9 research outputs found
Intercellular mitochondrial transfer through nanotubules is promoted by cyclic amp (cAMP) in rat astrocytes and human glioblastoma cells
Nanotubules (Tunneling nanotubules, TnTs) are cell membrane projectionsmade of F-actin fibers of nanometric diameter (up to 1 μm),which enable cytoplasmatic connections between cells. It has beenshown that mitochondria, other organelles, and cellular componentsare transferred by TnTs in several normal and tumor cell lines. TnTsestablishment has been extensively described in nervous systemcells, as neurons and astrocytes. Published evidence indicates theexistence of mitochondrial transfer through TnTs between differentcell types, such as normal and tumoral cells. Mitochondrial passagefrom normal to tumor cells restores oxidative metabolism, decreasingtumorigenic potential. A similar effect has been observed withcAMP, a very well-known astrocytes stellation promoter, which mediatesmitochondrial biogenesis and tumor growth inhibition. Mitochondrialtransfer within TnTs in nervous system cells have not beendemonstrated so far. Then, our goal was to analyze mitochondrialtrafficking through TnTs in normal and tumoral astrocytes and apossible effect of cAMP. We used normal rat astrocytes and humanglioblastoma U87 cells. Mitochondria and actin were probed with amito-targeted green fluorescent protein and phalloidin, respectively.Astrocytes and U87 were incubated with or without 8Br-cAMP(cAMP analogue). We analyzed images by confocal microscopy andmeasured the width of actin connections between cells. We analyzedeach culture separately; astrocytes and U87 establish thick projectionscontaining mitochondria but treatment with cAMP promotes anincrease of TnTs-like connections with mitochondria inside (controlvs cAMP: astrocytes: 2.07±0.71 vs 0.85±0.21 μm, ***p<0.05; U87:2.69±1.40 vs.0.84±0.22 μm, *p<0.05, ± SD, ANOVA, Tukey test).Thus, cAMP promotes TnTs-like structures and mitochondrial passagethrough them in normal astrocytes and glioblastoma cells, suggestinga role for intercellular mitochondrial transfer through TnTs instellation process.Fil: Helfenberger, Katia Estefanía. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas; ArgentinaFil: Benzo, Yanina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas; ArgentinaFil: Duarte, Alejandra Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas; ArgentinaFil: Fuentes, Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas; ArgentinaFil: Poderoso, Juan José. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Inmunología, Genética y Metabolismo. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Inmunología, Genética y Metabolismo; ArgentinaFil: Maloberti, Paula Mariana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas; ArgentinaFil: Poderoso, Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas; ArgentinaLXV Reunión Anual de la Sociedad Argentina de Investigación Clínica; LXVIII Reunión Anual de la Sociedad Argentina de Inmunología y Reunión Anual de la Sociedad Argentina FisiologíaArgentinaSociedad Argentina de Investigación ClínicaSociedad Argentina FisiologíaSociedad Argentina de Inmunologí
El proyecto político-pedagógico del Bachillerato Popular de Jóvenes y Adultos 2 de Diciembre: plan de estudio y actividades de intervención más allá del aula
Este trabajo es una reflexión del equipo docente del Bachillerato Popular de Jóvenes y Adultos "2 de Diciembre" acerca de las prácticas desarrolladas en el marco de nuestro proyecto político - pedagógico. Para ello desplegaremos la fundamentación general del proyecto, la caracterización de la población con la que se trabaja y los objetivos políticos que implican la construcción de una identidad de clase en la cual los estudiantes se asuman como parte de la clase trabajadora con capacidad transformadora. A partir de ello, se describirán los objetivos pedagógicos que estructuran nuestro plan de estudios, explicitando el proceso de cambio de una estructura curricular tradicional (dividida en materias disciplinares) por otra dividida en 5 áreas de conocimiento, como así también la especificidad del enfoque de cada área en el marco del proyecto general. Por último, detallaremos algunas de las actividades que se implementan más allá del aula como aporte al debate acerca de cómo potenciar las intervenciones en los procesos de conocimiento de nuestra clase. En particular, se sistematizarán las actividades de integración al proyecto y de diagnóstico de los estudiantes, las actividades de conocimiento para la intervención política y las actividades de evaluación, tanto de los estudiantes como del mismo proyecto. Éstas son el resultado de la experiencia y la reflexión sobre la práctica así como también de las necesidades surgidas a partir del diálogo e intercambio mantenido con los y las estudiantes como parte de un proceso que implica conocimiento y acción, dimensiones necesarias en la construcción de la educación popular.Fil: Aguilar, Maria Luz. Bachillerato Popular de Jóvenes y Adultos 2 de Diciembre; ArgentinaFil: Burela, Paula. Bachillerato Popular de Jóvenes y Adultos 2 de Diciembre; ArgentinaFil: Carpio, Ariel. Bachillerato Popular de Jóvenes y Adultos 2 de Diciembre; ArgentinaFil: Hirsch, Dana. Bachillerato Popular de Jóvenes y Adultos 2 de Diciembre; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Ladowsky, Mariana. Bachillerato Popular de Jóvenes y Adultos 2 de Diciembre; ArgentinaFil: Inzillo, Lorena. Bachillerato Popular de Jóvenes y Adultos 2 de Diciembre; ArgentinaFil: Maloberti, Federico. Universidad de Buenos Aires. Departamento de Ciencias Exactas; ArgentinaFil: Matovich, Mariana. Bachillerato Popular de Jóvenes y Adultos 2 de Diciembre; ArgentinaFil: Ortiz, Juliana. Bachillerato Popular de Jóvenes y Adultos 2 de Diciembre; ArgentinaFil: Rivero, Maura. Bachillerato Popular de Jóvenes y Adultos 2 de Diciembre; Argentin
SARS-CoV-2 vaccines: What we know, what we can do to improve them and what we could learn from other well-known viruses
: In recent weeks, the rate of SARS-CoV-2 infections has been progressively increasing all over the globe, even in countries where vaccination programs have been strongly implemented. In these regions in 2021, a reduction in the number of hospitalizations and deaths compared to 2020 was observed. This decrease is certainly associated with the introduction of vaccination measures. The process of the development of effective vaccines represents an important challenge. Overall, the breakthrough infections occurring in vaccinated subjects are in most cases less severe than those observed in unvaccinated individuals. This review examines the factors affecting the immunogenicity of vaccines against SARS-CoV-2 and the possible role of nutrients in modulating the response of distinct immune cells to the vaccination
Association of the Genomic Profile of Medullary Thyroid Carcinoma with Tumor Characteristics and Clinical Outcomes in an International Multicenter Study
Purpose: The prognostic importance of RET and RAS mutations and their relationship to clinicopathologic parameters and outcomes in medullary thyroid carcinoma (MTC) need to be clarified. Experimental Design: A multicenter retrospective cohort study was performed utilizing data from 290 patients with MTC. The molecular profile was determined and associations were examined with clinicopathologic data and outcomes. Results: RET germ line mutations were detected in 40 patients (16.3%). Somatic RET and RAS mutations occurred in 135 (46.9%) and 57 (19.8%) patients, respectively. RETM918T was the most common somatic RET mutation (n = 75). RET somatic mutations were associated with male sex, larger tumor size, advanced American Joint Committee Cancer (AJCC) stage, vascular invasion, and high International Medullary Thyroid Carcinoma Grading System (IMTCGS) grade. When compared with other RET somatic mutations, RETM918T was associated with younger age, AJCC (eighth edition) IV, vascular invasion, extrathyroidal extension, and positive margins. RET somatic or germ line mutations were significantly associated with reduced distant metastasis-free survival on univariate analysis, but there were no significant independent associations on multivariable analysis, after adjusting for tumor grade and stage. There were no significant differences in outcomes between RET somatic and RET germ line mutations, or between RETM918T and other RET mutations. Other recurrent molecular alterations included TP53 (4.2%), ARID2 (2.9%), SETD2 (2.9%), KMT2A (2.9%), and KMT2C (2.9%). Among them, TP53 mutations were associated with decreased overall survival (OS) and disease-specific survival (DSS), independently of tumor grade and AJCC stage. Conclusions: RET somatic mutations were associated with high-grade, aggressive primary tumor characteristics, and decreased distant metastatic-free survival but this relationship was not significant after accounting for tumor grade and disease stage. RETM918T was associated with aggressive primary tumors but was not independently associated with clinical outcomes. TP53 mutation may represent an adverse molecular event associated with decreased OS and DSS in MTC, but its prognostic value needs to be confirmed in future studies
Expanding the Spectrum of <i>BRAF</i> Non-V600E Mutations in Thyroid Nodules: Evidence-Based Data from a Tertiary Referral Centre
The BRAF p.V600E mutation represents the most specific marker for papillary thyroid carcinoma and is potentially related to aggressive behavior and persistent disease. BRAF alterations other than the p.V600E are less common in thyroid carcinoma and represent an alternative mechanism of BRAF activation with unclear clinical significance. The study aims to describe the frequency and clinicopathologic characteristics of BRAF non-V600E mutations in a large cohort (1654 samples) of thyroid lesions characterized by next-generation sequencing. BRAF mutations have been found in 20.3% (337/1654) of thyroid nodules, including classic (p.V600E) mutation in 19.2% (317/1654) of samples and non-V600E variants in 1.1% of cases (19/1654). BRAF non-V600E alterations include 5 cases harboring p.K601E, 2 harboring p.V600K substitutions, 2 with a p.K601G variant, and 10 cases with other BRAF non-V600E alterations. BRAF non-V600E mutations have been reported in one case of follicular adenoma, three cases of conventional papillary thyroid carcinoma, eight cases of follicular variant of papillary carcinomas, one case of columnar cell variant papillary thyroid carcinoma, one case of oncocytic follicular carcinoma, and two bone metastasis of follicular thyroid carcinoma. We confirm that BRAF non-V600E mutations are uncommon and typically found in indolent follicular-patterned tumors. Indeed, we show that BRAF non-V600E mutations can be found in tumors with metastatic potential. However, in both aggressive cases, the BRAF mutations were concomitant with other molecular alterations, such as TERT promoter mutation
Molecular Characterization of Advanced-Stage Melanomas in Clinical Practice Using a Laboratory-Developed Next-Generation Sequencing Panel
Cutaneous melanoma is one of the most lethal tumors among skin cancers, characterized by complex genetic and molecular alterations that result in uncontrolled cell proliferation and metastatic spread. Next-generation sequencing (NGS) enables the simultaneous examination of numerous genes, making this molecular technique essential for melanoma diagnosis, prognostic stratification, and therapy planning. Herein, we present the experience with our laboratory-designed NGS panel for the routine assessment of advanced-stage melanoma. A total of 260 specimens of advanced-stage melanomas were evaluated utilizing a laboratory-developed multi-gene NGS panel, which allowed the investigation of 229 amplicons in 25 oncogene/oncosuppressor genes. The NGS panel proved to be a reliable tool, failing to produce results in only 1.2% of the samples tested. BRAF and TERT were the two more commonly altered genes in 44.0% and 59.9% of samples, respectively. In 59.3% of the mutated cases, at least two concomitant variants were detected. In eight cases, both primary lesion and metastatic disease were analyzed by NGS. In all specimens (8/8, 100%), a perfect concordance in variants harbored by the primary and recurrence lesions was observed. Finally, this study described the validity of a laboratory-developed multi-gene NGS panel built specifically for advanced-stage melanomas in ordinary clinical practice
Evaluation of an institutional series of low-grade oncocytic tumor (LOT) of the kidney and review of the mutational landscape of LOT
The 2022 WHO classification of urinary and male genital tumors introduced several novel kidney entities exhibiting eosinophilic/oncocytic features with specific mutational backgrounds. Thus, molecular techniques, such as next-generation sequencing (NGS), became more commonly used for their evaluation. We studied 12 low-grade oncocytic tumors (LOT) of the kidney (from 11 patients), identified in a cohort of 210 eosinophilic/oncocytic renal tumors, diagnosed in our institution between October 2019 and May 2023, which represented 5.7% (12/210) of all eosinophilic/oncocytic renal tumors during this period. We reviewed their clinicopathologic, histologic, and immunohistochemical features, as well as their mutational profiles. We also reviewed the literature on NGS-derived data of LOT, by selecting papers in which LOT diagnosis was rendered according to the criteria proposed initially. Median age was 65 years (mean: 63.5; range 43–79) and median tumor size was 2.0 cm (mean: 2.2; range: 0.9–3.1). All tumors were positive for PAX8, CK7, and GATA3, and negative or focally positive for CD117/KIT. We found the following gene mutations: MTOR ((6/11), 54.5%)), TSC1 ((2/11), 18.2%)), and 1 had both NOTCH1 and NOTCH4 ((1/11), 9.1%)). Wild-type status was found in 2/11 (18.2%) patients and one tumor was not analyzable. A review of 8 previous studies that included 79 LOTs revealed frequent mutations in the genes that regulate the mammalian target of rapamycin (mTOR) pathway: MTOR (32/79 (40.5%)), TSC1 (21/79 (26.6%)), and TSC2 (9/79 (11.4%)). Other mutated genes included PIK3CA, NF2, and PTEN, not typically known to affect the mTOR pathway, but potentially acting as upstream and downstream effectors. Our study shows that LOT is increasingly diagnosed in routine practice when applying the appropriate diagnostic criteria. We also confirm that the mTOR pathway is strongly implicated in the pathogenesis of this tumor mainly through MTOR, TCS1, and TSC2 mutations, but other genes could also be involved in the pathway activation, especially in LOTs without “canonical” mutations