Person: Bragado Domingo, Paloma
Universidad Complutense de Madrid
Faculty / Institute
Bioquímica y Biología Molecular
Bioquímica y Biología Molecular
Now showing 1 - 7 of 7
- PublicationInhibition of RAC1 activity in cancer associated fibroblasts favours breast tumour development through IL-1β upregulation(Elsevier, 2021-08-19) Martínez López, Angélica; García Casas, Ana; Bragado Domingo, Paloma; Orimo, Akira; Castañeda-Saucedo, Eduardo; Castillo Lluva, SoniaCancer-associated fibroblasts (CAFs) are highly abundant stromal components in the tumour microenvironment. These cells contribute to tumorigenesis and indeed, they have been proposed as a target for anti-cancer therapies. Similarly, targeting the Rho-GTPase RAC1 has also been suggested as a potential therapeutic target in cancer. Here, we show that targeting RAC1 activity, either pharmacologically or by genetic silencing, increases the pro-tumorigenic activity of CAFs by upregulating IL-1β secretion. Moreover, inhibiting RAC1 activity shifts the CAF subtype to a more aggressive phenotype. Thus, as RAC1 suppresses the secretion of IL-1β by CAFs, reducing RAC1 activity in combination with the depletion of this cytokine should be considered as an interesting therapeutic option for breast cancer in which tumour cells retain intact IL-1β signalling..
- PublicationIn vivo production of fluorine-18 in a chicken egg tumor model of breast cancer for proton therapy range verification(Nature publishing group, 2022-04-30) España Palomares, Samuel; Sánchez Parcerisa, Daniel; Bragado Domingo, Paloma; Gutierrez Uzquiza, Álvaro; Porras Gallo, Almudena; Gutiérrez Neira, Carolina; Espinosa Rodríguez, Andrea; Valladolid Onecha, Victor; Ibáñez García, Paula Beatriz; Sánchez Tembleque, Víctor; Udías Moinelo, José Manuel; Fraile Prieto, Luis MarioRange verification of clinical protontherapy systems via positron-emission tomography (PET) is not a mature technology, suffering from two major issues: insufficient signal from low-energy protons in the Bragg peak area and biological washout of PET emitters. The use of contrast agents including O-18, Zn-68 or Cu-63, isotopes with a high cross section for low-energy protons in nuclear reactions producing PET emitters, has been proposed to enhance the PET signal in the last millimeters of the proton path. However, it remains a challenge to achieve sufficient concentrations of these isotopes in the target volume. Here we investigate the possibilities of O-18-enriched water (18-W), a potential contrast agent that could be incorporated in large proportions in live tissues by replacing regular water. We hypothesize that 18-W could also mitigate the problem of biological washout, as PET (F-18) isotopes created inside live cells would remain trapped in the form of fluoride anions (F-), allowing its signal to be detected even hours after irradiation. To test our hypothesis, we designed an experiment with two main goals: first, prove that 18-W can incorporate enough O-18 into a living organism to produce a detectable signal from F-18 after proton irradiation, and second, determine the amount of activity that remains trapped inside the cells. The experiment was performed on a chicken embryo chorioallantoic membrane tumor model of head and neck cancer. Seven eggs with visible tumors were infused with 18-W and irradiated with 8-MeV protons (range in water: 0.74 mm), equivalent to clinical protons at the end of particle range. The activity produced after irradiation was detected and quantified in a small-animal PET-CT scanner, and further studied by placing ex-vivo tumours in a gamma radiation detector. In the acquired images, specific activity of F-18 (originating from 18-W) could be detected in the tumour area of the alive chicken embryo up to 9 h after irradiation, which confirms that low-energy protons can indeed produce a detectable PET signal if a suitable contrast agent is employed. Moreover, dynamic PET studies in two of the eggs evidenced a minimal effect of biological washout, with 68% retained specific F-18 activity at 8 h after irradiation. Furthermore, ex-vivo analysis of 4 irradiated tumours showed that up to 3% of oxygen atoms in the targets were replaced by O-18 from infused 18-W, and evidenced an entrapment of 59% for specific activity of F-18 after washing, supporting our hypothesis that F- ions remain trapped within the cells. An infusion of 18-W can incorporate O-18 in animal tissues by replacing regular water inside cells, producing a PET signal when irradiated with low-energy protons that could be used for range verification in protontherapy. F-18 produced inside cells remains entrapped and suffers from minimal biological washout, allowing for a sharper localization with longer PET acquisitions. Further studies must evaluate the feasibility of this technique in dosimetric conditions closer to clinical practice, in order to define potential protocols for its use in patients.
- PublicationGermline gain‐of‐function MMP11 variant results in an aggressive form of colorectal cancer(Wiley, 2022-09-12) Martín Morales, Lorena; Manzano, Sara; Rodrigo Faus, María; Vicente Barrueco, Adrian; Lorca, Víctor; Núñez Moreno, Gonzalo; Bragado Domingo, Paloma; Porras Gallo, Almudena; Caldes, Trinidad; Garre, Pilar; Gutierrez‐Uzquiza, ÁlvaroAbstract Matrix metalloproteinase-11 (MMP11) is an enzyme with proteolytic activity against matrix and nonmatrix proteins. Although most MMPs are secreted as inactive proenzymes and are later activated extracellularly, MMP11 is activated intracellularly by furin within the constitutive secretory pathway. It is a key factor in physiological tissue remodeling and its alteration may play an important role in the progression of epithelial malignancies and other diseases. TCGA colon and colorectal adenocarcinoma data showed that upregulation of MMP11 expression correlates with tumorigenesis and malignancy. Here, we provide evidence that a germline variant in the MMP11 gene (NM_005940: c.232C>T; p.(Pro78Ser)), identified by whole exome sequencing, can increase the tumorigenic properties of colorectal cancer (CRC) cells. P78S is located in the prodomain region, which is responsible for blocking MMP11's protease activity. This variant was detected in the proband and all the cancer-affected family members analyzed, while it was not detected in healthy relatives. In silico analyses predict that P78S could have an impact on the activation of the enzyme. Furthermore, our in vitro analyses show that the expression of P78S in HCT116 cells increases tumor cell invasion and proliferation. In summary, our results show that this variant could modify the structure of the MMP11 prodomain, producing a premature or uncontrolled activation of the enzyme that may contribute to an early CRC onset in these patients. The study of this gene in other CRC cases will provide further information about its role in CRC development, which might improve patient treatment in the future.
- PublicationBreast Mammographic Density: Stromal Implications on Breast Cancer Detection and Therapy(MDPI, 2020-03-12) Fernández-Nogueira, Patricia; Mancino, Mario; Fuster, Gemma; Bragado Domingo, Paloma; Prats de Puig, Miquel; Gascón, Pere; Casado, Francisco Javier; Carbó, NeusCurrent evidences state clear that both normal development of breast tissue as well as its malignant progression need many-sided local and systemic communications between epithelial cells and stromal components. During development, the stroma, through remarkably regulated contextual signals, affects the fate of the different mammary cells regarding their specification and differentiation. Likewise, the stroma can generate tumour environments that facilitate the neoplastic growth of the breast carcinoma. Mammographic density has been described as a risk factor in the development of breast cancer and is ascribed to modifications in the composition of breast tissue, including both stromal and glandular compartments. Thus, stroma composition can dramatically affect the progression of breast cancer but also its early detection since it is mainly responsible for the differences in mammographic density among individuals. This review highlights both the pathological and biological evidences for a pivotal role of the breast stroma in mammographic density, with particular emphasis on dense and malignant stromas, their clinical meaning and potential therapeutic implications for breast cancer patients.
- PublicationC3G Is Upregulated in Hepatocarcinoma, Contributing to Tumor Growth and Progression and to HGF/MET Pathway Activation(MDPI, 2020-08-14) Sequera, Celia; Bragado Domingo, Paloma; Manzano, Sara; Arechederra, Maria; Richelme, Sylvie; Gutierrez Uzquiza, Álvaro; Sánchez Muñoz, Aránzazu; Maina, Flavio; Guerrero, Carmen; Porras Gallo, AlmudenaThe complexity of hepatocellular carcinoma (HCC) challenges the identification of disease-relevant signals. C3G, a guanine nucleotide exchange factor for Rap and other Ras proteins, plays a dual role in cancer acting as either a tumor suppressor or promoter depending on tumor type and stage. The potential relevance of C3G upregulation in HCC patients suggested by database analysis remains unknown. We have explored C3G function in HCC and the underlying mechanisms using public patient data and in vitro and in vivo human and mouse HCC models. We found that C3G is highly expressed in progenitor cells and neonatal hepatocytes, whilst being down-regulated in adult hepatocytes and re-expressed in human HCC patients, mouse HCC models and HCC cell lines. Moreover, high C3G mRNA levels correlate with tumor progression and a lower patient survival rate. C3G expression appears to be tightly modulated within the HCC program, influencing distinct cell biological properties. Hence, high C3G expression levels are necessary for cell tumorigenic properties, as illustrated by reduced colony formation in anchorage-dependent and -independent growth assays induced by permanent C3G silencing using shRNAs. Additionally, we demonstrate that C3G down-regulation interferes with primary HCC tumor formation in xenograft assays, increasing apoptosis and decreasing proliferation. In vitro assays also revealed that C3G down-regulation enhances the pro-migratory, invasive and metastatic properties of HCC cells through an epithelial-mesenchymal switch that favors the acquisition of a more mesenchymal phenotype. Consistently, a low C3G expression in HCC cells correlates with lung metastasis formation in mice. However, the subsequent restoration of C3G levels is associated with metastatic growth. Mechanistically, C3G down-regulation severely impairs HGF/MET signaling activation in HCC cells. Collectively, our results indicate that C3G is a key player in HCC. C3G promotes tumor growth and progression, and the modulation of its levels is essential to ensure distinct biological features of HCC cells throughout the oncogenic program. Furthermore, C3G requirement for HGF/MET signaling full activation provides mechanistic data on how it works, pointing out the relevance of assessing whether high C3G levels could identify HCC responders to MET inhibitors.
- PublicationC3G Protein, a New Player in Glioblastoma(MDPI, 2021-09-16) Manzano, Sara; Gutierrez Uzquiza, Álvaro; Bragado Domingo, Paloma; Cuesta Martínez, Angel; Guerrero, Carmen; Porras Gallo, AlmudenaC3G (RAPGEF1) is a guanine nucleotide exchange factor (GEF) for GTPases from the Ras superfamily, mainly Rap1, although it also acts through GEF-independent mechanisms. C3G regulates several cellular functions. It is expressed at relatively high levels in specific brain areas, playing important roles during embryonic development. Recent studies have uncovered different roles for C3G in cancer that are likely to depend on cell context, tumour type, and stage. However, its role in brain tumours remained unknown until very recently. We found that C3G expression is downregulated in GBM, which promotes the acquisition of a more mesenchymal phenotype, enhancing migration and invasion, but not proliferation. ERKs hyperactivation, likely induced by FGFR1, is responsible for this pro-invasive effect detected in C3G silenced cells. Other RTKs (Receptor Tyrosine Kinases) are also dysregulated and could also contribute to C3G effects. However, it remains undetermined whether Rap1 is a mediator of C3G actions in GBM. Various Rap1 isoforms can promote proliferation and invasion in GBM cells, while C3G inhibits migration/invasion. Therefore, other RapGEFs could play a major role regulating Rap1 activity in these tumours. Based on the information available, C3G could represent a new biomarker for GBM diagnosis, prognosis, and personalised treatment of patients in combination with other GBM molecular markers. The quantification of C3G levels in circulating tumour cells (CTCs) in the cerebrospinal liquid and/or circulating fluids might be a useful tool to improve GBM patient treatment and survival.
- PublicationInnovación Docente en la enseñanza de la Bioquímica y la Biología Molecular: Revistas digitales, clases invertidas y recursos didácticos para la enseñanza “en línea”(E-Prints Complutense, 2021-12-27) Oset Gasque, María Jesús; Bragado Domingo, Paloma; Escribano Illanes, Óscar; Escrivá Pons, Fernando; Fernández Millán, Elisa; García Redondo, Alberto; Gómez Hernández, María de la Almudena; Herrera González, Blanca María; Iniesta Serrano, María Pilar; Juan Chocano, María del Carmen de; Linares Gómez, María; Martínez Ruíz, Antonio; Pacheco González, Beatriz; Roncero Romero, Cesáreo; Sánchez Muñoz, AránzazuEn este Proyecto de Innovación Docente (PID 335/20) se han realizado tres tipos de actividades: 1. Elaboración de revistas digitales 2. Implantación de la metodología de clase invertida 3. Desarrollo de materiales docentes par la implantación de la enseñanza "en línea" y formación del profesorado. En ella han participado 15 profesores del Dpto. de Bioquímica y Biología Molecular (Sección Farmacia), de 4 asignaturas diferentes: Bioquímica Aplicada y Clínica, Bioquímica, Biología Molecular y Genética. Los resultados han sido muy satisfactorios, ya que se ha conseguido la participación de un enorme número de alumnos de todas estas asignaturas, los cuales han quedado muy contentos y satisfechos, ya que ha fomentado su autoaprendizaje, su trabajo en grupo, su conocimiento del método científico y sus habilidades como divulgadores de ciencia.