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Biology subjects

Lauria, A.

Publications and source records attributed to Lauria, A..

7 recordsLinked to original sources

TGF-beta dynamically controls epithelial identity in a 3D model of human epiblast

Pluripotency is the ability to give rise to all cell types of the body and is first observed in a mass of disorganised cells of the embryo. Upon implantation, pluripotent cells form a columnar epithelium and undergo lumenogenesis. At gastrulation, a portion of the pluripotent epiblast will undergo epithelial to mesenchymal transition (EMT), forming the primitive streak (PS). It still remains unclear what molecular mechanism supports the epithelial identity of the pluripotent epiblast before gastrulation. Here we developed an optimised, chemically defined 3D model of human pluripotent epiblast formation in which conventional pluripotent stem cells (PSCs) self-organise into a columnar epithelium with a lumen in 48 hours. From 72 hours we observed spontaneous symmetry breaking and specification of PS-like cells, as confirmed by single-cell RNA sequencing. We found that Insulin and FGF signalling are both required for the proliferation and survival of the pluripotent epiblast model. Conversely, TGF-beta signalling maintains epithelial identity. Epithelial identity appears uncoupled from the expression of canonical pluripotency markers OCT4, NANOG and PRDM14, but under the control of ZNF398. Once the pluripotent epithelium is established, TGF-beta inhibition is inconsequential, and stimulation with Activin A leads to highly efficient PS induction. We conclude that TGF-beta dynamically orchestrates epithelial identity of human pluripotent cells.

developmental biology↗

FVIII interacts with cell surface to regulate endothelial cell functionality

Haemophilia A (HA) is a rare bleeding disorder caused by factor 8 (F8) mutations. Clinical manifestations are spontaneous bleedings that primarily consist of hemarthrosis and intracranial haemorrhages. To date, the impairment of vessel stability in HA patients and the correlation between FVIII and endothelial functionality is poorly understood. Here we show that FVIII plays a role in endothelial cell functionality. Blood Outgrowth endothelial cells (BOECs) knockout generated by CRISPR/Cas9, HA BOECs and HA iPSCs-derived ECs showed alteration of vessel-formation, endothelial cell migration, and vessel permeability. Importantly, the impaired EC phenotype was rescued by treatment with recombinant human FVIII or by lentiviral vector (LV) expressing FVIII. The FVIII function on endothelium was confirmed in vivo in a mouse model of severe HA which showed that an altered angiogenesis and vesselpermeability could be treated by exogenous FVIII. BOECstranscriptomic profiles revealed that FVIIIregulates the expression of endothelial basement membrane and extracellular matrix genes. Furthermore, exogenous expression of Nidogen2, identified as a FVIII regulated gene, restored the extracellular matrix integrity and EC functionality of HA ECs. In conclusion, FVIII is not only a coagulation factor but also an endothelial cell autocrine factor which promotes vessel stability.

molecular biology↗

TGF-β induces matrisome pathological alterations and EMT in patient-derived prostate cancer tumoroids

Extracellular matrix (ECM) tumorigenic alterations resulting in high matrix deposition and stiffening are hallmarks of adenocarcinomas and are collectively defined as desmoplasia. Here, we thoroughly analysed primary prostate cancer tissues obtained from numerous patients undergoing radical prostatectomy to highlight reproducible structural changes in the ECM leading to the loss of the glandular architecture. Starting from patient cells, we established prostate cancer tumoroids (PCTs) and demonstrated they require TGF-{beta} signalling pathway activity to preserve phenotypical and structural similarities with the tissue of origin. By modulating TGF-{beta} signalling pathway in PCTs, we unveiled its role in ECM accumulation and remodelling in prostate cancer. We also found that TGF-{beta}-induced ECM remodelling is responsible for the initiation of prostate cell epithelial-to-mesenchymal transition (EMT) and the acquisition of a migratory, invasive phenotype. Our findings highlight the cooperative role of TGF-{beta} signalling and ECM desmoplasia in prompting prostate cell EMT and promoting tumour progression and dissemination

cancer biology↗

Lifelong tissue memory relies on spatially organised dedicated progenitors located distally from the injury

It is believed epithelial cells that have participated in a wound repair elicit a more efficient but locally restricted response to future injuries. However here we show that the cell adaptation resulting from a localised tissue damage has a wide spatial impact at a scale not previously noticed. We demonstrate that away from injured site, after a first injury a specific epithelial stem cell population gives rise to long term wound-memory progenitors residing in their own niche of origin. Notably these progenitors have not taken part in the first wound healing but become pre-activated through priming. This adaptation differs from classical features of trained immunity previously shown to be adopted by other epithelial stem cells. Our newly identified wound-distal memory cells display a cell-autonomous transcriptional pre-activated state leading to an enhanced wound repair ability that can be partially recapitulated through epigenetic perturbation even in absence of an injury. Importantly, the harmful consequences of wound repair, such as exacerbated tumorigenesis, occur within these primed cells and follow their spatial distribution. Overall, we show that sub-organ scale adaptation of an injury relies on spatially organised and memory-dedicated progenitors, characterised by an epigenetic actionable cell state, that predisposes to tumour onset.

cell biology↗

RNABSdb and 3plex enable deep computational investigation of triplex forming lncRNAs

1.Long non-coding RNAs (lncRNAs) regulate gene expression through different molecular mechanisms, including DNA binding. We curated the first database of RNA Binding Sites (RNABSdb) by harmonising publicly available raw-data of RNA-DNA binding experiments. This resource is crucial to enable systematic studies on transcriptional regulation driven by lncRNAs. Focusing on high quality experiments, we find that the number of binding sites for each lncRNAs varies from hundreds to tens of thousands. Despite being poorly characterised, the formation of RNA:DNA:DNA triple helices (TPXs) is one of the molecular mechanisms that allows lncRNAs to bind the genome and regulate gene expression. We developed 3plex, a software able to predict TPXs in silico. We show that 3plex outperforms previous existing approaches leveraging the data collected in RNABSdb for lncRNAs known to form functional TPXs. Moreover this analysis shows that TPXs tend to be shorter and more degenerated than previously expected. Finally, we applied 3plex to all the lncRNAs collected in RNABSdb and we show that the majority of them could directly bind the genome by TPXs formation. Data and software are available at https://molinerislab.github.io/RNABSdb/ and https://github.com/molinerisLab/3plex.

bioinformatics↗

Subepidermal blisters are healed by wedge-shaped keratinocytes of hair follicle origin

Injury in adult tissue generally reactivates developmental programs to foster regeneration, but it is not known whether this paradigm applies to growing tissue. Here, by employing blisters, we show that epidermal wounds heal at the expense of skin development. The regenerated epidermis suppresses the expression of tissue morphogenesis genes accompanied by delayed hair follicle (HF) growth. Lineage tracing experiments, cell proliferation dynamics, and mathematical modeling reveal that the progeny of HF junctional zone stem cells, which undergo a morphological transformation, repair the blisters while not promoting HF development. In contrast, the contribution of interfollicular stem cell progeny to blister healing is small. These findings demonstrate that tissue development can be sacrificed for the sake of wound regeneration and suggest that tissue repair does not coincide with the reactivation of developmental programs in all regenerative contexts. Our study elucidates the key cellular mechanism of wound healing in skin blistering diseases.

cell biology↗

Dysregulation of splicing-related proteins in prostate cancer is controlled by FOXA1

Prostate cancer (PCa) is genomically driven by dysregulation of transcriptional networks involving the transcriptional factors (TFs) FOXA1, ERG, AR, and HOXB13. However, the role of these specific TFs in the regulation of alternative pre-mRNA splicing (AS), which is a proven therapeutic vulnerability for cancers driven by the TF MYC, is not described. Using transcriptomic datasets from PCa patients, we tested for an association between expression of FOXA1, ERG, AR, HOXB13, and MYC, and genes involved in AS - termed splicing-related proteins (SRPs), which have pleiotropic roles in RNA metabolism. We identified FOXA1 as the strongest predictor of dysregulated SRP gene expression, which was associated with PCa disease relapse after treatment. Subsequently, we selected a subset of FOXA1-binding and actively-transcribed SRP genes that phenocopy the FOXA1 dependency of PCa cells, and confirmed in vitro via knockdown and over-expression that FOXA1 regulates SRP gene expression. Finally, we demonstrated the persistence of a FOXA1-SRP gene association in treatment-relapsed castration-resistant PCa (CRPCa) patients. Our data demonstrate, for the first time, that FOXA1 controls dysregulated SRP gene expression, which is associated with poor PCa patient outcomes. Analogous to MYC-driven cancers, our findings implicate the therapeutic targeting of SRPs and AS in FOXA1-overexpressing PCa.

cancer biology↗