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Carrasco, G.

Publications and source records attributed to Carrasco, G..

3 recordsLinked to original sources

Kindlin-1 loss disrupts vascular and extracellular matrix organisation to sustain hypoxia in cutaneous squamous cell carcinoma

Kindlin-1, encoded by FERMT1, is an essential integrin co-activator that regulates cell-extracellular matrix (ECM) adhesion, tissue architecture, and microenvironment signalling. Loss-of-function mutations in FERMT1 cause Kindler epidermolysis bullosa, which is strongly associated with aggressive cutaneous squamous cell carcinoma (cSCC). Although Kindlin-1 deficiency promotes hypoxia and invasion, the impacts on ECM-vascular organisation and oxygen homeostasis are not known. Here, using genetic deletion of Kindlin-1 in a murine model of cSCC across 2D cultures, 3D spheroids, and in vivo tumours, combined with collagen and vascular imaging and spatial mixed-effects modelling, we show that Kindlin-1 loss uncouples ECM-vascular regulation, driving hypoxia and tumour progression. Tumours in which Kindlin-1 was deleted displayed a dense but dysfunctional vascular network, with reduced tissue-to-vessel and inter-bifurcation distances, increased vessel alignment, and persistent hypoxia despite increased vascular density. Collagen deposition was reduced and fibres were straighter, indicating a simplified, invasion-permissive matrix. Hypoxia increased Vegfa and Angpt1 expression while reducing Col1a1, and hypoxia-responsive spheroids confirmed greater hypoxia and invasiveness in Kindlin-1-deficient cells. Transcriptomic analysis revealed enrichment of ECM degradation and vascular dysfunction pathways, including upregulation of matrix-remodelling and vascular permeability genes such as Mmp13, Mmp3, and Ptgs2, alongside reduced collagen-associated and vascular homeostasis genes. Spatial modelling further showed disrupted collagen-vascular coupling and an association between hypoxia and reduced vessel diameter, consistent with dysfunctional angiogenesis rather than improved perfusion. These changes arose early and independently of tumour size, establishing impaired integrin activation as a central mechanism linking ECM degradation, vascular dysfunction, and sustained hypoxia in aggressive cSCC.

cancer biology↗

FAK inhibitor treatment systemically regulates the glioblastoma immune environment via blocking monocyte trafficking

Glioblastoma (GBM) is the most common primary malignant brain tumour in adults with dismal survival rates, and current therapies, including most immunotherapies, are not efficacious due to the highly immunosuppressive microenvironment. Studies in other solid cancers report that impairment of the integrin effector pathway involving focal adhesion kinase (FAK) can promote anti-tumour immune responses. Therefore, we set out to address whether, and if so how, suppressing FAK function may influence GBM by using both tumour cell-specific FAK gene deletion and systemic delivery of a clinically relevant FAK kinase inhibitor (FAKi) VS-4718 in an orthotopic murine stem cell model of GBM. We found that treatment with the FAKi, but not tumour cell-specific FAK gene deletion, resulted in GBM clearance and improved survival. This was dependent on adaptive immunity, and tumour-infiltrating T cells in FAKi-treated tumours displayed increased cytotoxic potential and reduced exhaustion. We also found a significant reduction in immuno-suppressive peripherally-derived macrophages and FAKi treatment caused sequestration of inflammatory monocytes within the bone marrow, resulting in impaired monocyte trafficking to tumours as judged by adoptive transfer. This is due to suppression of key adhesion and migration signalling through 4{beta}1 integrin and CX3CR1 in peripheral monocytes. Our work here describes a previously unidentified role for FAK in trafficking of peripheral suppressive macrophages to GBM tumours, reducing T cell exhaustion and promoting anti-tumour immunity. This highlights a new way in which systemic FAK inhibitors can be used to provide a beneficial immune modulatory strategy for the treatment of GBM.

immunology↗

Life on the edge: microbial diversity, resistome, and virulome in soils from the Union Glacier cold desert

The high-latitude regions of Antarctica remain among the most remote, extreme, and least explored areas on Earth. Despite the highly restrictive conditions, microbial life has been found in these environments, although with limited information on their genetic properties and functional capabilities. Moreover, the accelerated melting of the Antarctic permafrost, the increasing exposure of soils, and the growing human transit pose the question of whether these environments could be a source of microbes or genes that could emerge and cause global health problems. In this line, although a high bacterial diversity and autochthonous multidrug-resistant bacteria have been found in soils of the Antarctic Peninsula, we still lack information regarding the resistome of areas closer to the South Pole. Moreover, no previous studies have evaluated the pathogenic potential of microbes inhabiting Antarctic soils. In this work, we combined metagenomic and culture-dependent approaches to investigate the microbial diversity, resistome, virulome, and mobile genetic elements (MGEs) in soils from Union Glacier, a high-latitude cold desert in West Antarctica. Despite the low organic matter content, diverse bacterial lineages were found, predominating Actinomycetota and Pseudomonadota, with limited archaeal and fungal taxa. We recovered more than 80 species-level representative genomes (SRGs) of predominant bacterial taxa and the archaeon Nitrosocosmicus sp. Diverse putative resistance and virulence genes were predicted among the SRGs, metagenomic reads, and contigs. Furthermore, we characterized bacterial isolates resistant to up to 24 clinical antibiotics, mainly Pseudomonas, Arthrobacter, Plantibacter, and Flavobacterium. Moreover, some isolates produced putative virulence factors, including siderophores, pyocyanins, and exoenzymes with hemolytic, lecithinase, protease, and DNAse activity. This evidence uncovers a largely unexplored resistome and virulome hosted by deep Antarcticas soil microbial communities and the presence of bacteria with pathogenic potential, highlighting the relevance of One Health approaches for environmental surveillance in the white continent. HIGHLIGHTS-Union Glacier soils host a microbial community dominated by bacteria, mainly from the phylum Actinomycetota. -Archaea from the Nitrosocosmicus genus (family Nitrosphaeraceae) were ubiquitously detected. -Although extreme and remote, these soils host multidrug-resistant and potentially pathogenic bacteria. Some were cultured and tested in vitro. -Metagenomes and species-level representative genomes revealed diverse putative resistance and virulence genes. -Part of the putative antimicrobial resistance genes and virulence factors could be associated with mobile elements in bacterial genomes.

microbiology↗