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Forcato, M.

Publications and source records attributed to Forcato, M..

9 recordsLinked to original sources

The RNA helicase DDX21 cooperates with ETS1 and FLI1 in cell cycle, immune evasion, and snoRNA processing in activated B-cell-like diffuse large B-cell lymphoma cells

Diffuse large B-cell lymphoma (DLBCL) is a clinically and biologically heterogeneous disease, with the activated B-cell-like (ABC) subtype showing inferior outcomes. The ETS transcription factors ETS1 and FLI1 are recurrently gained and functionally relevant in DLBCL, yet their pathogenetic function is still to be fully elucidated. Here, we describe their cooperation with the RNA regulatory machinery, demonstrating that the RNA helicase DDX21 is a central effector of the ETS1/FLI1 transcriptional network in ABC-DLBCL. Our proteomic analyses revealed that ETS1 physically interacted with DDX21 and other RNA processing factors. As ETS1, DDX21 was preferentially expressed in ABC-DLBCL, particularly in the MCD/C5 genetic subtype, and it was associated with adverse clinical outcomes in this lymphoma subtype. Genetic and pharmacological studies demonstrated that DDX21 was essential for ABC-DLBCL cell proliferation. DDX21 also coordinated various transcriptional programs, which were revealed by integrated RNA-Seq, small RNA-Seq, ChIP-Seq, and Capture Hi-C analyses. DDX21-dependent transcription was relevant for ribosome biogenesis, MYC signaling, cell cycle progression, and immune evasion, but also regulated non-coding RNA networks, including microRNAs and small nucleolar RNAs, in particular SNORA37. Collectively, our data establish DDX21 as a nucleolar hub linking ETS transcription factors to coding and non-coding RNA programs that sustain aggressive lymphoma biology. These findings suggest DDX21 and ETS-RNA helicase complexes as promising therapeutic vulnerabilities in ABC-DLBCL.

cancer biology↗

FDXR Upregulation by p63/p73 is a Prognostic and Therapeutic Marker of HTLV-1-Associated Adult T Cell Leukemia/Lymphoma

Infection with human T-lymphotropic virus 1 (HTLV-1) can lead to severe diseases, including adult T-cell leukemia/lymphoma (ATL), for which current therapies are inadequate. HTLV-1 persists chronically through integration of its genome into host DNA and expansion of infected clones via cellular proliferation. Selective elimination of infected cells is the ideal treatment goal but requires identifying cellular markers dysregulated by HTLV-1 that can be exploited therapeutically. Combining metabolomics and proteomics analyses, we identified increased expression of the mitochondrial enzyme ferredoxin reductase (FDXR) as a hallmark of HTLV-1-infected cells. In patient cells, FDXR upregulation mirrored disease severity, was enriched in proliferating tumour cells and predicted worse ATL prognosis. Mechanistically, FDXR upregulation was directly driven by the transactivating isoforms of two p53 family members, TAp63 and TAp73. In silico drug susceptibility predictions, followed by targeted cytotoxicity, proliferation and Drug-Seq assays demonstrated that FDXR upregulation is associated with increased sensitivity of ATL cells to repurposed chemotherapeutic agents, particularly fluorouracil. Overall, our findings establish FDXR as a novel biomarker of HTLV-1-associated disease progression and ATL prognosis, elucidate its upstream molecular regulation, and highlight its predictive potential for chemotherapeutic sensitivity of ATL cells.

microbiology↗

SpaceTrooper: a quality control framework for imaging-basedspatial omics data

Quality control (QC) is a critical step in the analysis of imaging-based single-cell spatial omics data, yet standardized metrics tailored to these technologies are still lacking. Most existing QC approaches are adapted from single-cell sequencing workflows and rely on fixed thresholds, limiting their ability to capture complex artifacts arising from image processing, tissue morphology, and platform-specific effects. Here, we present SpaceTrooper, a data-driven QC framework that computes an integrated per-cell quality score by combining expression-derived and morphological features. Without relying on fixed thresholds, SpaceTrooper systematically identifies low-quality cells caused by segmentation errors, signal loss, elevated background, spatial distortions, and tissue-derived artifacts. Across diverse tissues, technologies, and modalities, SpaceTrooper robustly detects technical failures and substantially improves clustering and cell-type coherence relative to conventional QC strategies.

bioinformatics↗

ETV7 reduces inflammatory responses in breast cancer cells by repressing TNFR1/NF-kappaB axis

The transcription factor ETV7 is an oncoprotein that is up-regulated in all breast cancer (BC) types. We have recently demonstrated that ETV7 promoted breast cancer progression by increasing cancer cell proliferation and stemness and was also involved in the development of chemo- and radio-resistance. However, the roles of ETV7 in breast cancer inflammation have yet to be studied. Gene ontology analysis previously performed on BC cells stably over-expressing ETV7 demonstrated that ETV7 was involved in the suppression of innate immune and inflammatory responses. To better decipher the involvement of ETV7 in these signaling pathways, in this study, we identified TNFRSF1A, encoding for the main receptor of TNF-, TNFR1, as one of the genes down-regulated by ETV7. We demonstrated that ETV7 directly binds to the intron I of this gene, and we showed that the ETV7-mediated down-regulation of TNFRSF1A reduced the activation of NF-{kappa}B signaling. Furthermore, in this study, we unveiled a potential crosstalk between ETV7 and STAT3, another master regulator of inflammation. While it is known that STAT3 directly up-regulates the expression of TNFRSF1A, here we demonstrated that ETV7 reduces the ability of STAT3 to bind to the TNFRSF1A gene via a competitive mechanism, leading to the repression of its transcription. These results suggest that ETV7 can reduce the inflammatory responses in breast cancer through the down-regulation of TNFRSF1A.

cancer biology↗

Glycolysis downregulation is a hallmark of HIV-1 latency and sensitizes infected cells to oxidative stress

HIV-1 infects lymphoid and myeloid cells, which can harbor a latent proviral reservoir responsible for maintaining lifelong infection. Glycolytic metabolism has been identified as a determinant of susceptibility to HIV-1 infection, but its role in the development and maintenance of HIV-1 latency has not been elucidated. By combining transcriptomic, proteomic and metabolomic analysis, we here show that transition to latent HIV-1 infection downregulates glycolysis, while viral reactivation by conventional stimuli reverts this effect. Decreased glycolytic output in latently infected cells is associated with downregulation of NAD+/NADH. Consequently, infected cells rely on the parallel pentose phosphate pathway and its main product, the antioxidant NADPH, fueling antioxidant pathways maintaining HIV-1 latency. Of note, blocking NADPH downstream effectors, thioredoxin and glutathione, favors HIV-1 reactivation from latency in lymphoid and myeloid cellular models. This provides a "shock and kill effect" decreasing proviral DNA in cells from people-living-with-HIV/AIDS. Overall, our data show that downmodulation of glycolysis is a metabolic signature of HIV-1 latency that can be exploited to target latently infected cells with eradication strategies.

immunology↗

EphB6 regulates TFEB-lysosomal pathway and survival of disseminated indolent breast cancer cells

Late relapse of disseminated cancer cells is a common feature of some types of tumors. Several intrinsic and extrinsic factors have been shown to affect reawakening of disseminated dormant cancer cells (DDCCs); however, the signals and processes sustaining survival of DDCCs in a foreign environment are still poorly understood. We have recently shown that crosstalk with lung epithelial cells promotes persistence of DDCCs from estrogen receptor positive (ER+) breast tumors. Here we show that TFEB-lysosomal axis is activated in DDCCs and that it is modulated by the pro-survival ephrin receptor EphB6. TFEB lysosomal direct targets are enriched in DDCCs in vivo and correlate with relapse in ER+ breast cancer patients. Direct contact of DDCCs with alveolar type I-like lung epithelial cells drives lysosomal accumulation and EphB6 induction. EphB6 contributes to TFEB transcriptional activity and lysosome formation in DDCCs in vitro and in vivo, and supports survival of DDCCs in coculture and in vivo. Furthermore, signaling from EphB6 promotes the proliferative response of surrounding lung parenchymal cells in vivo.

cancer biology↗

ETV7 regulates breast cancer stem-like cell plasticity by repressing IFN-response genes

Cancer stem cells (CSCs) represent a population of cells within the tumor able to drive tumorigenesis and known to be highly resistant to conventional chemotherapy and radiotherapy. In this work, we show a new role for ETV7, a transcriptional repressor member of the ETS family, in promoting breast cancer stem-like cells plasticity and resistance to chemo- and radiotherapy in breast cancer (BC) cells. We observed that MCF7 and T47D BC-derived cells stably over-expressing ETV7 showed reduced sensitivity to the chemotherapeutic drug 5-Flouororuacil and to radiotherapy, accompanied by an adaptive proliferative behavior observed in different culture conditions. We further noticed that alteration of ETV7 expression could significantly affect the population of breast CSCs, measured by CD44+/CD24low cell population and mammosphere formation efficiency. By transcriptome profiling, we identified a signature of Interferon-responsive genes significantly repressed in cells over-expressing ETV7, which could be responsible for the increase in the breast CSCs population, as this could be partially reverted by the treatment with IFN-{beta}. Lastly, we show that the expression of the IFN-responsive genes repressed by ETV7 could have prognostic value in breast cancer, as low expression of these genes was associated with a worse prognosis. Therefore, we propose a novel role for ETV7 in breast cancer stem cells plasticity and associated resistance to conventional chemotherapy and radiotherapy, which involves the repression of a group of IFN-responsive genes, potentially reversible upon IFN-{beta} treatment. We, therefore, suggest that an in-depth investigation of this mechanism could lead to novel breast CSCs targeted therapies and to the improvement of combinatorial regimens, possibly involving the therapeutic use of IFN-{beta}, with the aim of avoiding resistance development and relapse in breast cancer.

cancer biology↗

FGFR2 fusion protein-driven mouse models of intrahepatic cholangiocarcinoma unveil a necessary role for Erk signalling

Background and aimsAbout 15% of intrahepatic cholangiocarcinoma (iCCA) express fibroblast growth factor receptor 2 (FGFR2) fusion proteins (FFs), most often in concert with mutationally inactivated TP53, CDKN2A or BAP1. FFs span residues 1-768 of FGFR2 fused to sequences encoded by any of a long list (>60) of partner genes, a configuration sufficient to ignite oncogenic FF activation. In line, FGFR-specific tyrosine kinase inhibitors (F-TKI) were shown to provide clinical benefit in FF+ iCCA, although responses were partial and/or limited by resistance mechanisms, including the FF V565F gatekeeper mutation. Herein we present an FF-driven murine iCCA model and exploit its potential for pre-clinical studies on FF therapeutic targeting. MethodsFour iCCA FFs carrying different fusion sequences were expressed in Tp53-/- mouse liver organoids. Tumorigenic properties of genetically modified liver organoids were assessed by intrahepatic/subcutaneous transplantation in immuno-deficient mice. Cellular models derived from neoplastic lesions were exploited for pre-clinical studies. ResultsTumors diagnosed as CCA were obtained upon transplantation of FF-expressing liver organoids. The penetrance of this tumorigenic phenotype was influenced by FF identity. Tumor organoids and 2D cell lines derived from CCA lesions were addicted to FF signaling via Ras-Erk, regardless of FF identity or presence of V565F mutation. Double blockade of FF-Ras-Erk pathway by concomitant pharmacological inhibition of FFs and Mek1/2 provided greater therapeutic efficacy than single agent F-TKI in vitro and in vivo. ConclusionsFF-driven iCCA pathogenesis was successfully modelled in murine Tp53-/- background. This model revealed biological heterogeneity among structurally different FFs. Double blockade of FF-Erk signaling deserves consideration for improving precision-based approaches against human FF+ iCCA. Abbreviations used in this paper: ANOVA, analysis of variance; Bap1, BRCA1-Associated-Protein 1; Cdkn2a, cyclin-dependent kinase inhibitor 2A; Cftr, cystic fibrosis transmembrane conductance regulator; Ck19, cytokeratin 19; Cyp3A, cytochrome P450, family 3, subfamily A; EGF, Epidermal growth factor; EGFR, Epidermal growth factor receptor; EpCAM, epithelial cell adhesion molecule; Erk, extracellular signal-regulated kinase; FGFR2, fibroblast growth factor receptor 2; FRS2, fibroblast growth factor receptor substrate 2; GRB2, growth factor receptor-bound 2; GSEA, gene set enrichment analysis; GSVA, gene set variation analysis; H&E, hematoxylin and eosin; HepPar1, hepatocyte Paraffin 1; Hnf4-7, hepatocyte nuclear factor 4 alpha; Hprt, hypoxanthine-guanine phosphoribosyl transferase; LGR5, leucine-rich repeat-containing G-protein coupled receptor 5; NTRK, neurotrophic Tyrosine Kinase; Parp, Poly (ADP-ribose) polymerase; RECIST, response evaluation criteria in solid tumors; SHP2, Src homology phosphatase 2; Ttr, transthyretin.

cancer biology↗

Alterations of redox and iron metabolism accompany development of HIV latency.

Metabolic alterations, such as oxidative stress, are hallmarks of HIV-1 infection. However, their influence on the development of viral latency, and thus on HIV-1 persistence during antiretroviral therapy (ART), have just begun to be explored. We analyzed omics profiles of in-vitro and in-vivo models of infection by HIV-1 and its simian homolog SIVmac. We found that cells survive retroviral replication by upregulating antioxidant pathways and intertwined iron import pathways. These changes are associated with remodeling of the redox sensitive promyelocytic leukemia protein nuclear bodies (PML NBs), an important constituent of nuclear architecture and a marker of HIV-1 latency. We found that PML is depleted in productively infected cells and restored by ART. Moreover, we identified intracellular iron as a key link between oxidative stress and PML depletion, thus supporting iron metabolism modulators as pharmacological tools to impair latency establishment.

molecular biology↗