FOSL1 promotes cholangiocarcinoma via transcriptional effectors that could be therapeutically targeted

[EN] Background & Aims: Cholangiocarcinoma (CCA) is a neoplasia of the biliary tract driven by genetic, epigenetic and transcriptional mechanisms. Herein, we investigated the role of the transcription factor FOSL1, as well as its downstream transcriptional effectors, in the development and progression of CCA. Methods: FOSL1 was investigated in human CCA clinical samples. Genetic inhibition of FOSL1 in human and mouse CCA cell lines was performed in in vitro and in vivo models using constitutive and inducible short-hairpin RNAs. Conditional FOSL1 ablation was done using a genetically engineered mouse (GEM) model of CCA (mutant KRAS and Trp53 knockout). Followup RNA and chromatin immunoprecipitation (ChIP) sequencing analyses were carried out and downstream targets were validated using genetic and pharmacological inhibition. Results: An inter-species analysis of FOSL1 in CCA was conducted. First, FOSL1 was found to be highly upregulated in human and mouse CCA, and associated with poor patient survival. Pharmacological inhibition of different signalling pathways in CCA cells converged on the regulation of FOSL1 expression. Functional experiments showed that FOSL1 is required for cell proliferation and cell cycle progression in vitro, and for tumour growth and tumour maintenance in both orthotopic and subcutaneous xenograft models. Likewise, FOSL1 genetic abrogation in a GEM model of CCA extended mouse survival by decreasing the oncogenic potential of transformed cholangiocytes. RNA and ChIP sequencing studies identified direct and indirect transcriptional effectors such as HMGCS1 and AURKA, whose genetic and pharmacological inhibition phenocopied FOSL1 loss. Conclusions: Our data illustrate the functional and clinical relevance of FOSL1 in CCA and unveil potential targets amenable to pharmacological inhibition that could enable the implementation of novel therapeutic strategies. Lay summary: Understanding the molecular mechanisms involved in cholangiocarcinoma (bile duct cancer) development and progression stands as a critical step for the development of novel therapies. Through an inter-species approach, this study provides evidence of the clinical and functional role of the transcription factor FOSL1 in cholangiocarcinoma. Moreover, we report that downstream effectors of FOSL1 are susceptible to pharmacological inhibition, thus providing new opportunities for therapeutic intervention.A.V. was supported by ADA of the University of Navarra, Spain, O.E. by FSE; MINECO; FJCI-2017-34233, Spain, R.E. by a donation from Mauge Burgos de la Iglesia’s family, Spain, and P. Olaizola by the Basque Government (PRE_2016_1_0269), Basque Country, Spain. M.J.P. was funded by ISCIII [FIS PI14; 00399, PI17; 00022] cofinanced by “Fondo Europeo de Desarrollo Regional” (FEDER), Spain; Spanish Ministry of Economy and Competitiveness (MINECO: “Ramón y Cajal” Program RYC-2015-17755), Spain. M.A.A was funded by La Caixa Foundation, HEPACARE project, Spain, ISCIII FIS PI16/01126 cofinanced by “Fondo Europeo de Desarrollo Regional” (FEDER), Spain, and “Fundación Científica de la Asociación Española Contra el Cáncer’’ (AECC Scientific Foundation) Rare Cancers 2017, Spain. J.M.B. was funded by the Spanish Carlos III Health Institute (ISCIII) (FIS PI15; 01132, PI18; 01075 and Miguel Servet Program CON14; 00129 and CPII19; 00008), Spain, co-financed by “Fondo Europeo de Desarrollo Regional” (FEDER), Spain; “Euskadi RIS3” (2019222054) and BIOEF (Basque Foundation for Innovation and Health Research: EiTB Maratoia BIO15; CA; 016; BD), Basque Country, Spain; “Fundación Científica de la Asociación Española Contra el Cáncer” (AECC Scientific Foundation) Rare Cancers 2017, Spain. S.V. was supported by FEDER; MINECO (SAF2017-89944-R), Spain, by the Government of Navarra-Health Research Department (58; 2018), Navarra, Spain, by La Caixa and Caja Navarra Foundation-CIMA agreement, Spain. None of the funding sources were involved in the decision to submit the article for publication. This article is based upon work from COST Action CA18122 European Cholangiocarcinoma Network, supported by COST (European Cooperation in Science and Technology). COST (European Cooperation in Science and Technology) is a funding agency for research and innovation networks (www.cost.eu)

Opuntia in México: Identifying Priority Areas for Conserving Biodiversity in a Multi-Use Landscape

BACKGROUND: México is one of the world's centers of species diversity (richness) for Opuntia cacti. Yet, in spite of their economic and ecological importance, Opuntia species remain poorly studied and protected in México. Many of the species are sparsely but widely distributed across the landscape and are subject to a variety of human uses, so devising implementable conservation plans for them presents formidable difficulties. Multi-criteria analysis can be used to design a spatially coherent conservation area network while permitting sustainable human usage. METHODS AND FINDINGS: Species distribution models were created for 60 Opuntia species using MaxEnt. Targets of representation within conservation area networks were assigned at 100% for the geographically rarest species and 10% for the most common ones. Three different conservation plans were developed to represent the species within these networks using total area, shape, and connectivity as relevant criteria. Multi-criteria analysis and a metaheuristic adaptive tabu search algorithm were used to search for optimal solutions. The plans were built on the existing protected areas of México and prioritized additional areas for management for the persistence of Opuntia species. All plans required around one-third of México's total area to be prioritized for attention for Opuntia conservation, underscoring the implausibility of Opuntia conservation through traditional land reservation. Tabu search turned out to be both computationally tractable and easily implementable for search problems of this kind. CONCLUSIONS: Opuntia conservation in México require the management of large areas of land for multiple uses. The multi-criteria analyses identified priority areas and organized them in large contiguous blocks that can be effectively managed. A high level of connectivity was established among the prioritized areas resulting in the enhancement of possible modes of plant dispersal as well as only a small number of blocks that would be recommended for conservation management

Un Modelo de Prácticas para analizar el Proceso Social de Institucionalización Escolar del Conocimiento Matemático

El proceso de transición de un saber matemático desde que es concebido y desarrollado en el ámbito científico hasta su difusión en las aulas ha sido estudiado por diversos autores y desde diferentes perspectivas de la Matemática Educativa. En este artículo se describe un marco teórico-metodológico que permite analizar ese proceso, que hemos denominado proceso social de institucionalización, poniendo el foco de atención en las prácticas de los actores involucrados en cada uno de sus momentos. El modelo se desarrolla bajo la perspectiva socioepistemológica y se apoya en la teoría del análisis del discurso como acción social para estudiar el discurso matemático escolar.En particular, se desarrolla la manera en que se ha empleado el marco teórico-metodológico para analizar el proceso social de institucionalización del concepto de límite en el contexto educativo uruguayo. Se explora, a su vez, su posible extensión al proceso de institucionalización que atraviesan otros saberes matemáticos, en otros contextos socioculturales

Further exploring the "sting of the scorpion": hydride migration and subsequent rearrangement of norbornadiene to nortricyclyl on rhodium(i)

A new boron-based flexible scorpionate ligand based upon 7-azaindole, Li[Ph(H)B(azaindolyl)2] (Li[phBai]), has been prepared. This ligand, together with the previously reported ligand K[HB(azaindolyl) 3] (K[Tai]), have been used to prepare a range of monovalent group 9 transition-metal complexes. The complexes [M(COD){K3N,N,H-Ph(H) B(azaindolyl)2}] (where M = rhodium, iridium and COD = 1,5-cyclooctadiene) and [Rh(NBD){K3N,N,H-HB(R)(azaindolyl) 2}] (where NBD = 2,5-norbornadiene and R = Ph, azaindolyl) have been prepared. Structural characterization of [M(COD){K3NNH-Ph(H) B(azaindolyl)2}] (where M = rhodium, iridium) and [Rh(NBD){k 3N, N, H-HB(azaindolyl)3}] reveal strong interactions of the B-H functional group with the metal centers, particularly in the case of [Ir(COD){K3N,N,H-Ph(H)B(azaindolyl)2}]. The complex [Rh(NBD){K3N,N,H-HB(azaindolyl)3}] undergoes a further reaction, resulting from hydride migration from boron to the norbornadiene group. Subsequent rearrangement results in the formation of the rhodium-nortricyclyl complex [Rh(nortricyclyl){k4 N,N,-B,N-B(azaindolyl)3}], providing the first nitrogen-based metallaboratrane complex to contain the tetradentate (K4N,N,B,N) coordination mode