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Biology subjects

Sanz-Moreno, V.

Publications and source records attributed to Sanz-Moreno, V..

5 recordsLinked to original sources

LOX inhibition disrupts a collagen-integrin-MYC axis as a translatable targeting strategy in invasive lobular carcinoma

Invasive lobular carcinoma (ILC) accounts for 15% of breast cancers yet lacks specific therapy because ILCs are underrepresented in clinical trials and preclinical models are lacking. We established intraductal xenograft models to test whether the clinical pan-lysyl-oxidase PXS-5505, now in phase trials for myelofibrosis can exploit the collagen-rich matrix dependency created by CDH1 loss. PXS-5505 remodels fibrillar collagen, and halts tumor expansion and metastatic seeding across ER+ and triple negative models without systemic toxicity. Genome-wide CRISPR screens reveal ITGAV and ITGB5 as synthetic lethal partners of CDH1 and LOX inhibition downregulates their expression together with MYC, NF-{kappa}B, and AP-1 transcriptional programmes. Collagen fibre density/alignment, and MYC/AP-1 gene signatures serve as pharmacodynamic readouts of drug activity. These data uncover a tractable ECM-integrin-MYC axis in ILC and nominate PXS-5505, alone or with endocrine therapy, for window of opportunity trials in this understudied breast cancer subtype. One Sentence SummaryTargeting matrix remodelling in ILC inhibits ILC progression and alters multiple molecular endpoints, providing a translatable therapeutic strategy for this understudied subtype that requires better treatments.

cancer biology↗

LAP1 regulates nuclear plasticity to enable constrained migration

Metastasis involves dissemination of cancer cells away from a primary tumour and colonisation at distal sites. During this process, cancer cells must negotiate multiple physical constraints imposed by the microenvironment and tissue structure. The biophysical properties of the nucleus must be tuned since they pose a challenge to constrained migration. By analysing nuclear genes upregulated during the acquisition of metastatic potential, we discovered increased expression of the inner nuclear membrane protein LAP1 in metastatic melanoma cells and at the invasive fronts of human primary tumours and in metastases. Human cells express two LAP1 isoforms (LAP1B and LAP1C), which differ in their amino terminus. We found that whereas the longer isoform, LAP1B, binds more strongly to nuclear lamins and has restricted motility within the nuclear envelope, the shorter isoform, LAP1C, favours nuclear envelope blebbing and allows migration through constraints. We propose that LAP1 renders the nucleus plastic and enhances melanoma aggressiveness.

cell biology↗

Early mismatch between cancer cells and their tumour microenvironment blocks long term growth

Cancer cells thrive embedded in a fine-tuned cellular and extracellular environment or tumour microenvironment (TME). There is a general understanding of a co-evolution between cancer cells and their surrounding TME, pointing at a functional connection between cancer cells characteristics and the perturbations induced in their surrounding tissue. However, whether this functional connection needs to be set from the start or if aggressive cancer cells can always be dominating their microenvironment has never been formally proven with a dedicated experimental setting where malignant cells can be challenged to grow in a different TME from the one they would naturally create. Here we generated an experimental setting where we transiently perturb the secretory profile of aggressive breast cancer cells without affecting their intrinsic growth ability. This led to the initial establishment of an atypical TME. Interestingly, even if initially tumours are formed, this atypical TME evolves to impair long term in vivo cancer growth. Using a combination of in vivo transcriptomics, protein arrays and in vitro co-cultures, we found that the atypical TME culminates in the infiltration of macrophages with STAT1high activity. These macrophages show strong anti-tumoural functions which reduce long-term tumour growth, despite lacking canonical M1 markers. Importantly, gene signatures of the mesenchymal compartment of the TME, as well as the anti-tumoural macrophages show striking prognostic power-correlating with less aggressive human breast cancers.

cancer biology↗

Podoplanin drives dedifferentiation and amoeboid invasion of melanoma

Melanoma is an aggressive skin cancer developing from melanocytes, frequently resulting in metastatic disease. Melanoma cells utilise amoeboid migration as mode of local invasion. Amoeboid invasion is characterized by rounded cell morphology and high actomyosin contractility driven by the RhoA signalling pathway. Migrastatic drugs targeting actin polymerization and contractility to inhibit invasion and metastasis are therefore a promising treatment option. To predict amoeboid invasion and metastatic potential, there is a need for biomarkers functionally linked to contractility pathways. The glycoprotein podoplanin drives actomyosin contractility in lymphoid fibroblasts, and is overexpressed in several cancer types. Here, we show that podoplanin enhances amoeboid invasion in melanoma. Expression of podoplanin in murine melanoma models drives rounded cell morphology, increasing motility and invasion in vivo. Podoplanin expression is upregulated in a subset of dedifferentiated human melanoma, and in vitro is sufficient to suppress melanogenesis and upregulate melanoma-associated markers Mitf and Pou3f2. Together, our data indicates that podoplanin is both a potential biomarker for dedifferentiated invasive melanoma and a promising migrastatic therapeutic target.

cancer biology↗

Cdc42EP5/BORG3 coordinates septin and actin networks to promote actomyosin function and melanoma invasion and metastasis

Fast amoeboid migration in the invasive fronts of melanoma is controlled by high levels of actomyosin contractility, which underlie its highly metastatic potential. How this migratory behaviour is coupled to other cytoskeletal components is poorly understood. Septins are increasingly recognized as novel cytoskeletal components, but details on their regulation and contribution to cancer migration and metastasis are lacking. Here, we show that the septin regulator Cdc42EP5 is consistently required for melanoma cells to migrate and invade into collagen-rich matrices, and to locally invade and disseminate in vivo. Cdc42EP5 associates with actin structures leading to increased actomyosin contractility and amoeboid migration. Cdc42EP5 effects these functions through SEPT9-dependent F-actin crosslinking, which enables the generation of F-actin bundles required for the sustained stabilisation of highly contractile actomyosin structures. This study provides evidence for Cdc42EP5 as a regulator of cancer cell motility that coordinates actin and septin networks. It also describes a unique role for SEPT9 in invasion and metastasis, and illustrates a mechanism that regulates its function in melanoma.

cancer biology↗