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1.
Proc Natl Acad Sci U S A ; 120(16): e2218280120, 2023 04 18.
Artículo en Inglés | MEDLINE | ID: mdl-37036992

RESUMEN

Migratory insects are key players in ecosystem functioning and services, but their spatiotemporal distributions are typically poorly known. Ecological niche modeling (ENM) may be used to predict species seasonal distributions, but the resulting hypotheses should eventually be validated by field data. The painted lady butterfly (Vanessa cardui) performs multigenerational migrations between Europe and Africa and has become a model species for insect movement ecology. While the annual migration cycle of this species is well understood for Europe and northernmost Africa, it is still unknown where most individuals spend the winter. Through ENM, we previously predicted suitable breeding grounds in the subhumid regions near the tropics between November and February. In this work, we assess the suitability of these predictions through i) extensive field surveys and ii) two-year monitoring in six countries: a large-scale monitoring scheme to study butterfly migration in Africa. We document new breeding locations, year-round phenological information, and hostplant use. Field observations were nearly always predicted with high probability by the previous ENM, and monitoring demonstrated the influence of the precipitation seasonality regime on migratory phenology. Using the updated dataset, we built a refined ENM for the Palearctic-African range of V. cardui. We confirm the relevance of the Afrotropical region and document the missing natural history pieces of the longest migratory cycle described in butterflies.


Asunto(s)
Mariposas Diurnas , Humanos , Animales , Ecosistema , Migración Animal , Europa (Continente) , Insectos , Estaciones del Año
2.
Rapid Commun Mass Spectrom ; 38(3): e9675, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38211347

RESUMEN

RATIONALE: Many insect species undertake multigenerational migrations in the Afro-tropical and Palearctic ranges, and understanding their migratory connectivity remains challenging due to their small size, short life span and large population sizes. Hydrogen isotopes (δ2 H) can be used to reconstruct the movement of dispersing or migrating insects, but applying δ2 H for provenance requires a robust isotope baseline map (i.e. isoscape) for the Afro-Palearctic. METHODS: We analyzed the δ2 H in the wings (δ2 Hwing ) of 142 resident butterflies from 56 sites across the Afro-Palearctic. The δ2 Hwing values were compared to the predicted local growing-season precipitation δ2 H values (δ2 HGSP ) using a linear regression model to develop an insect wing δ2 H isoscape. We used multivariate linear mixed models and high-resolution and time-specific remote sensing climate and environmental data to explore the controls of the residual δ2 Hwing variability. RESULTS: A strong linear relationship was found between δ2 Hwing and δ2 HGSP values (r2 = 0.53). The resulting isoscape showed strong patterns across the Palearctic but limited variation and high uncertainty for the Afro-tropics. Positive residuals of this relationship were correlated with dry conditions for the month preceding sampling whereas negative residuals were correlated with more wet days for the month preceding sampling. High intra-site δ2 Hwing variance was associated with lower relative humidity for the month preceding sampling and higher elevation. CONCLUSION: The δ2 Hwing isoscape is applicable for tracing herbivorous lepidopteran insects that migrate across the Afro-Palearctic range but has limited geolocation potential in the Afro-tropics. The spatial analysis of uncertainty using high-resolution climatic data demonstrated that many African regions with highly variable evaporation rates and relative humidity have δ2 Hwing values that are less related to δ2 HGSP values. Increasing geolocation precision will require new modeling approaches using more time-specific environmental data and/or independent geolocation tools.


Asunto(s)
Mariposas Diurnas , Animales , Hidrógeno , Isótopos/análisis , Estaciones del Año , Modelos Lineales
3.
Rev Med Suisse ; 19(847): 1994-2001, 2023 Oct 25.
Artículo en Francés | MEDLINE | ID: mdl-37878099

RESUMEN

Gout is a common complication occurring among inpatients, as factors affecting urate levels in blood and tissues are often modified by acute conditions. The control of chronic uricemia within recommended target values helps reduce the risk of flares. Joint aspiration is the gold standard for diagnosis, but ultrasound and dual-energy CT scan are reasonable alternatives. Acute and chronic treatments do not differ from those provided in outpatient care, although the increased prevalence of organ failures often require treatment adjustments. Active patient engagement, including therapeutic education during hospitalization, is essential for long-term disease control.


Lors d'un séjour hospitalier, les facteurs impactant la concentration sanguine et tissulaire d'urate sont souvent modifiés, augmentant le risque d'une crise de goutte. Le maintien de l'uricémie dans les cibles reconnues grâce à la poursuite des traitements contribue à réduire ce risque. La ponction articulaire est la méthode de référence pour établir le diagnostic, mais l'ultrason et le scanner à double énergie sont des alternatives fiables pour diagnostiquer une goutte. Les traitements aigu et chronique ne diffèrent pas de ceux pratiqués en ambulatoire, mais la fréquence augmentée d'insuffisances d'organes peut nécessiter l'adaptation des traitements. Pour assurer un contrôle de la maladie sur le long terme, il est essentiel d'impliquer le patient dans sa prise en charge, notamment par l'éducation thérapeutique dispensée pendant l'hospitalisation.


Asunto(s)
Gota , Pacientes Internos , Humanos , Gota/diagnóstico , Gota/terapia , Atención Ambulatoria , Hospitalización , Participación del Paciente
4.
Proc Natl Acad Sci U S A ; 115(41): 10345-10350, 2018 10 09.
Artículo en Inglés | MEDLINE | ID: mdl-30254171

RESUMEN

The structure of the actin filament is known at a resolution that has allowed the architecture of protein components to be unambiguously assigned. However, fully understanding the chemistry of the system requires higher resolution to identify the ions and water molecules involved in polymerization and ATP hydrolysis. Here, we find experimental evidence for the association of cations with the surfaces of G-actin in a 2.0-Šresolution X-ray structure of actin bound to a Cordon-Bleu WH2 motif and in previously determined high-resolution X-ray structures. Three of four reoccurring divalent cation sites were stable during molecular dynamics (MD) simulations of the filament, suggesting that these sites may play a functional role in stabilizing the filament. We modeled the water coordination at the ATP-bound Mg2+, which also proved to be stable during the MD simulations. Using this model of the filament with a hydrated ATP-bound Mg2+, we compared the cumulative probability of an activated hydrolytic water molecule approaching the γ-phosphorous of ATP, in comparison with G-actin, in the MD simulations. The cumulative probability increased in F-actin in line with the activation of actin's ATPase activity on polymerization. However, inclusion of the cations in the filament lowered cumulative probability, suggesting the rate of hydrolysis may be linked to filament flexibility. Together, these data extend the possible roles of Mg2+ in polymerization and the mechanism of polymerization-induced activation of actin's ATPase activity.


Asunto(s)
Actinas/química , Actinas/metabolismo , Adenosina Trifosfato/metabolismo , Cationes Bivalentes/metabolismo , Animales , Cristalografía por Rayos X , Proteínas del Citoesqueleto , Hidrólisis , Magnesio/química , Magnesio/metabolismo , Proteínas de Microfilamentos , Modelos Moleculares , Simulación de Dinámica Molecular , Proteínas/química , Proteínas/metabolismo , Conejos , Agua/química
5.
Ann Oncol ; 31(7): 942-950, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32294530

RESUMEN

BACKGROUND: Targeting the programmed cell death protein 1 (PD-1)/programmed cell death ligand 1 (PD-L1) axis has demonstrated clinical benefit in recurrent/metastatic head and neck squamous cell carcinoma (R/M HNSCC). Combining immunotherapies targeting PD-L1 and cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) has shown evidence of additive activity in several tumor types. This phase III study evaluated the efficacy of durvalumab (an anti-PD-L1 monoclonal antibody) or durvalumab plus tremelimumab (an anti-CTLA-4 monoclonal antibody) versus standard of care (SoC) in R/M HNSCC patients. PATIENTS AND METHODS: Patients were randomly assigned to receive 1 : 1 : 1 durvalumab (10 mg/kg every 2 weeks [q2w]), durvalumab plus tremelimumab (durvalumab 20 mg/kg q4w plus tremelimumab 1 mg/kg q4w × 4, then durvalumab 10 mg/kg q2w), or SoC (cetuximab, a taxane, methotrexate, or a fluoropyrimidine). The primary end points were overall survival (OS) for durvalumab versus SoC, and OS for durvalumab plus tremelimumab versus SoC. Secondary end points included progression-free survival (PFS), objective response rate, and duration of response. RESULTS: Patients were randomly assigned to receive durvalumab (n = 240), durvalumab plus tremelimumab (n = 247), or SoC (n = 249). No statistically significant improvements in OS were observed for durvalumab versus SoC [hazard ratio (HR): 0.88; 95% confidence interval (CI): 0.72-1.08; P = 0.20] or durvalumab plus tremelimumab versus SoC (HR: 1.04; 95% CI: 0.85-1.26; P = 0.76). The 12-month survival rates (95% CI) were 37.0% (30.9-43.1), 30.4% (24.7-36.3), and 30.5% (24.7-36.4) for durvalumab, durvalumab plus tremelimumab, and SoC, respectively. Treatment-related adverse events (trAEs) were consistent with previous reports. The most common trAEs (any grade) were hypothyroidism for durvalumab and durvalumab plus tremelimumab (11.4% and 12.2%, respectively), and anemia (17.5%) for SoC. Grade ≥3 trAE rates were 10.1%, 16.3%, and 24.2% for durvalumab, durvalumab plus tremelimumab, and SoC, respectively. CONCLUSION: There were no statistically significant differences in OS for durvalumab or durvalumab plus tremelimumab versus SoC. However, higher survival rates at 12 to 24 months and response rates demonstrate clinical activity for durvalumab. TRIAL REGISTRATION: ClinicalTrials.gov: NCT02369874.


Asunto(s)
Anticuerpos Monoclonales Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias de Cabeza y Cuello , Anticuerpos Monoclonales , Anticuerpos Monoclonales Humanizados/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Humanos , Recurrencia Local de Neoplasia/tratamiento farmacológico , Carcinoma de Células Escamosas de Cabeza y Cuello/tratamiento farmacológico
6.
Bioessays ; 40(4): e1700213, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29484695

RESUMEN

Structural biology has experienced several transformative technological advances in recent years. These include: development of extremely bright X-ray sources (microfocus synchrotron beamlines and free electron lasers) and the use of electrons to extend protein crystallography to ever decreasing crystal sizes; and an increase in the resolution attainable by cryo-electron microscopy. Here we discuss the use of these techniques in general terms and highlight their application for biological filament systems, an area that is severely underrepresented in atomic resolution structures. We assemble a model of a capped tropomyosin-actin minifilament to demonstrate the utility of combining structures determined by different techniques. Finally, we survey the methods that attempt to transform high resolution structural biology into more physiological environments, such as the cell. Together these techniques promise a compelling decade for structural biology and, more importantly, they will provide exciting discoveries in understanding the designs and purposes of biological machines.


Asunto(s)
Actinas/ultraestructura , Citoesqueleto de Actina/ultraestructura , Proteína CapZ/ultraestructura , Microscopía por Crioelectrón , Tropomodulina/ultraestructura
8.
Rapid Commun Mass Spectrom ; 33(5): 461-472, 2019 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-30597678

RESUMEN

RATIONALE: Strontium isotope ratios (87 Sr/86 Sr) of hair may be a valuable tool to estimate human provenance. However, the systematics and mechanisms controlling spatial variation in 87 Sr/86 Sr of modern human hair remain unclear. Here, we measure 87 Sr/86 Sr of hair specimens from across the USA to assess the presence of geospatial relationships. METHODS: Ninety-eight human hair specimens were collected from salon/barbershop floors in 48 municipalities throughout the conterminous USA. [Sr] and 87 Sr/86 Sr ratios were measured from hair using quadrupole and multi-collector inductively coupled plasma mass spectrometers, respectively. The [Sr] and 87 Sr/86 Sr ratios of hair were compared with the measured [Sr] and 87 Sr/86 Sr ratios of tap waters from the collection locations. In addition, the 87 Sr/86 Sr ratio of hair was compared with the modeled ratios of bedrock and surface waters. RESULTS: Hair color was independent of the 87 Sr/86 Sr ratio, but related to [Sr]. The 87 Sr/86 Sr ratios of hair and leachate were not statistically different and were positively correlated; however, in several hair-leachate pairs, the ratios were conspicuously different. The 87 Sr/86 Sr ratios of both hair and leachate were linearly correlated with tap water. The 87 Sr/86 Sr ratio of hair was also significantly correlated with the modeled ratio of bedrock and surface waters, although the 87 Sr/86 Sr ratio of hair was most strongly correlated with the measured ratio of tap water. CONCLUSIONS: The 87 Sr/86 Sr ratio of hair is related to the ratio of tap water, which varied geographically. The ratio of hair provided geographic information about an individual's recent residence. Differences in the 87 Sr/86 Sr ratios of hair and hair leachate may be concomitant with travel and could potentially be used as a screening tool to identify recent movements.


Asunto(s)
Agua Potable/análisis , Cabello/química , Isótopos de Estroncio/análisis , Agua Dulce/química , Humanos , Espectrometría de Masas , Estados Unidos
9.
Ann Oncol ; 29(4): 985-991, 2018 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-29346507

RESUMEN

Background: To investigate the activity and safety of afatinib in the preoperative treatment of squamous cell carcinoma of the head and neck (SCCHN). Patients and methods: This study was an open-label, randomized, multicenter, phase II window of opportunity trial. Treatment-naïve SCCHN patients selected for primary curative surgery were randomized (5 : 1 ratio) to receive afatinib during 14 days (day -15 until day -1) before surgery (day 0) or no treatment. Tumor biopsies, 2-[fluorine-18]-fluoro-2-deoxy-d-glucose positron emission tomography (FDG-PET), and magnetic resonance imaging (MRI) were carried out at diagnosis and just before surgery. The primary end point was metabolic FDG-PET response (according to EORTC guidelines). Other end points included response assessment based on the Response Evaluation Criteria In Solid Tumors (RECIST) v1.1, dynamic contrast-enhanced (DCE)-MRI, diffusion weighted (DW)-MRI, safety, and translational research (TR). Results: Thirty patients were randomized: 25 to afatinib and 5 to control arm. Of the 23 eligible patients randomized to afatinib, 16 (70%; 95% CI: 47% to 87%) patients had a partial metabolic FDG-PET response (PMR). Five patients (22%; 95% CI: 8% to 44%) showed a partial response by RECISTv1.1. Responses assessed via DCE-MRI and DWI-MRI did not show a strong association with PMR or RECIST. One patient discontinued afatinib after 11 days for grade 3 diarrhea with subsequent renal failure and 24 days delay in surgery. No grade 4 toxicities or surgical comorbidities related to afatinib were reported. TR results indicated that PMR was more frequent in the tumors with high Cluster3-hypoxia score expression and with TP53 wild type. Conclusion: Afatinib given for 2 weeks to newly diagnosed SCCHN patients induces a high rate of FDG-PET partial metabolic response and partial response according to RECISTv1.1. Afatinib can be safely administered before surgery. Although exploratory, the hypoxic gene signature needs further investigations as a predictive biomarker of afatinib activity. Clinical trial registration: ClinicalTrials.gov: NCT01538381.


Asunto(s)
Afatinib/uso terapéutico , Antineoplásicos/uso terapéutico , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Carcinoma de Células Escamosas de Cabeza y Cuello/tratamiento farmacológico , Adulto , Afatinib/efectos adversos , Anciano , Antineoplásicos/efectos adversos , Biomarcadores/metabolismo , Femenino , Fluorodesoxiglucosa F18/administración & dosificación , Neoplasias de Cabeza y Cuello/diagnóstico por imagen , Neoplasias de Cabeza y Cuello/metabolismo , Neoplasias de Cabeza y Cuello/cirugía , Humanos , Masculino , Persona de Mediana Edad , Tomografía de Emisión de Positrones , Cuidados Preoperatorios , Carcinoma de Células Escamosas de Cabeza y Cuello/diagnóstico por imagen , Carcinoma de Células Escamosas de Cabeza y Cuello/metabolismo , Carcinoma de Células Escamosas de Cabeza y Cuello/cirugía
10.
J Transl Med ; 16(1): 142, 2018 05 29.
Artículo en Inglés | MEDLINE | ID: mdl-29843811

RESUMEN

BACKGROUND: Standard therapy for glioblastoma includes surgery, radiotherapy, and temozolomide. This Phase 3 trial evaluates the addition of an autologous tumor lysate-pulsed dendritic cell vaccine (DCVax®-L) to standard therapy for newly diagnosed glioblastoma. METHODS: After surgery and chemoradiotherapy, patients were randomized (2:1) to receive temozolomide plus DCVax-L (n = 232) or temozolomide and placebo (n = 99). Following recurrence, all patients were allowed to receive DCVax-L, without unblinding. The primary endpoint was progression free survival (PFS); the secondary endpoint was overall survival (OS). RESULTS: For the intent-to-treat (ITT) population (n = 331), median OS (mOS) was 23.1 months from surgery. Because of the cross-over trial design, nearly 90% of the ITT population received DCVax-L. For patients with methylated MGMT (n = 131), mOS was 34.7 months from surgery, with a 3-year survival of 46.4%. As of this analysis, 223 patients are ≥ 30 months past their surgery date; 67 of these (30.0%) have lived ≥ 30 months and have a Kaplan-Meier (KM)-derived mOS of 46.5 months. 182 patients are ≥ 36 months past surgery; 44 of these (24.2%) have lived ≥ 36 months and have a KM-derived mOS of 88.2 months. A population of extended survivors (n = 100) with mOS of 40.5 months, not explained by known prognostic factors, will be analyzed further. Only 2.1% of ITT patients (n = 7) had a grade 3 or 4 adverse event that was deemed at least possibly related to the vaccine. Overall adverse events with DCVax were comparable to standard therapy alone. CONCLUSIONS: Addition of DCVax-L to standard therapy is feasible and safe in glioblastoma patients, and may extend survival. Trial registration Funded by Northwest Biotherapeutics; Clinicaltrials.gov number: NCT00045968; https://clinicaltrials.gov/ct2/show/NCT00045968?term=NCT00045968&rank=1 ; initially registered 19 September 2002.


Asunto(s)
Neoplasias Encefálicas/inmunología , Neoplasias Encefálicas/terapia , Vacunas contra el Cáncer/inmunología , Células Dendríticas/inmunología , Glioblastoma/inmunología , Glioblastoma/terapia , Adulto , Anciano , Neoplasias Encefálicas/diagnóstico , Vacunas contra el Cáncer/efectos adversos , Determinación de Punto Final , Femenino , Glioblastoma/diagnóstico , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Análisis de Supervivencia , Resultado del Tratamiento , Adulto Joven
11.
J Transl Med ; 16(1): 179, 2018 06 29.
Artículo en Inglés | MEDLINE | ID: mdl-29958537

RESUMEN

Following publication of the original article [1], the authors reported an error in the spelling of one of the author names. In this Correction the incorrect and correct author names are indicated and the author name has been updated in the original publication. The authors also reported an error in the Methods section of the original article. In this Correction the incorrect and correct versions of the affected sentence are indicated. The original article has not been updated with regards to the error in the Methods section.

12.
Support Care Cancer ; 26(3): 869-878, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28963584

RESUMEN

BACKGROUND: Several case reports and small case series have suggested a higher incidence of medication-related osteonecrosis of the jaw (MRONJ) in patients treated concomitantly with bone resorption inhibitors (BRIs) and vascular endothelial growth factor receptor tyrosine kinase inhibitors (VEGFR-TKIs), as compared to patients treated with BRIs alone. We aimed to assess ONJ-incidence in patients exposed concomitantly to BRIs and VEGFR-TKIs. PATIENTS AND METHODS: We reviewed the records of all patients who received VEGFR-TKIs concomitantly with BRIs. Patients, who were treated with BRIs without VEGFR-TKI, served as a control group. Endpoints of the study were total MRONJ-incidence, MRONJ-incidence during the first and second year of exposure, and time-to-ONJ-incidence. RESULTS: Ninety patients were treated concomitantly with BRIs and VEGFR-TKIs with a median BRI-exposure of 5.0 months. Total MRONJ-incidence was 11.1%. During the first year of BRI-exposure (with a median concomitant exposure of 4.0 months), 6 out of 90 patients (6.7%) developed a MRONJ, compared to 1.1% in the control group (odds ratio 5.9; 95%CI 2.0-18.0; p = 0.0035). In Kaplan-Meier estimates, time-to-ONJ-incidence was significantly shorter in patients treated with BRIs and VEGFR-TKIs compared to BRIs alone (hazard ratio 9.5; 95%CI 3.1-29.6; p < 0.0001). MRONJs occurred earlier in patients treated concomitantly compared to patients treated with BRIs only (after a median exposure of 4.5 and 25.0 months, respectively; p = 0.0033). CONCLUSION: With a global MRONJ-incidence of 11%, patients receiving concomitant treatment with VEGFR-TKIs and BRIs have a five to ten times higher risk for development of MRONJ compared to patients treated with BRIs alone.


Asunto(s)
Osteonecrosis de los Maxilares Asociada a Difosfonatos/tratamiento farmacológico , Conservadores de la Densidad Ósea/efectos adversos , Inhibidores de Proteínas Quinasas/efectos adversos , Factor A de Crecimiento Endotelial Vascular/efectos adversos , Adulto , Anciano , Anciano de 80 o más Años , Osteonecrosis de los Maxilares Asociada a Difosfonatos/patología , Conservadores de la Densidad Ósea/farmacología , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Inhibidores de Proteínas Quinasas/farmacología , Factor A de Crecimiento Endotelial Vascular/farmacología , Adulto Joven
13.
BMC Palliat Care ; 17(1): 103, 2018 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-30143036

RESUMEN

BACKGROUND: Patients with Chronic Heart Failure (CHF) and patients with Chronic Obstructive Pulmonary Disease (COPD) share similar symptom burden with cancer patients, however, they are unlikely to receive palliative care (PC) services. This article examines the perceptions of health care professionals and the current practices of integrated palliative care (IPC) in Belgium. METHODS: Cardiologists and pulmonologists, working in primary care hospitals in Belgium, participated in this study with semi-structured interviews based on IPC indicators. One researcher collected, transcribed verbatim the interviews and carried out their thematic analysis. To increase the reliability of the coding, a second researcher coded a random 30% of the interviews. RESULTS: A total of 22 CHF/COPD specialists participated in the study. The results show that IPC and its potential benefits are viewed positively. A number of IPC components like the holistic approach (physical, psychological, social, spiritual aspects) via multidisciplinary teams, prognosis discussion and illness limitations, patient goals assessment, continuous goal adjustment, reduction of suffering and advanced care planning are partially implemented in several health centers. However, PC specialists are absent from such implementations and PC is still an end-of-life care. CONCLUSIONS: Misconceptions about PC and its association to death and end-of-life appear to be decisive factors for the exclusion of PC specialists and the late initiation of PC itself. The implementation of IPC components is not associated to PC, and as such, leads to suboptimal results. Improved education and enhanced communication is expected to alleviate existing challenges and thus improve the quality of life for the patients.


Asunto(s)
Personal de Salud/psicología , Medicina Integrativa/normas , Cuidados Paliativos/métodos , Percepción , Adulto , Anciano , Bélgica , Costo de Enfermedad , Femenino , Insuficiencia Cardíaca/complicaciones , Insuficiencia Cardíaca/psicología , Humanos , Medicina Integrativa/métodos , Masculino , Persona de Mediana Edad , Cuidados Paliativos/normas , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Enfermedad Pulmonar Obstructiva Crónica/psicología , Investigación Cualitativa
14.
J Proteome Res ; 16(1): 156-169, 2017 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-27351377

RESUMEN

The human acute monocytic leukemia cell line THP-1 is widely used as an in vitro phagocytic cell model because it exhibits several immune properties similar to native monocyte-derived macrophages. In this study, we investigated the alteration of N- and O-linked glycans as well as glycosphingolipids, during THP-1 differentiation, combining mass spectrometry, flow cytometry, and quantitative real-time PCR. Mass spectrometry revealed that macrophage differentiation led to a marked upregulation of expression of GM3 ganglioside as well as an increase in complex-type structures, particularly triantennary glycans, occurring at the expense of high-mannose N-glycans. Moreover, we observed a slight decrease in the proportion of multifucosylated N-glycans and α2,6-sialylation. The uncovered changes in glycosylation correlated with variations of gene expression of relevant glycosyltransferases and glycosidases including sialyltransferases, ß-N-acetylglucosaminyltransferases, fucosyltransferases, and neuraminidase. Furthermore, using flow cytometry and antibodies directed against glycan structures, we confirmed that the alteration of glycosylation occurs at the cell surface of THP-1 macrophage-like cells. Altogether, we established that macrophagic maturation of THP-1 induces dramatic modifications of the surface glycosylation pattern that may result in differential interaction of monocytic and macrophagic THP-1 with immune or bacterial lectins.


Asunto(s)
Diferenciación Celular/inmunología , Glicoesfingolípidos/química , Macrófagos/química , Monocitos/química , Polisacáridos/química , Conformación de Carbohidratos , Secuencia de Carbohidratos , Línea Celular , Fucosiltransferasas/genética , Fucosiltransferasas/inmunología , Gangliósido G(M3)/química , Gangliósido G(M3)/inmunología , Regulación de la Expresión Génica , Glicoesfingolípidos/inmunología , Glicosilación , Glicosiltransferasas/genética , Glicosiltransferasas/inmunología , Humanos , Macrófagos/citología , Macrófagos/inmunología , Manosa/química , Manosa/inmunología , Monocitos/citología , Monocitos/inmunología , N-Acetilglucosaminiltransferasas/genética , N-Acetilglucosaminiltransferasas/inmunología , Neuraminidasa/genética , Neuraminidasa/inmunología , Polisacáridos/inmunología , Ácidos Siálicos/química , Ácidos Siálicos/inmunología , Sialiltransferasas/genética , Sialiltransferasas/inmunología
15.
Ann Oncol ; 28(9): 2219-2224, 2017 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-28911062

RESUMEN

BACKGROUND: Our aim was to test the safety of cetuximab added to chemoradiation with either cisplatin or carboplatin after prior induction chemotherapy. METHODS: Patients with stage III/IV unresectable, squamous cell carcinoma of the head and neck received up to four cycles of TPF-E (cisplatin and docetaxel 75 mg/m2 on day 1 followed by 5-FU 750 mg/m2/day as a continuous infusion on days 1-5 plus cetuximab at a loading dose of 400 mg/m2 followed by a weekly dose of 250 mg/m2), with prophylactic antibiotics but no growth factors. Patients not progressing after four cycles of TPF-E were randomly assigned to radiotherapy (70 Gy over 7 weeks in 2 Gy fractions) and weekly cetuximab with either weekly cisplatin 40 mg/m2 or carboplatin, AUC of 1.5 mg/ml/min. Primary endpoint was feasibility. RESULTS: Forty-seven patients were recruited. One patient did not start TPF (hypersensitivity reaction during the cetuximab loading dose). Induction TPF-E was discontinued in 12 patients due to toxicity (6 patients), medical decision (2), death (1), patient refusal (1), protocol violation (1), co-morbidity (1). Three further patients were not randomized [progressive disease (1), protocol violation (1), toxicity and co-morbidity (1)]. Of particular interest are three patients who suffered from bowel perforation, one patient who died as results of pneumonia and septic shock, and a second patient who was found dead at home 12 days after starting TPF-E (cause of death unknown). Weekly cisplatin and carboplatin was stopped early in seven and four patients, respectively. Radiotherapy was stopped in two patients with cisplatin and interrupted in one patient with cisplatin and four patients with carboplatin. CONCLUSIONS: The addition of cetuximab to full dose TPF induction chemotherapy led to unacceptable complications and premature closing of the study. Only 34 out of 46 patients completed four cycles of TPF-E and only 30 started biochemoradiation.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Células Escamosas/terapia , Quimioradioterapia , Neoplasias de Cabeza y Cuello/terapia , Adolescente , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Área Bajo la Curva , Carboplatino/administración & dosificación , Cetuximab/administración & dosificación , Cisplatino/administración & dosificación , Cisplatino/efectos adversos , Cisplatino/uso terapéutico , Relación Dosis-Respuesta a Droga , Femenino , Fluorouracilo/administración & dosificación , Fluorouracilo/efectos adversos , Fluorouracilo/uso terapéutico , Humanos , Quimioterapia de Inducción , Masculino , Persona de Mediana Edad , Carcinoma de Células Escamosas de Cabeza y Cuello , Taxoides/administración & dosificación , Taxoides/efectos adversos , Taxoides/uso terapéutico , Adulto Joven
16.
Ann Oncol ; 28(10): 2526-2532, 2017 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-28961833

RESUMEN

BACKGROUND: In the phase III LUX-Head & Neck 1 (LUX-H&N1) trial, second-line afatinib significantly improved progression-free survival (PFS) versus methotrexate in patients with recurrent/metastatic head and neck squamous cell carcinoma (R/M HNSCC). Here, we evaluated association of prespecified biomarkers with efficacy outcomes in LUX-H&N1. PATIENTS AND METHODS: Randomized patients with R/M HNSCC and progression following ≥2 cycles of platinum therapy received afatinib (40 mg/day) or methotrexate (40 mg/m2/week). Tumor/serum samples were collected at study entry for patients who volunteered for inclusion in biomarker analyses. Tumor biomarkers, including p16 (prespecified subgroup; all tumor subsites), EGFR, HER2, HER3, c-MET and PTEN, were assessed using tissue microarray cores and slides; serum protein was evaluated using the VeriStrat® test. Biomarkers were correlated with efficacy outcomes. RESULTS: Of 483 randomized patients, 326 (67%) were included in the biomarker analyses; baseline characteristics were consistent with the overall study population. Median PFS favored afatinib over methotrexate in patients with p16-negative [2.7 versus 1.6 months; HR 0.70 (95% CI 0.50-0.97)], EGFR-amplified [2.8 versus 1.5 months; HR 0.53 (0.33-0.85)], HER3-low [2.8 versus 1.8 months; HR 0.57 (0.37-0.88)], and PTEN-high [1.6 versus 1.4 months; HR 0.55 (0.29-1.05)] tumors. Afatinib also improved PFS in combined subsets of patients with p16-negative and EGFR-amplified tumors [2.7 versus 1.5 months; HR 0.47 (0.28-0.80)], and patients with p16-negative tumors who were EGFR therapy-naïve [4.0 versus 2.4 months; HR 0.55 (0.31-0.98)]. PFS was improved in afatinib-treated patients who were VeriStrat 'Good' versus 'Poor' [2.7 versus 1.5 months; HR 0.71 (0.49-0.94)], but no treatment interaction was observed. Afatinib improved tumor response versus methotrexate in all subsets analyzed except for those with p16-positive disease (n = 35). CONCLUSIONS: Subgroups of HNSCC patients who may achieve increased benefit from afatinib were identified based on prespecified tumor biomarkers (p16-negative, EGFR-amplified, HER3-low, PTEN-high). Future studies are warranted to validate these findings. CLINICAL TRIAL REGISTRATION: NCT01345682.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas/metabolismo , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Neoplasias de Cabeza y Cuello/metabolismo , Metotrexato/administración & dosificación , Recurrencia Local de Neoplasia/tratamiento farmacológico , Recurrencia Local de Neoplasia/metabolismo , Quinazolinas/administración & dosificación , Administración Intravenosa , Administración Oral , Afatinib , Antimetabolitos Antineoplásicos/administración & dosificación , Biomarcadores de Tumor/sangre , Biopsia , Carcinoma de Células Escamosas/sangre , Carcinoma de Células Escamosas/patología , Supervivencia sin Enfermedad , Neoplasias de Cabeza y Cuello/sangre , Neoplasias de Cabeza y Cuello/patología , Humanos , Metástasis de la Neoplasia , Recurrencia Local de Neoplasia/sangre , Recurrencia Local de Neoplasia/patología , Valor Predictivo de las Pruebas , Carcinoma de Células Escamosas de Cabeza y Cuello
17.
Ann Oncol ; 27(8): 1585-93, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27084954

RESUMEN

BACKGROUND: In the phase III LUX-Head & Neck 1 (LHN1) trial, afatinib significantly improved progression-free survival (PFS) versus methotrexate in recurrent and/or metastatic (R/M) head and neck squamous cell carcinoma (HNSCC) patients progressing on/after platinum-based therapy. This report evaluates afatinib efficacy and safety in prespecified subgroups of patients aged ≥65 and <65 years. PATIENTS AND METHODS: Patients were randomized (2:1) to 40 mg/day oral afatinib or 40 mg/m(2)/week intravenous methotrexate. PFS was the primary end point; overall survival (OS) was the key secondary end point. Other end points included: objective response rate (ORR), patient-reported outcomes, tumor shrinkage, and safety. Disease control rate (DCR) was also assessed. RESULTS: Of 483 randomized patients, 27% (83 afatinib; 45 methotrexate) were aged ≥65 years (older) and 73% (239 afatinib; 116 methotrexate) <65 years (younger) at study entry. Similar PFS benefit with afatinib versus methotrexate was observed in older {median 2.8 versus 2.3 months, hazard ratio (HR) = 0.68 [95% confidence interval (CI) 0.45-1.03], P = 0.061} and younger patients [2.6 versus 1.6 months, HR = 0.79 (0.62-1.01), P = 0.052]. In older and younger patients, the median OS with afatinib versus methotrexate was 7.3 versus 6.4 months [HR = 0.84 (0.54-1.31)] and 6.7 versus 6.2 months [HR = 0.98 (0.76-1.28)]. ORRs with afatinib versus methotrexate were 10.8% versus 6.7% and 10.0% versus 5.2%; DCRs were 53.0% versus 37.8% and 47.7% versus 38.8% in older and younger patients, respectively. In both subgroups, the most frequent treatment-related adverse events were rash/acne (73%-77%) and diarrhea (70%-80%) with afatinib, and stomatitis (43%) and fatigue (31%-34%) with methotrexate. Fewer treatment-related discontinuations were observed with afatinib (each subgroup 7% versus 16%). A trend toward improved time to deterioration of global health status, pain, and swallowing with afatinib was observed in both subgroups. CONCLUSIONS: Advancing age (≥65 years) did not adversely affect clinical outcomes or safety with afatinib versus methotrexate in second-line R/M HNSCC patients. CLINICAL TRIAL REGISTRATION: NCT01345682 (ClinicalTrials.gov).


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Carcinoma de Células Escamosas/tratamiento farmacológico , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Metotrexato/administración & dosificación , Quinazolinas/administración & dosificación , Afatinib , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Carcinoma de Células Escamosas/patología , Supervivencia sin Enfermedad , Femenino , Neoplasias de Cabeza y Cuello/patología , Humanos , Masculino , Metotrexato/efectos adversos , Metástasis de la Neoplasia , Recurrencia Local de Neoplasia/tratamiento farmacológico , Recurrencia Local de Neoplasia/patología , Platino (Metal)/administración & dosificación , Platino (Metal)/efectos adversos , Quinazolinas/efectos adversos , Carcinoma de Células Escamosas de Cabeza y Cuello , Resultado del Tratamiento
18.
Eur Radiol ; 26(3): 900-9, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26162577

RESUMEN

OBJECTIVES: To compare the diagnostic accuracy of (111)In-pentetreotide-scintigraphy with (68)Ga-DOTATOC-positron emission tomography (PET)/computed tomography (CT) in patients with metastatic-neuroendocrine tumour (NET) scheduled for peptide receptor radionuclide therapy (PRRT). Incremental lesions (ILs) were defined as lesions observed on only one modality. METHODS: Fifty-three metastatic-NET-patients underwent (111)In-pentetreotide-scintigraphy (24 h post-injection; planar+single-photon emission CT (SPECT) abdomen) and whole-body (68)Ga-DOTATOC-PET/CT. SPECT and PET were compared in a lesion-by-lesion and organ-by-organ analysis, determining the total lesions and ILs for both modalities. RESULTS: Significantly more lesions were detected on (68)Ga-DOTATOC-PET/CT versus (111)In-pentetreotide-scintigraphy. More specifically, we observed 1,098 lesions on PET/CT (range: 1-105; median: 15) versus 660 on SPECT (range: 0-73, median: 9) (p<0.0001), with 439 PET-ILs (42/53 patients) and one SPECT-IL (1/53 patients). The sensitivity for PET/CT was 99.9 % (95 % CI, 99.3-100.0), for SPECT 60.0 % (95 % CI, 48.5-70.2). The organ-by-organ analysis showed that the PET-ILs were most frequently visualized in liver and skeleton. CONCLUSION: Ga-DOTATOC-PET/CT is superior for the detection of NET-metastases compared to (111)In-pentetreotide SPECT. KEY POINTS: Somatostatin receptor PET is superior to SPECT in detecting NET metastases. PET is the scintigraphic method for accurate depiction of NET tumour burden. The sensitivity of PET is twofold higher than the sensitivity of SPECT.


Asunto(s)
Tumores Neuroendocrinos/diagnóstico , Tomografía de Emisión de Positrones/métodos , Tomografía Computarizada de Emisión de Fotón Único/métodos , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias Óseas/diagnóstico , Neoplasias Óseas/secundario , Femenino , Radioisótopos de Galio , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/secundario , Masculino , Persona de Mediana Edad , Tumores Neuroendocrinos/radioterapia , Octreótido/análogos & derivados , Radiofármacos , Somatostatina/análogos & derivados
19.
Molecules ; 20(4): 6913-24, 2015 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-25913930

RESUMEN

α-Series gangliosides define a particular sub-class of glycosphingolipids containing sialic acid α2,6-linked to GalNAc residue that was isolated as a minor compound from the brain. The sialyltransferase ST6GalNAc V was cloned from mouse brain and showed α2,6-sialyltransferase activity almost exclusively for GM1b, to form GD1α and is considered as the main enzyme involved in the biosynthesis of α-series gangliosides. Recently, ST6GALNAC5 was identified as one of the genes over-expressed in breast cancer cell populations selected for their ability to produce brain metastasis. However, the capacity of human breast cancer cells to produce α-series gangliosides has never been clearly demonstrated. Here, we show by stable transfection and MS-MS analysis of total glycosphingolipids that ST6GALNAC5 expressing MDA-MB-231 breast cancer cells accumulate GD1α ganglioside (IV3Neu5Ac1, III6Neu5Ac1Gg4-Cer).


Asunto(s)
Neoplasias de la Mama/metabolismo , Gangliósido G(M1)/análogos & derivados , Sialiltransferasas/genética , Neoplasias de la Mama/genética , Línea Celular Tumoral , Femenino , Gangliósido G(M1)/metabolismo , Humanos , Espectrometría de Masas/métodos , Sialiltransferasas/metabolismo
20.
Ann Oncol ; 25(3): 682-688, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24567516

RESUMEN

BACKGROUND: Recurrent and/or metastatic squamous cell carcinoma of the head and neck (R/M-SCCHN) overexpresses αvß5 integrin. Cilengitide selectively inhibits αvß3 and αvß5 integrins and is investigated as a treatment strategy. PATIENTS AND METHODS: The phase I/II study ADVANTAGE evaluated cilengitide combined with cisplatin, 5-fluorouracil, and cetuximab (PFE) in R/M-SCCHN. The phase II part reported here was an open-label, randomized, controlled trial investigating progression-free survival (PFS). Patients received up to six cycles of PFE alone or combined with cilengitide 2000 mg once (CIL1W) or twice (CIL2W) weekly. Thereafter, patients received maintenance therapy (cilengitide arms: cilengitide plus cetuximab; PFE-alone arm: cetuximab only) until disease progression or unacceptable toxicity. RESULTS: One hundred and eighty-two patients were treated. Median PFS per investigator read was similar for CIL1W + PFE, CIL2W + PFE, and PFE alone (6.4, 5.6, and 5.7 months, respectively). Accordingly, median overall survival and objective response rates were not improved with cilengitide (12.4 months/47%, 10.6 months/27%, and 11.6 months/36%, respectively). No clinically meaningful safety differences were observed between groups. None of the tested biomarkers (expression of integrins, CD31, Ki-67, vascular endothelial growth factor receptor 2, vascular endothelial-cadherin, type IV collagen, epidermal growth factor receptor, or p16 for human papillomavirus) were predictive of outcome. CONCLUSION: Neither of the cilengitide-containing regimens demonstrated a PFS benefit over PFE alone in R/M-SCCHN patients.


Asunto(s)
Anticuerpos Monoclonales Humanizados/uso terapéutico , Carcinoma de Células Escamosas/tratamiento farmacológico , Cisplatino/uso terapéutico , Fluorouracilo/uso terapéutico , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Venenos de Serpiente/uso terapéutico , Adulto , Anciano , Anticuerpos Monoclonales Humanizados/efectos adversos , Antimetabolitos Antineoplásicos/efectos adversos , Antimetabolitos Antineoplásicos/uso terapéutico , Antineoplásicos/efectos adversos , Antineoplásicos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Biomarcadores de Tumor/análisis , Cetuximab , Cisplatino/efectos adversos , Progresión de la Enfermedad , Supervivencia sin Enfermedad , Receptores ErbB/antagonistas & inhibidores , Femenino , Fluorouracilo/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Venenos de Serpiente/efectos adversos , Carcinoma de Células Escamosas de Cabeza y Cuello , Resultado del Tratamiento
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