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1.
Chemphyschem ; : e202400235, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38807431

RESUMEN

The cooperative mechanism is of paramount importance in the synthesis of supramolecular polymers with desired characteristics, including molecular mass, polydispersity, and morphology. It is primarily driven by the presence of intermolecular interactions, which encompass strong hydrogen bonding, metal-ligand interactions, and dipole-dipole interactions. In this study, we utilize density functional theory and energy decomposition analysis to investigate the cooperative behavior of perylene diimide (PDI) oligomers with alkyl chains at their imide positions, which lack the previously mentioned interactions. Our systematic examination reveals that dispersion interactions originating from the alkyl side-chain substituents play an important role in promoting cooperativity within these PDIs. This influence becomes even more pronounced for alkyl chain lengths beyond hexyl groups. The energy decomposition analysis reveals that the delicate balance between dispersion energy and Pauli repulsion energy is the key driver of cooperative behavior in PDIs. Additionally, we have developed a mathematical model capable of predicting the saturated binding energies for PDI oligomers of varying sizes and alkyl chain lengths. Overall, our findings emphasize the previously undervalued significance of dispersion forces in cooperative supramolecular polymerization, enhancing our overall understanding of the cooperative mechanism.

2.
Nat Commun ; 15(1): 3672, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38693145

RESUMEN

The synthesis of supramolecular polymers with controlled architecture is a grand challenge in supramolecular chemistry. Although living supramolecular polymerization via primary nucleation has been extensively studied for controlling the supramolecular polymerization of small molecules, the resulting supramolecular polymers have typically exhibited one-dimensional morphology. In this report, we present the synthesis of intriguing supramolecular polymer architectures through a secondary nucleation event, a mechanism well-established in protein aggregation and the crystallization of small molecules. To achieve this, we choose perylene diimide with 2-ethylhexyl chains at the imide position as they are capable of forming dormant monomers in solution. Activating these dormant monomers via mechanical stimuli and hetero-seeding using propoxyethyl perylene diimide seeds, secondary nucleation event takes over, leading to the formation of three-dimensional spherical spherulites and scarf-like supramolecular polymer heterostructures, respectively. Therefore, the results presented in this study propose a simple molecular design for synthesizing well-defined supramolecular polymer architectures via secondary nucleation.

3.
Chemistry ; 30(36): e202303813, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38648278

RESUMEN

Understanding solvent-solute interactions is essential to designing and synthesising soft materials with tailor-made functions. Although the interaction of the solute with the solvent mixture is more complex than the single solvent medium, solvent mixtures are exciting to unfold several unforeseen phenomena in supramolecular chemistry. Here, we report two unforeseen pathways observed during the hierarchical assembly of cationic perylene diimides (cPDIs) in water and amphiphilic organic solvent (AOS) mixtures. When the aqueous supramolecular polymers (SPs) of cPDIs are injected into AOS, initially kinetically trapped short SPs are formed, which gradually transform into thermodynamically stable high aspect ratio SP networks. Using various experimental and theoretical investigations, we found that this temporal evolution follows two distinct pathways depending on the nature of the water-AOS interactions. If the AOS is isopropanol (IPA), water is released from cPDIs into bulk IPA due to strong hydrogen bonding interactions, which further decreases the monomer concentration of cPDIs (Pathway-1). In the case of dioxane AOS, cPDI monomer concentration further increases as water is retained among cPDIs (Pathway-2) due to relatively weak interactions between dioxane and water. Interestingly, these two pathways are accelerated by external stimuli such as heat and mechanical agitation.

4.
Urol Pract ; 11(2): 367-375, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38226931

RESUMEN

INTRODUCTION: In the phase 2/3 study QUILT-3.032 (NCT03022825), the ability of the IL-15RαFc superagonist N-803 (nogapendekin alfa inbakicept) plus bacillus Calmette-Guérin (BCG) to elicit durable complete responses in patients with BCG-unresponsive nonmuscle-invasive bladder cancer (NMIBC) was demonstrated. As a secondary end point, patient-reported outcomes (PROs) were assessed. METHODS: Both cohort A patients with carcinoma in situ with or without Ta/T1 disease and cohort B patients with high-grade Ta/T1 papillary disease who received N-803 plus BCG therapy completed the EORTC (European Organization for Research and Treatment of Cancer) Core 30 and Quality of Life NMIBC-Specific 24 questionnaires at baseline and months 6, 12, 18, and 24 on study. Scores were analyzed using descriptive statistics, and multivariable analyses were performed to identify baseline variables associated with PROs. RESULTS: On study, mean physical function (PF) and global health (GH) scores remained relatively stable from baseline for cohorts A (n = 86) and B (n = 78). At month 6, cohort A patients with a complete response reported higher PF scores than those without (P = .0659); at month 12, > 3 as compared with ≤ 3 prior transurethral resections of bladder tumor was associated (P = .0729) with lower GH scores. In cohort B, baseline disease type was associated (P = .0738) with PF and race was significantly associated (P = .0478) with GH at month 6. NMIBC-Specific 24 summary scores also remained stable on study for both cohorts. CONCLUSIONS: The overall stability of PROs scores, taken together with the efficacy findings, indicates a favorable risk-benefit ratio and quality of life following N-803 plus BCG.


Asunto(s)
Neoplasias Vesicales sin Invasión Muscular , Proteínas Recombinantes de Fusión , Neoplasias de la Vejiga Urinaria , Humanos , Vacuna BCG/uso terapéutico , Calidad de Vida , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico
5.
Phys Chem Chem Phys ; 25(16): 11789-11804, 2023 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-37067357

RESUMEN

There is continuous demand for energy storage devices with high energy densities in consumer electronics, electric vehicles, and the grid energy market. Although commercial lithium-ion batteries (LIBs) satisfy the current needs, the limited availability of their raw materials and the moderate specific charge capacities (SCCs) of LIBS have motivated scientists to search for alternate anode materials for LIBs and create technologies beyond LIBs. In this work, we studied the potential of six cobalt anti-MXenes (CoAs, CoB, CoP, CoS, CoSe, and CoSi), a class of newly discovered 2D materials, as anode materials for lithium, sodium, and potassium ion batteries (LIBs, NIBs, and KIBs). We found that these materials are good electrical conductors and have high adsorption stability for alkali metal ions, which helps to prevent the formation of dendrites and increase the cycle life of the battery. They also show moderate to low migration energy barriers (MEBs), indicating the potential for faster charge-discharge kinetics. We also explain the slightly counter-intuitive result of observing low MEBs along with high adsorption stability. Furthermore, Co-anti-MXenes can adsorb multiple alkali atoms per formula unit, resulting in high specific charge capacities and low average anodic voltages. For example, as anode materials for lithium-ion batteries, CoP and CoSi have SCC values of 1075.4 mA h g-1 and 934 mA h g-1, and anodic voltages as low as 0.28 V and 0.43 V, respectively. Moreover, even the maximally metalated Co-anti-MXenes did not show agglomeration tendency at room temperature. Furthermore, the volume expansion of these materials is minimum for both Li and Na adsorption. As a whole, we find that Co-anti-MXenes are promising as anode materials for alkali metal ion batteries.

6.
J Phys Chem Lett ; 14(11): 2823-2829, 2023 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-36912757

RESUMEN

Restricted migration of reactive species limits chemical transformations within interstellar and cometary ices. We report the migration of CO2 from clathrate hydrate (CH) cages to amorphous solid water (ASW) in the presence of tetrahydrofuran (THF) under ultrahigh vacuum (UHV) and cryogenic conditions. Thermal annealing of sequentially deposited CO2 and H2O ice, CO2@H2O, to 90 K resulted in the partitioning of CO2 in 512 and 51262 CH cages (CO2@512, CO2@51262). However, upon preparing a composite ice film composed of CO2@512, CO2@51262 and THF distributed in the water matrix at 90 K, and annealing the mixture for 6 h at 130 K produced mixed CO2-THF CH, where THF occupied the 51264 cages (THF@51264) exclusively while CO2 in 51262 cages (CO2@51262) got transferred to the ASW matrix and CO2 in the 512 cages (CO2@512) remained as is. This cage-matrix exchange may create a more conducive environment for chemical transformations in interstellar environments.

7.
Phys Chem Chem Phys ; 25(7): 5430-5442, 2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36744506

RESUMEN

A comprehensive understanding of crowding effects on biomolecular processes necessitates investigating the bulk thermodynamic and kinetic properties of the solutions with an accurate molecular representation of the crowded milieu. Recent studies have reparameterized the non-bonded dispersion interaction of solutes to precisely model intermolecular interactions, which would circumvent artificial aggregation as shown by the original force-fields. However, the performance of this reparameterization is yet to be assessed for concentrated crowded solutions in terms of investigating the hydration shell structure, energetics and dynamics. In this study, we perform molecular dynamics simulations of crowded aqueous solutions of five zwitterionic neutral amino acids (Gly, Ala, Thr, Pro, and Ser), mimicking the molecular crowding environment, using a modified AMBER ff99SB-ILDN force-field. We systematically examine and show that the reproducibility of the osmotic coefficients, density, viscosity and self-diffusivity of amino acids improves using the modified force-field in crowded concentrations. The modified force-field also improves the structuring of the solute solvation shells, solute interaction energy and convergence of tails of radial distribution functions, indicating reduction in the artificial aggregation. Our results also indicate that the hydrogen bonding network of water weakens and water molecules anomalously diffuse at small time scales in the crowded solutions. These results underscore the significance of examining the solution properties and anomalous hydration behaviour of water in crowded solutions, which have implications in shaping the structure and dynamics of biomolecules. The findings also illustrate the improvement in predicting bulk solution properties using the modified force-field, thereby providing an approach towards accurate modeling of crowded molecular solutions.


Asunto(s)
Aminoácidos , Simulación de Dinámica Molecular , Aminoácidos/química , Reproducibilidad de los Resultados , Soluciones , Agua/química
8.
Angew Chem Int Ed Engl ; 60(10): 5459-5466, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33247874

RESUMEN

Solvents are fundamentally essential for the synthesis and processing of soft materials. Supramolecular polymers (SPs), an emerging class of soft materials, are usually stable in single and mixtures of poor solvents. In contrast to these preconceived notions, here we report the depolymerization of SPs in the mixture of two poor solvents. This surprising behavior was observed for well-known cationic perylene diimides (cPDIs) in the mixtures of water and amphiphilic organic solvents such as isopropanol (IPA). cPDIs form stable SPs in water and IPA but readily depolymerize into monomers in 50-70 vol% IPA containing water. This is due to the selective solvation of the π-surface of cPDIs by alkyl chains of IPA and ionic side chains by water, as evidenced by molecular dynamic simulations. Moreover, by systematically changing the ratio between water and amphiphilic organic solvent, we could achieve an unprecedented supramolecular polymerization both by increasing and decreasing the solvent polarity.

9.
JCI Insight ; 5(11)2020 06 04.
Artículo en Inglés | MEDLINE | ID: mdl-32493840

RESUMEN

Next-generation sequencing (NGS) has not revealed all the mechanisms underlying resistance to genomically matched drugs. Here, we performed in 1417 tumors whole-exome tumor (somatic)/normal (germline) NGS and whole-transcriptome sequencing, the latter focusing on a clinically oriented 50-gene panel in order to examine transcriptomic silencing of putative driver alterations. In this large-scale study, approximately 13% of the somatic single nucleotide variants (SNVs) were unexpectedly not expressed as RNA; 23% of patients had ≥1 nonexpressed SNV. SNV-bearing genes consistently transcribed were TP53, PIK3CA, and KRAS; those with lower transcription rates were ALK, CSF1R, ERBB4, FLT3, GNAS, HNF1A, KDR, PDGFRA, RET, and SMO. We also determined the frequency of tumor mutations being germline, rather than somatic, in these and an additional 462 tumors with tumor/normal exomes; 33.8% of germline SNVs within the gene panel were rare (not found after filtering through variant information domains) and at risk of being falsely reported as somatic. Both the frequency of silenced variant transcription and the risk of falsely identifying germline mutations as somatic/tumor related are important phenomena. Therefore, transcriptomics is a critical adjunct to genomics when interrogating patient tumors for actionable alterations, because, without expression of the target aberrations, there will likely be therapeutic resistance.


Asunto(s)
Silenciador del Gen , Mutación de Línea Germinal , Neoplasias , Polimorfismo de Nucleótido Simple , Transcriptoma , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/terapia
10.
J Chem Phys ; 150(3): 034701, 2019 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-30660151

RESUMEN

We investigate the structure of water at the interface of three long-chain alcohol monolayers differing in alkyl chain length through molecular dynamics simulations combined with modeling of vibrational sum-frequency generation (vSFG) spectra. The effects of alkyl chain parity on interfacial water are examined through extensive analysis of structural properties, hydrogen bonding motifs, and spectral features. Besides providing molecular-level insights into the structure of interfacial water, this study also demonstrates that, by enabling comparisons with experimental vSFG spectra, computational spectroscopy may be used to test and validate force fields commonly used in biomolecular simulations. The results presented here may serve as benchmarks for further investigations to characterize ice nucleation induced by alcohol monolayers.

11.
Int J Cancer ; 143(11): 3019-3026, 2018 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-29923182

RESUMEN

We sought to compare the tumor profiles of brain metastases from common cancers with those of primary tumors and extracranial metastases in order to identify potential targets and prioritize rational treatment strategies. Tumor samples were collected from both the primary and metastatic sites of nonsmall cell lung cancer, breast cancer and melanoma from patients in locations worldwide, and these were submitted to Caris Life Sciences for tumor multiplatform analysis, including gene sequencing (Sanger and next-generation sequencing with a targeted 47-gene panel), protein expression (assayed by immunohistochemistry) and gene amplification (assayed by in situ hybridization). The data analysis considered differential protein expression, gene amplification and mutations among brain metastases, extracranial metastases and primary tumors. The analyzed population included: 16,999 unmatched primary tumor and/or metastasis samples: 8,178 nonsmall cell lung cancers (5,098 primaries; 2,787 systemic metastases; 293 brain metastases), 7,064 breast cancers (3,496 primaries; 3,469 systemic metastases; 99 brain metastases) and 1,757 melanomas (660 primaries; 996 systemic metastases; 101 brain metastases). TOP2A expression was increased in brain metastases from all 3 cancers, and brain metastases overexpressed multiple proteins clustering around functions critical to DNA synthesis and repair and implicated in chemotherapy resistance, including RRM1, TS, ERCC1 and TOPO1. cMET was overexpressed in melanoma brain metastases relative to primary skin specimens. Brain metastasis patients may particularly benefit from therapeutic targeting of enzymes associated with DNA synthesis, replication and/or repair.


Asunto(s)
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Metástasis de la Neoplasia/genética , Metástasis de la Neoplasia/patología , Anciano , Femenino , Expresión Génica/genética , Humanos , Masculino , Persona de Mediana Edad , Mutación/genética
12.
Anticancer Res ; 38(4): 2235-2240, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29599344

RESUMEN

BACKGROUND/AIM: African Americans (AA) have the highest incidence and mortality of any racial/ethnic group in the US for most cancer types. Heterogeneity in the molecular biology of cancer, as a contributing factor to this disparity, is poorly understood. To address this gap in knowledge, we explored the molecular landscape of colorectal cancer (CRC), non-small cell lung cancer (NSCLC) and high-grade glioma (HGG) from 271 AA and 636 Caucasian (CC) cases. MATERIALS AND METHODS: DNA from formalin-fixed paraffin-embedded tumors was sequenced using next-generation sequencing. Additionally, we evaluated protein expression using immunohistochemistry. The Exome Aggregation Consortium Database was evaluated for known ethnicity associations. RESULTS: Considering only pathogenic or presumed pathogenic mutations, as determined by the American College of Medical Genetics and Genomics guidelines, and using Bonferroni and Benjamini-Hochberg corrections for multiple comparisons, we found that CRC tumors from AA patients harbored significantly more mutations of phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit alpha (PIK3CA) than those from CC patients. CRC tumors in AA patients also appeared to harbor more mutations of mitogen-activated protein kinase kinase 1 (MAP2K1/MEK1), MPL proto-oncogene (MPL), thrombo-poietin receptor, and neurofibromin 1 (NF1) than those from CC patients. In contrast, CRCs from AA patients were likely to carry fewer mutations of ataxia-telangiectasia mutated (ATM), as well as of proto-oncogene B-Raf (BRAF), including the V600E variant, than those from CC patients. Rates of immunohistochemical positivity for epidermal growth factor receptor (EGFR) and DNA topoisomerase 2-alpha (TOP2A) tended to be higher in CRCs from AA patients than in CC patients. In NSCLC adenocarcinoma, BRAF variants appeared to be more frequent in the AA than in the CC cohort, whereas in squamous cell lung carcinoma, programmed death-ligand 1 (PD-L1) expression tended to be lower in the AA than in CC group. Moreover, HGG tumors from AA patients showed a trend toward harboring more mutations of protein tyrosine phosphatase non-receptor 11 (PTPN11), than HGG tumors from the CC cohort. In contrast, mutations of phosphatase and tensin homolog (PTEN) and tumor protein 53 (TP53) appeared to be higher in HGG tumors in CC patients than in their AA counterparts. CONCLUSION: Our data revealed significant differences and trends in molecular signatures of the three cancer types in AA and CC cohorts. These findings imply that there may be differences in carcinogenesis between AA and CC patients and that race may be a factor that should be considered regarding cancer incidence and outcome.


Asunto(s)
Heterogeneidad Genética , Neoplasias/genética , Neoplasias/patología , Grupos Raciales/genética , Negro o Afroamericano/genética , Negro o Afroamericano/estadística & datos numéricos , Anciano , Estudios de Cohortes , Análisis Mutacional de ADN , Femenino , Disparidades en el Estado de Salud , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Masculino , Persona de Mediana Edad , Mutación Missense , Neoplasias/etnología , Proto-Oncogenes Mas , Estados Unidos/epidemiología , Población Blanca/genética , Población Blanca/estadística & datos numéricos
13.
Phys Chem Chem Phys ; 19(16): 10481-10490, 2017 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-28383584

RESUMEN

Sea spray aerosols (SSA) are known to have an organic coating that is mainly composed of fatty acids. In this study, the effect of pH and salt on the stability and organization of a palmitic acid (PA) monolayer is investigated by surface vibrational spectroscopy and molecular dynamics simulations. Results indicate that alkyl chain packing becomes more disordered as the carboxylic headgroup becomes deprotonated. This is associated with packing mismatch of charged and neutral species as charged headgroups penetrate deeper into the solution phase. At pH 10.7, when the monolayer is ∼99% deprotonated, palmitate (PA-) molecules desorb and solubilize into the bulk solution where there is spectroscopic evidence for aggregate formation. Yet, addition of 100 mM NaCl to the bulk solution is found to drive PA- molecules to the aqueous surface. Free energy calculations show that PA- molecules become stabilized within the interface with increasing NaCl concentration. Formation of contact -COO-:Na+ pairs alters the hydration state of PA- headgroups, thus increasing the surface propensity. As salts are highly concentrated in SSA, these results suggest that deprotonated fatty acids may be found at the air-aqueous interface of aerosol particles due to sea salt's role in surface stabilization.

14.
J Chem Theory Comput ; 13(4): 1778-1784, 2017 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-28245359

RESUMEN

Many-body effects in ice are investigated through a systematic analysis of the lattice energies of several proton ordered and disordered phases, which are calculated with different flexible water models, ranging from pairwise additive (q-TIP4P/F) to polarizable (TTM3-F and AMOEBA) and explicit many-body (MB-pol) potential energy functions. Comparisons with available experimental and diffusion Monte Carlo data emphasize the importance of an accurate description of the individual terms of the many-body expansion of the interaction energy between water molecules for the correct prediction of the energy ordering of the ice phases. Further analysis of the MB-pol results, in terms of fundamental energy contributions, demonstrates that the differences in lattice energies between different ice phases are sensitively dependent on the subtle balance between short-range two-body and three-body interactions, many-body induction, and dispersion energy. By correctly reproducing many-body effects at both short range and long range, it is found that MB-pol accurately predicts the energetics of different ice phases, which provides further support for the accuracy of MB-pol in representing the properties of water from the gas to the condensed phase.

15.
J Chem Phys ; 147(24): 244504, 2017 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-29289126

RESUMEN

The structure of liquid water as a function of temperature is investigated through the modeling of infrared and Raman spectra along with structural order parameters calculated from classical and quantum molecular dynamics simulations with the MB-pol many-body potential energy function. The magnitude of nuclear quantum effects is also monitored by comparing the vibrational spectra obtained from classical and centroid molecular dynamics, both in intensities and peak positions. The observed changes in spectral activities are shown to reflect changes in the underlying structure of the hydrogen-bond network and are found to be particularly sensitive to many-body effects in the representation of the electrostatic interactions. Overall, good agreement is found with the experimental spectra, which provides further evidence for the accuracy of MB-pol in predicting the properties of water.

16.
J Chem Phys ; 145(19): 194504, 2016 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-27875875

RESUMEN

The MB-pol many-body potential has recently emerged as an accurate molecular model for water simulations from the gas to the condensed phase. In this study, the accuracy of MB-pol is systematically assessed across the three phases of water through extensive comparisons with experimental data and high-level ab initio calculations. Individual many-body contributions to the interaction energies as well as vibrational spectra of water clusters calculated with MB-pol are in excellent agreement with reference data obtained at the coupled cluster level. Several structural, thermodynamic, and dynamical properties of the liquid phase at atmospheric pressure are investigated through classical molecular dynamics simulations as a function of temperature. The structural properties of the liquid phase are in nearly quantitative agreement with X-ray diffraction data available over the temperature range from 268 to 368 K. The analysis of other thermodynamic and dynamical quantities emphasizes the importance of explicitly including nuclear quantum effects in the simulations, especially at low temperature, for a physically correct description of the properties of liquid water. Furthermore, both densities and lattice energies of several ice phases are also correctly reproduced by MB-pol. Following a recent study of DFT models for water, a score is assigned to each computed property, which demonstrates the high and, in many respects, unprecedented accuracy of MB-pol in representing all three phases of water.

17.
Chemistry ; 22(44): 15864-15873, 2016 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-27611359

RESUMEN

An understanding of solid-state crystal dynamics or flexibility in metal-organic frameworks (MOFs) showing multiple structural changes is highly demanding for the design of materials with potential applications in sensing and recognition. However, entangled MOFs showing such flexible behavior pose a great challenge in terms of extracting information on their dynamics because of their poor single-crystallinity. In this article, detailed experimental studies on a twofold entangled MOF (f-MOF-1) are reported, which unveil its structural response toward external stimuli such as temperature, pressure, and guest molecules. The crystallographic study shows multiple structural changes in f-MOF-1, by which the 3 D net deforms and slides upon guest removal. Two distinct desolvated phases, that is, f-MOF-1 a and f-MOF-1 b, could be isolated; the former is a metastable one and transformable to the latter phase upon heating. The two phases show different gated CO2 adsorption profiles. DFT-based calculations provide an insight into the selective and gated adsorption behavior with CO2 of f-MOF-1 b. The gate-opening threshold pressure of CO2 adsorption can be tuned strategically by changing the chemical functionality of the linker from ethanylene (-CH2 -CH2 -) in f-MOF-1 to an azo (-N=N-) functionality in an analogous MOF, f-MOF-2. The modulation of functionality has an indirect influence on the gate-opening pressure owing to the difference in inter-net interaction. The framework of f-MOF-1 is highly responsive toward CO2 gas molecules, and these results are supported by DFT calculations.

18.
Oncotarget ; 7(43): 69466-69478, 2016 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-27579614

RESUMEN

BACKGROUND: Geriatric glioblastoma (GBM) patients have a poorer prognosis than younger patients, but IDH1/2 mutations (more common in younger patients) confer a favorable prognosis. We compared key GBM molecular alterations between an elderly (age ≥ 70) and younger (18 < = age < = 45) cohort to explore potential therapeutic opportunities. RESULTS: Alterations more prevalent in the young GBM cohort compared to the older cohort (P < 0.05) were: overexpression of ALK, RRM1, TUBB3 and mutation of ATRX, BRAF, IDH1, and TP53. However, PTEN mutation was significantly more frequent in older patients. Among patients with wild-type IDH1/2 status, TOPO1 expression was higher in younger patients, whereas MGMT methylation was more frequent in older patients. Within the molecularly-defined IDH wild-type GBM cohort, younger patients had significantly more mutations in PDGFRA, PTPN11, SMARCA4, BRAF and TP53. METHODS: GBMs from 178 elderly patients and 197 young patients were analyzed using DNA sequencing, immunohistochemistry, in situ hybridization, and MGMT-methylation assay to ascertain mutational and amplification/expressional status. CONCLUSIONS: Significant molecular differences occurred in GBMs from elderly and young patients. Except for the older cohort's more frequent PTEN mutation and MGMT methylation, younger patients had a higher frequency of potential therapeutic targets.


Asunto(s)
Envejecimiento/genética , Biomarcadores de Tumor/genética , Neoplasias Encefálicas/genética , Glioblastoma/genética , Mutación , Adulto , Factores de Edad , Anciano , Biomarcadores de Tumor/metabolismo , Neoplasias Encefálicas/metabolismo , Estudios de Cohortes , Metilación de ADN , Análisis Mutacional de ADN/métodos , Receptores ErbB/genética , Receptores ErbB/metabolismo , Regulación Neoplásica de la Expresión Génica , Glioblastoma/metabolismo , Humanos , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo
19.
Neuro Oncol ; 18(10): 1357-66, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27370400

RESUMEN

BACKGROUND: Expression of programmed cell death protein 1 (PD-1)/programmed death ligand 1 (PD-L1) across glioma grades is undocumented, and their interactions with commonly expressed genetic and epigenetic alterations are undefined but nonetheless highly relevant to combinatorial treatments. METHODS: Patients with CNS malignancies were profiled by Caris Life Sciences from 2009 to 2016. Immunohistochemistry findings for PD-1 on tumor-infiltrating lymphocytes (TIL) and PD-L1 on tumor cells were available for 347 cases. Next-generation sequencing, pyrosequencing, immunohistochemistry, fragment analysis, and fluorescence in situ hybridization were used to determine isocitrate dehydrogenase 1 (IDH1), phosphatase and tensin homolog (PTEN), and tumor protein 53 mutational status, O(6)-DNA methylguanine-methyltransferase promoter methylation (MGMT-Me) status, PTEN expression, plus epidermal growth factor receptor variant III and 1p/19q codeletion status. RESULTS: PD-1+ TIL expression and grade IV gliomas were significantly positively correlated (odds ratio [OR]: 6.363; 95% CI: 1.263, 96.236)-especially in gliosarcomas compared with glioblastoma multiforme (P = .014). PD-L1 expression was significantly correlated with tumor grade with all PD-L1+ cases (n = 21) being associated with grade IV gliomas. PD-1+ TIL expression and PD-L1 expression were significantly correlated (OR: 5.209; 95% CI: 1.555, 20.144). Mutations of PTEN, tumor protein 53, BRAF, IDH1, and epidermal growth factor receptor or MGMT-Me did not associate with increased intratumoral expression of either PD-1+ TIL or PD-L1 in glioblastoma multiforme even before false discovery rate correction for multiple comparison. CONCLUSIONS: Targeting immune checkpoints in combination with other therapeutics based on positive biomarker selection will require screening of large patient cohorts.


Asunto(s)
Antígeno B7-H1/biosíntesis , Biomarcadores de Tumor/análisis , Neoplasias Encefálicas/metabolismo , Glioma/metabolismo , Receptor de Muerte Celular Programada 1/biosíntesis , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antígeno B7-H1/análisis , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Niño , Preescolar , Femenino , Glioma/genética , Glioma/patología , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Inmunohistoquímica , Hibridación Fluorescente in Situ , Linfocitos Infiltrantes de Tumor/metabolismo , Linfocitos Infiltrantes de Tumor/patología , Masculino , Persona de Mediana Edad , Mutación , Receptor de Muerte Celular Programada 1/análisis , Adulto Joven
20.
J Surg Oncol ; 113(1): 55-61, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26661118

RESUMEN

BACKGROUND AND OBJECTIVES: Effective therapies for hepatocellular carcinoma (HCC) are limited. Molecular profiling of HCC was performed to identify novel therapeutic targets. METHODS: 350 HCC samples were evaluated using a multiplatform profiling service (Caris Life Sciences, Phoenix, AZ), including gene sequencing, amplification, and protein expression. RESULTS: EGFR, TOPO1, PD-1, TOP2A, SPARC, and c-Met were overexpressed in 25-83% of samples. Decreased expression of RRM1,TS, PTEN, and MGMT occurred in 31-82% of samples. TP53 was mutated in 30%, CTNNB1 in 20%, and BRCA2 in 18%; other gene mutation rates were <5%. TP53-mutated tumors showed significantly higher TOPO2A (90% vs. 38%, P < 0.0001) and TS (56% vs. 29%, P = 0.0139) expression. CTNNB1-mutated tumors had significantly higher AR (56% vs. 21%, P = 0.0017), SPARC (61% vs. 29%, P = 0.0135), PDL1 (29% vs. 0%, P = 0.0256) expression, and BRCA2 mutations (50% vs. 6%, P = 0.0458). Metastases exhibited significantly higher infiltration by PD-1+ lymphocytes (79% vs. 50%, P = 0.047) and TS (31% vs. 14%, P < 0.0003) than primary HCC. CONCLUSIONS: Multiplatform profiling reveals molecular heterogeneity in HCC and identifies potential therapies including tyrosine kinase, PI3 kinase, or PARP inhibitors for molecular subtypes. Chemotherapy may benefit some tumors. CTNNB1-mutated tumors may respond to multi-target inhibition. These limited and preliminary data require clinical validation.


Asunto(s)
Antineoplásicos/farmacología , Biomarcadores de Tumor/análisis , Carcinoma Hepatocelular/química , Perfilación de la Expresión Génica , Neoplasias Hepáticas/química , Terapia Molecular Dirigida , Mutación , Inhibidores de las Quinasa Fosfoinosítidos-3 , Proteínas Tirosina Quinasas/antagonistas & inhibidores , beta Catenina/genética , Adulto , Anciano , Anciano de 80 o más Años , Antineoplásicos/uso terapéutico , Carcinoma Hepatocelular/tratamiento farmacológico , Clorhidrato de Erlotinib/administración & dosificación , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Inmunohistoquímica , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Pulmonares/secundario , Neoplasias Pulmonares/terapia , Masculino , Persona de Mediana Edad , Niacinamida/administración & dosificación , Niacinamida/análogos & derivados , Compuestos de Fenilurea/administración & dosificación , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacología , Estudios Retrospectivos , Sorafenib , Proteína p53 Supresora de Tumor/genética
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