Physiological Plasticity of Neural-Crest-Derived Stem Cells in the Adult Mammalian Carotid Body

Adult stem cell plasticity, or the ability of somatic stem cells to cross boundaries and differentiate into unrelated cell types, has been amatter of debate in the last decade. Neural-crest-derived stem cells (NCSCs) display a remarkable plasticity during development. Whether adult populations of NCSCs retain this plasticity is largely unknown. Herein, we describe that neural-crest-derived adult carotid body stem cells (CBSCs) are able to undergo endothelial differentiation in addition to their reported role in neurogenesis, contributing to both neurogenic and angiogenic processes taking place in the organ during acclimatization to hypoxia. Moreover, CBSC conversion into vascular cell types is hypoxia inducible factor (HIF) dependent and sensitive to hypoxiareleased vascular cytokines such as erythropoietin. Our data highlight a remarkable physiological plasticity in an adult population of tissue-specific stem cells and could have impact on the use of these cells for cell therapy.ERC Starting Grant: CBSCsMinisterio de Economía y Competitividad SAF2013-48535-P and SAF2016-80412-

A protocol to enrich in undifferentiated cells from neuroblastoma tumor tissue samples and cell lines

The existence of a subpopulation of undifferentiated cells with stem-like properties has been suggested in neuroblastoma tumors, but a definitive biomarker for their successful isolation is missing. Here we describe an in vitro culture system for the enrichment in undifferentiated stem-like tumor cells for subsequent functional assays. We make use of clonal non-adherent cell culture conditions together with cell sorting with specific expression markers. This protocol allows for the differential study of heterogeneous cell population in neuroblastoma tumors. For complete details on the use and execution of this protocol, please refer to Vega et al. (2019)

CD44-high neural crest stem-like cells are associated with tumour aggressiveness and poor survival in neuroblastoma tumours

BACKGROUND: Neuroblastoma is a paediatric tumour originated from sympathoadrenal precursors and characterized by its heterogeneity and poor outcome in advanced stages. Intra-tumoral cellular heterogeneity has emerged as an important feature in neuroblastoma, with a potential major impact on tumour aggressiveness and response to therapy. CD44 is an adhesion protein involved in tumour progression, metastasis and stemness in different cancers; however, there has been controversies about the significance of CD44 expression in neuroblastoma and its relationship with tumour progression. METHODS: We have performed transcriptomic analysis on patient tumour samples studying the outcome of patients with high CD44 expression. Adhesion, invasion and proliferation assays were performed in sorted CD44high neuroblastoma cells. Tumoursphere cultures have been used to enrich in undifferentiated stem-like cells and to asses self-renewal and differentiation potential. We have finally performed in vivo tumorigenic assays on cell line-derived or Patient-derived xenografts. FINDINGS: We show that high CD44 expression is associated with low survival in high-grade human neuroblastoma, independently of MYCN amplification. CD44 is expressed in a cell population with neural crest stem-like features, and with the capacity to generate multipotent, undifferentiated tumourspheres in culture. These cells are more invasive and proliferative in vitro. CD44 positive cells obtained from tumours are more tumorigenic and metastatic, giving rise to aggressive neuroblastic tumours at high frequency upon transplantation. INTERPRETATION: We describe an unexpected intra-tumoural heterogeneity within cellular entities expressing CD44 in neuroblastoma, and propose that CD44 has a role in neural crest stem-like undifferentiated cells, which can contribute to tumorigenesis and malignancy in this type of cancer. FUNDING: Research supported by grants from the "Asociación Española contra el Cáncer" (AECC), the Spanish Ministry of Science and Innovation SAF program (SAF2016-80412-P), and the European Research Council (ERC Starting Grant to RP).Spanish Ministry of Science and Innovation SAF program (SAF2016-80412-P

Neural crest derived progenitor cells contribute to tumor stroma and aggressiveness in stage 4/M neuroblastoma

Pediatric tumors arise upon oncogenic transformation of stem/progenitor cells during embryonic development. Given this scenario, the existence of non-tumorigenic stem cells included within the aberrant tumoral niche, with a potential role in tumor biology, is an intriguing and unstudied possibility. Here, we describe the presence and function of non-tumorigenic neural crest-derived progenitor cells in aggressive neuroblastoma (NB) tumors. These cells differentiate into neural crest typical mesectodermal derivatives, giving rise to tumor stroma and promoting proliferation and tumor aggressiveness. Furthermore, an analysis of gene expression profiles in stage 4/M NB revealed a neural crest stem cell (NCSC) gene signature that was associated to stromal phenotype and high probability of relapse. Thus, this NCSC gene expression signature could be used in prognosis to improve stratification of stage 4/M NB tumors. Our results might facilitate the design of new therapies by targeting NCSCs and their contribution to tumor stroma.Ministerio de Economía y Competitividad RP; Grant: SAF2013-48535-P y SAF2016- 80412-

El uso de las TIC en la formación permanente del profesorado para la mejora de su práctica docente

Esta investigación presenta el estado actual de la formación permanente del profesorado en España. Plantea la necesidad de cambios en su estructura, para adecuarla a las necesidades sociales, culturales y tecnológicas vigentes en la sociedad. Considerando el uso de las Tecnologías de la Información y la Comunicación (TIC) como medio para lograrlo. Específicamente se analiza la práctica docente del profesorado y la relación que existe entre la misma y los procesos de formación permanente. Al tomar como referencia los cambios en los contextos educativos, se propone como estrategia formativa la utilización de recursos tecnológicos, como entornos virtuales, para el desarrollo de la formación permanente de los profesores

ERK5 signalling pathway is a novel target of sorafenib: Implication in EGF biology

© 2021 The Authors.Sorafenib is a multikinase inhibitor widely used in cancer therapy with an antitumour effect related to biological processes as proliferation, migration or invasion, among others. Initially designed as a Raf inhibitor, Sorafenib was later shown to also block key molecules in tumour progression such as VEGFR and PDGFR. In addition, sorafenib has been connected with key signalling pathways in cancer such as EGFR/EGF. However, no definitive clue about the molecular mechanism linking sorafenib and EGF signalling pathway has been established so far. Our data in HeLa, U2OS, A549 and HEK293T cells, based on in silico, chemical and genetic approaches demonstrate that the MEK5/ERK5 signalling pathway is a novel target of sorafenib. In addition, our data show how sorafenib is able to block MEK5-dependent phosphorylation of ERK5 in the Ser218/Tyr220, affecting the transcriptional activation associated with ERK5. Moreover, we demonstrate that some of the effects of this kinase inhibitor onto EGF biological responses, such as progression through cell cycle or migration, are mediated through the effect exerted onto ERK5 signalling pathway. Therefore, our observations describe a novel target of sorafenib, the ERK5 signalling pathway, and establish new mechanistic insights for the antitumour effect of this multikinase inhibitor.This work was supported by grants from Fundación Leticia Castillejo Castillo, Ministerio de Ciencia, Innovación y Universidades (MCIU), Agencia Estatal de Investigación (AEI) and Fondo Europeo de Desarrollo Regional (FEDER) (RTI2018-094093-B-I00) to RSP and MJRH. OR holds a contract for accessing the Spanish System of Science, Technology, and Innovation (SECTI) funded by the University of Castilla-La Mancha (UCLM) and received partial support from the European Social Fund (FSE) through its Operative Program for Castilla-La Mancha (2007–2013). RSP and MJRH's Research Institute, and the work carried out in their laboratory, received partial support from the European Community through the FEDER. RPS and EAL hold a research predoctoral contract cofounded by the European Social Fund and UCLM. The Spanish Ministry of Economy and Competitiveness (MINECO, Project RTI2018-096724-B-C21) and the Generalitat Valenciana (PROMETEO/2016/006) support work in the Encinar´s laboratory. Authors are grateful to Dr.G- Ferrer Mayorga for her assistance in the transwell assays, and to the ‘Centro de Computación Científica’ (CCC-UAM) for letting us to take advantage of the computer cluster Cibeles (https://www.ccc.uam.es/) and for providing computing facilities

Clinico-pathological characteristics and outcomes of patients with early-onset colorectal cancer

[Background]: The rising incidence of colorectal cancer (CRC) among young patients is alarming. We aim to characterize the clinico-pathological features and outcomes of patients with early-onset CRC (EOCRC). [Methods]: We included all of the patients with pathologically confirmed diagnosis of CRC at Hospital Universitario La Paz from October 2016 to September 2020. EOCRC age cut-off was 50 years. All statistical analyses were carried out using SPSS v.25. [Results]: A total of 1152 patients were diagnosed with CRC, fifty-nine (5,1%) of them were After a median follow-up of 24 months, 279 patients have died. Median overall survival (OS) was not reached in either group (p = 0,06). Three-year OS was 80% (95%CI: 73-87) and 67 (95%CI: 65-69) in the younger and older group, respectively. In patients with localized disease that underwent surgery or other antineoplastic treatment ( n = 856), 159 events for disease-free survival (DFS) were observed. Median DFS was [Conclusions]: Patients with EOCRC are diagnosed at a more advanced stage and display distinct biological features (more prevalence of dMMR and WT tumors among others). Studies focusing on screening in this population and deeper molecular profiling are needed