Open Access
Proteomic and functional characterisation of extracellular vesicles from collagen VI deficient human fibroblasts reveals a role in cell motility
(Springer, 2023) Badosa, Carmen; Roldán, Mónica; Fernández Irigoyen, Joaquín; Santamaría Martínez, Enrique; Jiménez-Mallebrera, Cecilia; Ciencias de la Salud; Osasun Zientziak
Extracellular vesicles (EVs) are key mediators of cell-to-cell communication. Their content reflects the state of diseased cells representing a window into disease progression. Collagen-VI Related Muscular Dystrophy (COL6-RD) is a multi-systemic disease involving different cell types. The role of EVs in this disease has not been explored. We compared by quantitative proteomics the protein cargo of EVs released from fibroblasts from patients with COL6-RD and controls. Isolated EVs contained a significant proportion of the most frequently reported proteins in EVs according to Exocarta and Vesiclepedia. We identified 67 differentially abundant proteins associated with vesicle transport and exocytosis, actin remodelling and the cytoskeleton, hemostasis and oxidative stress. Treatment of control fibroblasts with EVs from either patient or healthy fibroblasts altered significantly the motility of cells on a cell migration assay highlighting the functional relevance of EVs. In parallel, we analysed the secretome from the same cells and found a distinctly different set of 48 differentially abundant proteins related to extracellular matrix organisation and remodelling, growth factor response, RNA metabolism and the proteasome. The EVs and secretome sets of proteins only shared two identifiers indicating that the sorting of proteins towards EVs or the secretory pathway is tightly regulated for different functions. .
Open Access
PD-1/LAG-3 co-signaling profiling uncovers CBL ubiquitin ligases as key immunotherapy targets
(EMBO Press, 2024-07-19) Chocarro de Erauso, Luisa; Blanco, Ester; Fernández-Rubio, Leticia; Garnica, Maider; Zuazo Ibarra, Miren; García Granda, María Jesús; Bocanegra Gondán, Ana Isabel; Echaide Górriz, Míriam; Johnston, Colette; Edwards, Carolyn J.; Legg, James; Pierce, Andrew J.; Arasanz Esteban, Hugo; Fernández Hinojal, Gonzalo; Vera García, Ruth; Ausín, Karina; Santamaría Martínez, Enrique; Fernández Irigoyen, Joaquín; Kochan, Grazyna; Escors Murugarren, David; Ciencias de la Salud; Osasun Zientziak
Many cancer patients do not benefit from PD-L1/PD-1 blockade immunotherapies. PD-1 and LAG-3 co-upregulation in T-cells is one of the major mechanisms of resistance by establishing a highly dysfunctional state in T-cells. To identify shared features associated to PD-1/LAG-3 dysfunctionality in human cancers and T-cells, multiomic expression profiles were obtained for all TCGA cancers immune infiltrates. A PD-1/LAG-3 dysfunctional signature was found which regulated immune, metabolic, genetic, and epigenetic pathways, but especially a reinforced negative regulation of the TCR signalosome. These results were validated in T-cell lines with constitutively active PD-1, LAG-3 pathways and their combination. A differential analysis of the proteome of PD-1/LAG-3 T-cells showed a specific enrichment in ubiquitin ligases participating in E3 ubiquitination pathways. PD-1/LAG-3 co-blockade inhibited CBL-B expression, while the use of a bispecific drug in clinical development also repressed C-CBL expression, which reverted T-cell dysfunctionality in lung cancer patients resistant to PD-L1/PD-1 blockade. The combination of CBL-B-specific small molecule inhibitors with anti-PD-1/anti-LAG-3 immunotherapies demonstrated notable therapeutic efficacy in models of lung cancer refractory to immunotherapies, overcoming PD-1/LAG-3 mediated resistance. © The Author(s) 2024.
Open Access
The regulators of peroxisomal acyl-carnitine shuttle CROT and CRAT promote metastasis in melanoma
(Elsevier, 2023) Lasheras Otero, Irene; Feliu, Iker; Maíllo Ruiz de Infante, Alberto; Moreno, Haritz; Redondo Muñoz, Marta; Aldaz Donamaría, Paula; Bocanegra Gondán, Ana Isabel; Olías Arjona, Ana; Lecanda, Fernando; Fernández Irigoyen, Joaquín; Santamaría Martínez, Enrique; Larráyoz, Ignacio M.; Gómez-Cabrero, David; Wellbrock, Claudia; Vicent, Silvestre; Arozarena Martinicorena, Imanol; Ciencias; Zientziak; Ciencias de la Salud; Osasun Zientziak
Circulating tumor cells are the key link between a primary tumor and distant metastases, but once in the bloodstream, loss of adhesion induces cell death. To identify the mechanisms relevant for melanoma circulating tumor cell survival, we performed RNA sequencing and discovered that detached melanoma cells and isolated melanoma circulating tumor cells rewire lipid metabolism by upregulating fatty acid (FA) transport and FA betaoxidation‒related genes. In patients with melanoma, high expression of FA transporters and FA beta-oxidation enzymes significantly correlates with reduced progression-free and overall survival. Among the highest expressed regulators in melanoma circulating tumor cells were the carnitine transferases carnitine O-octanoyltransferase and carnitine acetyltransferase, which control the shuttle of peroxisome-derived medium-chain FAs toward mitochondria to fuel mitochondrial FA beta-oxidation. Knockdown of carnitine O-octanoyltransferase or carnitine acetyltransferase and short-term treatment with peroxisomal or mitochondrial FA beta-oxidation inhibitors thioridazine or ranolazine suppressed melanoma metastasis in mice. Carnitine O-octanoyltransferase and carnitine acetyltransferase depletion could be rescued by medium-chain FA supplementation, indicating that the peroxisomal supply of FAs is crucial for the survival of nonadherent melanoma cells. Our study identifies targeting the FA-based cross-talk between peroxisomes and mitochondria as a potential therapeutic opportunity to challenge melanoma progression. Moreover, the discovery of the antimetastatic activity of the Food and Drug Administration‒approved drug ranolazine carries translational potential.
Open Access
ONECUT2 reprograms neuroendocrine fate and is an actionable therapeutic target in small cell lung cancer
(BioMed Central, 2025-06-11) Gutiérrez Núñez, Miriam; Zamora Álvarez, Irene; Iriarte, Raquel; Pajares Villandiego, María Josefa; Yang, Qian; Qian, Chen; Otegui, Nerea; Fernández Irigoyen, Joaquín; Santamaría Martínez, Enrique; Alcala, Nicolas; Sexton-Oates, Alexandra; Fernández-Cuesta, Lynnette; Barajas Vélez, Miguel Ángel; Calvo, Alfonso; Montuenga, Luis M.; Knudsen, Beatrice S.; You, Sungyong; Freeman, Michael R.; Encío Martínez, Ignacio; Rotinen Díaz, Mirja Sofia; Ciencias de la Salud; Osasun Zientziak; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
Small cell lung cancer (SCLC) is a highly aggressive malignancy with extremely poor prognosis. SCLC cells exhibit high plasticity and can progress from neuroendocrine (NE) to non-NE phenotypes. This dynamic evolution promotes treatment resistance and relapses, representing a challenge for targeted therapies in this elusive disease. Here we identify the transcription factor ONECUT2 (OC2) as a driver of plasticity in SCLC, leading to non-NE transcriptional states. OC2 is highly expressed in SCLC tumors compared to normal lung tissue and its expression is associated with heightened clinical stage and lymph node metastasis. We show that OC2 is a repressor of ASCL1, the NE master regulator transcription factor. In addition, OC2 upregulates non-NE programs through activation of c-MYC and Notch signaling. We also demonstrate that OC2 is required for growth and survival of SCLC cells and that it can be targeted with a small molecule inhibitor that acts synergistically with the standard combination of cisplatin and etoposide, providing a novel therapeutic strategy for OC2 active SCLC tumors.
Open Access
RTP801 interacts with the tRNA ligase complex and dysregulates its RNA ligase activity in Alzheimer's disease
(Oxford University Press, 2024-09-12) Campoy-Campos, Genís; Solana-Balaguer, Júlia; Guisado-Corcoll, Anna; Chicote-González, Almudena; García-Segura, Pol; Pérez-Sisqués, Leticia; Gabriel Torres, Adrián; Canal, Mercè; Molina-Porcel, Laura; Fernández Irigoyen, Joaquín; Santamaría Martínez, Enrique; Pouplana, Lluís Ribas de; Alberch, Jordi; Martí, Eulàlia; Giralt, Albert; Pérez-Navarro, Esther; Malagelada, Cristina; Ciencias de la Salud; Osasun Zientziak
RTP801/REDD1 is a stress-responsive protein overexpressed in neurodegenerative diseases such as Alzheimer's disease (AD) that contributes to cognitive deficits and neuroinflammation. Here, we found that RTP801 interacts with HSPC117, DDX1 and CGI-99, three members of the tRNA ligase complex (tRNA-LC), which ligates the excised exons of intron-containing tRNAs and the mRNA exons of the transcription factor XBP1 during the unfolded protein response (UPR). We also found that RTP801 modulates the mRNA ligase activity of the complex in vitro since RTP801 knockdown promoted XBP1 splicing and the expression of its transcriptional target, SEC24D. Conversely, RTP801 overexpression inhibited the splicing of XBP1. Similarly, in human AD postmortem hippocampal samples, where RTP801 is upregulated, we found that XBP1 splicing was dramatically decreased. In the 5xFAD mouse model of AD, silencing RTP801 expression in hippocampal neurons promoted Xbp1 splicing and prevented the accumulation of intron-containing pre-tRNAs. Finally, the tRNA-enriched fraction obtained from 5xFAD mice promoted abnormal dendritic arborization in cultured hippocampal neurons, and RTP801 silencing in the source neurons prevented this phenotype. Altogether, these results show that elevated RTP801 impairs RNA processing in vitro and in vivo in the context of AD and suggest that RTP801 inhibition could be a promising therapeutic approach.
Open Access
Motor skill learning modulates striatal extracellular vesicles' content in a mouse model of Huntington's disease
(BMC, 2024-06-11) Solana-Balaguer, Júlia; García-Segura, Pol; Campoy-Campos, Genís; Chicote-González, Almudena; Fernández Irigoyen, Joaquín; Santamaría Martínez, Enrique; Pérez-Navarro, Esther; Masana, Mercè; Alberch, Jordi; Malagelada, Cristina; Ciencias de la Salud; Osasun Zientziak
Huntington's disease (HD) is a neurological disorder caused by a CAG expansion in the Huntingtin gene (HTT). HD pathology mostly affects striatal medium-sized spiny neurons and results in an altered cortico-striatal function. Recent studies report that motor skill learning, and cortico-striatal stimulation attenuate the neuropathology in HD, resulting in an amelioration of some motor and cognitive functions. During physical training, extracellular vesicles (EVs) are released in many tissues, including the brain, as a potential means for inter-tissue communication. To investigate how motor skill learning, involving acute physical training, modulates EVs crosstalk between cells in the striatum, we trained wild-type (WT) and R6/1 mice, the latter with motor and cognitive deficits, on the accelerating rotarod test, and we isolated their striatal EVs. EVs from R6/1 mice presented alterations in the small exosome population when compared to WT. Proteomic analyses revealed that striatal R6/1 EVs recapitulated signaling and energy deficiencies present in HD. Motor skill learning in R6/1 mice restored the amount of EVs and their protein content in comparison to naïve R6/1 mice. Furthermore, motor skill learning modulated crucial pathways in metabolism and neurodegeneration. All these data provide new insights into the pathogenesis of HD and put striatal EVs in the spotlight to understand the signaling and metabolic alterations in neurodegenerative diseases. Moreover, our results suggest that motor learning is a crucial modulator of cell-to-cell communication in the striatum.
Open Access
Signature-driven repurposing of Midostaurin for combination with MEK1/2 and KRASG12C inhibitors in lung cancer
(Springer Nature, 2023) Macaya, Irati; Roman, Marta; Welch, Connor; Entrialgo-Cadierno, Rodrigo; Salmon, Marina; Santos, Alba; Feliu, Iker; Kovalski, Joanna; López Erdozain, Inés; Rodríguez-Remírez, María; Palomino Echeverría, Sara; Lonfgren, Shane M.; Ferrero, Macarena; Calabuig, Silvia; Ludwig, Iziar A.; Lara-Astiaso, David; Jantus-Lewintre, Eloisa; Guruceaga, Elizabeth; Narayanan, Shruthi; Ponz Sarvisé, Mariano; Pineda Lucena, Antonio; Lecanda, Fernando; Ruggero, Davide; Khatri, Purvesh; Santamaría Martínez, Enrique; Fernández Irigoyen, Joaquín; Ferrer, Irene; Paz-Ares, Luis; Drosten, Matthias; Barbacid, Mariano; Gil-Bazo, Ignacio; Vicent, Silvestre; Ciencias de la Salud; Osasun Zientziak
Drug combinations are key to circumvent resistance mechanisms compromising response to single anti-cancer targeted therapies. The implementation of combinatorial approaches involving MEK1/2 or KRASG12C inhibitors in the context of KRAS-mutated lung cancers focuses fundamentally on targeting KRAS proximal activators or effectors. However, the antitumor effect is highly determined by compensatory mechanisms arising in defined cell types or tumor subgroups. A potential strategy to find drug combinations targeting a larger fraction of KRAS-mutated lung cancers may capitalize on the common, distal gene expression output elicited by oncogenic KRAS. By integrating a signature-driven drug repurposing approach with a pairwise pharmacological screen, here we show synergistic drug combinations consisting of multi-tyrosine kinase PKC inhibitors together with MEK1/2 or KRASG12C inhibitors. Such combinations elicit a cytotoxic response in both in vitro and in vivo models, which in part involves inhibition of the PKC inhibitor target AURKB. Proteome profiling links dysregulation of MYC expression to the effect of both PKC inhibitor-based drug combinations. Furthermore, MYC overexpression appears as a resistance mechanism to MEK1/2 and KRASG12C inhibitors. Our study provides a rational framework for selecting drugs entering combinatorial strategies and unveils MEK1/2- and KRASG12C-based therapies for lung cancer.
Open Access
Docosahexaenoic acid ameliorates contextual fear memory deficits in the Tg2576 Alzheimer´s disease mouse model: cellular and molecular correlates
(MDPI, 2023) Badesso, Sara; Cartas Cejudo, Paz; Espelosín, María; Santamaría Martínez, Enrique; Cuadrado-Tejedor, Mar; García-Osta, Ana; Ciencias de la Salud; Osasun Zientziak
Docosahexaenoic acid (DHA), the most abundant polyunsaturated fatty acid in the brain, is essential for successful aging. In fact, epidemiological studies have demonstrated that increased intake of DHA might lower the risk for developing Alzheimer’s disease (AD). These observations are supported by studies in animal models showing that DHA reduces synaptic pathology and memory deficits. Different mechanisms to explain these beneficial effects have been proposed; however, the molecular pathways involved are still unknown. In this study, to unravel the main underlying molecular mechanisms activated upon DHA treatment, the effect of a high dose of DHA on cognitive function and AD pathology was analyzed in aged Tg2576 mice and their wild-type littermates. Transcriptomic analysis of mice hippocampi using RNA sequencing was subsequently performed. Our results revealed that, through an amyloid-independent mechanism, DHA enhanced memory function and increased synapse formation only in the Tg2576 mice. Likewise, the IPA analysis demonstrated that essential neuronal functions related to synaptogenesis, neuritogenesis, the branching of neurites, the density of dendritic spines and the outgrowth of axons were upregulated upon-DHA treatment in Tg2576 mice. Our results suggest that memory function in APP mice is influenced by DHA intake; therefore, a high dose of daily DHA should be tested as a dietary supplement for AD dementia prevention.
Open Access
Amyloid-driven tau accumulation on mitochondria potentially leads to cognitive deterioration in Alzheimer’s disease
(MDPI, 2021) Cuadrado-Tejedor, Mar; Pérez-González, Marta; Alfaro-Ruiz, Rocío; Badesso, Sara; Sucunza, Diego; Espelosín, María; Ursúa, Susana; Lachén Montes, Mercedes; Fernández Irigoyen, Joaquín; Santamaría Martínez, Enrique; Luján, Rafael; García-Osta, Ana; Ciencias de la Salud; Osasun Zientziak; Gobierno de Navarra / Nafarroako Gobernua
Despite the well-accepted role of the two main neuropathological markers (β-amyloid and tau) in the progression of Alzheimer’s disease, the interaction and specific contribution of each of them is not fully elucidated. To address this question, in the present study, an adeno-associated virus (AAV9) carrying the mutant P301L form of human tau, was injected into the dorsal hippocampi of APP/PS1 transgenic mice or wild type mice (WT). Three months after injections, memory tasks, biochemical and immunohistochemical analysis were performed. We found that the overexpression of hTauP301L accelerates memory deficits in APP/PS1 mice, but it did not affect memory function of WT mice. Likewise, biochemical assays showed that only in the case of APP/PS1-hTauP301L injected mice, an important accumulation of tau was observed in the insoluble urea fraction. Similarly, electron microscopy images revealed that numerous clusters of tau immunoparticles appear at the dendrites of APP/PS1 injected mice and not in WT animals, suggesting that the presence of amyloid is necessary to induce tau aggregation. Interestingly, these tau immunoparticles accumulate in dendritic mitochondria in the APP/PS1 mice, whereas most of mitochondria in WT injected mice remain free of tau immunoparticles. Taken together, it seems that amyloid induces tau aggregation and accumulation in the dendritic mitochondria and subsequently may alter synapse function, thus, contributing to accelerate cognitive decline in APP/PS1 mice.
Open Access
Influence of short-term training on functional capacity and (anti-)inflammatory immune signalling in acute hospitalization
(Wiley, 2020) Ramírez Vélez, Robinson; Martínez Velilla, Nicolás; Fernández Irigoyen, Joaquín; Santamaría Martínez, Enrique; Izquierdo Redín, Mikel; Palomino Echeverría, Sara; Ciencias de la Salud; Osasun Zientziak; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa; Gobierno de Navarra / Nafarroako Gobernua
To investigate the infuence of exercise on inflammatory signalling, it was performed cytokine array profiling in human serum to identify inflammatory cytokines produced after a 3 day in-hospital intervention including individualized moderate-intensity resistance, balance, and walking exercises vs. medical usual-care for acute hospitalization in very elderly patients.