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1.
Eur J Neurosci ; 59(8): 1977-1992, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38311960

RESUMEN

In a great partnership, the Federation of European Neuroscience Societies (FENS) and the Hertie Foundation organized the FENS-Hertie 2022 Winter School on 'Neuro-immune interactions in health and disease'. The school selected 27 PhD students and 13 postdoctoral fellows from 20 countries and involved 14 faculty members experts in the field. The Winter School focused on a rising field of research, the interactions between the nervous and both innate and adaptive immune systems under pathological and physiological conditions. A fine-tuned neuro-immune crosstalk is fundamental for healthy development, while disrupted neuro-immune communication might play a role in neurodegeneration, neuroinflammation and aging. However, much is yet to be understood about the underlying mechanisms of these neuro-immune interactions in the healthy brain and under pathological scenarios. In addition to new findings in this emerging field, novel methodologies and animal models were presented to foment research on neuro-immunology. The FENS-Hertie 2022 Winter School provided an insightful knowledge exchange between students and faculty focusing on the latest discoveries in the biology of neuro-immune interactions while fostering great academic and professional opportunities for early-career neuroscientists from around the world.


Asunto(s)
Neuroinmunomodulación , Neurociencias , Animales , Humanos , Encéfalo , Instituciones Académicas , Envejecimiento
2.
Chembiochem ; 25(4): e202300736, 2024 02 16.
Artículo en Inglés | MEDLINE | ID: mdl-38195841

RESUMEN

PROTAC linker design remains mostly an empirical task. We employed the PRosettaC computational software in the design of sulfonyl-fluoride-based PROTACs targeting acyl protein thioesterase 1 (APT1). The software efficiently generated ternary complex models from empirically-designed PROTACs and suggested alkyl linkers to be the preferred type of linker to target APT1. Western blotting analysis revealed efficient degradation of APT1 and activity-based protein profiling showed remarkable selectivity of an alkyl linker-based PROTAC amongst serine hydrolases. Collectively, our data suggests that combining PRosettaC and chemoproteomics can effectively assist in triaging PROTACs for synthesis and providing early data on their potency and selectivity.

3.
Cerebellum ; 2024 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-39367955

RESUMEN

Cerebellar transcranial direct current stimulation (ctDCS) has emerged as a promising, non-invasive, and safe neuromodulatory intervention capable of reducing ataxia symptoms and restoring cerebellum-motor connectivity. However, previous studies have only applied ctDCS in isolation, without association with specific training. This study aimed to assess the effect of ctDCS combined with gait training on functional mobility, balance, and symptoms and severity of ataxia. A randomized, triple-blind, sham-controlled, bi-center clinical trial was conducted with forty-four adults with cerebellar ataxia. Volunteers were randomized to receive five daily sessions of either real ctDCS (n = 11; 2 mA for 25 min) or sham ctDCS (n = 11) during gait training. Functional mobility, balance, and symptoms and severity of ataxia were assessed using the Time Up and Go test, the MiniBESTest, and the Scale for the Assessment and Rating of Ataxia (SARA), respectively, before and after the interventions. Both groups showed improvement in functional mobility, but there was no significant difference between the ctDCS and sham groups. However, the ctDCS group demonstrated significant improvements in cerebellar ataxia severity as reflected by SARA scores, particularly in tests of stance, sitting, speech disturbance, nose-finger test, and heel-shin slide test. Notably, no improvements were observed in balance. This study indicates that while ctDCS combined with gait training may improve specific symptoms of cerebellar ataxia, it does not significantly enhance overall functional mobility compared to sham treatment.

4.
Brain ; 146(7): 2672-2693, 2023 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-36848323

RESUMEN

Spinal cord injury (SCI) is an as yet untreatable neuropathology that causes severe dysfunction and disability. Cell-based therapies hold neuroregenerative and neuroprotective potential, but, although being studied in SCI patients for more than two decades, long-term efficacy and safety remain unproven, and which cell types result in higher neurological and functional recovery remains under debate. In a comprehensive scoping review of 142 reports and registries of SCI cell-based clinical trials, we addressed the current therapeutical trends and critically analysed the strengths and limitations of the studies. Schwann cells, olfactory ensheathing cells (OECs), macrophages and various types of stem cells have been tested, as well as combinations of these and other cells. A comparative analysis between the reported outcomes of each cell type was performed, according to gold-standard efficacy outcome measures like the ASIA impairment scale, motor and sensory scores. Most of the trials were in the early phases of clinical development (phase I/II), involved patients with complete chronic injuries of traumatic aetiology and did not display a randomized comparative control arm. Bone marrow stem cells and OECs were the most commonly tested cells, while open surgery and injection were the main methods of delivering cells into the spinal cord or submeningeal spaces. Transplantation of support cells, such as OECs and Schwann cells, resulted in the highest ASIA Impairment Scale (AIS) grade conversion rates (improvements in ∼40% of transplanted patients), which surpassed the spontaneous improvement rate expected for complete chronic SCI patients within 1 year post-injury (5-20%). Some stem cells, such as peripheral blood-isolated and neural stem cells, offer potential for improving patient recovery. Complementary treatments, particularly post-transplantation rehabilitation regimes, may contribute highly to neurological and functional recovery. However, unbiased comparisons between the tested therapies are difficult to draw, given the great heterogeneity of the design and outcome measures used in the SCI cell-based clinical trials and how these are reported. It is therefore crucial to standardize these trials when aiming for higher value clinical evidence-based conclusions.


Asunto(s)
Enfermedades del Sistema Nervioso , Traumatismos de la Médula Espinal , Humanos , Tratamiento Basado en Trasplante de Células y Tejidos , Recuperación de la Función , Médula Espinal , Ensayos Clínicos como Asunto
5.
J Neuroinflammation ; 20(1): 250, 2023 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-37907981

RESUMEN

Childhood represents a period of significant growth and maturation for the brain, and is also associated with a heightened risk for mild traumatic brain injuries (mTBI). There is also concern that repeated-mTBI (r-mTBI) may have a long-term impact on developmental trajectories. Using an awake closed head injury (ACHI) model, that uses rapid head acceleration to induce a mTBI, we investigated the acute effects of repeated-mTBI (r-mTBI) on neurological function and cellular proliferation in juvenile male and female Long-Evans rats. We found that r-mTBI did not lead to cumulative neurological deficits with the model. R-mTBI animals exhibited an increase in BrdU + (bromodeoxyuridine positive) cells in the dentate gyrus (DG), and that this increase was more robust in male animals. This increase was not sustained, and cell proliferation returning to normal by PID3. A greater increase in BrdU + cells was observed in the dorsal DG in both male and female r-mTBI animals at PID1. Using Ki-67 expression as an endogenous marker of cellular proliferation, a robust proliferative response following r-mTBI was observed in male animals at PID1 that persisted until PID3, and was not constrained to the DG alone. Triple labeling experiments (Iba1+, GFAP+, Brdu+) revealed that a high proportion of these proliferating cells were microglia/macrophages, indicating there was a heightened inflammatory response. Overall, these findings suggest that rapid head acceleration with the ACHI model produces an mTBI, but that the acute neurological deficits do not increase in severity with repeated administration. R-mTBI transiently increases cellular proliferation in the hippocampus, particularly in male animals, and the pattern of cell proliferation suggests that this represents a neuroinflammatory response that is focused around the mid-brain rather than peripheral cortical regions. These results add to growing literature indicating sex differences in proliferative and inflammatory responses between females and males. Targeting proliferation as a therapeutic avenue may help reduce the short term impact of r-mTBI, but there may be sex-specific considerations.


Asunto(s)
Conmoción Encefálica , Traumatismos Cerrados de la Cabeza , Humanos , Ratas , Femenino , Masculino , Animales , Niño , Conmoción Encefálica/etiología , Bromodesoxiuridina , Ratas Long-Evans , Traumatismos Cerrados de la Cabeza/complicaciones , Proliferación Celular , Inflamación/complicaciones
6.
Org Biomol Chem ; 21(7): 1531-1536, 2023 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-36722743

RESUMEN

Fluorescence imaging is a powerful and widely used method to visualize and study living organisms. However, fungi are notoriously difficult to visualize using fluorescence microscopy, given that their cell wall represents a diffusion barrier, and the synthetic organic dyes available are very limited when compared to molecular probes available for other organisms. Moreover, these dyes are usually available in only one colour, preventing co-staining experiments. To fill this gap, curcumin-based molecular probes were designed based on the rationale that curcumin is fluorescent and has moderate toxicity toward fungi, implying its ability to cross the cell wall to reach targets in the intracellular compartments. A family of boron diketonate complexes was synthesized, based on a curcumin backbone, tuning their emission color from blue to red. These probes did not present noticeable toxicity to filamentous fungus and, when applied to their visualization, readily entered the cells and precisely localized in sub-cellular organelles, enabling their visualization.


Asunto(s)
Curcumina , Curcumina/farmacología , Sondas Moleculares , Colorantes Fluorescentes , Imagen Óptica , Hongos
7.
Angew Chem Int Ed Engl ; 62(44): e202311186, 2023 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-37682023

RESUMEN

Multicomponent reactions are of utmost importance at generating a unique, wide, and complex chemical space. Herein we describe a novel multicomponent approach based on the combination of the isonitrile-tetrazine (4+1) cycloaddition and the Ugi four-component reaction to generate pyrazole amide derivatives. The scope of the reaction as well as mechanistic insights governing the 4H-pyrazol-4-imine tautomerization are provided. This multicomponent process provides access to a new chemical space of pyrazole amide derivatives and offers a tool for peptide modification and stapling.

8.
Angew Chem Int Ed Engl ; 62(28): e202304449, 2023 07 10.
Artículo en Inglés | MEDLINE | ID: mdl-37142557

RESUMEN

The demand for new biomass-derived fine and commodity chemicals propels the discovery of new methodologies and synthons. Whereas furfural and 5-hydroxymethylfurfural are cornerstones of sustainable chemistry, 3-acetamido-5-acetyl furan (3A5AF), an N-rich furan obtained from chitin biomass, remains unexplored, due to the poor reactivity of the acetyl group relative to previous furanic aldehydes. Here we developed a reactive 3-acetamido-5-furfuryl aldehyde (3A5F) and demonstrated the utility of this synthon as a source of bio-derived nitrogen-rich heteroaromatics, carbocycles, and as a bioconjugation reagent.


Asunto(s)
Furaldehído , Furanos , Biomasa , Aldehídos , Quitina
9.
J Am Chem Soc ; 144(23): 10396-10406, 2022 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-35658467

RESUMEN

Protein conjugates are valuable tools for studying biological processes or producing therapeutics, such as antibody-drug conjugates. Despite the development of several protein conjugation strategies in recent years, the ability to modify one specific amino acid residue on a protein in the presence of other reactive side chains remains a challenge. We show that monosubstituted cyclopropenone (CPO) reagents react selectively with the 1,2-aminothiol groups of N-terminal cysteine residues to give a stable 1,4-thiazepan-5-one linkage under mild, biocompatible conditions. The CPO-based reagents, all accessible from a common activated ester CPO-pentafluorophenol (CPO-PFP), allow selective modification of N-terminal cysteine-containing peptides and proteins even in the presence of internal, solvent-exposed cysteine residues. This approach enabled the preparation of a dual protein conjugate of 2×cys-GFP, containing both internal and N-terminal cysteine residues, by first modifying the N-terminal residue with a CPO-based reagent followed by modification of the internal cysteine with a traditional cysteine-modifying reagent. CPO-based reagents enabled a copper-free click reaction between two proteins, producing a dimer of a de novo protein mimic of IL2 that binds to the ß-IL2 receptor with low nanomolar affinity. Importantly, the reagents are compatible with the common reducing agent dithiothreitol (DTT), a useful property for working with proteins prone to dimerization. Finally, quantum mechanical calculations uncover the origin of selectivity for CPO-based reagents for N-terminal cysteine residues. The ability to distinguish and specifically target N-terminal cysteine residues on proteins facilitates the construction of elaborate multilabeled bioconjugates with minimal protein engineering.


Asunto(s)
Cisteína , Proteínas , Ciclopropanos , Cisteína/química , Indicadores y Reactivos , Proteínas/química
10.
J Trauma Dissociation ; 23(5): 539-558, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35416129

RESUMEN

Dissociation is a process that often occurs as a sequela of psychological trauma, and it is interrelated with psychological and behavioral problems. In the at-risk adolescent population, dissociation is often underdiagnosed and undertreated. Having reliable measures to assess this phenomenon can help in identifying adolescents at-risk and improve treatment outcomes. This study assessed the psychometric properties of the Adolescent Dissociative Experiences Scale (A-DES) with a sample of 402 Portuguese adolescents recruited from three at-risk populations. Participants completed self-report measures of trauma exposure, posttraumatic symptoms, psychological and behavioral problems, and the A-DES. A subset of the sample also completed test-retest measures. Confirmatory factor analyses revealed a best-fitting 3-factor model. Analyses revealed good internal consistencies and good agreement test-retest reliability for the scale overall and the factor-based sub-scales. Construct and predictive validity was supported with results showing that A-DES discriminates between youth reporting high versus low levels of cumulative trauma exposure and youth who meet or do not meet criteria for a probable PTSD diagnosis. Study findings replicate prior research supporting a 3-factor model of dissociation and the usefulness of A-DES to identify adolescents with dissociative symptoms. Clinical and research implications are discussed.


Asunto(s)
Trastornos Disociativos , Adolescente , Trastornos Disociativos/psicología , Análisis Factorial , Humanos , Portugal , Psicometría , Reproducibilidad de los Resultados , Encuestas y Cuestionarios
11.
J Exp Criminol ; : 1-21, 2022 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-36164649

RESUMEN

Objectives: Current knowledge about the causes of offending behavior is heavily reliant on self-reports of offending (SRO). However, methodological research on the impact of modes of administration on SRO is very scarce. Further, the existing evidence conflicts with the general knowledge about responding to sensitive questions. In this study, we aimed to test whether SRO are affected by modes of administration. Methods: We carried out a methodological experiment, with a 2 (interviewer-administered vs. self-administered surveys) × 2 (paper-and-pencil vs. computer- assisted surveys) factorial design. A total of 181 undergraduate students were randomly assigned to one of these conditions and completed the International Self-Report Delinquency 3 (ISRD3) questionnaire. Results: Findings showed an increased odds of reporting offending behavior in self-administered surveys, compared to face-to-face interviews. Paper-and-pencil and computer-assisted modes resulted in comparable estimates of offending. Conclusions: This experiment provides evidence that SRO provide more accurate estimates of offending behavior using self-administered surveys.

12.
Bioprocess Biosyst Eng ; 44(1): 209-215, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32816073

RESUMEN

Bone Marrow Tyrosine kinase in the chromosome X (BMX) is a TEC family kinase associated with numerous pathological pathways in cancer cells. Covalent inhibition of BMX activity holds promise as a therapeutic approach against cancer. To screen for potent and selective covalent BMX inhibitors, large quantities of highly pure BMX are normally required which is challenging with the currently available production and purification processes. Here, we developed a scalable production process for the human recombinant BMX (hrBMX) using the insect cell-baculovirus expression vector system. Comparable expression levels were obtained in small-scale shake flasks (13 mL) and in stirred-tank bioreactors (STB, 5 L). A two-step chromatographic-based process was implemented, reducing purification times by 75% when compared to traditional processes, while maintaining hrBMX stability. The final production yield was 24 mg of purified hrBMX per litter of cell culture, with a purity of > 99%. Product quality was assessed and confirmed through a series of biochemical and biophysical assays, including circular dichroism and dynamic light scattering. Overall, the platform herein developed was capable of generating 100 mg purified hrBMX from 5 L STB in just 34 days, thus having the potential to assist in-vitro covalent ligand high-throughput screening for BMX activity inhibition.


Asunto(s)
Reactores Biológicos , Técnicas de Cultivo de Célula , Proteínas Tirosina Quinasas/biosíntesis , Animales , Humanos , Proteínas Tirosina Quinasas/genética , Proteínas Recombinantes , Células Sf9 , Spodoptera
14.
Adv Exp Med Biol ; 1139: 83-103, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31134496

RESUMEN

In the last 20 years, the conventional view of breast cancer as a homogeneous collection of highly proliferating malignant cells was totally replaced by a model of increased complexity, which points out that breast carcinomas are tissues composed of multiple populations of transformed cells. A large diversity of host cells and structural components of the extracellular matrix constitute the mammary tumour microenvironment, which supports its growth and progression, where individual cancer cells evolve with cumulative phenotypic and genetic heterogeneity. Moreover, contributing to this heterogeneity, it has been demonstrated that breast cancers can exhibit a hierarchical organization composed of tumour cells displaying divergent lineage biomarkers and where, at the apex of this hierarchy, some neoplastic cells are able to self-renew and to aberrantly differentiate. Breast cancer stem cells (BCSCs), as they were entitled, not only drive tumourigenesis, but also mediate metastasis and contribute to therapy resistance.Recently, adding more complexity to the system, it has been demonstrated that BCSCs maintain high levels of plasticity, being able to change between mesenchymal-like and epithelial-like states in a process regulated by the tumour microenvironment. These stem cell state transitions play a fundamental role in the process of tumour metastasis, as well as in the resistance to putative therapeutic strategies to target these cells. In this chapter, it will be mainly discussed the emerging knowledge regarding the contribution of BCSCs to tumour heterogeneity, their plasticity, and the role that this plasticity can play in the establishment of distant metastasis. A major focus will also be given to potential clinical implications of these discoveries in breast cancer recurrence and to possible BCSC targeted therapeutics by the use of specific biomarkers.


Asunto(s)
Neoplasias de la Mama/patología , Células Madre Neoplásicas/citología , Microambiente Tumoral , Biomarcadores de Tumor , Transición Epitelial-Mesenquimal , Femenino , Humanos , Recurrencia Local de Neoplasia
15.
Int J Mol Sci ; 20(8)2019 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-31010154

RESUMEN

Cancer cells preferentially use aerobic glycolysis over mitochondria oxidative phosphorylation for energy production, and this metabolic reprogramming is currently recognized as a hallmark of cancer. Oncogenic signaling frequently converges with this metabolic shift, increasing cancer cells' ability to produce building blocks and energy, as well as to maintain redox homeostasis. Alterations in cell-cell and cell-extracellular matrix (ECM) adhesion promote cancer cell invasion, intravasation, anchorage-independent survival in circulation, and extravasation, as well as homing in a distant organ. Importantly, during this multi-step metastatic process, cells need to induce metabolic rewiring, in order to produce the energy needed, as well as to impair oxidative stress. Although the individual implications of adhesion molecules and metabolic reprogramming in cancer have been widely explored over the years, the crosstalk between cell adhesion molecular machinery and metabolic pathways is far from being clearly understood, in both normal and cancer contexts. This review summarizes our understanding about the influence of cell-cell and cell-matrix adhesion in the metabolic behavior of cancer cells, with a special focus concerning the role of classical cadherins, such as Epithelial (E)-cadherin and Placental (P)-cadherin.


Asunto(s)
Neoplasias/metabolismo , Neoplasias/patología , Animales , Fenómenos Biomecánicos , Adhesión Celular , Uniones Célula-Matriz/metabolismo , Progresión de la Enfermedad , Transición Epitelial-Mesenquimal , Humanos
16.
Cell Commun Signal ; 16(1): 75, 2018 11 07.
Artículo en Inglés | MEDLINE | ID: mdl-30404626

RESUMEN

BACKGROUND: Basal-like breast cancer (BLBC) is a poor prognosis subgroup of triple-negative carcinomas that still lack specific target therapies and accurate biomarkers for treatment selection. P-cadherin is frequently overexpressed in these tumors, promoting cell invasion, stem cell activity and tumorigenesis by the activation of Src-Family kinase (SRC) signaling. Therefore, our aim was to evaluate if the treatment of BLBC cells with dasatinib, the FDA approved SRC inhibitor, would impact on P-cadherin induced tumor aggressive behavior. METHODS: P-cadherin and SRC expression was evaluated in a series of invasive Breast Cancer and contingency tables and chi-square tests were performed. Cell-cell adhesion measurements were performed by Atomic Force Microscopy, where frequency histograms and Gaussian curves were applied. 2D and 3D cell migration and invasion, proteases secretion and self-renew potential were evaluated in vitro. Student's t-tests were used to determine statistically significant differences. The cadherin/catenin complex interactions were evaluated by in situ proximity-ligation assay, and statistically significant results were determined by using Mann-Whitney test with a Bonferroni correction. In vivo xenograft mouse models were used to evaluate the impact of dasatinib on tumor growth and survival. ANOVA test was used to evaluate the differences in tumor size, considering a confidence interval of 95%. Survival curves were estimated by the Kaplan-Meier's method, using the log-rank test to assess significant differences for mice overall survival. RESULTS: Our data demonstrated that P-cadherin overexpression is significantly associated with SRC activation in breast cancer cells, which was also validated in a large series of primary tumor samples. SRC activity suppression with dasatinib significantly prevented the in vitro functional effects of P-cadherin overexpressing cells, as well as their in vivo tumorigenic and metastatic ability, by increasing mice overall survival. Mechanistically, SRC inhibition affects P-cadherin downstream signaling, rescues the E-cadherin/p120-catenin complex to the cell membrane, recovering cell-cell adhesion function. CONCLUSIONS: In conclusion our findings show that targeting P-cadherin/SRC signaling and functional activity may open novel therapeutic opportunities for highly aggressive and poor prognostic basal-like breast cancer.


Asunto(s)
Neoplasias de la Mama/patología , Cadherinas/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Transducción de Señal/efectos de los fármacos , Familia-src Quinasas/antagonistas & inhibidores , Animales , Carcinogénesis/efectos de los fármacos , Cateninas/metabolismo , Adhesión Celular/efectos de los fármacos , Línea Celular Tumoral , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Dasatinib/farmacología , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Ratones , Metástasis de la Neoplasia , Catenina delta
17.
Hum Mol Genet ; 22(1): 84-95, 2013 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-23035050

RESUMEN

The gene encoding protein kinase WNK2 was recently identified to be silenced by promoter hypermethylation in gliomas and meningiomas, suggesting a tumour-suppressor role in these brain tumours. Following experimental depletion in cell lines, WNK2 was further found to control GTP-loading of Rac1, a signalling guanosine triphosphatase involved in cell migration and motility. Here we show that WNK2 promoter methylation also occurs in 17.5% (29 out of 166) of adult gliomas, whereas it is infrequent in its paediatric forms (1.6%; 1 out of 66). Re-expression of WNK2 in glioblastoma cells presenting WNK2 gene silencing reduced cell proliferation in vitro, tumour growth in vivo and also cell migration and invasion, an effect correlated with reduced activation of Rac1. In contrast, when endogenous WNK2 was depleted from glioblastoma cells with unmethylated WNK2 promoter, changes in cell morphology, an increase in invasion and activation of Rac1 were observed. Together, these results validate the WNK2 gene as a recurrent target for epigenetic silencing in glia-derived brain tumours and provide first mechanistic evidence for a tumour-suppressing role of WNK2 that is related to Rac1 signalling and tumour cell invasion and proliferation.


Asunto(s)
Neoplasias Encefálicas/genética , Metilación de ADN , Glioblastoma/genética , Invasividad Neoplásica/genética , Regiones Promotoras Genéticas , Proteínas Serina-Treonina Quinasas/genética , Proteína de Unión al GTP rac1/fisiología , Adulto , Neoplasias Encefálicas/patología , División Celular , Línea Celular Tumoral , Silenciador del Gen , Glioblastoma/patología , Humanos , Reacción en Cadena de la Polimerasa
18.
BMC Cancer ; 14: 734, 2014 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-25269858

RESUMEN

BACKGROUND: Cancer stem cells are hypoxia-resistant and present a preponderant glycolytic metabolism. These characteristics are also found in basal-like breast carcinomas (BLBC), which show increased expression of cancer stem cell markers.Recently, we demonstrated that P-cadherin, a biomarker of BLBC and a poor prognostic factor in this disease, mediates stem-like properties and resistance to radiation therapy. Thus, the aim of the present study was to evaluate if P-cadherin expression was associated to breast cancer cell populations with an adapted phenotype to hypoxia. METHODS: Immunohistochemistry was performed to address the expression of P-cadherin, hypoxic, glycolytic and acid-resistance biomarkers in primary human breast carcinomas. In vitro studies were performed using basal-like breast cancer cell lines. qRT-PCR, FACS analysis, western blotting and confocal microscopy were used to assess the expression of P-cadherin after HIF-1α stabilization, achieved by CoCl2 treatment. siRNA-mediated knockdown was used to silence the expression of several targets and qRT-PCR was employed to evaluate the effects of P-cadherin on HIF-1α signaling. P-cadherin high and low breast cancer cell populations were sorted by FACS and levels of GLUT1 and CAIX were assessed by FACS and western blotting. Mammosphere forming efficiency was used to determine the stem cell activity after specific siRNA-mediated knockdown, further confirmed by western blotting. RESULTS: We demonstrated that P-cadherin overexpression was significantly associated with the expression of HIF-1α, GLUT1, CAIX, MCT1 and CD147 in human breast carcinomas. In vitro, we showed that HIF-1α stabilization was accompanied by increased membrane expression of P-cadherin and that P-cadherin silencing led to a decrease of the mRNA levels of GLUT1 and CAIX. We also found that the cell fractions harboring high levels of P-cadherin were the same exhibiting more GLUT1 and CAIX expression. Finally, we showed that P-cadherin silencing significantly decreases the mammosphere forming efficiency in the same range as the silencing of HIF-1α, CAIX or GLUT1, validating that all these markers are being expressed by the same breast cancer stem cell population. CONCLUSIONS: Our results establish a link between aberrant P-cadherin expression and hypoxic, glycolytic and acid-resistant breast cancer cells, suggesting a possible role for this marker in cancer cell metabolism.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama/metabolismo , Cadherinas/metabolismo , Carcinoma Ductal de Mama/metabolismo , Glucólisis , Desequilibrio Ácido-Base/metabolismo , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/metabolismo , Anhidrasa Carbónica IX , Anhidrasas Carbónicas/genética , Anhidrasas Carbónicas/metabolismo , Línea Celular Tumoral , Femenino , Expresión Génica , Transportador de Glucosa de Tipo 1/metabolismo , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Fenotipo , Esferoides Celulares/metabolismo , Análisis de Matrices Tisulares
19.
J Pathol ; 229(5): 705-18, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23180380

RESUMEN

P-cadherin overexpression is associated with worse breast cancer survival, being a poor prognostic marker as well as a putative therapeutic target for the aggressive triple-negative and basal-like carcinomas (TNBCs). Previously, we have shown that P-cadherin promotes breast cancer invasion of cells where membrane E-cadherin was maintained; however, it suppresses invasion in models without endogenous cadherins, like melanomas. Here, we investigated if P-cadherin expression would interfere with the normal adhesion complex and which were the cellular/molecular consequences, constituting, in this way, a new mechanism by which E-cadherin invasive-suppressor function was disrupted. Using breast TNBC models, we demonstrated, for the first time, that P-cadherin co-localizes with E-cadherin, promoting cell invasion due to the disruption caused in the interaction between E-cadherin and cytoplasmic catenins. P-cadherin also induces cell migration and survival, modifying the expression profile of cells expressing wild-type E-cadherin and contributing to alter their cellular behaviour. Additionally, E- and P-cadherin co-expressing cells significantly enhanced in vivo tumour growth, compared with cells expressing only E- or only P-cadherin. Finally, we still found that co-expression of both molecules was significantly correlated with high-grade breast carcinomas, biologically aggressive, and with poor patient survival, being a strong prognostic factor in this disease. Our results show a role for E- and P-cadherin co-expression in breast cancer progression and highlight the potential benefit of targeting P-cadherin in the aggressive tumours expressing high levels of this protein.


Asunto(s)
Neoplasias de la Mama/metabolismo , Cadherinas/metabolismo , Animales , Antígenos CD , Neoplasias de la Mama/genética , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Cadherinas/genética , Línea Celular Tumoral , Movimiento Celular , Supervivencia Celular , Supervivencia sin Enfermedad , Femenino , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos , Ratones , Ratones Desnudos , Clasificación del Tumor , Invasividad Neoplásica , Pronóstico , Interferencia de ARN , ARN Mensajero/metabolismo , Transducción de Señal , Factores de Tiempo , Transfección , Carga Tumoral
20.
Indian J Anaesth ; 68(4): 394-396, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38586271

RESUMEN

Sickle cell disease is characterised by episodes of vaso-occlusive crisis, a painful complication. Regional anaesthesia has shown promising results in reducing opioid consumption and pain scores. Patients with vaso-occlusive crises who underwent regional anaesthesia in the paediatric intensive care unit were studied. Data regarding pain location, regional analgesia technique, the local anaesthetic used and dose, daily opioid consumption, daily pain scores, use of adjuvants and complications were recorded. The primary outcome was to evaluate the effect of regional anaesthesia on opioid consumption. In this study, we describe 10 cases, referring to six paediatric patients with the vaso-occlusive crisis who underwent regional anaesthesia for severe pain and were unresponsive to increasing doses of opioids. Six cases received epidural analgesia, three continuous peripheral nerve blocks and one received both techniques. Opioid consumption was reduced (58%), and pain scores decreased (72%), both statistically significant reductions.

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