Metabolic genes in hepatocellular carcinoma developement

Tesis doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Biología Molecular. Fecha de lectura: 08-09-2016Esta tesis tiene embargado el acceso al texto completo hasta el 09-09-2018Hepatocellular carcinoma (HCC) is the second leading cause of death for cancer worldwide. Several studies on hepatocellular carcinoma epidemiology linked this malignancy with obesity and metabolic disorders. However, little is known about the molecular mechanisms responsible for this connection. The main purpose of this thesis is to elucidate the role of Jnk1 and Ppara, two important metabolic genes, in hepatocellular carcinoma development. Adipose tissue is the most important organ for lipid storage; during obesity it undergoes to a substantial remodeling. JNK1 is known to control IL-6 production in the adipose tissue during obesity and its depletion in adipocyte protects against liver steatosis, a predisposing factor for HCC development. We demonstrate that adipose tissue JNK1 in normal diet can trigger hepatocellular carcinoma development. In fact, the deletion of JNK1 in adipose tissue increases circulating levels of adiponectin, which in turn activates AMPKα and p38α in hepatocytes, protecting against chemical-induced tumor development. Our results highlight the relevance of adipose tissue in liver cancer development and the central role that JNK1 plays in this crosstalk. PPARα is a nuclear receptor of fatty acids. It is highly expressed in the liver and obesity induces its activation. However, PPARα role in liver carcinogenesis is controversial. Here we show that PPARα activation promotes obesity-associated hepatic cancer. Mice lacking PPARα are protected against chemical-induced hepatocellular carcinoma when fed a high fat diet. Additionally, bone marrow transplantation experiments reveal no significant contribution of inflammatory cells, suggesting a cell-autonomous function of PPARα in hepatocytes. Hepatic PPARα activation, induced by Jnk1 and Jnk2 deletion, is sufficient to cause spontaneous liver cancer, confirming a central role of PPARα activation in liver tumorigenesis. Our results provide a molecular mechanism linking metabolic disorders with liver cancer, emphasizing a central role for PPARα in the connectionThe support received from the following Grants and Fellowships has permitted to develop this PhD work: La Caixa International PhD Fellowship Program, 2010 Cal

JNK-mediated disruption of bile acid homeostasis promotes intrahepatic cholangiocarcinoma

Metabolic stress causes activation of the cJun NH2-terminal kinase (JNK) signal transduction pathway. It is established that one consequence of JNK activation is the development of insulin resistance and hepatic steatosis through inhibition of the transcription factor PPARalpha. Indeed, JNK1/2 deficiency in hepatocytes protects against the development of steatosis, suggesting that JNK inhibition represents a possible treatment for this disease. However, the long-term consequences of JNK inhibition have not been evaluated. Here we demonstrate that hepatic JNK controls bile acid production. We found that hepatic JNK deficiency alters cholesterol metabolism and bile acid synthesis, conjugation, and transport, resulting in cholestasis, increased cholangiocyte proliferation, and intrahepatic cholangiocarcinoma. Gene ablation studies confirmed that PPARalpha mediated these effects of JNK in hepatocytes. This analysis highlights potential consequences of long-term use of JNK inhibitors for the treatment of metabolic syndrome

Sexual and Reproductive Health and Education of Adolescents during COVID-19 Pandemic, Results from “Come Te La Passi?”—Survey in Bologna, Italy

Social distancing measures adopted to face the COVID-19 pandemic had a detrimental impact on adolescent education and their interaction with peers and adults, secondary to the limitation of school and recreational activities, with repercussions on social and sexual life. The “Come te la passi?” (“How is it going?”) study, performed in the Metropolitan City of Bologna (Italy), aimed at investigating the type of information sources adopted by adolescents for their sexual and reproductive health (SRH) knowledge and education, the age of their sexual debut, and the way in which the COVID-19 pandemic affected their relationships and sexual life in order to help local health care professionals and educators designing SRH education programs. A purposely designed online survey was administered during the COVID-19 pandemic to 378 high school students (age > 14 yo) in July 2021. Based on the study results, the most common source of SRH education was the web, followed by peers (friends). A total of 61.3% of 17-year-olds already had sexual intercourse, and 90% of 15-year-olds had experienced romantic or sexual attraction. For 58.2% of the adolescents, the COVID-19 pandemic had negative effects on their relationships/sexual life. The current research emphasizes the need to involve health care professionals and educators in structured programs to promote SRH education tailored to adolescents’ needs and started from early ages

Eukaryotic elongation factor 2 controls TNF-alpha translation in LPS-induced hepatitis

Bacterial LPS (endotoxin) has been implicated in the pathogenesis of acute liver disease through its induction of the proinflammatory cytokine TNF-alpha. TNF-alpha is a key determinant of the outcome in a well-established mouse model of acute liver failure during septic shock. One possible mechanism for regulating TNF-alpha expression is through the control of protein elongation during translation, which would allow rapid cell adaptation to physiological changes. However, the regulation of translational elongation is poorly understood. We found that expression of p38gamma/delta MAPK proteins is required for the elongation of nascent TNF-alpha protein in macrophages. The MKK3/6-p38gamma/delta pathway mediated an inhibitory phosphorylation of eukaryotic elongation factor 2 (eEF2) kinase, which in turn promoted eEF2 activation (dephosphorylation) and subsequent TNF-alpha elongation. These results identify a new signaling pathway that regulates TNF-alpha production in LPS-induced liver damage and suggest potential cell-specific therapeutic targets for liver diseases in which TNF-alpha production is involved

Adiponectin accounts for gender differences in hepatocellular carcinoma incidence

Hepatocellular carcinoma (HCC) is the sixth most common cancer type and the fourth leading cause of cancer-related death. This cancer appears with higher incidence in men and during obesity; however, the specific mechanisms underlying this correlation are unknown. Adipose tissue, a key organ in metabolic syndrome, shows evident gender disparities in the production of adipokines. Levels of the important adipokine adiponectin decrease in men during puberty, as well as in the obese state. Here, we show that this decrease in adiponectin levels is responsible for the increased liver cancer risk in males. We found that testosterone activates the protein JNK in mouse and human adipocytes. JNK-mediated inhibition of adiponectin secretion increases liver cancer cell proliferation, since adiponectin protects against liver cancer development through the activation of AMP-activated protein kinase (AMPK) and p38α. This study provides insight into adipose tissue to liver crosstalk and its gender relation during cancer development, having the potential to guide strategies for new cancer therapeutics.G. Sabio is an investigator on the Ramón y Cajal Program. E. Manieri is a La Caixa Foundation fellow. L. Herrera-Melle is a fellow of the Ministerio de Educación, Cultura y Deporte (FPU15-05802). This study was funded by the following grants: G. Sabio was funded by the European Research Council (ERC 260464), European Foundation for the Study of Diabetes–Lilly, Ministerio de Ciencia, Innovación y Universidades (MICINN/SAF2016-79126-R), Comunidad de Madrid (B2017/BMD-3733), and BBVA Becas Leonardo a Investigadores y Creadores Culturales (Investigadores-BBVA-2017; IN[17]_BBM_BAS_0066); M. Marcos was funded by Instituto de Salud Carlos III and Federación Española de Enfermedades Raras (PI16/01548); and J.L. Torres was funded by Junta de Castilla y León GRS (1587/A/17). F.J. Cubero is a Ramón y Cajal Researcher (RYC-2014-15242) and a Gilead Liver Research Scholar 2018, and his work is supported by the Ministerio de Economia y Competitividad Retos (SAF2016-78711), Comunidad de Madrid (S2017/BMD-3727), The Alan Morement Memorial Fund Cholangiocarcinoma Charity (2018/117), the European Cooperation in Science and Technology Action (CA17112), and the European Foundation for Alcohol Research (EA14/18). L. Moran is a Comunidad de Madrid fellow (S2017/BMD-3727). The CNIC is supported by the Ministerio de Ciencia, Innovación y Universidades and the Pro CNIC Foundation, and is a Severo Ochoa Center of Excellence (SEV-2015-0505).S

MKK6 deficiency promotes cardiac dysfunction through MKK3-p38γ/δ-mTOR hyperactivation.

Stress-activated p38 kinases control a plethora of functions, and their dysregulation has been linked to the development of steatosis, obesity, immune disorders, and cancer. Therefore, they have been identified as potential targets for novel therapeutic strategies. There are four p38 family members (p38α, p38β, p38γ, and p38δ) that are activated by MKK3 and MKK6. Here, we demonstrate that lack of MKK6 reduces the lifespan in mice. Longitudinal study of cardiac function in MKK6 KO mice showed that young mice develop cardiac hypertrophy which progresses to cardiac dilatation and fibrosis with age. Mechanistically, lack of MKK6 blunts p38α activation while causing MKK3-p38γ/δ hyperphosphorylation and increased mammalian target of rapamycin (mTOR) signaling, resulting in cardiac hypertrophy. Cardiac hypertrophy in MKK6 KO mice is reverted by knocking out either p38γ or p38δ or by inhibiting the mTOR pathway with rapamycin. In conclusion, we have identified a key role for the MKK3/6-p38γ/δ pathway in the development of cardiac hypertrophy, which has important implications for the clinical use of p38α inhibitors in the long-term treatment since they might result in cardiotoxicity.We thank S Bartlett and F Chanut for English editing. We are grateful to RJ Davis, A Padmanabhan, M Costa and C López-Otín for critical reading of the manuscript. We thank Dr. RJ Davis for the MKK3 and MKK6 KO animals and Dr. Erwin F Wagner for the p38α flox mice. We thank AC Silva (ana@anasilva illustrations.com) for help with figure editing and design. This work was funded by a CNIC Intramural Project Severo Ochoa (Expediente 12–2016 IGP) to GS and JJ and PID2019-104399RB-I00 funded by MCIN/AEI/10.13039/501100011033 to GS. BGT was a fellow of FPI Severo Ochoa CNIC Program (SVP-2013-067639) and is an American Heart Association Postdoctoral Fellow (18POST34080175). RRB is a fellow of the FPU Program (FPU17/03847). The following grants provided additional funding: GS is granted by funds from European Regional Development Fund (ERDF): EFSD/Lilly European Diabetes Research Programme Dr Sabio, Fundación AECC PROYE19047SABI and Comunidad de Madrid IMMUNOTHERCAN-CM B2017/BMD-3733; US National Heart, Lung, and Blood Institute (R01 Grant HL122352), Fondos FEDER, Madrid, Spain, and Fundación Bancaria “La Caixa (project HR19/52160013); Fundación La Marató TV3: Ayudas a la investigación en enfermedades raras 2020 (LA MARATO-2020); and Instituto de Salud Carlos III to JJ. IN was funded by EFSD/Lilly grants (2017 and 2019), the CNIC IPP FP7 Marie Curie Programme (PCOFUND-2012–600396), EFSD Rising Star award (2019), JDC-2018-Incorporación (MIN/JDC1802). The CNIC is supported by the Instituto de Salud Carlos III (ISCIII), the Ministerio de Ciencia e Innovación (MCIN) and the Pro CNIC FoundationS

MKK6 controls T3-mediated browning of white adipose tissue

El aumento de la capacidad termogénica del tejido adiposo para mejorar el gasto de energía del organismo se considera una estrategia terapéutica prometedora para combatir la obesidad. Aquí nosotros informe que la expresión del activador MAPK p38 MKK6 está elevada en el tejido adiposo blanco de individuos obesos. Usando animales knockout y shRNA, mostramos que la eliminación de Mkk6 aumenta el gasto de energía y la capacidad termogénica del tejido adiposo blanco, protegiendo a los ratones contra la obesidad inducida por la dieta y el desarrollo de la diabetes. La eliminación de Mkk6 aumenta la expresión de UCP1 estimulada por T3 en los adipocitos, lo que aumenta su capacidad termogénica. De manera mecánica, demostramos que, en el tejido adiposo blanco, p38 se activa mediante una ruta alternativa que involucra AMPK, TAK y TAB. Nuestros resultados identifican MKK6 en los adipocitos como un posible objetivo terapéutico para reducir la obesidad.Increasing the thermogenic capacity of adipose tissue to enhance organismal energy expenditure is considered a promising therapeutic strategy to combat obesity. Here, we report that expression of the p38 MAPK activator MKK6 is elevated in white adipose tissue of obese individuals. Using knockout animals and shRNA, we show that Mkk6 deletion increases energy expenditure and thermogenic capacity of white adipose tissue, protecting mice against diet-induced obesity and the development of diabetes. Deletion of Mkk6 increases T3-stimulated UCP1 expression in adipocytes, thereby increasing their thermogenic capacity. Mechanistically, we demonstrate that, in white adipose tissue, p38 is activated by an alternative pathway involving AMPK, TAK, and TAB. Our results identify MKK6 in adipocytes as a potential therapeutic target to reduce obesity.• Guadalupe Sabio Buzo y Rebeca Acin Pérez pertenecen a Programa Ramón y Cajal • Elisa Manieri pertenece a Caixa • Ministerio de Economía y Competitividad. Proyecto FPI BES-2014-069332, para Valle Montalvo Romeral • Ministerio de Economía y Competitividad. Proyecto FPI BES-2011-043428, para Edgar Bernardo • Ministerio de Economía y Competitividad y FEDER SAF2016-79126-R y Comunidad de Madrid S2010 / BMD-2326, para Guadalupe Sabio Buzo • ISCIII y FEDER, PI10 / 01692 e I3SNS-INT12 / 049, para Miguel Marcos Martín • Junta de Castilla y León GRS 681 / A / 11, para Lourdes Hernández Cosido • Ministerio de Economía y Competitividad. BFU2015-70664-R, Xunta de Galicia 2015-CP080 y PIE13 / 00024, y ERC281408, para Rubén Nogueiras Pozo • Unión Europea. Becas europeas UE0 / MCA1108 y UE0 / MCA1201; y la Comunidad de Madrid CAM / API1009, para Rubén Nogueiras Pozo • Junta de Extremadura y FEDER BR15164, para Francisco Centeno Velázquez • Ministerio de Economía y Competitividad. . BFU2013-46109-R, para Clara V. Álvarez Villamarín • European Union’s Seventh Framework Programme (FP7/2007-2013) under grant agreement no. ERC 260464peerReviewe

p38γ is essential for cell cycle progression and liver tumorigenesis

The cell cycle is a tightly regulated process that is controlled by the conserved cyclin-dependent kinase (CDK)–cyclin protein complex1. However, control of the G0-to-G1 transition is not completely understood. Here we demonstrate that p38 MAPK gamma (p38γ) acts as a CDK-like kinase and thus cooperates with CDKs, regulating entry into the cell cycle. p38γ shares high sequence homology, inhibition sensitivity and substrate specificity with CDK family members. In mouse hepatocytes, p38γ induces proliferation after partial hepatectomy by promoting the phosphorylation of retinoblastoma tumour suppressor protein at known CDK target residues. Lack of p38γ or treatment with the p38γ inhibitor pirfenidone protects against the chemically induced formation of liver tumours. Furthermore, biopsies of human hepatocellular carcinoma show high expression of p38γ, suggesting that p38γ could be a therapeutic target in the treatment of this disease

Sfida all’innovazione e alle pratiche di formazione nella chirurgia robotica. Il caso Toscana

In questa tesi sono stati studiati i meccanismi alla base dell’apprendimento della pratica robotica in chirurgia nel contesto toscano. Dopo aver definito il framework teorico e le metodologie di ricerca, lo studio prende in esame l’indagine quantitativa che si configura come intervento di esplorare opinioni ed esperienze sulle pratiche di formazione nella chirurgia robotica in Toscana con focus sulla dimensione dei bisogni individuali e di pratiche formative, che vanno ad incidere e a loro volta sono influenzate, in un processo circolare, dalla formazione ricevuta o dal ripensamento della stessa. L’analisi qualitativa condotta studia invece il rapporto tra chirurghi, tecnologia e loro percezioni delle evidenze scientifiche. Il processo metodologico utilizzato per condurre la ricerca, ovvero le linee guida della Grounded Theory, è finalizzato a capire “cosa accade in un contesto formativo chirurgico che usa come pratica di lavoro il robot”. Il presente lavoro affronta due temi connettendoli tra loro. Il primo esplorare opinioni e esperienze sulle pratiche di formazione dei formandi in chirurgia robotica in Toscana, con focus sulla dimensione dei bisogni individuali e di pratiche formative. Il secondo le dinamiche che caratterizzano l’apprendimento di una innovazione in un contesto lavorativo quale la chirurgia robotica in Toscana.In this thesis have been studied the mechanisms underlying the learning of the robotic practice in surgery in the Tuscan context. After defining the theoretical framework and research methodologies, the study examines the quantitative survey that is configured as an intervention to explore opinions and experiences on training practices in robotic surgery in Tuscany with a focus on the dimension of individual needs and practices training, which affect and in turn are influenced, in a circular process, by the training received or by rethinking it. The qualitative analysis conducted instead studies the relationship between surgeons, technology and their perceptions of scientific evidence. The methodological process used to conduct the research, the Grounded Theory, is aimed at understanding "what happens in a surgical training context that uses the robot as a work practice". This work deals with two themes by connecting them to each other. The first explores opinions and experiences on the training practices of robotic surgery trainees in Tuscany, with a focus on the dimension of individual needs and training practices. The second is the dynamics that characterize the learning of an innovation in a working context such as robotic surgery in Tuscany