Basement membrane-rich Organoids with functional human blood vessels are permissive niches for human breast cancer metastasis

Metastasic breast cancer is the leading cause of death by malignancy in women worldwide. Tumor metastasis is a multistep process encompassing local invasion of cancer cells at primary tumor site, intravasation into the blood vessel, survival in systemic circulation, and extravasation across the endothelium to metastasize at a secondary site. However, only a small percentage of circulating cancer cells initiate metastatic colonies. This fact, together with the inaccessibility and structural complexity of target tissues has hampered the study of the later steps in cancer metastasis. In addition, most data are derived from in vivo models where critical steps such as intravasation/extravasation of human cancer cells are mediated by murine endothelial cells. Here, we developed a new mouse model to study the molecular and cellular mechanisms underlying late steps of the metastatic cascade. We have shown that a network of functional human blood vessels can be formed by co-implantation of human endothelial cells and mesenchymal cells, embedded within a reconstituted basement membrane-like matrix and inoculated subcutaneously into immunodeficient mice. The ability of circulating cancer cells to colonize these human vascularized organoids was next assessed in an orthotopic model of human breast cancer by bioluminescent imaging, molecular techniques and immunohistological analysis. We demonstrate that disseminated human breast cancer cells efficiently colonize organoids containing a functional microvessel network composed of human endothelial cells, connected to the mouse circulatory system. Human breast cancer cells could be clearly detected at different stages of the metastatic process: initial arrest in the human microvasculature, extravasation, and growth into avascular micrometastases. This new mouse model may help us to map the extravasation process with unprecedented detail, opening the way for the identification of relevant targets for therapeutic intervention

PhDAY 2020 -FOO (Facultad de Óptica y Optometría)

Por cuarto año consecutivo los doctorandos de la Facultad de Óptica y Optometría de la Universidad Complutense de Madrid cuentan con un congreso propio organizado por y para ellos, el 4º PhDAY- FOO. Se trata de un congreso gratuito abierto en la que estos jóvenes científicos podrán presentar sus investigaciones al resto de sus compañeros predoctorales y a toda la comunidad universitaria que quiera disfrutar de este evento. Apunta en tu agenda: el 15 de octubre de 2020. En esta ocasión será un Congreso On-line para evitar que la incertidumbre asociada a la pandemia Covid-19 pudiera condicionar su celebración

Estudio de las bases moleculares de la formación del linfoma de Burkitt para la identificación de posibles marcadores diagnósticos y dianas terapéuticas

Tesis doctoral inédita leída en la Universidad Autónoma de Madrid. Facultad de Medicina. Departamento de Bioquímica. Fecha de lectura: 22 de Abril de 200

Método de diagnóstico diferencial entre el Linfoma de Burkitt y el Linfoma Difuso de Células B Grandes

Método de diagnóstico diferencial entre el Linfoma de Burkitt y el Linfoma Difuso de Células B Grandes. La presente invención se encuadra dentro del campo de la biología molecular y la medicina. Específicamente, se refiere a un método de obtención de datos útiles para el diagnóstico diferencial entre el Linfoma de Burkitt (LB) y el Linfoma Difuso de Células B Grandes (LDCBG) mediante el análisis de las formas truncadas de la proteína I2PP2A, a un método de diagnóstico diferencial entre ambos tipos de linfomas y a un kit para llevar a cabo dichos métodos.Peer reviewedonsejo Superior de Investigaciones Científicas (España), Universidad Autónoma de MadridA1 Solicitud de patentes con informe sobre el estado de la técnic

Procedimiento de identificación de pacientes con linfoma de Burkitt esporádico, procedimiento de identificación y uso de compuestos para el tratamiento de linfoma de burkitt esporádico

Fecha de solicitud: 09-04-2009.- Titular: Consejo Superior de Investigaciones Científicas (CSIC)The invention relates to a method for the effective diagnosis of patients with sporadic Burkitt's lymphoma, based on identifying protein E2F1 in biological samples from said patients, which can be performed by RT-PCR or western blot. In addition, E2F1 has been shown to play an etiopathogenic role in the aforementioned disease and, as such, E2F1-specific RNAi can be used to treat said patients.El la invención se refiere a un método para el diagnóstico eficaz de pacientes con la linfoma de Burkitt esporádico, basado en identificar la proteína E2F1 en muestras biológicas de los pacientes dichos, a que el bote sea realizado por RT-PCR o la mancha occidental. Además, E2F1 ha sido mostrado al juego al papel etiopathogenic en la enfermedad mencionada y, como tal, el bote de E2F1-specific RNAi sea utilizado tratar a pacientes dichos.Peer reviewe

E2F4 plays a key role in Burkitt lymphoma tumorigenesis

El pdf es la versión de autor.-- et al.Sporadic Burkitt lymphoma (sBL) is a rapidly growing B-cell non-Hodgkins lymphoma whose treatment requires highly aggressive therapies that often result severely toxic. Identification of proteins whose expression or function is deregulated in sBL and play a role in its formation could facilitate development of less toxic therapies. We have previously shown that E2F1 expression is deregulated in sBL. We have now investigated the mechanisms underlying E2F1 deregulation and found that the E2F sites in its promoter fail to repress its transcriptional activity in BL cells and that the transcriptional repressor E2F4 barely interacts with these sites. We also have found that E2F4 protein levels, but not those of its mRNA, are reduced in sBL cell lines relative to immortal B-cell lines. E2F4 protein expression is also decreased in 24 of 26 sBL tumor samples from patients compared with control tissues. Our data demonstrate that enforced E2F4 expression in BL cells not only diminishes E2F1 levels, but also reduces selectively the tumorigenic properties and proliferation of BL cells, while increasing their accumulation in G 2/M. Our results therefore point to E2F4 as a target for developing novel and less toxic treatments for sBL. © 2012 Macmillan Publishers Limited.M.R.C is supported by the Spanish Council for Scientific Research (CSIC) and the Spanish Ministry of Science and Innovation (Ministerio de Ciencia e Innovación; SAF2010-15126). M.A.P. and S.M-M. were supported by the Spanish Ministry of Science and Innovation (RETICC, SAF2008-03871) and the Spanish Association against Cancer (AECC).Peer Reviewe

Immunohistochemical characterization of control BME-rich organoids.

<p>Immunohistochemical characterization of explanted control BME-rich organoids using anti-CD34 (species specific: human and mouse; [39]), anti-CD45, anti-neutrophils, anti-vimentin and anti-α-SMA antibodies (Table S3). Cell nuclei were counterstained with hematoxylin. 10x and 40x images are shown.</p

Immunohistochemical characterization of human vascularized BME-rich organoids.

<p>Immunohistochemical characterization of explanted human vascularized BME-rich organoids using anti-CD34 (species specific: human and mouse; [39]), anti-CD45, anti-F4/80, anti-neutrophils, anti-vimentin and anti-α-SMA antibodies (Table S3). Cell nuclei were counterstained with hematoxylin. 10x and 40x images are shown.</p

Spontaneous metastasis from primary mammary fat pad tumors.

<p>MDA-MB-231^RLuc human breast cancer cells were implanted into the orthotopic environment of the left axillary MFP of nude mice bearing human vascularized BME-rich organoids (HVO) and control BME-rich organoids (CO), without human cells. Primary tumor growth (a, b), metastatic spread (b-e) and HVO functionality (b, c) were monitored over time <i>in vivo</i> and <i>ex vivo</i>. (a) Tumor growth curves for MDA-MB-231^RLuc (<i>n = 10</i>) orthotopic mammary tumors. (b) <i>In vivo</i> ventral coelenterazine-based R^Luc-BLI images (upper panels) and D-luciferin-based F^Luc-BLI images (lower panels) of a representative mouse. (c) <i>Ex vivo</i> coelenterazine-based R^Luc-BLI images (upper panels) and D-luciferin-based F^Luc-BLI images (lower panels) of excised lungs, inguinal lymph node (LN), spleen, liver, HVO and CO of a representative mouse. (d) Percentage of metastatic colonization and (e) tumor burden in harvested tissues (normal mouse organs and BME-rich organoids) of mice (<i>n = 8</i>) with primary tumor growth. Significant differences (*** p < 0.001).</p

Correlation between mRNA levels of Renilla Luciferase (R^Luc) and <i>ex vivo</i> coelenterazine-based R^Luc-bioluminescence of lungs (<i>n = 4</i>) and human vascularized BME-rich organoids (<i>n = 5</i>).

<p>In both cases R^Luc mRNA concentrations were well correlated (a: r = 0.829; b: r = 0.851) with <i>ex vivo</i> bioluminescence data.</p