Publications by authors named "Laura Botti"

Breast cancer is the most frequent type of tumor in women and is characterized by variable outcomes due to its heterogeneity and the presence of many cancer cell-autonomous and -non-autonomous factors. A major determinant of breast cancer aggressiveness is represented by immune infiltration, which can support tumor development. In our work, we studied the role of mast cells in breast cancer and identified a novel activity in promoting the tumor-initiating properties of cancer cells.

View Article and Find Full Text PDF
Article Synopsis
  • * Research using a mouse model revealed that mast cells (MCs) produce a protein called osteopontin (OPN), which helps inhibit NEPC growth through TNFα production when triggered by NEPC cells.
  • * The study identified syndecan-1 (SDC1) as a specific ligand for NEPC that activates this protective pathway, suggesting MCs could be a target for new therapies and SDC1 might serve as a biomarker for early detection of NEPC.
View Article and Find Full Text PDF

Castration-resistant prostate cancer (CRPC) eventually becomes resistant to androgen receptor pathway inhibitors like enzalutamide. Immunotherapy also fails in CRPC. We propose a new approach to simultaneously revert enzalutamide resistance and rewire anti-tumor immunity.

View Article and Find Full Text PDF

Acute myeloid leukemia (AML) progression is influenced by immune suppression induced by leukemia cells. ZEB1, a critical transcription factor in epithelial-to-mesenchymal transition, demonstrates immune regulatory functions in AML. Silencing ZEB1 in leukemic cells reduces engraftment and extramedullary disease in immune-competent mice, activating CD8 T lymphocytes and limiting Th17 cell expansion.

View Article and Find Full Text PDF

Background: Osteosarcoma (OS) is the most common primary bone tumor in children and adolescent. Surgery and multidrug chemotherapy are the standard of treatment achieving 60-70% of event-free survival for localized disease at diagnosis. However, for metastatic disease, the prognosis is dismal.

View Article and Find Full Text PDF

Unlabelled: Breast cancer is the most common type of cancer in women worldwide, with the luminal subtype being the most widespread. Although characterized by better prognosis compared with other subtypes, luminal breast cancer is still considered a threatening disease due to therapy resistance, which occurs via both cell- and non-cell-autonomous mechanisms. Jumonji domain-containing 6, arginine demethylase and lysine hydroxylase (JMJD6) is endowed with a negative prognostic value in luminal breast cancer and, via its epigenetic activity, it is known to regulate many intrinsic cancer cell pathways.

View Article and Find Full Text PDF

Background: Autoimmune disorders, including Systemic Lupus Erythematosus (SLE), are associated with increased incidence of hematological malignancies. The matricellular protein osteopontin (OPN) has been linked to SLE pathogenesis, as SLE patients show increased serum levels of OPN and often polymorphisms in its gene. Although widely studied for its pro-tumorigenic role in different solid tumours, the role of OPN in autoimmunity-driven lymphomagenesis has not been investigated yet.

View Article and Find Full Text PDF
Article Synopsis
  • Cancer can alter the bone marrow (BM) environment, making it more supportive of tumor growth, with changes influenced by the tumor's tissue of origin.
  • A study using a breast cancer model found that bone marrow mesenchymal stem cells (MSC) respond to cancer cells by releasing IL1B, which activates the transcription factor ATF3 in hematopoietic stem cells, promoting myeloid cell differentiation.
  • The findings suggest that measuring ATF3 levels in blood cells could help differentiate between malignant and benign conditions early on, and blocking IL1B may be a potential treatment strategy for breast cancer patients.*
View Article and Find Full Text PDF

Dysregulated fatty acid metabolism interacts with oncogenic signals, thereby worsening tumor aggressiveness. The stearoyl-CoA desaturating enzymes, SCD1 and SCD5, convert of saturated fatty acids to monounsaturated fatty acids. While SCD1 is frequently overexpressed in tumor cells and has been widely studied, SCD5 has both limited expression and poor characterization.

View Article and Find Full Text PDF
Article Synopsis
  • - Neutrophil extracellular traps (NETs) are specialized structures made of DNA and proteins that interact with dendritic cells, which helps activate the immune response through the presentation of antigens associated with these NETs.
  • - Unlike typical cell death processes, NETosis preserves functional proteins on DNA threads, maintaining their activity and immunogenic properties, and can also involve leukemic cells releasing traps with cancer-related antigens, such as the mutant nucleophosmin (NPMc+).
  • - A study demonstrated that a vaccine combining dendritic cells and NPMc+ NETs significantly reduced leukemia-related myeloproliferation in mouse models, promoted antibody production against mutant NPMc, and fostered a CD8
View Article and Find Full Text PDF

The secreted protein acidic and rich in cysteine (SPARC) is a matricellular protein with unexpected immunosuppressive function in myeloid cells. We investigated the role of SPARC in autoimmunity using the pristane-induced model of lupus that, in mice, mimics human systemic lupus erythematosus (SLE). mice developed earlier and more severe renal disease, multi-organ parenchymal damage, and arthritis than the wild-type counterpart.

View Article and Find Full Text PDF
Article Synopsis
  • Mature T cells in the bone marrow maintain homeostasis with the help of regulatory T cells (Tregs) and bone marrow-mesenchymal stem cells (BM-MSCs), but this balance is disrupted by BM transplantation (BMT), leading to issues with B-cell development.
  • The study investigates the role of CD40, derived from radio-resistant cells in the host, in re-establishing the balance between T-effector (Teff) and Treg cells after BMT, using a murine model to assess T cell responses.
  • Results indicate that lethal irradiation enhances CD40 and OX40L levels in BM-MSCs, where CD40 restrains OX40L, promoting Treg stability and improving B-cell
View Article and Find Full Text PDF

Background: Intra-tumour heterogeneity in lymphoid malignancies encompasses selection of genetic events and epigenetic regulation of transcriptional programs. Clonal-related neoplastic cell populations are unsteadily subjected to immune editing and metabolic adaptations within different tissue microenvironments. How tissue-specific mesenchymal cells impact on the diversification of aggressive lymphoma clones is still unknown.

View Article and Find Full Text PDF
Article Synopsis
  • Researchers explored the role of mast cells (MCs) in breast cancer, discovering that they promote tumor growth by shifting cancer cell characteristics towards a luminal gene program while inhibiting basal features.
  • The study found that when MCs were co-cultured with breast cancer cells, they activated estrogen receptors and reduced HER2 levels, which are associated with a more aggressive cancer phenotype.
  • Analysis of patient data showed a correlation between MC density and breast cancer outcomes, suggesting that MCs contribute to a higher risk of cancer relapse by altering tumor cell characteristics.
View Article and Find Full Text PDF

The presence of a growing tumor establishes a chronic state of inflammation that acts locally and systemically. Bone marrow responds to stress signals by expanding myeloid cells endowed with immunosuppressive functions, further fostering tumor growth and dissemination. How early in transformation the cross-talk with the bone marrow begins and becomes detectable in blood is unknown.

View Article and Find Full Text PDF

Myeloid-derived suppressor cells (MDSC) are well-known key negative regulators of the immune response during tumor growth, however scattered is the knowledge of their capacity to influence and adapt to the different tumor microenvironments and of the markers that identify those capacities. Here we show that the secreted protein acidic and rich in cysteine (SPARC) identifies in both human and mouse MDSC with immune suppressive capacity and pro-tumoral activities including the induction of epithelial-to-mesenchymal transition (EMT) and angiogenesis. In mice the genetic deletion of SPARC reduced MDSC immune suppression and reverted EMT.

View Article and Find Full Text PDF

Osteosarcoma, the most common primary bone tumor, is characterized by an aggressive behavior with high tendency to develop lung metastases as well as by multiple genetic aberrations that have hindered the development of targeted therapies. New therapeutic approaches are urgently needed; however, novel combinations with immunotherapies and checkpoint inhibitors require suitable preclinical models with intact immune systems to be properly tested. We have developed immunocompetent osteosarcoma models that grow orthotopically in the bone and spontaneously metastasize to the lungs, mimicking human osteosarcoma.

View Article and Find Full Text PDF

Systemic immune stimulation has been associated with increased risk of myeloid malignancies, but the pathogenic link is unknown. We demonstrate in animal models that experimental systemic immune activation alters the bone marrow stromal microenvironment, disarranging extracellular matrix (ECM) microarchitecture, with downregulation of secreted protein acidic and rich in cysteine (SPARC) and collagen-I and induction of complement activation. These changes were accompanied by a decrease in Treg frequency and by an increase in activated effector T cells.

View Article and Find Full Text PDF

Prostate cancer is a leading cause of cancer-related death in males worldwide. Indeed, advanced and metastatic disease characterized by androgen resistance and often associated with neuroendocrine (NE) differentiation remains incurable. Using the spontaneous prostate cancer TRAMP model, we have shown that mast cells (MCs) support in vivo the growth of prostate adenocarcinoma, whereas their genetic or pharmacologic targeting favors prostate NE cancer arousal.

View Article and Find Full Text PDF

The extracellular matrix (ECM) contributes to the biological and clinical heterogeneity of breast cancer, and different prognostic groups can be identified according to specific ECM signatures. In high-grade, but not low-grade, tumors, an ECM signature characterized by high SPARC expression (ECM3) identifies tumors with increased epithelial-to-mesenchymal transition (EMT), reduced treatment response, and poor prognosis. To better understand how this ECM3 signature is contributing to tumorigenesis, we expressed SPARC in isogenic cell lines and found that SPARC overexpression in tumor cells reduces their growth rate and induces EMT.

View Article and Find Full Text PDF

Purpose: Exosomes deliver signals to target cells and could thus be exploited as an innovative therapeutic tool. We investigated the ability of membrane TRAIL-armed exosomes to deliver proapoptotic signals to cancer cells and mediate growth inhibition in different tumor models.

Experimental Methods And Results: K562 cells, transduced with lentiviral human membrane TRAIL, were used for the production of TRAIL(+) exosomes, which were studied by nanoparticle tracking analysis, cytofluorimetry, immunoelectronmicroscopy, Western blot, and ELISA.

View Article and Find Full Text PDF

Neoplastic B-cell clones commonly arise within secondary lymphoid organs (SLO). However, during disease progression, lymphomatous cells may also colonize the bone marrow (BM), where they localize within specialized stromal niches, namely the osteoblastic and the vascular niche, according to their germinal center- or extra-follicular-derivation, respectively. We hypothesized the existence of common stromal motifs in BM and SLO B-cell lymphoid niches involved in licensing normal B-cell development as well as in fostering transformed B lymphoid cells.

View Article and Find Full Text PDF

The matricellular protein osteopontin (OPN, Spp-1) is widely associated with cancer aggressiveness when produced by tumor cells, but its impact is uncertain when produced by leukocytes in the context of the tumor stroma. In a broad study using Spp1(-/-) mice along with gene silencing in tumor cells, we obtained evidence of distinct and common activities of OPN when produced by tumor or host cells in a spontaneously metastatic model of breast cancer. Different cellular localization of OPN is associated with its distinct activities, being mainly secreted in tumor cells while intracellular in myeloid cells.

View Article and Find Full Text PDF

We present measurements of the light-scattering phase function of selected carbon and ash particles in the geometric-optics regime in which the particle diameter is much larger than the wavelength of the light source. Measurements were performed on both single particles and particle ensembles. This was accomplished with two separate methodologies: an electrodynamic levitator for single-particle measurements and a particle feeder for the ensemble measurements.

View Article and Find Full Text PDF