Polimorfismos del gen CLEC7A y riesgo de infección fúngica

Memoria del trabajo de investigación para optar al Título de Máster en Investigación Biomédica presentado por Cristina de Ramón Sánchez en la Universidad de Valladolid, Instituto de Biología y Genética Molecular (IBGM), Dpto. Daño tisular inmune e Inmunidad Innata.Los pacientes con enfermedades oncohematológicas tienen mayor riesgo de padecer infecciones fúngicas que la población general debido a la inmunosupresión producida por la propia enfermedad y a los efectos indeseables de los tratamientos que reciben. Esta combinación de factores de riesgo implica altas tasas de comorbilidad y mortalidad por lo que sería necesario establecer estrategias de prevención estandarizadas y fundamentadas en estudios con evidencia científica. Las infecciones fúngicas más frecuentes son las producidas por Aspergillus en el caso de los pacientes sometidos a trasplante de médula y por Candida en situaciones más convencionales, aunque infecciones por Cryptococcus y Pneumocystis jiroveci no son inusuales.Peer Reviewe

Polimorfismos del gen CLEC7A y riesgo de infección fúngica

Los pacientes con enfermedades oncohematológicas tienen mayor riesgo de padecer infecciones fúngicas que la población general debido a la inmunosupresión producida por la propia enfermedad y a los efectos indeseables de los tratamientos que reciben. Esta combinación de factores de riesgo implica altas tasas de comorbilidad y mortalidad por lo que sería necesario establecer estrategias de prevención estandarizadas y fundamentadas en estudios con evidencia científica. Las infecciones fúngicas más frecuentes son las producidas por Aspergillus en el caso de los pacientes sometidos a trasplante de médula y por Candida en situaciones más convencionales, aunque infecciones por Cryptococcus y Pneumocystis jiroveci no son inusuales.Máster en Investigación Biomédic

PHF2 regulates homology-directed DNA repair by controlling the resection of DNA double strand breaks

Post-translational histone modifications and chromatin remodelling play a critical role controlling the integrity of the genome. Here, we identify histone lysine demethylase PHF2 as a novel regulator of the DNA damage response by regulating DNA damage-induced focus formation of 53BP1 and BRCA1, critical factors in the pathway choice for DNA double strand break repair. PHF2 knockdown leads to impaired BRCA1 focus formation and delays the resolution of 53BP1 foci. Moreover, irradiation-induced RPA phosphorylation and focus formation, as well as localization of CtIP, required for DNA end resection, to sites of DNA lesions are affected by depletion of PHF2. These results are indicative of a defective resection of double strand breaks and thereby an impaired homologous recombination upon PHF2 depletion. In accordance with these data, Rad51 focus formation and homology-directed double strand break repair is inhibited in cells depleted for PHF2. Importantly, we demonstrate that PHF2 knockdown decreases CtIP and BRCA1 protein and mRNA levels, an effect that is dependent on the demethylase activity of PHF2. Furthermore, PHF2-depleted cells display genome instability and are mildly sensitive to the inhibition of PARP. Together these results demonstrate that PHF2 promotes DNA repair by homologous recombination by controlling CtIP-dependent resection of double strand breaks.España Ministerio de Ciencia e Innovacion SAF2016-80626-REspaña, Fundación Canaria Instituto de Investigación Sanitaria de Canarias (FIISC) [PIFUN16/18

Internal translation of the connexin 43 transcript

Connexin 43 (Cx43), the most widely expressed gap junction protein, is associated with a number of physiological and pathological conditions. Many functions of Cx43 have been shown to be independent of gap junction formation and only require the expression of Cx43 C-terminal fragments. Recent evidence demonstrated that naturally occurring C-terminal isoforms can be generated via internal translation. Here, we confirm that C-terminal domains of Cx43, particularly the major 20-kDa isoform, can be independently generated and regulated by internal translation of the same single GJA1 gene transcript that encodes full-length Cx43. Through direct RNA transfection experiments, we provide evidence that internal translation is not due to a bona fide cap-independent IRES-mediated mechanism, as upstream ribosomal scanning or translation is required. In addition to the mTOR pathway, we show for the first time, using both inhibitors and cells from knockout mice, that the Mnk1/2 pathway regulates the translation of the main 20-kDa isoform. Internal translation of the Cx43 transcript occurs but is not cap-independent and requires translation upstream of the internal start codon. In addition to the PI3K/AKT/mTOR pathway, the major 20-kDa isoform is regulated by the Mnk1/2 pathway. Our results have major implications for past and future studies escribing gap junction-independent functions of Cx43 in cancer and other pathological conditions. This study provides further clues to the signalling pathways that regulate internal mRNA translation, an emerging mechanism that allows for increased protein diversity and functional complexity from a single mRNA transcript

Nanoparticle-cell-nanoparticle communication by stigmergy to enhance poly(I:C) induced apoptosis in cancer cells

[EN] Nanoparticle-cell-nanoparticle communication by stigmergy was demonstrated using two capped nanodevices. The first community of nanoparticles (i.e.S(RA)(IFN)) is loaded with 9-cis-retinoic acid and capped with interferon-gamma, whereas the second community of nanoparticles (i.e.S(sulf)(PIC)) is loaded with sulforhodamine B and capped with poly(I:C). The uptake ofS(RA)(IFN)by SK-BR-3 breast cancer cells enhanced the expression of TLR3 receptor facilitating the subsequent uptake ofS(sulf)(PIC)and cell killing.We thank the Spanish Government (projects RTI2018-100910-B-C41 and RTI2018-101599-B-C22 (MCUI/FEDER, EU)), Generalitat Valenciana (project PROMETEO2018/024) and CIBER-BBN (project NANOCOMMUNITY) for support. A. U. and C. G are grateful to the Ministry of Education, Culture and Sport for her doctoral FPU grant.Ultimo, A.; De La Torre-Paredes, C.; Giménez, C.; Aznar, E.; Coll, C.; Marcos Martínez, MD.; Murguía, JR.... (2020). Nanoparticle-cell-nanoparticle communication by stigmergy to enhance poly(I:C) induced apoptosis in cancer cells. Chemical Communications. 56(53):7273-7276. https://doi.org/10.1039/d0cc02795bS727372765653Schaming, D., & Remita, H. (2015). Nanotechnology: from the ancient time to nowadays. Foundations of Chemistry, 17(3), 187-205. doi:10.1007/s10698-015-9235-yHauert, S., & Bhatia, S. N. (2014). Mechanisms of cooperation in cancer nanomedicine: towards systems nanotechnology. Trends in Biotechnology, 32(9), 448-455. doi:10.1016/j.tibtech.2014.06.010Theraulaz, G., & Bonabeau, E. (1999). A Brief History of Stigmergy. Artificial Life, 5(2), 97-116. doi:10.1162/106454699568700Llopis-Lorente, A., Díez, P., Sánchez, A., Marcos, M. D., Sancenón, F., Martínez-Ruiz, P., … Martínez-Máñez, R. (2017). Interactive models of communication at the nanoscale using nanoparticles that talk to one another. Nature Communications, 8(1). doi:10.1038/ncomms15511Luis, B., Llopis‐Lorente, A., Rincón, P., Gadea, J., Sancenón, F., Aznar, E., … Martínez‐Máñez, R. (2019). An Interactive Model of Communication between Abiotic Nanodevices and Microorganisms. Angewandte Chemie International Edition, 58(42), 14986-14990. doi:10.1002/anie.201908867De la Torre, C., Domínguez-Berrocal, L., Murguía, J. R., Marcos, M. D., Martínez-Máñez, R., Bravo, J., & Sancenón, F. (2018). ϵ -Polylysine-Capped Mesoporous Silica Nanoparticles as Carrier of the C 9h Peptide to Induce Apoptosis in Cancer Cells. Chemistry - A European Journal, 24(8), 1890-1897. doi:10.1002/chem.201704161García-Fernández, A., García-Laínez, G., Ferrándiz, M. L., Aznar, E., Sancenón, F., Alcaraz, M. J., … Orzáez, M. (2017). Targeting inflammasome by the inhibition of caspase-1 activity using capped mesoporous silica nanoparticles. Journal of Controlled Release, 248, 60-70. doi:10.1016/j.jconrel.2017.01.002Murugan, C., Rayappan, K., Thangam, R., Bhanumathi, R., Shanthi, K., Vivek, R., … Kannan, S. (2016). Combinatorial nanocarrier based drug delivery approach for amalgamation of anti-tumor agents in breast cancer cells: an improved nanomedicine strategy. Scientific Reports, 6(1). doi:10.1038/srep34053Van Rijt, S. H., Bölükbas, D. A., Argyo, C., Datz, S., Lindner, M., Eickelberg, O., … Meiners, S. (2015). Protease-Mediated Release of Chemotherapeutics from Mesoporous Silica Nanoparticles to ex Vivo Human and Mouse Lung Tumors. ACS Nano, 9(3), 2377-2389. doi:10.1021/nn5070343Llopis-Lorente, A., Lozano-Torres, B., Bernardos, A., Martínez-Máñez, R., & Sancenón, F. (2017). Mesoporous silica materials for controlled delivery based on enzymes. Journal of Materials Chemistry B, 5(17), 3069-3083. doi:10.1039/c7tb00348jBianchi, F., Pretto, S., Tagliabue, E., Balsari, A., & Sfondrini, L. (2017). Exploiting poly(I:C) to induce cancer cell apoptosis. Cancer Biology & Therapy, 18(10), 747-756. doi:10.1080/15384047.2017.1373220Ultimo, A., Giménez, C., Bartovsky, P., Aznar, E., Sancenón, F., Marcos, M. D., … Murguía, J. R. (2016). Targeting Innate Immunity with dsRNA-Conjugated Mesoporous Silica Nanoparticles Promotes Antitumor Effects on Breast Cancer Cells. Chemistry - A European Journal, 22(5), 1582-1586. doi:10.1002/chem.201504629Bernardo, A. R., Cosgaya, J. M., Aranda, A., & Jiménez-Lara, A. M. (2013). Synergy between RA and TLR3 promotes type I IFN-dependent apoptosis through upregulation of TRAIL pathway in breast cancer cells. Cell Death & Disease, 4(1), e479-e479. doi:10.1038/cddis.2013.5Clarke, N., Jimenez-Lara, A. M., Voltz, E., & Gronemeyer, H. (2004). Tumor suppressor IRF-1 mediates retinoid and interferon anticancer signaling to death ligand TRAIL. The EMBO Journal, 23(15), 3051-3060. doi:10.1038/sj.emboj.7600302Kajita, A. i., Morizane, S., Takiguchi, T., Yamamoto, T., Yamada, M., & Iwatsuki, K. (2015). Interferon-Gamma Enhances TLR3 Expression and Anti-Viral Activity in Keratinocytes. Journal of Investigative Dermatology, 135(8), 2005-2011. doi:10.1038/jid.2015.125Weihua, X., Kolla, V., & Kalvakolanu, D. V. (1997). Modulation of Interferon Action by Retinoids. Journal of Biological Chemistry, 272(15), 9742-9748. doi:10.1074/jbc.272.15.974

Polyglutamic Acid-Gated Mesoporous Silica Nanoparticles for Enzyme-Controlled Drug Delivery

This document is the Accepted Manuscript version of a Published Work that appeared in final form in Langmuir, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see http://dx.doi.org/10.1021/acs.langmuir.6b01715.Mesoporous silica nanoparticles (MSNs) are highly attractive as supports in the design of controlled delivery systems that can act as containers for the encapsulation of therapeutic agents, overcoming common issues such as poor water solubility and poor stability of some drugs and also enhancing their bioavailability. In this context, we describe herein the development of polyglutamic acid (PGA)-capped MSNs that can selectively deliver rhodamine B and doxorubicin. PGA-capped MSNs remain closed in an aqueous environment, yet they are able to deliver the cargo in the presence of pronase because of the hydrolysis of the peptide bonds in PGA. The prepared solids released less than 20% of the cargo in 1 day in water, whereas they were able to reach 90% of the maximum release of the entrapped guest in ca. 5 h in the presence of pronase. Studies of the PGA-capped nanoparticles with SK-BR-3 breast cancer cells were also undertaken. Rhodamine-loaded nanoparticles were not toxic, whereas doxorubicin-loaded nanoparticles were able to efficiently kill more than 90% of the cancer cells at a concentration of 100 μg/mL.A.T. wishes to express her gratitude to the Erasmus mundus (Svagata.eu) financial support. A.U. and C. de la T. are grateful to the Spanish Ministry of Education, Culture and Sport for her doctoral fellowship. We thank the Spanish Government (Project MAT2015-64139-C4-1-R, MINECO/FEDER) and Generalitat Valenciana (Project PROMETEOII/2014/047) for their support. The authors also thank UPV electron microscopy services for the technical support.Tukappa, A.; Ultimo, A.; De La Torre Paredes, C.; Pardo Vicente, MT.; Sancenón Galarza, F.; Martínez-Máñez, R. (2016). Polyglutamic Acid-Gated Mesoporous Silica Nanoparticles for Enzyme-Controlled Drug Delivery. Langmuir. 32(33):8507-8515. https://doi.org/10.1021/acs.langmuir.6b01715S85078515323

What are microRNAs? Potential biomarkers and therapeutic targets in osteoporosis

Los micro-ARN (miRs) son pequeñas moléculas de ARN no codificantes que regulan la expresión génica a nivel post-transcripcional. Generalmente actúan sobre la expresión genética mediante el silenciamiento o degradación de los ARNm, y están implicados en la regulación de varios procesos biológicos, como la diferenciación celular, la proliferación, la apoptosis y en el desarrollo embrionario y tisular. Actualmente son un importante foco de interés para el estudio de diversas enfermedades como el cáncer o la diabetes mellitus tipo 2. A nivel del metabolismo óseo, están surgiendo diversos miRs implicados en su regulación, abriendo un campo de investigación importante para identificar nuevos biomarcadores para el diagnóstico de la enfermedad osteoporótica, de su evolución, así como para diseñar nuevas terapias farmacológicas.Micro-RNAs (miRs) are small non-coding RNA molecules that regulate gene expression at post-transcriptional level. Generally, they act on gene expression by silencing or degrading mRNAs, and are involved in regulating various biological processes, such as cell differentiation, proliferation, apoptosis and in embryonic and tissue development. They are currently a major focus of interest in the study of various diseases such as cancer or type 2 diabetes mellitus. At level of bone metabolism, various miRs are emerging that are involved in their regulation, opening an important research field to identify new biomarkers for diagnosis of osteoporosis and its development, and to design new drug therapies