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1.
J Mol Biol ; 436(17): 168656, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39237202

RESUMEN

Crosslinking mass spectrometry (MS) has emerged as an important technique for elucidating the in-solution structures of protein complexes and the topology of protein-protein interaction networks. However, the expanding user community lacked an integrated visualisation tool that helped them make use of the crosslinking data for investigating biological mechanisms. We addressed this need by developing xiVIEW, a web-based application designed to streamline crosslinking MS data analysis, which we present here. xiVIEW provides a user-friendly interface for accessing coordinated views of mass spectrometric data, network visualisation, annotations extracted from trusted repositories like UniProtKB, and available 3D structures. In accordance with recent recommendations from the crosslinking MS community, xiVIEW (i) provides a standards compliant parser to improve data integration and (ii) offers accessible visualisation tools. By promoting the adoption of standard file formats and providing a comprehensive visualisation platform, xiVIEW empowers both experimentalists and modellers alike to pursue their respective research interests. We anticipate that xiVIEW will advance crosslinking MS-inspired research, and facilitate broader and more effective investigations into complex biological systems.


Asunto(s)
Reactivos de Enlaces Cruzados , Espectrometría de Masas , Espectrometría de Masas/métodos , Reactivos de Enlaces Cruzados/química , Programas Informáticos , Proteínas/química , Mapeo de Interacción de Proteínas/métodos , Bases de Datos de Proteínas , Interfaz Usuario-Computador , Mapas de Interacción de Proteínas
2.
Artículo en Inglés | MEDLINE | ID: mdl-35162340

RESUMEN

The introduction of carbon fiber plate shoes has triggered a plethora of world records in running, which has encouraged shoe industries to produce novel shoe designs to enhance running performance, including shoes containing conductor elements or "grounding shoes" (GS), which could potentially reduce the energy cost of running. The aim of this study was to examine the physiological and perceptual responses of athletes subjected to grounding shoes during running. Ten elite runners were recruited. Firstly, the athletes performed an incremental running test for VO2max and anaerobic threshold (AT) determination, and were familiarized with the two shoe conditions (traditional training shoe (TTS) and GS, the latter containing a conductor element under the insole). One week apart, athletes performed running economy tests (20 min run at 80% of the AT) on a 400 m dirt track, with shoe conditions randomized. VO2, heart rate, lactate, and perceived fatigue were registered throughout the experiment. No differences in any of the physiological or perceptual variables were identified between shoe conditions, with an equal running economy in both TTS and GS (51.1 ± 4.2 vs. 50.9 ± 5.1 mL kg-1 min-1, respectively). Our results suggest that a grounding stimulus does not improve the energy cost of running, or the physiological/perceptual responses of elite athletes.


Asunto(s)
Carrera , Zapatos , Atletas , Fenómenos Biomecánicos , Humanos , Ácido Láctico , Carrera/fisiología
3.
Preprint en Inglés | medRxiv | ID: ppmedrxiv-21250032

RESUMEN

ObjectivesTo explore the experiences of service users, carers and staff seeking or providing secondary mental health services during the COVID-19 pandemic. DesignQualitative interview study, co-designed with mental health service users and carers. MethodsWe conducted semi-structured, telephone or online interviews with a purposively constructed sample; a peer researcher with lived experience conducted and analysed interviews with service users. Analysis was based on the constant comparison method. SettingNHS secondary mental health services in England between June and August 2020. ParticipantsOf 65 participants, 20 had either accessed or needed to access English secondary mental healthcare during the pandemic; 10 were carers of people with mental health difficulties; 35 were members of staff working in NHS secondary mental health services during the pandemic. ResultsExperiences of remote care were mixed. Some service users valued the convenience of remote methods in the context of maintaining contact with familiar clinicians. Most participants commented that a lack of non-verbal cues and the loss of a therapeutic safe space challenged therapeutic relationship building, assessments, and identification of deteriorating mental wellbeing. Some carers felt excluded from remote meetings and concerned that assessments were incomplete without their input. Like service users, remote methods posed challenges for clinicians who reported uncertainty about technical options and a lack of training. All groups expressed concern about intersectionality exacerbating inequalities and the exclusion of some service user groups if alternatives to remote care are lost. ConclusionsWhilst remote mental healthcare is likely to become increasingly widespread in secondary mental health services, our findings highlight the continued importance of a tailored, personal approach to decisions about remote mental healthcare. Further research should focus on which types of consultations best suit face-to-face interaction, and for whom and why, and which can be provided remotely and by which medium. ARTICLE SUMMARYO_ST_ABSStrengths and limitations of this studyC_ST_ABSO_LIStrengths include its qualitative approach in speaking to a large sample of participants with varied mental health difficulties, carers, and a diverse range of mental healthcare staff. C_LIO_LIIts novelty lies in a deep exploration of the views and experiences of remote mental healthcare during a pandemic. C_LIO_LIThe methods are strengthened by the involvement of experts-by-experience and the use of peer research methods. C_LIO_LIWe did not adopt a narrative method; the interviews were one-off conversations so we could not explore change as the pandemic progressed and people may have become accustomed to remote care. C_LIO_LIThe study used remote methods to comply with UK lockdown regulations; this will have excluded some groups without the ability to engage remotely. C_LI

4.
Science ; 367(6473): 104-108, 2020 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-31896719

RESUMEN

The possible realization of Majorana fermions as quasiparticle excitations in condensed-matter physics has created much excitement. Most studies have focused on Majorana bound states; however, propagating Majorana states with linear dispersion have also been predicted. Here, we report scanning tunneling spectroscopic measurements of crystalline domain walls (DWs) in FeSe0.45Te0.55 We located DWs across which the lattice structure shifts by half a unit cell. These DWs have a finite, flat density of states inside the superconducting gap, which is a hallmark of linearly dispersing modes in one dimension. This signature is absent in DWs in the related superconductor, FeSe, which is not in the topological phase. Our combined data are consistent with the observation of dispersing Majorana states at a π-phase shift DW in a proximitized topological material.

5.
Mol Syst Biol ; 15(9): e8994, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31556486

RESUMEN

We present a concise workflow to enhance the mass spectrometric detection of crosslinked peptides by introducing sequential digestion and the crosslink identification software xiSEARCH. Sequential digestion enhances peptide detection by selective shortening of long tryptic peptides. We demonstrate our simple 12-fraction protocol for crosslinked multi-protein complexes and cell lysates, quantitative analysis, and high-density crosslinking, without requiring specific crosslinker features. This overall approach reveals dynamic protein-protein interaction sites, which are accessible, have fundamental functional relevance and are therefore ideally suited for the development of small molecule inhibitors.


Asunto(s)
Espectrometría de Masas/métodos , Mapeo de Interacción de Proteínas/métodos , Proteínas/química , Proteómica/métodos , Citosol/química , Humanos , Células K562 , Modelos Moleculares , Fragmentos de Péptidos/química , Conformación Proteica , Programas Informáticos
6.
Phys Rev Lett ; 123(1): 017001, 2019 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-31386405

RESUMEN

Recent advances in the development of Josephson scanning tunneling spectroscopy (JSTS) have opened a new path for the exploration of unconventional superconductors. We demonstrate that the critical current I_{c}, measured via JSTS, images the spatial form of the superconducting order parameter in d_{x^{2}-y^{2}}-wave superconductors around defects and in the Fulde-Ferrell-Larkin-Ovchinnikov state. Moreover, we show that I_{c} probes the existence of phase-incoherent superconducting correlations in the pseudogap region of the cuprate superconductors, thus providing unprecedented insight into its elusive nature. These results provide the missing theoretical link between the experimentally measured I_{c} and the spatial structure of the superconducting order parameter.

7.
Opt Express ; 25(16): 18629-18642, 2017 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-29041060

RESUMEN

The collection efficiency of light from a point-like emitter may be extremely poor due to aberrations induced by collection optics and the emission distribution of the source. Analyzing the aberrant wavefront (e.g., with a Shack-Hartmann sensor) and correcting accordingly can be infeasible on the single-photon level. We present a technique that uses a genetic algorithm to control a deformable mirror for correcting wavefront aberrations in single-photon signals from point emitters. We apply our technique to both a simulated point source and a real InAs quantum dot, achieving coupling increases of up to 50% and automatic reduction of system drift.

8.
Head Neck ; 39(12): 2433-2443, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28945296

RESUMEN

BACKGROUND: We examined the prognostic value of a panel of biomarkers in patients with squamous cell carcinoma of the head and neck (SCCHN) who were human immunodeficiency virus (HIV) positive (HIV-positive head and neck cancer) and HIV negative (HIV-negative head and neck cancer). METHODS: Tissue microarrays (TMAs) were constructed using tumors from 41 disease site-matched and age-matched HIV-positive head and neck cancer cases and 44 HIV-negative head and neck cancer controls. Expression of tumor biomarkers was assessed by immunohistochemistry (IHC) and correlations examined with clinical variables. RESULTS: Expression levels of the studied oncogenic and inflammatory tumor biomarkers were not differentially regulated by HIV status. Among patients with HIV-positive head and neck cancer, laryngeal disease site (P = .003) and Clavien-Dindo classification IV (CD4) counts <200 cells/µL (P = .01) were associated with poor prognosis. Multivariate analysis showed that p16 positivity was associated with improved overall survival (OS; P < .001) whereas increased expression of transforming growth factor-beta (TGF-ß) was associated with poor clinical outcome (P = .001). CONCLUSION: Disease site has significant effect on the expression of biomarkers. Expression of tumor TGF-ß could be a valuable addition to the conventional risk stratification equation for improving head and neck cancer disease management strategies.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Carcinoma de Células Escamosas/virología , Seropositividad para VIH/patología , Neoplasias de Cabeza y Cuello/mortalidad , Neoplasias de Cabeza y Cuello/virología , Factor de Crecimiento Transformador beta1/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/mortalidad , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/terapia , Estudios de Casos y Controles , Causas de Muerte , Terapia Combinada , Supervivencia sin Enfermedad , Femenino , Infecciones por VIH/diagnóstico , Infecciones por VIH/epidemiología , Seropositividad para VIH/epidemiología , Neoplasias de Cabeza y Cuello/patología , Neoplasias de Cabeza y Cuello/terapia , Humanos , Estimación de Kaplan-Meier , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Pronóstico , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Medición de Riesgo , Carcinoma de Células Escamosas de Cabeza y Cuello , Análisis de Supervivencia , Resultado del Tratamiento
9.
Head Neck ; 39(5): 840-852, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28236344

RESUMEN

BACKGROUND: Human papillomavirus (HPV)-positive oropharyngeal cancer is generally associated with excellent response to therapy, but some HPV-positive tumors progress despite aggressive therapy. The purpose of this study was to evaluate viral oncogene expression and viral integration sites in HPV16- and HPV18-positive squamous cell carcinoma lines. METHODS: E6/E7 alternate transcripts were assessed by reverse transcriptase-polymerase chain reaction (RT-PCR). Detection of integrated papillomavirus sequences (DIPS-PCR) and sequencing identified viral insertion sites and affected host genes. Cellular gene expression was assessed across viral integration sites. RESULTS: All HPV-positive cell lines expressed alternate HPVE6/E7 splicing indicative of active viral oncogenesis. HPV integration occurred within cancer-related genes TP63, DCC, JAK1, TERT, ATR, ETV6, PGR, PTPRN2, and TMEM237 in 8 head and neck squamous cell carcinoma (HNSCC) lines but UM-SCC-105 and UM-GCC-1 had only intergenic integration. CONCLUSION: HPV integration into cancer-related genes occurred in 7 of 9 HPV-positive cell lines and of these 6 were from tumors that progressed. HPV integration into cancer-related genes may be a secondary carcinogenic driver in HPV-driven tumors. © 2017 Wiley Periodicals, Inc. Head Neck 39: 840-852, 2017.


Asunto(s)
Carcinoma de Células Escamosas/virología , Neoplasias de Cabeza y Cuello/virología , Papillomavirus Humano 16/fisiología , Papillomavirus Humano 18/fisiología , Integración Viral/fisiología , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patología , Técnicas de Cultivo de Célula , Línea Celular Tumoral , Neoplasias de Cabeza y Cuello/genética , Neoplasias de Cabeza y Cuello/patología , Humanos , Proteínas Oncogénicas Virales/metabolismo
10.
Pediatr Res ; 81(3): 504-510, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-27870826

RESUMEN

BACKGROUND: rhIGF-1/rhIGFBP-3 is being investigated for prevention of retinopathy of prematurity in extremely preterm infants. METHODS: A population pharmacokinetic model was developed using data from phase I/II (Sections A-C) trials of rhIGF-1/rhIGFBP-3 and additional studies in preterm infants to predict optimal dosing to establish/maintain serum IGF-1 within physiological intrauterine levels. In Section D of the phase II study, infants (gestational age (GA) (wk+d) 23+0 to 27+6) were randomized to rhIGF-1/rhIGFBP-3, administered at the model-predicted dose of 250 µg/kg/d continuous i.v. infusion up to postmenstrual age (PMA) 29 wk+6 d or standard of care. An interim pharmacokinetic analysis was performed for the first 10 treated infants to verify dosing. RESULTS: Serum IGF-1 data were reviewed for 10 treated/9 control infants. Duration of therapy in treated infants ranged 1-34.5 d. At baseline (before infusion and <24 h from birth), mean (SD) IGF-1 was 19.2 (8.0) µg/l (treated) and 15.4 (4.7) µg/l (controls). Mean (SD) IGF-1 increased to 45.9 (19.6) µg/l at 12 h in treated infants, and remained within target levels for all subsequent timepoints. For treated infants, 88.8% of the IGF-1 measurements were within target levels (controls, 11.1%). CONCLUSION: Through the reported work, we determined appropriate rhIGF-1/rhIGFBP-3 dosing to achieve physiological intrauterine serum IGF-1 levels in extremely preterm infants.


Asunto(s)
Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/sangre , Factor I del Crecimiento Similar a la Insulina/uso terapéutico , Proteínas Recombinantes/sangre , Proteínas Recombinantes/uso terapéutico , Glucemia , Simulación por Computador , Femenino , Edad Gestacional , Humanos , Recien Nacido Extremadamente Prematuro , Recién Nacido , Recien Nacido Prematuro , Masculino , Valores de Referencia , Factores de Tiempo
11.
Genomics ; 108(5-6): 201-208, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27829169

RESUMEN

SLC44A2 was discovered as the target of an antibody that causes hearing loss. Knockout mice develop age related hearing loss, loss of sensory cells and spiral ganglion neurons. SLC44A2 has polymorphic sites implicated in human disease. Transfusion related acute lung injury (TRALI) is linked to rs2288904 and genome wide association studies link rs2288904 and rs9797861 to venous thromboembolism (VTE), coronary artery disease and stroke. Here we report linkage disequilibrium of rs2288904 with rs3087969 and the association of these SLC44A2 SNPs with Meniere's disease severity. Tissue-specific isoform expression differences suggest that the N-terminal domain is linked to different functions in different cell types. Heterozygosity at rs2288904 CGA/CAA and rs3087969 GAT/GAC showed a trend for association with intractable Meniere's disease compared to less severe disease and to controls. The association of SLC44A2 SNPs with VTE suggests that thrombi affecting cochlear vessels could be a factor in Meniere's disease.


Asunto(s)
Glicoproteínas de Membrana/genética , Proteínas de Transporte de Membrana/genética , Enfermedad de Meniere/genética , Polimorfismo de Nucleótido Simple , Adulto , Estudios de Casos y Controles , Células Cultivadas , Oído Interno/metabolismo , Femenino , Heterocigoto , Humanos , Desequilibrio de Ligamiento , Masculino , Glicoproteínas de Membrana/metabolismo , Proteínas de Transporte de Membrana/metabolismo , Enfermedad de Meniere/patología , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo
12.
J Otolaryngol Head Neck Surg ; 45: 26, 2016 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-27117272

RESUMEN

BACKGROUND: Head and neck squamous cell carcinoma (HNSCC) is an aggressive cancer with poor overall survival. New therapeutic strategies that target specific molecular lesions driving advanced disease are needed. Herein we demonstrate the utility of the chicken chorioallantoic membrane (CAM) assay for in vivo human HNSCC tumor growth and metastasis and the tumor suppressive effects of a new chemotherapeutic agent. METHODS: We tested anti-metastatic effects of a WNT pathway inhibitor, WNT974 (also known as LGK974), which targets porcupine (PORCN) the palmityl-transferase that is essential for secretion of Wnt proteins. CAM assays were performed with 8 HNSCC cell lines: UM-SCC-1, UM-SCC-10A, UM-SCC-10B, UM-SCC-11A, UM-SCC-14A UM-SCC-17A, UM-SCC-17B, UM-SCC-25, and UM-SCC-34. RESULTS: UM-SCC-1 (University of Michigan Squamous Cell Carcinoma cell line) CAM xenografts contain CD44+ and ALDH+ cancer stem cell (CSC) proportions similar to UM-SCC-1 mouse xenografts supporting the applicability of the CAM assay for study of CSCs. Inhibition of WNT signaling by the PORCN inhibitor WNT974 reduced metastatic spread of UM-SCC cells, especially in UM-SCCs with Notch1 deficiency. CONCLUSIONS: Our data demonstrate decreased tumor growth and metastases in tumors from cell lines that showed in vitro responses to WNT974, providing evidence that this agent may have a role in future HNSCC therapy.


Asunto(s)
Carcinoma de Células Escamosas/genética , Membrana Corioalantoides/metabolismo , ADN/genética , Neoplasias de Cabeza y Cuello/genética , Mutación , Neoplasias Experimentales , Receptor Notch1/genética , Proteínas Wnt/genética , Animales , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/secundario , Línea Celular Tumoral , Embrión de Pollo , Membrana Corioalantoides/patología , Análisis Mutacional de ADN , Neoplasias de Cabeza y Cuello/metabolismo , Neoplasias de Cabeza y Cuello/secundario , Humanos , Ratones , Metástasis de la Neoplasia , Reacción en Cadena de la Polimerasa , Receptor Notch1/metabolismo , Carcinoma de Células Escamosas de Cabeza y Cuello , Proteínas Wnt/metabolismo , Vía de Señalización Wnt
13.
Head Neck ; 38 Suppl 1: E459-67, 2016 04.
Artículo en Inglés | MEDLINE | ID: mdl-25677579

RESUMEN

BACKGROUND: The purpose of this study was to present the establishment of new cell lines, which is important to cancer research. METHODS: Six new head and neck squamous cell carcinoma cell lines were established using a novel fluorescence-activated cell sorting (FACS) method in order to overcome the barrier of fibroblast overgrowth and the susceptibility of primary tumors to fail in vitro. RESULTS: Antibodies chosen for specific targeting of epithelial cells and fibroblasts successfully separated cells for line establishment in 6 of 12 attempts, providing an alternative method of establishing head and neck squamous cell carcinoma cell lines. Each attempt at cell line establishment resulted in an epithelial carcinoma population, which was genotyped and catalogued as a unique cell line, and a corresponding fibroblast population. CONCLUSION: The selection of antibody markers could be optimized to aid in the establishment of any cancer cell line derived from any tumor tissue; this method is not limited to head and neck cancer. © 2015 Wiley Periodicals, Inc. Head Neck 38: E459-E467, 2016.


Asunto(s)
Carcinoma de Células Escamosas/patología , Línea Celular Tumoral , Citometría de Flujo , Neoplasias de Cabeza y Cuello/patología , Anticuerpos , Técnicas de Cultivo de Célula , Separación Celular , Células Epiteliales , Fibroblastos , Humanos
14.
Mol Cancer Ther ; 14(11): 2569-75, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26333381

RESUMEN

The inhibitor of apoptosis (IAP) family of antiapoptotic proteins has been identified as a target for small molecule inhibitors in cancer. Second mitochondrial-derived activator of caspases (SMAC) efficiently and naturally antagonizes IAPs, and preclinical studies have determined that SMAC mimetics have potent anticancer properties. Here, we report a first-in-human trial designed to determine the maximum tolerated dose (MTD), safety, and pharmacokinetics/pharmacodynamics (PK/PD) of birinapant, a novel SMAC mimetic. Patients with advanced solid tumors or lymphoma were enrolled in a 3+3 dose escalation design with birinapant administered intravenously from 0.18 to 63 mg/m(2) once weekly every 3 of 4 weeks. Fifty patients were enrolled to 12 dose cohorts. Birinapant 47 mg/m(2) was determined to be the MTD. At 63 mg/m(2), dose-limiting toxicities included headache, nausea, and vomiting. Two cases of Bell's palsy (grade 2) also occurred at 63 mg/m(2). Birinapant had a plasma half-life of 30 to 35 hours and accumulated in tumor tissue. Birinapant suppressed cIAP1 and increased apoptosis in peripheral blood mononuclear cells and tumor tissue. Prolonged stable disease was observed in 3 patients: non-small cell lung cancer (5 months), colorectal cancer (5 months), and liposarcoma (9 months). Two patients with colorectal cancer had radiographic evidence of tumor shrinkage. In conclusion, birinapant was well tolerated with an MTD of 47 mg/m(2) and exhibited favorable PK and PD properties. Several patients demonstrated stable disease and evidence of antitumor activity. These results support the ongoing clinical trials of birinapant in patients with cancer.


Asunto(s)
Dipéptidos/uso terapéutico , Indoles/uso terapéutico , Linfoma/tratamiento farmacológico , Neoplasias/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Apoptosis/efectos de los fármacos , Área Bajo la Curva , Western Blotting , Dipéptidos/efectos adversos , Dipéptidos/farmacocinética , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Resistencia a Antineoplásicos , Femenino , Cefalea/inducido químicamente , Humanos , Indoles/efectos adversos , Indoles/farmacocinética , Proteínas Inhibidoras de la Apoptosis/metabolismo , Linfoma/patología , Masculino , Persona de Mediana Edad , Náusea/inducido químicamente , Neoplasias/patología , Resultado del Tratamiento , Vómitos/inducido químicamente
15.
BMC Bioinformatics ; 15: 259, 2014 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-25085009

RESUMEN

BACKGROUND: Plant breeders use an increasingly diverse range of data types to identify lines with desirable characteristics suitable to be taken forward in plant breeding programmes. There are a number of key morphological and physiological traits, such as disease resistance and yield that need to be maintained and improved upon if a commercial variety is to be successful. Computational tools that provide the ability to integrate and visualize this data with pedigree structure, will enable breeders to make better decisions on the lines that are used in crossings to meet both the demands for increased yield/production and adaptation to climate change. RESULTS: We have used a large and unique set of experimental barley (H. vulgare) data to develop a prototype pedigree visualization system. We then used this prototype to perform a subjective user evaluation with domain experts to guide and direct the development of an interactive pedigree visualization tool called Helium. CONCLUSIONS: We show that Helium allows users to easily integrate a number of data types along with large plant pedigrees to offer an integrated environment in which they can explore pedigree data. We have also verified that users were happy with the abstract representation of pedigrees that we have used in our visualization tool.


Asunto(s)
Biología Computacional/métodos , Hordeum/genética , Filogenia , Alelos , Cruzamiento , Conducta Cooperativa , Genotipo , Fenotipo
16.
Ann Otol Rhinol Laryngol ; 123(9): 662-72, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24816422

RESUMEN

OBJECTIVE: A new head and neck cancer cell line was developed from a highly aggressive HNSCC of the oral cavity diagnosed in a 26-year-old pregnant woman. METHODS: Cells from the primary tumor were passaged in culture and genotyped as a unique cell line. The resultant cell line was assessed for its ability to replicate the primary tumor. RESULTS: The primary tumor and cell line contained 19.03% and 19.62% CD44(high) cells, respectively. CD44(high) cancer stem cells from UM-SCC-103 formed tumors after flank injections in mice that reconstituted the heterogeneity of the primary tumor. CD44 staining and histology in the primary tumor and tumors grown in vivo from the cell line were similar. CD44(high) cells from the primary tumor resulted in lung colony formation in 2 out of 2 tail vein injections in mice, whereas CD44(low) cells did not. Similarly, CD44(high) cells from UM-SCC-103 formed lung tumors in 2 out of 4 mice, whereas CD44(low) cells did not. CONCLUSION: The similarity in marker expression and tumorigenic behavior between the primary tumor and the resulting cell line strongly suggests that the cell line resembles the primary tumor that it was derived from and provides an important new research tool for the study of head and neck carcinomas in young patients.


Asunto(s)
Biomarcadores de Tumor/genética , Carcinoma de Células Escamosas/genética , Regulación Neoplásica de la Expresión Génica , Receptores de Hialuranos/genética , Neoplasias de la Lengua/genética , Adulto , Animales , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patología , Línea Celular Tumoral/metabolismo , Femenino , Humanos , Ratones , Células Madre Neoplásicas/metabolismo , Embarazo , Neoplasias de la Lengua/metabolismo , Neoplasias de la Lengua/patología
17.
J Med Chem ; 57(9): 3666-77, 2014 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-24684347

RESUMEN

Birinapant (1) is a second-generation bivalent antagonist of IAP proteins that is currently undergoing clinical development for the treatment of cancer. Using a range of assays that evaluated cIAP1 stability and oligomeric state, we demonstrated that 1 stabilized the cIAP1-BUCR (BIR3-UBA-CARD-RING) dimer and promoted autoubiquitylation of cIAP1 in vitro. Smac-mimetic 1-induced loss of cIAPs correlated with inhibition of TNF-mediated NF-κB activation, caspase activation, and tumor cell killing. Many first-generation Smac-mimetics such as compound A (2) were poorly tolerated. Notably, animals that lack functional cIAP1, cIAP2, and XIAP are not viable, and 2 mimicked features of triple IAP knockout cells in vitro. The improved tolerability of 1 was associated with (i) decreased potency against cIAP2 and affinity for XIAP BIR3 and (ii) decreased ability to inhibit XIAP-dependent signaling pathways. The P2' position of 1 was critical to this differential activity, and this improved tolerability has allowed 1 to proceed into clinical studies.


Asunto(s)
Antineoplásicos/farmacología , Proteínas Portadoras/química , Dipéptidos/farmacología , Neoplasias Hematológicas/tratamiento farmacológico , Indoles/farmacología , Proteínas Mitocondriales/química , Imitación Molecular , Neoplasias Experimentales/tratamiento farmacológico , Animales , Antineoplásicos/uso terapéutico , Proteínas Reguladoras de la Apoptosis , Dipéptidos/uso terapéutico , Descubrimiento de Drogas , Indoles/uso terapéutico , Ratones , Modelos Moleculares
18.
Mol Cancer Ther ; 13(4): 867-79, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24563541

RESUMEN

The acquisition of apoptosis resistance is a fundamental event in cancer development. Among the mechanisms used by cancer cells to evade apoptosis is the dysregulation of inhibitor of apoptosis (IAP) proteins. The activity of the IAPs is regulated by endogenous IAP antagonists such as SMAC (also termed DIABLO). Antagonism of IAP proteins by SMAC occurs via binding of the N-terminal tetrapeptide (AVPI) of SMAC to selected BIR domains of the IAPs. Small molecule compounds that mimic the AVPI motif of SMAC have been designed to overcome IAP-mediated apoptosis resistance of cancer cells. Here, we report the preclinical characterization of birinapant (TL32711), a bivalent SMAC-mimetic compound currently in clinical trials for the treatment of cancer. Birinapant bound to the BIR3 domains of cIAP1, cIAP2, XIAP, and the BIR domain of ML-IAP in vitro and induced the autoubiquitylation and proteasomal degradation of cIAP1 and cIAP2 in intact cells, which resulted in formation of a RIPK1:caspase-8 complex, caspase-8 activation, and induction of tumor cell death. Birinapant preferentially targeted the TRAF2-associated cIAP1 and cIAP2 with subsequent inhibition of TNF-induced NF-κB activation. The activity of a variety of chemotherapeutic cancer drugs was potentiated by birinapant both in a TNF-dependent or TNF-independent manner. Tumor growth in multiple primary patient-derived xenotransplant models was inhibited by birinapant at well-tolerated doses. These results support the therapeutic combination of birinapant with multiple chemotherapies, in particular, those therapies that can induce TNF secretion.


Asunto(s)
Antineoplásicos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Dipéptidos/farmacología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Indoles/farmacología , Animales , Neoplasias de la Mama/patología , Caspasa 8/metabolismo , Línea Celular Tumoral , Sinergismo Farmacológico , Femenino , Humanos , Proteínas Inhibidoras de la Apoptosis/metabolismo , Ratones Desnudos , Proteínas Mitocondriales/metabolismo , Receptores del Factor de Necrosis Tumoral , Transducción de Señal/efectos de los fármacos , Factor 2 Asociado a Receptor de TNF/metabolismo
19.
Proc Natl Acad Sci U S A ; 110(50): 20224-9, 2013 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-24277854

RESUMEN

Wnt signaling is one of the key oncogenic pathways in multiple cancers, and targeting this pathway is an attractive therapeutic approach. However, therapeutic success has been limited because of the lack of therapeutic agents for targets in the Wnt pathway and the lack of a defined patient population that would be sensitive to a Wnt inhibitor. We developed a screen for small molecules that block Wnt secretion. This effort led to the discovery of LGK974, a potent and specific small-molecule Porcupine (PORCN) inhibitor. PORCN is a membrane-bound O-acyltransferase that is required for and dedicated to palmitoylation of Wnt ligands, a necessary step in the processing of Wnt ligand secretion. We show that LGK974 potently inhibits Wnt signaling in vitro and in vivo, including reduction of the Wnt-dependent LRP6 phosphorylation and the expression of Wnt target genes, such as AXIN2. LGK974 is potent and efficacious in multiple tumor models at well-tolerated doses in vivo, including murine and rat mechanistic breast cancer models driven by MMTV-Wnt1 and a human head and neck squamous cell carcinoma model (HN30). We also show that head and neck cancer cell lines with loss-of-function mutations in the Notch signaling pathway have a high response rate to LGK974. Together, these findings provide both a strategy and tools for targeting Wnt-driven cancers through the inhibition of PORCN.


Asunto(s)
Proteínas de la Membrana/antagonistas & inhibidores , Neoplasias/tratamiento farmacológico , Pirazinas/farmacología , Piridinas/farmacología , Vía de Señalización Wnt/efectos de los fármacos , Aciltransferasas , Animales , Proteína Axina/antagonistas & inhibidores , Western Blotting , Línea Celular Tumoral , Clonación Molecular , Ensayos Analíticos de Alto Rendimiento , Humanos , Ratones , Mutagénesis , Fosforilación/efectos de los fármacos , Pirazinas/uso terapéutico , Piridinas/uso terapéutico , Ensayo de Unión Radioligante , Ratas , Receptores Notch/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
20.
JAMA Otolaryngol Head Neck Surg ; 139(12): 1320-7, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24177760

RESUMEN

IMPORTANCE: Human papillomaviruses are now recognized as an etiologic factor in a growing subset of head and neck cancers and have critical prognostic importance that affects therapeutic decision making. There is no universally accepted gold standard for high-risk HPV (hrHPV) assessment in formalin-fixed, paraffin-embedded (FFPE) tissue specimens, nor is there a clear understanding of the frequency or role of hrHPV in sites other than oropharynx. OBJECTIVE: To determine the optimal assessment of hrHPV in FFPE head and neck tumor tissue specimens. DESIGN, SETTING, PARTICIPANTS: In the setting of a large Midwestern referral center, assessment of hrHPV by p16 immunohistochemical staining, in situ hybridization, and polymerase chain reaction (PCR)-MassArray (PCR-MA), with L1 PGMY-PCR and sequencing to resolve method discordance, was conducted for 338 FFPE oropharyngeal, nasopharyngeal, and oral cavity tumor tissue specimens. Relative sensitivity and specificity were compared to develop a standard optimal test protocol. Tissue specimens were collected from 338 patients with head and neck cancer treated during the period 2001 through 2011 in the departments of Otolaryngology, Radiation Oncology, and Medical Oncology. INTERVENTION: Patients received standard therapy. MAIN OUTCOMES AND MEASURES: Optimal hrHPV identification, detection, and activity in head and neck cancers. RESULTS: Using combined PCR-MA with L1 PGMY-PCR and sequencing for conclusive results, we found PCR-MA to have 99.5% sensitivity and 100% specificity, p16 to have 94.2% sensitivity and 85.5% specificity, and in situ hybridization to have 82.9% sensitivity and 81.0% specificity. Among HPV-positive tumors, HPV16 was most frequently detected, but 10 non-HPV16 types accounted for 6% to 50% of tumors, depending on the site. Overall, 86% of oropharynx, 50% of nasopharynx, and 26% of oral cavity tumors were positive for hrHPV. CONCLUSIONS AND RELEVANCE: PCR-MA has a low DNA (5 ng) requirement effective for testing small tissue samples; high throughput; and rapid identification of HPV types, with high sensitivity and specificity. PCR-MA together with p16INK4a provided accurate assessment of HPV presence, type, and activity and was determined to be the best approach for HPV testing in FFPE head and neck tumor tissue specimens.


Asunto(s)
Neoplasias de la Boca/virología , Neoplasias Nasofaríngeas/virología , Neoplasias Orofaríngeas/virología , Papillomaviridae/aislamiento & purificación , Infecciones por Papillomavirus/diagnóstico , Infecciones Tumorales por Virus/diagnóstico , Adulto , Anciano , Biopsia con Aguja , Bases de Datos Factuales , Femenino , Neoplasias de Cabeza y Cuello/patología , Neoplasias de Cabeza y Cuello/virología , Humanos , Hibridación in Situ/métodos , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/patología , Neoplasias Nasofaríngeas/patología , Neoplasias Orofaríngeas/patología , Papillomaviridae/patogenicidad , Adhesión en Parafina , Reacción en Cadena de la Polimerasa/métodos , Estudios Retrospectivos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Medición de Riesgo , Sensibilidad y Especificidad
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