN inhibition and a predictable and manageable safety profile, primarily characterized by non-serious, reversible adverse events affecting skin and eyes. Further investigation of TVB-2640 in patients with solid tumors, particularly in KRASMUT lung, ovarian, and breast cancer, is warranted. FUNDING: This trial was funded by 3-V Biosciences, Inc. (now known as Sagimet Biosciences Inc.).

7.
Hepatology ; 72(1): 103-118, 2020 07.
Article in English | MEDLINE | ID: mdl-31630414

ABSTRACT

BACKGROUND AND AIMS: Elevated hepatic de novo lipogenesis (DNL) is a key distinguishing characteristic of nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis. In rodent models of NAFLD, treatment with a surrogate of TVB-2640, a pharmacological fatty acid synthase inhibitor, has been shown to reduce hepatic fat and other biomarkers of DNL. The purpose of this phase I clinical study was to test the effect of the TVB-2640 in obese men with certain metabolic abnormalities that put them at risk for NAFLD. APPROACH AND RESULTS: Twelve subjects (mean ± SEM, 42 ± 2 years, body mass index 37.4 ± 1.2 kg/m2 , glucose 103 ± 2 mg/dL, triacylglycerols 196 ± 27 mg/dL, and elevated liver enzymes) underwent 10 days of treatment with TVB-2640 at doses ranging from 50-150 mg/day. Food intake was controlled throughout the study. Hepatic DNL was measured before and after an oral fructose/glucose bolus using isotopic labeling with 1-13 C1 -acetate intravenous infusion, followed by measurement of labeled very low-density lipoprotein palmitate via gas chromatography mass spectometry. Substrate oxidation was measured by indirect calorimetry. Across the range of doses, fasting DNL was reduced by up to 90% (P = 0.003). Increasing plasma concentrations of TVB-2640 were associated with progressive reductions in the percent of fructose-stimulated peak fractional DNL (R2  = -0.749, P = 0.0003) and absolute DNL area under the curve 6 hours following fructose/glucose bolus (R2  = -0.554, P = 0.005). For all subjects combined, alanine aminotransferase was reduced by 15.8 ± 8.4% (P = 0.05). Substrate oxidation was unchanged, and safety monitoring revealed that the drug was well tolerated, without an increase in plasma triglycerides. Alopecia occurred in 2 subjects (reversed after stopping the drug), but otherwise no changes were observed in fasting glucose, insulin, ketones, and renal function. CONCLUSION: These data support the therapeutic potential of a fatty acid synthase inhibitor, TVB-2640 in particular, in patients with NAFLD and nonalcoholic steatohepatitis.


Subject(s)
Enzyme Inhibitors/pharmacology , Fatty Acid Synthases/antagonists & inhibitors , Lipogenesis/drug effects , Liver/metabolism , Metabolic Diseases/metabolism , Nitriles/pharmacology , Piperidines/pharmacology , Triazoles/pharmacology , Adult , Humans , Male
8.
J Pharmacol Exp Ther ; 370(2): 148-159, 2019 08.
Article in English | MEDLINE | ID: mdl-31113837

ABSTRACT

Pharmacokinetic studies in rats and dogs were performed to characterize the in vivo performance of a novel prodrug, fosciclopirox. Ciclopirox olamine (CPX-O) is a marketed topical antifungal agent with demonstrated in vitro and in vivo preclinical anticancer activity in several solid tumor and hematologic malignancies. The oral route of administration for CPX-O is not feasible due to low bioavailability and dose-limiting gastrointestinal toxicities. To enable parenteral administration, the phosphoryl-oxymethyl ester of ciclopirox (CPX), fosciclopirox (CPX-POM), was synthesized and formulated as an injectable drug product. In rats and dogs, intravenous CPX-POM is rapidly and completely metabolized to its active metabolite, CPX. The bioavailability of the active metabolite is complete following CPX-POM administration. CPX and its inactive metabolite, ciclopirox glucuronide (CPX-G), are excreted in urine, resulting in delivery of drug to the entire urinary tract. The absolute bioavailability of CPX following subcutaneous administration of CPX-POM is excellent in rats and dogs, demonstrating the feasibility of this route of administration. These studies confirmed the oral bioavailability of CPX-O is quite low in rats and dogs compared with intravenous CPX-POM. Given its broad-spectrum anticancer activity in several solid tumor and hematologic cancers and renal elimination, CPX-POM is being developed for the treatment of urothelial cancer. The safety, dose tolerance, pharmacokinetics, and pharmacodynamics of intravenous CPX-POM are currently being characterized in a United States multicenter first-in-human Phase 1 clinical trial in patients with advanced solid tumors (NCT03348514).


Subject(s)
Ciclopirox/metabolism , Prodrugs/pharmacology , Prodrugs/pharmacokinetics , Urologic Neoplasms/drug therapy , Urologic Neoplasms/pathology , Urothelium/drug effects , Animals , Biological Availability , Dogs , Male , Prodrugs/metabolism , Prodrugs/therapeutic use , Rats
9.
ACS Appl Mater Interfaces ; 11(3): 2925-2934, 2019 Jan 23.
Article in English | MEDLINE | ID: mdl-30596423

ABSTRACT

K-O2 superoxide batteries have shown great potential for energy-storage applications due to the unique single-electron redox processes in the oxygen or gas-diffusion electrode. Optimization of the 'triple-phase boundary', the region of the cathode where the O2, electrolyte, and electrode surface are in immediate contact, is crucial for maximizing their power performance, but one that has not been explored. Herein, we demonstrate an efficient method for maximizing the power capabilities of the K-O2 battery system by optimizing the interface using polarization and impedance analyses. At the one extreme, an electrolyte volume-deficient state decreases access to the electrochemically active surface area resulting in a limitation of the maximum power output of the K-O2 battery, whereas an excess electrolyte volume state increases the diffusion path to the active surface area for the dissolved O2 inducing mass-transfer limitations sooner, which results in a decrease in the current and power output. Finally, we show that the optimal electrolyte volume closely matches the void volume of the internal cell materials (separators, cathode) resulting in a maximization of the electrochemically accessible surface area while minimizing the O2 diffusion path.

10.
Acc Chem Res ; 51(9): 2335-2343, 2018 09 18.
Article in English | MEDLINE | ID: mdl-30178665

ABSTRACT

Lithium-oxygen (Li-O2) batteries have been envisaged and pursued as the long-term successor to Li-ion batteries, due to the highest theoretical energy density among all known battery chemistries. However, their practical application is hindered by low energy efficiency, sluggish kinetics, and a reliance on catalysts for the oxygen reduction and evolution reactions (ORR/OER). In a superoxide battery, oxygen is also used as the cathodic active medium but is reduced only to superoxide (O2•-), the anion formed by adding an electron to a diatomic oxygen molecule. Therefore, O2/O2•- is a unique single-electron ORR/OER process. Since the introduction of K-O2 batteries by our group in 2013, superoxide batteries based on potassium superoxide (KO2) have attracted increasing interest as promising energy storage devices due to their significantly lower overpotentials and costs. We have selected potassium for building the superoxide battery because it is the lightest alkali metal cation to form the thermodynamically stable superoxide (KO2) product. This allows the battery to operate through the proposed facile one-electron redox process of O2/KO2. This strategy provides an elegant solution to the long-lasting kinetic challenge of ORR/OER in metal-oxygen batteries without using any electrocatalysts. Over the past five years, we have been focused on understanding the electrolyte chemistry, especially at the electrode/electrolyte interphase, and the electrolyte's stability in the presence of potassium metal and superoxide. In this Account, we examine our advances and understanding of the chemistry in superoxide batteries, with an emphasis on our systematic investigation of K-O2 batteries. We first introduce the K metal anode electrochemistry and its corrosion induced by electrolyte decomposition and oxygen crossover. Tuning the electrolyte composition to form a stable solid electrolyte interphase (SEI) is demonstrated to alleviate electrolyte decomposition and O2 cross-talk. We also analyze the nucleation and growth of KO2 in the oxygen electrode, as well its long-term stability. The electrochemical growth of KO2 on the cathode is correlated with the rate performance and capacity. Increasing the surface area and reducing the O2 diffusion pathway are identified as critical strategies to improve the rate performance and capacity. Li-O2 and Na-O2 batteries are further compared with the K-O2 chemistry regarding their pros and cons. Because only KO2 is thermodynamically stable at room temperature, K-O2 batteries offer reversible cathode reactions over the long-term while the counterparts undergo disproportionation. The parasitic reactions due to the reactivity of superoxide are discussed. With the trace side products quantified, the overall superoxide electrochemistry is highly reversible with an extended shelf life. Lastly, potential anode substitutes for K-O2 batteries are reviewed, including the K3Sb alloy and liquid Na-K alloy. We conclude with perspectives on the future development of the K metal anode interface, as well as the electrolyte and cathode materials to enable improved reversibility and maximized power capability. We hope this Account promotes further endeavors into the development of the K-O2 chemistry and related material technologies for superoxide battery research.

11.
Chemistry ; 24(67): 17627-17637, 2018 Dec 03.
Article in English | MEDLINE | ID: mdl-30011356

ABSTRACT

Rechargeable superoxide (O2 - ) batteries have the potential to surpass current lithium-ion technology due to their high theoretical energy densities. The use of superoxides as an energy storage material is highly advantageous when compared to their close relatives, peroxides. This is due to enhanced reversibility of the 1-electron redox process. To efficiently stabilize superoxides, larger metal cations are required such as sodium and potassium. Therefore, the two most studied systems are sodium and potassium-oxygen batteries. Both batteries present unique advantages and challenges. In this minireview, we summarize the current research for each superoxide-based battery and offer perspective for further research.

12.
Leuk Lymphoma ; 59(4): 880-887, 2018 04.
Article in English | MEDLINE | ID: mdl-28853310

ABSTRACT

Cutaneous T-cell lymphomas (CTCL) are a group of non-Hodgkin lymphomas that typically present in the skin but can progress to systemic involvement. The optimal treatment for patients who relapse from or are refractory to systemic chemotherapy remains unclear. Romidepsin is a potent, class-I selective histone deacetylase inhibitor approved for the treatment of patients with CTCL who have had ≥1 prior systemic therapy. Here, we present a subanalysis of two phase-2 trials (NCT00106431, NCT00007345) of romidepsin in patients with CTCL who had prior treatment with systemic chemotherapy. Patients with prior chemotherapy were able to achieve durable responses to romidepsin, and response rates were similar to those in patients who were chemotherapy naïve. Overall, no new safety signals emerged in patients who had received prior chemotherapy. The data presented here suggest that romidepsin is safe and effective in patients with CTCL who received prior systemic chemotherapy.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Depsipeptides/therapeutic use , Histone Deacetylase Inhibitors/therapeutic use , Lymphoma, T-Cell, Cutaneous/drug therapy , Neoplasm Recurrence, Local/drug therapy , Adult , Aged , Clinical Trials, Phase II as Topic , Female , Humans , Lymphoma, T-Cell, Cutaneous/mortality , Lymphoma, T-Cell, Cutaneous/pathology , Male , Middle Aged , Multicenter Studies as Topic , Neoplasm Recurrence, Local/mortality , Neoplasm Recurrence, Local/pathology , Retrospective Studies , Treatment Outcome
13.
J Am Chem Soc ; 139(28): 9475-9478, 2017 07 19.
Article in English | MEDLINE | ID: mdl-28662577

ABSTRACT

Rechargeable potassium metal batteries have recently emerged as alternative energy storage devices beyond lithium-ion batteries. However, potassium metal anodes suffer from poor reversibility during plating and stripping processes due to their high reactivity and unstable solid electrolyte interphase (SEI). Herein, it is reported for the first time that a potassium bis(fluoroslufonyl)imide (KFSI)-dimethoxyethane (DME) electrolyte forms a uniform SEI on the surface of potassium enabling reversible potassium plating/stripping electrochemistry with high efficiency (∼99%) at ambient temperature. Furthermore, the superconcentrated KFSI-DME electrolyte shows excellent electrochemical stability up to 5 V (vs K/K+) which enables good compatibility with high-voltage cathodes. Full cells with potassium Prussian blue cathodes are demonstrated. Our work contributes toward the understanding of potassium plating/stripping electrochemistry and paves the way for the development of potassium metal battery technologies.

14.
Pharmacol Ther ; 177: 23-31, 2017 Sep.
Article in English | MEDLINE | ID: mdl-28202364

ABSTRACT

Decades of preclinical and natural history studies have highlighted the potential of fatty acid synthase (FASN) as a bona fide drug target for oncology. This review will highlight the foundational concepts upon which this perspective is built. Published studies have shown that high levels of FASN in patient tumor tissues are present at later stages of disease and this overexpression predicts poor prognosis. Preclinical studies have shown that experimental overexpression of FASN in previously normal cells leads to changes that are critical for establishing a tumor phenotype. Once the tumor phenotype is established, FASN elicits several changes to the tumor cell and becomes intertwined with its survival. The product of FASN, palmitate, changes the biophysical nature of the tumor cell membrane; membrane microdomains enable the efficient assembly of signaling complexes required for continued tumor cell proliferation and survival. Membranes densely packed with phospholipids containing saturated fatty acids become resistant to the action of other chemotherapeutic agents. Inhibiting FASN leads to tumor cell death while sparing normal cells, which do not have the dependence of this enzyme for normal functions, and restores membrane architecture to more normal properties thereby resensitizing tumors to killing by chemotherapies. One compound has recently reached clinical studies in solid tumor patients and highlights the need for continued evaluation of the role of FASN in tumor cell biology. Significant advances have been made and much remains to be done to optimally apply this class of pharmacological agents for the treatment of specific cancers.


Subject(s)
Fatty Acid Synthases/metabolism , Neoplasms/metabolism , Animals , Antigens, Neoplasm/immunology , Fatty Acid Synthases/antagonists & inhibitors , Fatty Acid Synthases/immunology , Humans , Lipogenesis , Neoplasms/drug therapy , Neoplasms/immunology , Oncogenes , Prognosis
15.
ACS Appl Mater Interfaces ; 9(5): 4301-4308, 2017 Feb 08.
Article in English | MEDLINE | ID: mdl-27408953

ABSTRACT

Owing to the formation of potassium superoxide (K+ + O2 + e- = KO2), K-O2 batteries exhibit superior round-trip efficiency and considerable energy density in the absence of any electrocatalysts. For further improving the practical performance of K-O2 batteries, it is important to carry out a systematic study on parameters that control rate performance and capacity to comprehensively understand the limiting factors in superoxide-based metal-oxygen batteries. Herein, we investigate the influence of current density and oxygen diffusion on the nucleation, growth, and distribution of potassium superoxide (KO2) during the discharge process. It is observed that higher current results in smaller average sizes of KO2 crystals but a larger surface coverage on the carbon fiber electrode. As KO2 grows and covers the cathode surface, the discharge will eventually end due to depletion of the oxygen-approachable electrode surface. Additionally, higher current also induces a greater gradient of oxygen concentration in the porous carbon electrode, resulting in less efficient loading of the discharge product. These two factors explain the observed inverse correlation between current and capacity of K-O2 batteries. Lastly, we demonstrate a reduced graphene oxide-based K-O2 battery with a large specific capacity (up to 8400 mAh/gcarbon at a discharge rate of 1000 mA/gcarbon) and a long cycle life (over 200 cycles).

16.
Angew Chem Int Ed Engl ; 55(49): 15310-15314, 2016 12 05.
Article in English | MEDLINE | ID: mdl-27809386

ABSTRACT

Alkali metal-oxygen batteries are of great interests for energy storage because of their unparalleled theoretical energy densities. Particularly attractive is the emerging Na-O2 battery because of the formation of superoxide as the discharge product. Dimethyl sulfoxide (DMSO) is a promising solvent for this battery but its instability towards Na makes it impractical in the Na-O2 battery. Herein we report the enhanced stability of Na in DMSO solutions containing concentrated sodium trifluoromethanesulfonimide (NaTFSI) salts (>3 mol kg-1 ). Raman spectra of NaTFSI/DMSO electrolytes and ab initio molecular dynamics simulation reveal the Na+ solvation number in DMSO and the formation of Na(DMSO)3 (TFSI)-like solvation structure. The majority of DMSO molecules solvating Na+ in concentrated solutions reduces the available free DMSO molecules that can react with Na and renders the TFSI anion decomposition, which protects Na from reacting with the electrolyte. Using these concentrated electrolytes, Na-O2 batteries can be cycled forming sodium superoxide (NaO2 ) as the sole discharge product with improved long cycle life, highlighting the beneficial role of concentrated electrolytes for Na-based batteries.

17.
ACS Appl Mater Interfaces ; 7(47): 26158-66, 2015 Dec 02.
Article in English | MEDLINE | ID: mdl-26550678

ABSTRACT

Recent investigations into the application of potassium in the form of potassium-oxygen, potassium-sulfur, and potassium-ion batteries represent a new approach to moving beyond current lithium-ion technology. Herein, we report on a high capacity anode material for use in potassium-oxygen and potassium-ion batteries. An antimony-based electrode exhibits a reversible storage capacity of 650 mAh/g (98% of theoretical capacity, 660 mAh/g) corresponding to the formation of a cubic K3Sb alloy. The Sb electrode can cycle for over 50 cycles at a capacity of 250 mAh/g, which is one of the highest reported capacities for a potassium-ion anode material. X-ray diffraction and galvanostatic techniques were used to study the alloy structure and cycling performance, respectively. Cyclic voltammetry and electrochemical impedance spectroscopy were used to provide insight into the thermodynamics and kinetics of the K-Sb alloying reaction. Finally, we explore the application of this anode material in the form of a K3Sb-O2 cell which displays relatively high operating voltages, low overpotentials, increased safety, and interfacial stability, effectively demonstrating its applicability to the field of metal oxygen batteries.

18.
J Am Chem Soc ; 137(26): 8332-5, 2015 Jul 08.
Article in English | MEDLINE | ID: mdl-26102317

ABSTRACT

Integrating both photoelectric-conversion and energy-storage functions into one device allows for the more efficient solar energy usage. Here we demonstrate the concept of an aqueous lithium-iodine (Li-I) solar flow battery (SFB) by incorporation of a built-in dye-sensitized TiO2 photoelectrode in a Li-I redox flow battery via linkage of an I3(-)/I(-) based catholyte, for the simultaneous conversion and storage of solar energy. During the photoassisted charging process, I(-) ions are photoelectrochemically oxidized to I3(-), harvesting solar energy and storing it as chemical energy. The Li-I SFB can be charged at a voltage of 2.90 V under 1 sun AM 1.5 illumination, which is lower than its discharging voltage of 3.30 V. The charging voltage reduction translates to energy savings of close to 20% compared to conventional Li-I batteries. This concept also serves as a guiding design that can be extended to other metal-redox flow battery systems.

19.
Leuk Lymphoma ; 56(10): 2847-54, 2015.
Article in English | MEDLINE | ID: mdl-25791237

ABSTRACT

Cutaneous T-cell lymphoma (CTCL) is a rare heterogeneous group of non-Hodgkin lymphomas that arises in the skin but can progress to systemic disease (lymph nodes, blood, viscera). Historically, in clinical trials of CTCL there has been little consistency in how responses were defined in each disease "compartment"; some studies only assessed responses in the skin. The histone deacetylase inhibitor romidepsin is approved by the US Food and Drug Administration for the treatment of CTCL in patients who have received at least one prior systemic therapy. Phase II studies that led to approval used rigorous composite end points that incorporated disease assessments in all compartments. The objective of this analysis was to thoroughly examine the activity of romidepsin within each disease compartment in patients with CTCL. Romidepsin was shown to have clinical activity across disease compartments and is suitable for use in patients with CTCL having skin involvement only, erythroderma, lymphadenopathy and/or blood involvement.


Subject(s)
Antibiotics, Antineoplastic/therapeutic use , Depsipeptides/therapeutic use , Lymphoma, T-Cell, Cutaneous/drug therapy , Lymphoma, T-Cell, Cutaneous/pathology , Antibiotics, Antineoplastic/pharmacology , Depsipeptides/pharmacology , Female , Humans , Male , Neoplasm Grading , Neoplasm Staging , Retreatment , Treatment Outcome , Tumor Burden
20.
Leuk Lymphoma ; 54(2): 284-9, 2013 Feb.
Article in English | MEDLINE | ID: mdl-22839723

ABSTRACT

Patients with cutaneous T-cell lymphoma (CTCL) frequently experience severe pruritus that can significantly impact their quality of life. Romidepsin is approved by the US Food and Drug Administration (FDA) for the treatment of patients with CTCL who have received at least one prior systemic therapy, with a reported objective response rate of 34%. In a phase 2 study of romidepsin in patients with CTCL (GPI-04-0001), clinically meaningful reduction in pruritus (CMRP) was evaluated as an indicator of clinical benefit by using a patient-assessed visual analog scale. To determine the effect of romidepsin alone, confounding pruritus treatments including steroids and antihistamines were prohibited. At baseline, 76% of patients reported moderate-to-severe pruritus; 43% of these patients experienced CMRP, including 11 who did not achieve an objective response. Median time to CMRP was 1.8 months, and median duration of CMRP was 5.6 months. Study results suggest that the clinical benefit of romidepsin may extend beyond objective responses.


Subject(s)
Antibiotics, Antineoplastic/therapeutic use , Depsipeptides/therapeutic use , Lymphoma, T-Cell, Cutaneous/complications , Lymphoma, T-Cell, Cutaneous/drug therapy , Pruritus/etiology , Aged , Antibiotics, Antineoplastic/administration & dosage , Depsipeptides/administration & dosage , Female , Humans , Lymphoma, T-Cell, Cutaneous/pathology , Male , Middle Aged , Neoplasm Staging , Pruritus/diagnosis , Treatment Outcome
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