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1.
Microsc Res Tech ; 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38689392

RESUMEN

To detect hydrogen in materials at the atomic scale, atom probe tomography is now regularly used. In order to avoid cumbersome cryo-preparation to suppress diffusion, often hydrogen is charged only into the finished specimen. Here, the use of hydrogen gas over electrochemical hydrogen has the advantage that the specimen is not contaminated with an electrolyte. So far, this "charging" has been done in large, expensive systems. Here, we introduce small devices that enable the exposure of atom probe specimens to hydrogen and potentially other gases, using only very small gas volumes. This enables the operation in regular laboratory environments without additional safety measures. These devices can be used to expose the specimen to hydrogen up to 10 bar/90°C. Higher temperatures may be attained with small changes. Validation of the success of charging with these setups is demonstrated through experiments employing deuterium charging of palladium atom probe tips. RESEARCH HIGHLIGHTS: Enabling the exposure of atom probe specimens to hydrogen and potentially other gases, using only very small gas volumes. Built setups can be assembled with little money and from freely available parts, making specimen charging much easier. Validation of the success of charging with these setups is demonstrated through experiments employing deuterium charging of palladium atom probe tips.

2.
Diagnostics (Basel) ; 14(7)2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38611655

RESUMEN

BACKGROUND: Renal cell carcinoma (RCC) is among the most lethal urologic malignancies once metastatic. Current treatment approaches for metastatic RCC (mRCC) involve immune checkpoint inhibitors (ICIs) that target the PD-L1/PD-1 axis. High PD-L1 expression in tumor tissue has been identified as a negative prognostic factor in RCC. However, the role of PD-L1 as a liquid biomarker has not yet been fully explored. Herein, we analyze urine levels of PD-L1 in mRCC patients before and after either ICI therapy or surgical intervention, as well as in a series of patients with treatment-naïve RCC. PATIENTS AND METHODS: The mid-stream urine of patients with mRCC (n = 4) or treatment-naïve RCC, i.e., prior to surgery from two centers (cohort I, n = 49: cohort II, n = 29) was analyzed for PD-L1 by ELISA. The results from cohort I were compared to a control group consisting of patients treated for non-malignant urologic diseases (n = 31). In the mRCC group, urine PD-L1 levels were measured before and after tumor nephrectomy (n = 1) or before and after ICI therapy (n = 3). Exosomal PD-L1 in the urine was analyzed in selected patients by immunoblotting. RESULTS: A strong decrease in urine PD-L1 levels was found after tumor nephrectomy or following systemic treatment with ICIs. In patients with treatment-naïve RCC (cohort I), urine PD-L1 levels were significantly elevated in the RCC group in comparison to the control group (median 59 pg/mL vs. 25.7 pg/mL, p = 0.011). PD-L1 urine levels were found to be elevated, in particular, in low-grade RCCs in cohorts I and II. Exosomal PD-L1 was detected in the urine of a subset of patients. CONCLUSION: In this proof-of-concept study, we show that PD-L1 can be detected in the urine of RCC patients. Urine PD-L1 levels were found to correlate with the treatment response in mRCC patients and were significantly elevated in treatment-naïve RCC patients.

3.
Arch Argent Pediatr ; : e202310275, 2024 Apr 04.
Artículo en Inglés, Español | MEDLINE | ID: mdl-38527184

RESUMEN

Introduction. The COVID-19 pandemic has had a profound impact on the health of young people worldwide, especially on people with eating disorders (EDs) due to the stress, anxiety, and changes experienced in access to health care. Objective. To explore adolescents' perceptions on changes in their social ties and the modalities of health care for patients with EDs. Population and methods. Qualitative study using in-depth interviews with adolescents with EDs seen at a teaching hospital during the COVID-19 pandemic. Results. Fifteen adolescents were interviewed; their mean age was 18 years; 93% were girls. Anorexia nervosa was observed in 86.6%. The most relevant negative aspects perceived were discomfort with family life (80%) and dissatisfaction with social media content regarding body image and dieting (73%). The aspects perceived as positive were peer support (66%) and improvements in eating habits (66%). The main change identified regarding the management before the COVID-19 pandemic was online followup by the mental healthcare team (73%). Conclusion. The adolescent population with EDs during the mandatory social isolation period reported discomfort with family life and dissatisfaction with social media content regarding body image and dieting. Notwithstanding this, adolescents highlighted peer support and improvements in their eating habits as positive aspects.


Introducción. La pandemia por COVID-19 ha tenido un impacto profundo en la salud de la población joven de todo el mundo y especialmente en personas con trastornos de la conducta alimentaria (TCA) por situaciones de estrés, ansiedad y cambios en el acceso a la atención médica. Objetivo. Explorar las percepciones de adolescentes sobre los cambios en sus vínculos sociales y modalidades de atención en pacientes con TCA. Población y métodos. Se realizó un estudio cualitativo a través de entrevistas en profundidad a adolescentes con TCA en un hospital universitario durante la pandemia por COVID-19. Resultados. Se entrevistó a 15 adolescentes; el 93 % fueron mujeres y la mediana de edad fue 18 años. El 86,6 % tuvo anorexia nerviosa. Los aspectos negativos percibidos más importantes fueron los malestares en la convivencia familiar (80 %) y la disconformidad con los contenidos de las redes sociales sobre la imagen corporal y dietas (73 %). Los aspectos percibidos positivos fueron la ayuda de los pares (66 %) y mejoras en relación con la alimentación (66 %). El principal cambio identificado en comparación con el tratamiento recibido previo a la pandemia por COVID-19 fue el seguimiento virtual por salud mental (73 %). Conclusión. La población adolescente con TCA durante el ASPO manifestó malestar en la convivencia familiar y disconformidad en los contenidos en redes sociales sobre imagen corporal y dietas. Aunque resaltaron como aspectos positivos la ayuda de los pares y mejoras en su alimentación.

4.
Commun Chem ; 6(1): 224, 2023 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-37853170

RESUMEN

Gallium-rich supported catalytically active liquid metal solutions (SCALMS) were recently introduced as a new way towards heterogeneous single atom catalysis. SCALMS were demonstrated to exhibit a certain resistance against coking during the dehydrogenation of alkanes using Ga-rich alloys of noble metals. Here, the conceptual catalytic application of SCALMS in dry reforming of methane (DRM) is tested with non-noble metal (Co, Cu, Fe, Ni) atoms in the gallium-rich liquid alloy. This study introduces SCALMS to high-temperature applications and an oxidative reaction environment. Most catalysts were shown to undergo severe oxidation during DRM, while Ga-Ni SCALMS retained a certain level of activity. This observation is explained by a kinetically controlled redox process, namely oxidation to gallium oxide species and re-reduction via H2 activation over Ni. Consequentially, this redox process can be shifted to the metallic side when using increasing concentrations of Ni in Ga, which strongly suppresses coke formation. Density-functional theory (DFT) based ab initio molecular dynamics (AIMD) simulations were performed to confirm the increased availability of Ni at the liquid alloy-gas interface. However, leaching of gallium via the formation of volatile oxidic species during the hypothesised redox cycles was identified indicating a critical instability of Ga-Ni SCALMS for prolonged test durations.

5.
Urol Oncol ; 40(1): 8.e11-8.e18, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34325986

RESUMEN

BACKGROUND: Mutations in DNA damage repair genes, in particular genes involved in homology-directed repair, define a subgroup of men with prostate cancer with a more unfavorable prognosis but a therapeutic vulnerability to PARP inhibition. In current practice, mutational testing of prostate cancer patients is commonly done late i.e., when the tumor is castration resistant. In addition, most sequencing panels do not include TP53, one of the most crucial tumor suppressor genes in human cancer. In this proof-of-concept study, we sought to extend the clinical use of these molecular markers by exploring the early prognostic impact of mutations in TP53 and DNA damage repair genes in men with primary, nonmetastatic prostate cancer undergoing radical prostatectomy (RPX). METHODS: Tumor specimens from a cohort of 68 RPX patients with intermediate (n = 11, 16.2%) or high-risk (n = 57, 83.8%) disease were analyzed by targeted next generation sequencing using a 37 DNA damage repair and checkpoint gene panel including TP53. Sequencing results were correlated to clinicopathologic variables as well as PSA persistence or time to PSA failure. In addition, the distribution of TP53 and DNA damage repair gene mutations was analyzed in three large publicly available datasets (TCGA, MSKCC and SU2C). RESULTS: Of 68 primary prostate cancers analyzed, 23 (33.8%) were found to harbor a mutation in either TP53 (n = 12, 17.6%) or a DNA damage repair gene (n = 11, 16.2%). The vast majority of these mutations (22 of 23, 95.7%) were detected in primary tumors from patients with high-risk features. These mutations were mutually exclusive in our cohort and additional data mining suggests an enrichment of DNA damage repair gene mutations in TP53 wild-type tumors. Mutations in either TP53 or a DNA damage repair gene were associated with a significantly worse prognosis after RPX. Importantly, the presence of TP53/DNA damage repair gene mutations was an independent risk factor for PSA failure or PSA persistence in multivariate Cox regression models. CONCLUSION: TP53 or DNA damage repair gene mutations are frequently detected in primary prostate cancer with high-risk features and define a subgroup of patients with an increased risk for PSA failure or persistence after RPX. The significant adverse impact of these alterations on patient prognosis may be exploited to identify men with prostate cancer who may benefit from a more intensified treatment.


Asunto(s)
Reparación del ADN/genética , Mutación , Neoplasias de la Próstata/genética , Proteína p53 Supresora de Tumor/genética , Adulto , Anciano , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Prueba de Estudio Conceptual
6.
ACS Catal ; 11(21): 13423-13433, 2021 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-34777909

RESUMEN

Supported catalytically active liquid metal solutions (SCALMS) of Pt in Ga (2 at.-% Pt) were studied in the temperature range of 500 to 600 °C for propane dehydrogenation. A facile synthesis procedure using ultrasonication was implemented and compared to a previously reported organo-chemical route for gallium deposition. The procedure was applied to synthesize GaPt-SCALMS catalyst on silica (SiO2), alumina (Al2O3), and silicon carbide (SiC) to investigate the effect of the support material on the catalytic performance. The SiC-based SCALMS catalyst showed the highest activity, while SiO2-based SCALMS showed the highest stability and lowest cracking tendency at higher temperatures. The selectivity toward propene for the SiO2-based catalyst remained above 93% at 600 °C. The catalysts were analyzed for coke content after use by temperature-programmed oxidation (TPO) and Raman spectroscopy. While the SiC- and SiO2-supported SCALMS systems showed hardly any coke formation, the Al2O3-supported systems suffered from pronounced coking. SEM-EDX analyses of the catalysts before and after reaction indicated that no perceivable morphological changes occur during reaction. The SCALMS catalysts under investigation are compared with supported Pt and supported GaPt solid-phase catalyst, and possible deactivation pathways are discussed.

7.
PLoS One ; 16(1): e0245555, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33465106

RESUMEN

Atom probe tomography (APT) is a powerful technique to obtain 3D chemical and structural information, however the 'standard' atom probe experimental workflow involves transfer of specimens at ambient conditions. The ability to transfer air- or thermally-sensitive samples between instruments while maintaining environmental control is critical to prevent chemical or morphological changes prior to analysis for a variety of interesting sample materials. In this article, we describe a versatile transfer system that enables cryogenic- or room-temperature transfer of specimens in vacuum or atmospheric conditions between sample preparation stations, a focused ion beam system (Zeiss Crossbeam 540) and a widely used commercial atom probe system (CAMECA LEAP 4000X HR). As an example for the use of this transfer system, we present atom probe data of gallium- (Ga)-free grain boundaries in an aluminum (Al) alloy specimen prepared with a Ga-based FIB.


Asunto(s)
Métodos Analíticos de la Preparación de la Muestra/instrumentación , Frío , Microscopía , Aleaciones/química , Aluminio/química
8.
Urol Oncol ; 36(8): 365.e15-365.e26, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29887238

RESUMEN

BACKGROUND: There is mounting evidence to suggest that stromal cells play an integral role in the progression of prostate cancer (PCa). One of the most frequently altered growth factors in PCa is fibroblast growth factor-2 (FGF-2). It has previously been proposed that early stages of PCa are characterized by a primarily exogenous, that is, stromal cell-derived FGF-2 production, whereas advanced tumors rely more on an autocrine FGF-2 production. Prostate cancer progression is characterized by an increase of genomic instability including aneuploidy and structural chromosomal alterations. Herein, we address 2 problems that have not been comprehensively answered. First, we ask whether exogenous FGF-2 can directly drive genomic instability to promote PCa progression. Second, we investigate whether and to what extent stromal FGF-2 expression is maintained in advanced PCa and whether this influences tumor progression and patient prognosis. METHODS: In vitro experiments to investigate the role of FGF-2 in numerical and structural chromosomal instability were performed using immunofluorescence microscopy, fluorescence in situ hybridization and single cell electrophoresis. A human patient-derived xenograft mouse model recapitulating osteoblastic PCa bone metastasis was used for in vivo validation experiments. The prognostic role of stromal FGF-2 expression was analyzed using immunohistochemical staining of a tissue microarray with primary tumor specimens from 162 predominantly high-risk patients with PCa. RESULTS: Our results show that FGF-2 not only rapidly induces mitotic defects and numerical chromosomal imbalances but also an enhanced DNA breakage to promote chromosomal instability. Using the patient-derived xenograft model, we show that a deregulation of the FGF axis results in an increase of mitotic aberrations as well as DNA damage checkpoint activation in vivo. The FGFR inhibitor dovitinib was found to reduce numerical chromosomal instability as well as DNA breakage, thus underscoring the relevance of the FGF axis in promoting genomic instability. An overexpression of tumor cell-associated FGF-2 was detected in 52 of 162 patients (32.1%), whereas a stromal overexpression was found in 27 of 165 patients (16%). Remarkably, a strong stromal FGF-2 expression was associated with a significantly higher clinical stage and higher biochemical recurrence rate. Patients with strong stromal FGF-2 expression also had a significantly worse biochemical recurrence-free survival. CONCLUSIONS: Our results underscore that exogenous FGF-2 can shape PCa cell genomes and that stromal FGF-2 expression is detectable in a sizeable proportion of advanced PCa where it is associated with adverse clinico-pathological features. Our results highlight the impact of the tumor stroma on malignant progression and provide a rationale for a further exploration of components of the tumor stroma as therapeutic targets in PCa.


Asunto(s)
Inestabilidad Cromosómica , Factor 2 de Crecimiento de Fibroblastos/genética , Neoplasias de la Próstata/genética , Anciano , Progresión de la Enfermedad , Factor 2 de Crecimiento de Fibroblastos/metabolismo , Factor 2 de Crecimiento de Fibroblastos/farmacología , Humanos , Masculino , Pronóstico , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología
9.
Sci Rep ; 8(1): 7477, 2018 05 10.
Artículo en Inglés | MEDLINE | ID: mdl-29748622

RESUMEN

A venous tumor thrombus (VTT) is a potentially lethal complication of renal cell carcinoma (RCC) but virtually nothing is known about the underlying natural history. Based on our observation that venous thrombi contain significant numbers of viable tumor cells, we applied multiregion whole exome sequencing to a total of 37 primary tumor and VTT samples including normal tissue specimens from five consecutive patients. Our findings demonstrate mutational heterogeneity between primary tumor and VTT with 106 of 483 genes (22%) harboring functional SNVs and/or indels altered in either primary tumor or thrombus. Reconstruction of the clonal phylogeny showed clustering of tumor samples and VTT samples, respectively, in the majority of tumors. However, no new subclones were detected suggesting that pre-existing subclones of the primary tumor drive VTT formation. Importantly, we found several lines of evidence for "BRCAness" in a subset of tumors. These included mutations in genes that confer "BRCAness", a mutational signature and an increase of small indels. Re-analysis of SNV calls from the TCGA KIRC-US cohort confirmed a high frequency of the "BRCAness" mutational signature AC3 in clear cell RCC. Our findings warrant further pre-clinical experiments and may lead to novel personalized therapies for RCC patients.


Asunto(s)
Carcinoma de Células Renales/genética , Neoplasias Renales/genética , Venas Renales/patología , Transcriptoma , Trombosis de la Vena/genética , Anciano , Anciano de 80 o más Años , Carcinoma de Células Renales/irrigación sanguínea , Carcinoma de Células Renales/complicaciones , Carcinoma de Células Renales/patología , Estudios de Cohortes , Análisis Mutacional de ADN , Femenino , Regulación Neoplásica de la Expresión Génica , Genómica , Humanos , Neoplasias Renales/irrigación sanguínea , Neoplasias Renales/complicaciones , Neoplasias Renales/patología , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Trombosis de la Vena/complicaciones , Trombosis de la Vena/patología , Secuenciación del Exoma
10.
Pathobiology ; 85(3): 169-178, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29166639

RESUMEN

BACKGROUND: APOBECs (apolipoprotein B mRNA-editing catalytic polypeptides) are cytidine deaminases that have been implicated in the host defense against viruses by blocking viral replication. They have also been shown to play a role in genome hypermutation in several human cancers. An APOBEC3 hypermutation signature has been discovered in cervical cancer, which is intimately associated with infection by high-risk human papillomaviruses (HPVs). At the same time, HPV genomes themselves are subject to DNA editing by APOBECs. Similar to cervical cancer, a proportion of penile squamous cell carcinomas (SCCs) is etiologically driven by high-risk HPVs, but very little is known about the role of APOBECs in penile SCC development and progression. METHODS: A series of 34 penile SCCs was analyzed for the expression of APOBEC3A protein by immunohistochemistry. HPV genotyping was carried out using a bead-based multiplex hybridization assay preceded by BSGP5+6+ primer-based amplification. RESULTS: We found a frequent reduction of APOBEC3A protein expression in the invasive parts of the majority of HPV-negative penile SCCs. In contrast, the majority of HPV-positive penile SCCs retained APOBEC3A expression during malignant progression. CONCLUSION: Our results suggest that APOBEC3A expression is downregulated during progression towards invasiveness in HPV-negative penile SCC, but maintained in HPV-positive penile SCC. How high-risk HPV-infected tumor cells tolerate high APOBEC3A, which appears to exert tumor suppressive functions in HPV-negative penile SCCs, remains to be elucidated.


Asunto(s)
Carcinoma de Células Escamosas/metabolismo , Citidina Desaminasa/metabolismo , Regulación Neoplásica de la Expresión Génica , Papillomaviridae/aislamiento & purificación , Infecciones por Papillomavirus/complicaciones , Neoplasias del Pene/metabolismo , Proteínas/metabolismo , Carcinoma de Células Escamosas/complicaciones , Estudios de Cohortes , Alemania , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Papillomaviridae/genética , Infecciones por Papillomavirus/virología , Neoplasias del Pene/complicaciones , Estudios Retrospectivos
11.
Urol Oncol ; 36(4): 161.e19-161.e30, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29198908

RESUMEN

BACKGROUND: Overexpression of the androgen receptor (AR) splice variant 7 (AR-V7) has recently been reported to be associated with resistance to antihormonal therapy. Herein, we address the question whether tumor cells with AR-V7 expression can be detected at the time of radical prostatectomy, that is, before long-term hormonal manipulation and castration resistance, and what the potential prognostic impact on the biochemical recurrence (BCR)-free survival may be. METHODS: An anti-AR-V7 antibody was first validated in a training set of prostate cancer specimens by a comparison of AR-V7 protein to AR-V7 mRNA expression. We then analyzed nuclear AR-V7 protein expression in the primary tumors and lymph node metastases from 163 predominantly high-risk patients (cohort I) as well as the primary tumors from patients of a second, consecutive patient cohort (n = 238, cohort II) not selected for any clinicopathological features. Staining results were correlated to patient characteristics and BCR-free patient survival. RESULTS: High nuclear AR-V7 protein expression was detected in approximately 30%-40% of patients in cohort I and II at the time of radical prostatectomy. High baseline expression of nuclear AR-V7 protein was associated with an unfavorable BCR-free survival in the high-risk patient cohort I but not in the unselected consecutive cohort II. Remarkably, AR-V7 was an independent negative prognostic factor in high-risk prostate cancer patients of cohort I who were selected to receive adjuvant treatment. CONCLUSIONS: Prostate cancer cells with high nuclear AR-V7 protein expression can be detected in a substantial proportion of tumors at the time of radical prostatectomy. The presence of AR-V7-positive tumor cells is associated with an unfavorable prognosis for BCR-free survival in a high-risk patient cohort including a subgroup of patients selected to receive adjuvant therapy, in which AR-V7 was an independent negative prognosticator. Overexpression of nuclear AR-V7 protein hence identifies a subset of tumors with remarkably aggressive growth characteristics among clinically and histologically high-risk patients at the time of radical prostatectomy.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Núcleo Celular/metabolismo , Recurrencia Local de Neoplasia/mortalidad , Neoplasias de la Próstata Resistentes a la Castración/patología , Receptores Androgénicos/metabolismo , Anciano , Antagonistas de Andrógenos/uso terapéutico , Antineoplásicos/uso terapéutico , Biomarcadores de Tumor/genética , Quimioterapia Adyuvante/métodos , Supervivencia sin Enfermedad , Humanos , Calicreínas/sangre , Ganglios Linfáticos/patología , Metástasis Linfática , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/sangre , Pronóstico , Próstata/patología , Próstata/cirugía , Antígeno Prostático Específico/sangre , Prostatectomía , Neoplasias de la Próstata Resistentes a la Castración/sangre , Neoplasias de la Próstata Resistentes a la Castración/mortalidad , Neoplasias de la Próstata Resistentes a la Castración/terapia , Isoformas de Proteínas/metabolismo , ARN Mensajero/metabolismo , Receptores Androgénicos/genética , Estudios Retrospectivos , Análisis de Supervivencia
12.
Sci Rep ; 7(1): 4574, 2017 07 04.
Artículo en Inglés | MEDLINE | ID: mdl-28676659

RESUMEN

Mutations in BRCA1 or BRCA2 define a subset of prostate cancer patients. Herein, we address the question whether BRCA1/2 mutations have a predictive impact on chemotherapy with docetaxel, a widely used drug in patients with metastatic castration resistant prostate cancer (mCRPC). Fifty-three men treated with docetaxel for mCRPC were tested for somatic BRCA1/2 mutations of the primary tumor. In a subgroup of patients, BRCA1/2 protein expression was tested as a potential surrogate marker for BRCA1/2 inactivation. Eight of 53 patients (15.1%) harbored a deleterious BRCA2 mutation. No BRCA1 mutation was found. Patients with a BRCA2 mutation showed a response rate of 25% to docetaxel in comparison to 71.1% in men with wildtype BRCA2 (p = 0.019). While the time to develop castration resistance was similar in both subgroups, the overall survival was significantly shorter in patients harboring a BRCA2 mutation. No correlation between the BRCA1/2 protein expression and the response to docetaxel was found. While the presence of a BRCA2 mutation does not preclude a response to docetaxel, there is overall a significant correlation between BRCA2 inactivation and a poor response rate. Our results suggest that a close oncological monitoring of patients with BRCA2 mutations for taxane resistance is warranted.


Asunto(s)
Antineoplásicos/farmacología , Biomarcadores de Tumor , Hidrocarburos Aromáticos con Puentes/farmacología , Resistencia a Antineoplásicos/genética , Genes BRCA2 , Mutación , Neoplasias de la Próstata/genética , Taxoides/farmacología , Antineoplásicos/uso terapéutico , Hidrocarburos Aromáticos con Puentes/uso terapéutico , Línea Celular Tumoral , Terapia Combinada , Expresión Génica , Genes BRCA1 , Predisposición Genética a la Enfermedad , Humanos , Inmunohistoquímica , Masculino , Tasa de Mutación , Clasificación del Tumor , Metástasis de la Neoplasia , Estadificación de Neoplasias , Neoplasias de la Próstata/diagnóstico , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/terapia , Estudios Retrospectivos , Taxoides/uso terapéutico , Resultado del Tratamiento
13.
J Nucl Med ; 58(11): 1805-1810, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-28473595

RESUMEN

68Ga-prostate-specific membrane antigen (PSMA)-11 PET/CT represents an advanced method for the staging of primary prostate cancer (PCa) and diagnosis of recurrent or metastatic PCa. However, because of the narrow availability of 68Ga the development of alternative tracers is of high interest. The objective of this study was to examine the value of the new PET tracer 18F-PSMA-1007 for the staging of local disease by comparing it with multiparametric MRI (mpMRI) and radical prostatectomy (RP) histopathology. Methods: In 2016, 18F-PSMA-1007 PET/CT was performed in 10 men with biopsy-confirmed high-risk PCa. Nine patients underwent mpMRI in the process of primary diagnosis. Consecutively, RP was performed in all 10 men. Agreement analysis was performed retrospectively. PSMA staining was added for representative sections in RP specimen slices. Localization and agreement analysis of 18F-PSMA-1007 PET/CT, mpMRI, and RP specimens was performed by dividing the prostate into 38 sections as described in the prostate imaging reporting and data system (PI-RADS) (version 2). Sensitivity, specificity, positive predictive values, negative predictive values (NPVs), and accuracy were calculated for total and near-total agreement. Results:18F-PSMA-1007 PET/CT had an NPV of 68% and an accuracy of 75%, and mpMRI had an NPV of 88% and an accuracy of 73% for total agreement. Near-total agreement analysis resulted in an NPV of 91% and an accuracy of 93% for 18F-PSMA-1007 PET/CT and 91% and 87% for mpMRI, respectively. Retrospective combination of mpMRI and PET/CT had an accuracy of 81% for total and 93% for near-total agreement. Conclusion: Comparison with RP histopathology demonstrates that 18F-PSMA-1007 PET/CT is promising for accurate local staging of PCa.


Asunto(s)
Niacinamida/análogos & derivados , Oligopéptidos , Prostatectomía/métodos , Neoplasias de la Próstata/diagnóstico por imagen , Radiofármacos , Anciano , Anciano de 80 o más Años , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Imagen Multimodal/métodos , Tomografía de Emisión de Positrones , Valor Predictivo de las Pruebas , Próstata/patología , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/cirugía , Estudios Retrospectivos , Sensibilidad y Especificidad
14.
Urol Oncol ; 35(1): 32.e9-32.e16, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27692847

RESUMEN

BACKGROUND: Taxanes are routinely used to treat men with advanced prostate cancer, yet their molecular mode of action is poorly characterized. Taxanes stabilize microtubules and may hence interfere with a plethora of cellular processes, most notably mitosis. However, prostate cancer is typically a slowly growing tumor suggesting that additional processes play a role in the response to taxanes. METHODS: Here, we analyzed the potential effect of taxanes on microtubuli-dependent intracellular transport and signaling processes, specifically, nuclear translocation of the androgen receptor and modulation of the RAS-RAF-MEK-ERK signaling cascade. RESULTS: We show that the androgen-driven nuclear translocation of the androgen receptor remains virtually undisturbed by docetaxel in prostate cancer cells. However, we found a striking down-regulation of activated ERK1/2 together with enhanced cytotoxicity in both docetaxel or cabazitaxel-treated cells that was comparable to direct MEK kinase inhibition. Remarkably, MEK inhibition alone was less effective in inducing cytotoxicity than taxanes indicating that a down-regulation of activated ERK1/2 may be necessary but is not sufficient for taxane-induced antitumoral effects. In line with this notion, we show in a xenograft mouse model that prostate cancer cells that are resistant to docetaxel overexpress activated ERK1/2. Taken together, our findings underscore that the modulation of ERK1/2 activation, in concert with other mechanisms, plays an important role in taxane-induced antineoplastic effects on prostate cancer cells. CONCLUSIONS: These results suggest at least partially nonoverlapping effects of docetaxel and androgen deprivation therapy and hence help to understand recent clinical findings. A further elucidation of the mode of action of docetaxel would have important implications to optimize current treatment strategies and biomarker development for men with metastatic prostate cancer.


Asunto(s)
Antineoplásicos/farmacología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Neoplasias de la Próstata/metabolismo , Taxoides/farmacología , Animales , Antineoplásicos/metabolismo , Transporte Biológico/efectos de los fármacos , Línea Celular Tumoral , Docetaxel , Regulación hacia Abajo , Resistencia a Antineoplásicos , Humanos , Masculino , Neoplasias de la Próstata/tratamiento farmacológico , Sistemas de Translocación de Proteínas , Proteínas Proto-Oncogénicas p21(ras)/genética , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Receptores Androgénicos/metabolismo , Taxoides/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto , Quinasas raf/metabolismo
15.
Clin Transl Radiat Oncol ; 7: 79-82, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29594233

RESUMEN

This case report shows the high PSMA-uptake in a patient with an adenoid cystic carcinoma of the maxillary sinus. Due to the intense ligand-uptake additional information for target volume delineation was obtained and the Treatment plan for bimodal radiotherapy with carbon ions was adapted accordingly.

16.
Arch Cardiol Mex ; 84(1): 25-31, 2014.
Artículo en Español | MEDLINE | ID: mdl-24636047

RESUMEN

Cardiovascular disease remains a major cause of morbidity and mortality worldwide. Current medical practice takes into account information based on population studies and benefits observed in large populations or cohorts. However, individual patients present great differences in both toxicity and clinical efficacy that can be explained by variations in adherence, unknown drug to drug interactions and genetic variability. The latter seems to explain from 20% up to 95% of patient to patient variability. Treating patients with cardiovascular disorders faces the clinician with the challenge to include genomic analysis into daily practice. There are several examples within cardiovascular disease of treatments that can vary in toxicity or clinical usefulness based on genetic changes. One of the main factors affecting the efficacy of Clopidogrel is the phenotype associated with polymorphisms in the gene CYP 2C9. Furthermore, regarding oral anticoagulants, changes in CYP2C9 and VKORC1 play an important role in changing the clinical response to anticoagulation. When analyzing statin treatment, one of their main toxicities (myopathy) can be predicted by the SLCO1B1 polymorphism. The potential for prediction of toxicity and clinical efficacy from the use of genetic analysis warrants further studies aiming towards its inclusion in daily clinical practice.


Asunto(s)
Enfermedades Cardiovasculares/tratamiento farmacológico , Enfermedades Cardiovasculares/genética , Anticoagulantes/uso terapéutico , Clopidogrel , Humanos , Inhibidores de Agregación Plaquetaria/uso terapéutico , Polimorfismo Genético , Ticlopidina/análogos & derivados , Ticlopidina/uso terapéutico
17.
Arch. cardiol. Méx ; 84(1): 25-31, ene.-mar. 2014. tab
Artículo en Español | LILACS | ID: lil-712907

RESUMEN

La enfermedad cardiovascular representa la primera causa de morbimortalidad a nivel mundial. Actualmente, la evidencia que sustenta la implementación de determinadas intervenciones terapéuticas se origina a partir de datos provenientes de grupos poblacionales. Sin embargo, los pacientes presentan variaciones interindividuales relacionadas tanto con la eficacia como con la toxicidad ante un mismo tratamiento farmacológico. Estas variaciones pueden ser explicadas principalmente por diferencias en la adherencia, interacciones no reconocidas y diferencias genéticas. Las alteraciones en el genoma explican entre un 20 y un 95% de la variabilidad interindividual tanto en la disponibilidad como en la respuesta a fármacos. En el tratamiento de las enfermedades cardiovasculares existen diversos ejemplos de dicha variabilidad genética interindividual y su impacto en la eficacia o toxicidad de diferentes fármacos. La variabilidad genética que determina la respuesta al clopidogrel radica fundamentalmente en el polimorfismo del citocromo (CYP) 2C19. Los polimorfismos en los genes CYP 2C9 y VKORC1 explican gran parte de la variabilidad en la respuesta a los anticoagulantes dicumarínicos. Con respecto al tratamiento hipolipidemiante, el polimorfismo del gen SLCO1B1 se ha asociado a la aparición de miopatía en pacientes tratados con simvastatina. Muchos otros polimorfismos han sido postulados pero sin un impacto clínico definido hasta la fecha. La utilización de la farmacogenómica en la práctica cotidiana ofrece la oportunidad de poder predecir toxicidad o eficacia terapéutica.


Cardiovascular disease remains a major cause of morbidity and mortality worldwide. Current medical practice takes into account information based on population studies and benefits observed in large populations or cohorts. However, individual patients present great differences in both toxicity and clinical efficacy that can be explained by variations in adherence, unknown drug to drug interactions and genetic variability. The latter seems to explain from 20% up to 95% of patient to patient variability. Treating patients with cardiovascular disorders faces the clinician with the challenge to include genomic analysis into daily practice. There are several examples within cardiovascular disease of treatments that can vary in toxicity or clinical usefulness based on genetic changes. One of the main factors affecting the efficacy of Clopidogrel is the phenotype associated with polymorphisms in the gene CYP 2C9. Furthermore, regarding oral anticoagulants, changes in CYP2C9 and VKORC1 play an important role in changing the clinical response to anticoagulation. When analyzing statin treatment, one of their main toxicities (myopathy) can be predicted by the SLCO1B1 polymorphism. The potential for prediction of toxicity and clinical efficacy from the use of genetic analysis warrants further studies aiming towards its inclusion in daily clinical practice.


Asunto(s)
Humanos , Enfermedades Cardiovasculares/genética , Enfermedades Cardiovasculares/tratamiento farmacológico , Polimorfismo Genético , Ticlopidina/análogos & derivados , Ticlopidina/uso terapéutico , Inhibidores de Agregación Plaquetaria/uso terapéutico , Clopidogrel , Anticoagulantes/uso terapéutico
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