0000000000486071
AUTHOR
Sabina Sangaletti
showing 56 related works from this author
The bone marrow stroma in hematological neoplasms—a guilty bystander
2011
In the setting of hematological neoplasms, changes in the bone marrow (BM) stroma might arise from pressure exerted by the neoplastic clone in shaping a supportive microenvironment, or from chronic perturbation of the BM homeostasis. Under such conditions, alterations in the composition of the BM stroma can be profound, and could emerge as relevant prognostic factors. In this Review, we delineate the multifaceted contribution of the BM stroma to the pathobiology of several hematological neoplasms, and discuss the impact of stromal modifications on the natural course of these diseases. Specifically, we highlight the involvement of BM stromal components in lymphoid and myeloid malignancies, a…
SPARC regulation of PMN clearance protects from pristane induced lupus and rheumatoid arthritis
2020
AbstractOne step along the pathogenesis of Systemic lupus erythematosus (SLE) is associated with polymorphonuclear leukocyte (PMN) death and their ineffective removal by M2-macrophages. The secreted protein acidic and rich in cysteine (SPARC) is a matricellular protein with unexpected immunosuppressive function in M2-macrophages and myeloid cells. To investigate the role of SPARC in autoimmunity, we adopted a pristane–induced model of lupus in mice, which recapitulates clinical manifestations of human SLE. Sparc-/- mice developed earlier and more severe renal disease, lung and liver parenchymal damage than the WT counterpart. Most prominently, Sparc-/- mice had anticipated and severe occurr…
Role of PD-L1 expression in triple-negative breast cancer stem cells.
2018
12081Background: Triple negative breast cancer (TNBC) is characterized by poor prognosis, lack of specific-targeted agents and is in need of new therapeutics. Immune checkpoint blockers have shown ...
Stromal niche communalities underscore the contribution of the matricellular protein SPARC to B-cell development and lymphoid malignancies
2014
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. Thus, we tested the expression of prototypical mesenchymal stromal cell (MSC) markers and regulatory matricellular proteins in human BM and SLO u…
A Spatially Resolved Dark- Versus Light-Zone Microenvironment Signature Subdivides Germinal Center-Related Aggressive B-Cell Lymphomas
2020
Summary: We applied digital spatial profiling for 87 immune and stromal genes to lymph node germinal center (GC) dark- and light-zone (DZ/LZ) regions of interest to obtain a differential signature of these two distinct microenvironments. The spatially resolved 53-genes signature, comprising key genes of the DZ mutational machinery and LZ immune and mesenchymal milieu, was applied to the transcriptomes of 543 GC-related diffuse large B cell lymphomas and double-hit (DH) lymphomas. According to the DZ/LZ signature, the GC-related lymphomas were sub-classified into two clusters. The subgroups differed in the distribution of DH cases and survival, with most DH displaying a distinct DZ-like prof…
Persistent immune stimulation exacerbates genetically driven myeloproliferative disorders via stromal remodeling
2017
Abstract 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. Under these conditions, hematopoietic precursors harboring nucleophosmin-1 (NPM1) mutation generated myeloid cells unfit for normal …
The good and bad of targeting cancer-associated extracellular matrix
2017
The maintenance of tissue homeostasis requires extracellular matrix (ECM) remodeling. Immune cells actively participate in regenerating damaged tissues contributing to ECM deposition and shaping. Dysregulated ECM deposition characterizes fibrotic diseases and cancer stromatogenesis, where a chronic inflammatory state sustains the ECM increase. In cancer, the ECM fosters several steps of tumor progression, providing pro-survival and proliferative signals, promoting tumor cell dissemination via collagen fibers or acting as a barrier to impede drug diffusion. Interfering with processes leading to chronic ECM deposition, as occurring in cancer, might allow the simultaneous targeting of both pri…
Intracellular osteopontin protects from autoimmunity-driven lymphoma development inhibiting TLR9-MYD88-STAT3 signaling
2022
Abstract 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. Methods To test the role of OPN in the SLE-associated lymphomagenesis, the SLE-like prone Faslpr/lpr mutation was transferred onto an OPN-deficient background. Spleen from Faslpr/lpr and OPN-/-Faslpr/lpr …
RORC1 Regulates Tumor-Promoting "Emergency" Granulo-Monocytopoiesis
2015
Cancer-driven granulo-monocytopoiesis stimulates expansion of tumor promoting myeloid populations, mostly myeloid-derived suppressor cells (MDSCs) and tumor-associated macrophages (TAMs). We identified subsets of MDSCs and TAMs based on the expression of retinoic-acid-related orphan receptor (RORC1/RORγ) in human and mouse tumor bearers. RORC1 orchestrates myelopoiesis by suppressing negative (Socs3 and Bcl3) and promoting positive (C/EBPβ) regulators of granulopoiesis, as well as the key transcriptional mediators of myeloid progenitor commitment and differentiation to the monocytic/macrophage lineage (IRF8 and PU.1). RORC1 supported tumor-promoting innate immunity by protecting MDSCs from …
Mesenchymal Transition of High-Grade Breast Carcinomas Depends on Extracellular Matrix Control of Myeloid Suppressor Cell Activity
2016
SummaryThe 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. SPARC expression also results in the formation of a h…
Antibody-mediated blockade of JMJD6 interaction with collagen I exerts antifibrotic and antimetastatic activities
2017
JMJD6 is known to localize in the nucleus, exerting histone arginine demethylase and lysyl hydroxylase activities. A novel localization of JMJD6 in the extracellular matrix, resulting from its secretion as a soluble protein, was unveiled by a new anti-JMJD6 mAb called P4E11, which was developed to identify new targets in the stroma. Recombinant JMJD6 binds with collagen type I (Coll-I), and distinct JMJD6 peptides interfere with collagen fibrillogenesis, collagen-fibronectin interaction, and adhesion of human tumor cells to the collagen substrate. P4E11 and collagen binding to JMJD6 are mutually exclusive because the amino acid sequences of JMJD6 necessary for the interaction with Coll-I ar…
Stromal SPARC contributes to the detrimental fibrotic changes associated with myeloproliferation whereas its deficiency favors myeloid cell expansion.
2012
Abstract In myeloid malignancies, the neoplastic clone outgrows normal hematopoietic cells toward BM failure. This event is also sustained by detrimental stromal changes, such as BM fibrosis and osteosclerosis, whose occurrence is harbinger of a dismal prognosis. We show that the matricellular protein SPARC contributes to the BM stromal response to myeloproliferation. The degree of SPARC expression in BM stromal elements, including CD146+ mesenchymal stromal cells, correlates with the degree of stromal changes, and the severity of BM failure characterizing the prototypical myeloproliferative neoplasm primary myelofibrosis. Using Sparc−/− mice and BM chimeras, we demonstrate that SPARC contr…
Intra-tumor heterogeneity of Diffuse Large B-cell Lymphoma involves the induction of diversified stroma-tumor interfaces
2020
ABSTRACTIntra-tumor heterogeneity in lymphoid malignancies is articulated around several fundamentals, encompassing selection of genetic subclonal events and epigenetic regulation of transcriptional programs. Clonally-related neoplastic cell populations are unsteadily subjected to immune editing and metabolic adaptations within different tissue microenvironments. How tissue-intrinsic mesenchymal determinants impact on the diversification of aggressive lymphomas is still unknown. In this study we adopted the established A20 line-based model of Diffuse Large B-cell Lymphoma (DLBCL), to investigate the intra-tumor heterogeneity associated with the infiltration of different tissue microenvironm…
The ins and outs of osteopontin.
2015
The continuous remodeling of progressing tumors demands non-physiologic production of extracellular matrix (ECM) proteins. Among them, osteopontin (OPN) has been largely involved in tumor progression and metastasis. We have recently discovered a new mechanism for OPN in the metastatic spread of mammary carcinoma providing local immunosuppression at the seeding site.
Release of IFNγ by Acute Myeloid Leukemia Cells Remodels Bone Marrow Immune Microenvironment by Inducing Regulatory T Cells
2022
Abstract Purpose: The stromal and immune bone marrow (BM) landscape is emerging as a crucial determinant for acute myeloid leukemia (AML). Regulatory T cells (Treg) are enriched in the AML microenvironment, but the underlying mechanisms are poorly elucidated. Here, we addressed the effect of IFNγ released by AML cells in BM Treg induction and its impact on AML prognosis. Experimental Design: BM aspirates from patients with AML were subdivided according to IFNG expression. Gene expression profiles in INFγhigh and IFNγlow samples were compared by microarray and NanoString analysis and used to compute a prognostic index. The IFNγ release effect on the BM microenvironment was investigated in me…
SPARC is a new myeloid-derived suppressor cell marker licensing suppressive activities
2019
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. Sparc−/− MDSC were less suppressive overall and the granu…
WNT signaling modulates PD-L1 expression in the stem cell compartment of triple-negative breast cancer
2019
Triple-negative breast cancers (TNBCs) are characterized by a poor prognosis and lack of targeted treatments, and thus, new therapeutic strategies are urgently needed. Inhibitors against programmed death-1 (PD-1)/PD-1 ligand (PD-L1) have shown significant efficacy in various solid cancers, but their activity against TNBCs remains limited. Here, we report that human TNBCs molecularly stratified for high levels of PD-L1 (PD-L1High) showed significantly enriched expression of immune and cancer stemness pathways compared with those with low PD-L1 expression (PD-L1Low). In addition, the PD-L1High cases were significantly associated with a high stemness score (SSHigh) signature. TNBC cell lines g…
Neutrophil extracellular traps arm DC vaccination against NPM-mutant myeloproliferation
2022
Neutrophil extracellular traps (NETs) are web-like chromatin structures composed by dsDNA and histones, decorated with antimicrobial proteins. Their interaction with dendritic cells (DCs) allows DC activation and maturation toward presentation of NET-associated antigens. Differently from other types of cell death that imply protein denaturation, NETosis preserves the proteins localized onto the DNA threads for proper enzymatic activity and conformational status, including immunogenic epitopes. Besides neutrophils, leukemic cells can release extracellular traps displaying leukemia-associated antigens, prototypically mutant nucleophosmin (NPMc+) that upon mutation translocates from nucleolus …
Myeloid cell heterogeneity in lung cancer: implication for immunotherapy
2020
Lung is a specialized tissue where metastases from primary lung tumors takeoff and those originating from extra-pulmonary sites land. One commonality characterizing these processes is the supportive role exerted by myeloid cells, particularly neutrophils, whose recruitment is facilitated in this tissue microenvironment. Indeed, neutrophils have important part in the pathophysiology of this organ and the key mechanisms regulating neutrophil expansion and recruitment during infection can be co-opted by tumor cells to promote growth and metastasis. Although neutrophils dominate the myeloid landscape of lung cancer other populations including macrophages, dendritic cells, mast cells, basophils …
Mast cell targeting hampers prostate adenocarcinoma development but promotes the occurrence of highly malignant neuroendocrine cancers
2011
Abstract Mast cells (MC) are c-Kit–expressing cells, best known for their primary involvement in allergic reactions, but recently reappraised as important players in either cancer promotion or inhibition. Here, we assessed the role of MCs in prostate tumor development. In prostate tumors from both tumor-prone transgenic adenocarcinoma of the mouse prostate (TRAMP) mice and human patients, MCs are specifically enriched and degranulated in areas of well-differentiated (WD) adenocarcinoma but not around poorly differentiated (PD) foci that coexist in the same tumors. We derived novel TRAMP tumor cell lines, representative of WD and PD variants, and through pharmacologic stabilization or geneti…
CD40 provides immune privilege to the bone marrow hematopoietic niche
2020
AbstractAllogeneic bone marrow transplantation remains the only therapeutic option for a wide range of hematological malignancies despite the risk of possible adverse, immune-related events, such as infection and acute graft-versus-host disease (aGVHD). aGVHD is characterized by T-cell activation, defective B-cell development and osteoblastic niche destruction in bone marrow (BM) among other issues. Transplant conditioning regimens cause excessive inflammatory cytokines production and impaired regulatory T-cell control of aberrant T-cell activation. Here, we show that mesenchymal cells (MSCs) upregulated CD40 upon irradiation at the expense of mesenchymal markers, and that CD40 endows MSC o…
Intra-tumour heterogeneity of diffuse large B-cell lymphoma involves the induction of diversified stroma-tumour interfaces
2020
Abstract 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. Methods Combining in situ quantitative immunophenotypical analyses and RNA sequencing we investigated the intra-tumour heterogeneity and the specific mesenchymal modifications that are associated with A20 diffuse large B-cell lymphoma (DLBCL) cells seeding of d…
Osteopontin shapes immunosuppression in the metastatic niche.
2014
Abstract 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. OPN produced by tumor cells supported their survival in the blood stream, wherea…
SPARC regulation of PMN clearance protects from pristane-induced lupus and rheumatoid arthritis
2021
Summary 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). Sparc−/− mice developed earlier and more severe renal disease, multi-organ parenchymal damage, and arthritis than the wild-type counterpart. Sparc+/- heterozygous mice showed an intermediate phenotype suggesting Sparc gene dosage in autoimmune-related events. Mechanistically, reduced Sparc expression in neutrophils blocks their clearance by macrophages, through defective delivery of don'…
SOCS2 controls proliferation and stemness of hematopoietic cells under stress conditions and its deregulation marks unfavorable acute leukemias
2015
Abstract Hematopoietic stem cells (HSC) promptly adapt hematopoiesis to stress conditions, such as infection and cancer, replenishing bone marrow–derived circulating populations, while preserving the stem cell reservoir. SOCS2, a feedback inhibitor of JAK–STAT pathways, is expressed in most primitive HSC and is upregulated in response to STAT5-inducing cytokines. We demonstrate that Socs2 deficiency unleashes HSC proliferation in vitro, sustaining STAT5 phosphorylation in response to IL3, thrombopoietin, and GM-CSF. In vivo, SOCS2 deficiency leads to unrestricted myelopoietic response to 5-fluorouracil (5-FU) and, in turn, induces exhaustion of long-term HSC function along serial bone marro…
Trabectedin Overrides Osteosarcoma Differentiative Block and Reprograms the Tumor Immune Environment Enabling Effective Combination with Immune Check…
2016
Abstract Purpose: 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. Experimental Design: We have developed immunocompetent osteosarcoma models that grow orthotopically in the bone and spontaneously metastasize to the lungs, mimicking human osteosarcoma. These models have been used to test the effica…
T Cells Expressing Receptor Recombination/Revision Machinery Are Detected in the Tumor Microenvironment and Expanded in Genomically Over-unstable Mod…
2021
AbstractTumors undergo dynamic immunoediting as part of a process that balances immunologic sensing of emerging neoantigens and evasion from immune responses. Tumor-infiltrating lymphocytes (TIL) comprise heterogeneous subsets of peripheral T cells characterized by diverse functional differentiation states and dependence on T-cell receptor (TCR) specificity gained through recombination events during their development. We hypothesized that within the tumor microenvironment (TME), an antigenic milieu and immunologic interface, tumor-infiltrating peripheral T cells could reexpress key elements of the TCR recombination machinery, namely, Rag1 and Rag2 recombinases and Tdt polymerase, as a poten…
Genetic deletion of osteopontin in TRAMP mice skews prostate carcinogenesis from adenocarcinoma to aggressive human-like neuroendocrine cancers
2015
// Giorgio Mauri 1 , Elena Jachetti 1 , Barbara Comuzzi 1 , Matteo Dugo 2 , Ivano Arioli 1 , Silvia Miotti 1 , Sabina Sangaletti 1 , Emma Di Carlo 3, 4 , Claudio Tripodo 5 , Mario P. Colombo 1 1 Molecular Immunology Unit, Department of Experimental Oncology and Molecular Medicine, Fondazione IRCCS Istituto Nazionale Tumori, 20133, Milano, Italy 2 Functional Genomics and Bioinformatics, Department of Experimental Oncology and Molecular Medicine, Fondazione IRCCS Istituto Nazionale Tumori, 20133, Milano, Italy 3 Department of Medicine and Science of Aging, Section of Anatomic Pathology and Molecular Medicine, “G. d’Annunzio” University, 66100, Chieti, Italy 4 Ce.S.I. Aging Research Center, “G…
The EU-funded I3LUNG Project:Integrative Science, Intelligent Data Platform for Individualized LUNG Cancer Care With Immunotherapy
2023
Although immunotherapy (IO) has changed the paradigm for the treatment of patients with advanced non-small cell lung cancers (aNSCLC), only around 30% to 50% of treated patients experience a long-term benefit from IO. Furthermore, the identification of the 30 to 50% of patients who respond remains a major challenge, as programmed Death-Ligand 1 (PD-L1) is currently the only biomarker used to predict the outcome of IO in NSCLC patients despite its limited efficacy. Considering the dynamic complexity of the immune system-tumor microenvironment (TME) and its interaction with the host's and patient's behavior, it is unlikely that a single biomarker will accurately predict a patient's outcomes. …
CD40 activity on mesenchymal cells negatively regulates OX40L to maintain bone marrow immune homeostasis under stress conditions
2021
BackgroundWithin the bone marrow (BM), mature T cells are maintained under homeostatic conditions to facilitate proper hematopoietic development. This homeostasis depends upon a peculiar elevated frequency of regulatory T cells (Tregs) and immune regulatory activities from BM-mesenchymal stem cells (BM-MSCs). In response to BM transplantation (BMT), the conditioning regimen exposes the BM to a dramatic induction of inflammatory cytokines and causes an unbalanced T-effector (Teff) and Treg ratio. This imbalance negatively impacts hematopoiesis, particularly in regard to B-cell lymphopoiesis that requires an intact cross-talk between BM-MSCs and Tregs. The mechanisms underlying the ability of…
Abstract 2877: Dual role of mast cells in prostate tumors.
2013
Abstract Prostatic carcinoma is most often a multifocal disease, with areas of localized, well-differentiated adenocarcinomas coexisting with poorly differentiated lesions within the same tumor. Mast cells (MC), classically known as the primary responders in allergic reactions, have been recently indicate of prognostic value in prostate cancer. We have evidence of a dual role of MC in prostate cancer. Within the same human tumor, MC are specifically enriched and degranulated in areas of adenocarcinoma, whereas few around anaplastic foci. This observation has been confirmed in tumors from TRAMP (Transgenic Adenocarcinoma of the Mouse Prostate) mice, and in two novel tumor cells lines, derive…
Oncogene-driven intrinsic inflammation induces leukocyte production of tumor necrosis factor that critically contributes to mammary carcinogenesis.
2010
Abstract Oncogene activation promotes an intrinsic inflammatory pathway that is crucial for cancer development. Here, we have investigated the actual effect of the inflammatory cytokine tumor necrosis factor (TNF) on the natural history of spontaneous mammary cancer in the HER2/neuT (NeuT) transgenic mouse model. Bone marrow transplantation from TNF knockout mice into NeuT recipients significantly impaired tumor growth, indicating that the source of TNF fostering tumor development was of bone marrow origin. We show that the absence of leukocyte-derived TNF disarranged the tumor vasculature, which lacked pericyte coverage and structural integrity, leading to diffuse vascular hemorrhage and s…
Neutrophil extracellular traps mediate transfer of cytoplasmic neutrophil antigens to myeloid dendritic cells toward ANCA induction and associated au…
2012
AbstractAntineutrophil cytoplasmic antibodies (ANCAs) target proteins normally retained within neutrophils, indicating that cell death is involved in the autoimmunity process. Still, ANCA pathogenesis remains obscure. ANCAs activate neutrophils inducing their respiratory burst and a peculiar form of cell death, named NETosis, characterized by formation of neutrophil extracellular traps (NETs), decondensed chromatin threads decorated with cytoplasmic proteins endorsed with antimicrobial activity. NETs have been consistently detected in ANCA-associated small-vessel vasculitis, and this association prompted us to test whether the peculiar structure of NET favors neutrophil proteins uploading i…
Autoimmune skin inflammation is dependent on plasmacytoid dendritic cell activation by nucleic acids via TLR7 and TLR9
2010
Lupus-prone mice develop a chronic inflammatory response to cutaneous injury that depends on the production of type I interferon, TLR7, and TLR9.
Tumor-Derived Prostaglandin E2 Promotes p50 NF-κB-Dependent Differentiation of Monocytic MDSCs
2020
Abstract Myeloid-derived suppressor cells (MDSC) include immature monocytic (M-MDSC) and granulocytic (PMN-MDSC) cells that share the ability to suppress adaptive immunity and to hinder the effectiveness of anticancer treatments. Of note, in response to IFNγ, M-MDSCs release the tumor-promoting and immunosuppressive molecule nitric oxide (NO), whereas macrophages largely express antitumor properties. Investigating these opposing activities, we found that tumor-derived prostaglandin E2 (PGE2) induces nuclear accumulation of p50 NF-κB in M-MDSCs, diverting their response to IFNγ toward NO-mediated immunosuppression and reducing TNFα expression. At the genome level, p50 NF-κB promoted binding …
The matricellular protein SPARC supports follicular dendritic cell networking toward Th17 responses.
2011
Abstract Lymphnode swelling during immune responses is a transient, finely regulated tissue rearrangement, accomplished with the participation of the extracellular matrix. Here we show that murine and human reactive lymph nodes express SPARC in the germinal centres. Defective follicular dendritic cell networking in SPARC-deficient mice is accompanied by a severe delay in the arrangement of germinal centres and development of humoral autoimmunity, events that are linked to Th17 development. SPARC is required for the optimal and rapid differentiation of Th17 cells, accordingly we show delayed development of experimental autoimmune encephalomyelitis whose pathogenesis involves Th17. Not only h…
Transcriptional Profiles and Stromal Changes Reveal Bone Marrow Adaptation to Early Breast Cancer in Association with Deregulated Circulating microRN…
2020
Abstract 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. Here, gene expression profiling of the bone marrow along disease progression in a spontaneous model of mammary carcinogenesis demonstrates that transcriptional modifications in the hematopoietic compartment occurred as early as preinvasive disease stages. The transcriptional profile showed downregulation…
SCD5-induced oleic acid production reduces melanoma malignancy by intracellular retention of SPARC and cathepsin B
2015
A proper balance between saturated and unsaturated fatty acids (FAs) is required for maintaining cell homeostasis. The increased demand of FAs to assemble the plasma membranes of continuously dividing cancer cells might unbalance this ratio and critically affect tumour outgrowth. We unveiled the role of the stearoyl-CoA desaturase SCD5 in converting saturated FAs into mono-unsaturated FAs during melanoma progression. SCD5 is down-regulated in advanced melanoma and its restored expression significantly reduced melanoma malignancy, both in vitro and in vivo, through a mechanism governing the secretion of extracellular matrix proteins, such as secreted protein acidic and rich in cysteine (SPAR…
Common extracellular matrix regulation of myeloid cell activity in the bone marrow and tumor microenvironments
2017
The complex interaction between cells undergoing transformation and the various stromal and immunological cell components of the tumor microenvironment (TME) crucially influences cancer progression and diversification, as well as endowing clinical and prognostic significance. The immunosuppression characterizing the TME depends on the recruitment and activation of different cell types including regulatory T cells, myeloid-derived suppressor cells, and tumor-associated macrophages. Less considered is the non-cellular component of the TME. Here, we focus on the extracellular matrix (ECM) regulatory activities that, within the TME, actively contribute to many aspects of tumor progression, acti…
Microenvironment-centred dynamics in aggressive B-cell lymphomas.
2012
Aggressive B-cell lymphomas share high proliferative and invasive attitudes and dismal prognosis despite heterogeneous biological features. In the interchained sequence of events leading to cancer progression, neoplastic clone-intrinsic molecular events play a major role. Nevertheless, microenvironment-related cues have progressively come into focus as true determinants for this process. The cancer-associated microenvironment is a complex network of nonneoplastic immune and stromal cells embedded in extracellular components, giving rise to a multifarious crosstalk with neoplastic cells towards the induction of a supportive milieu. The immunological and stromal microenvironments have been cl…
Defective stromal remodeling and neutrophil extracellular traps in lymphoid tissues favor the transition from autoimmunity to lymphoma
2013
Abstract Altered expression of matricellular proteins can become pathogenic in the presence of persistent perturbations in tissue homeostasis. Here, we show that autoimmunity associated with Fas mutation was exacerbated and transitioned to lymphomagenesis in the absence of SPARC (secreted protein acidic rich in cysteine). The absence of SPARC resulted in defective collagen assembly, with uneven compartmentalization of lymphoid and myeloid populations within secondary lymphoid organs (SLO), and faulty delivery of inhibitory signals from the extracellular matrix. These conditions promoted aberrant interactions between neutrophil extracellular traps and CD5+ B cells, which underwent malignant …
SPARC oppositely regulates inflammation and fibrosis in bleomycin-induced lung damage.
2011
Fibrosis results from inflammatory tissue damage and impaired regeneration. In the context of bleomycin-induced pulmonary fibrosis, we demonstrated that the matricellular protein termed secreted protein acidic and rich in cysteine (SPARC) distinctly regulates inflammation and collagen deposition, depending on its cellular origin. Reciprocal Sparc(-/-) and wild-type (WT) bone marrow chimeras revealed that SPARC expression in host fibroblasts is required and sufficient to induce collagen fibrosis in a proper inflammatory environment. Accordingly, Sparc(-/-) >WT chimeras showed exacerbated inflammation and fibrosis due to the inability of Sparc(-/-) macrophages to down-regulate tumor necrosis …
Mast Cells Infiltrating Inflamed or Transformed Gut Alternatively Sustain Mucosal Healing or Tumor Growth.
2015
Abstract Mast cells (MC) are immune cells located next to the intestinal epithelium with regulatory function in maintaining the homeostasis of the mucosal barrier. We have investigated MC activities in colon inflammation and cancer in mice either wild-type (WT) or MC-deficient (KitW-sh) reconstituted or not with bone marrow-derived MCs. Colitis was chemically induced with dextran sodium sulfate (DSS). Tumors were induced by administering azoxymethane (AOM) intraperitoneally before DSS. Following DSS withdrawal, KitW-sh mice showed reduced weight gain and impaired tissue repair compared with their WT littermates or KitW-sh mice reconstituted with bone marrow-derived MCs. MCs were localized i…
Cross-Talk between Myeloid-Derived Suppressor Cells and Mast Cells Mediates Tumor-Specific Immunosuppression in Prostate Cancer.
2018
Abstract Immunotherapy, including the use of checkpoint inhibitors, is a potent therapeutic approach for some cancers, but has limited success with prostate tumors, in which immune suppression is instigated by the tumor. The immunosuppressive capacity of mast cells, which promote adenocarcinoma development in the prostate, prompted our investigation on whether mast cells promote tolerance to SV40 Large-T antigen, the transforming oncogene in transgenic adenocarcinoma of the mouse prostate (TRAMP) mice. The incidence of adenocarcinoma was reduced in the offspring of a cross between TRAMP mice and mast cell–deficient KitWsh mice. TRAMP mice are tolerant to the SV40 Large T antigen, which is o…
Antibody–Fc/FcR Interaction on Macrophages as a Mechanism for Hyperprogressive Disease in Non–small Cell Lung Cancer Subsequent to PD-1/PD-L1 Blockade
2019
Abstract Purpose: Hyperprogression (HP), a paradoxical boost in tumor growth, was described in a subset of patients treated with immune checkpoint inhibitors (ICI). Neither clinicopathologic features nor biological mechanisms associated with HP have been identified. Experimental Design: Among 187 patients with non–small cell lung cancer (NSCLC) treated with ICI at our institute, cases with HP were identified according to clinical and radiologic criteria. Baseline histologic samples from patients treated with ICI were evaluated by IHC for myeloid and lymphoid markers. T-cell–deficient mice, injected with human lung cancer cells and patient-derived xenografts (PDX) belonging to specific mutat…
Nicotinamide Phosphoribosyltransferase Acts as a Metabolic Gate for Mobilization of Myeloid-Derived Suppressor Cells
2019
Abstract Cancer induces alteration of hematopoiesis to fuel disease progression. We report that in tumor-bearing mice the macrophage colony-stimulating factor elevates the myeloid cell levels of nicotinamide phosphoribosyltransferase (NAMPT), the rate-limiting enzyme in the NAD salvage pathway, which acts as negative regulator of the CXCR4 retention axis of hematopoietic cells in the bone marrow. NAMPT inhibits CXCR4 through a NAD/Sirtuin 1–mediated inactivation of HIF1α-driven CXCR4 gene transcription, leading to mobilization of immature myeloid-derived suppressor cells (MDSC) and enhancing their production of suppressive nitric oxide. Pharmacologic inhibition or myeloid-specific ablation …
Microenvironmental regulation of the IL-23R/IL-23 axis overrides chronic lymphocytic leukemia indolence
2018
Although the progression of chronic lymphocytic leukemia (CLL) requires the cooperation of the microenvironment, the exact cellular and molecular mechanisms involved are still unclear. We investigated the interleukin (IL)-23 receptor (IL-23R)/IL-23 axis and found that circulating cells from early-stage CLL patients with shorter time-to-treatment, but not of those with a more benign course, expressed a defective form of the IL-23R complex lacking the IL-12Rβ1 chain. However, cells from both patient groups expressed the complete IL-23R complex in tissue infiltrates and could be induced to express the IL-12Rβ1 chain when cocultured with activated T cells or CD40L+ cells. CLL cells activated in…
Additional file 1 of Intracellular osteopontin protects from autoimmunity-driven lymphoma development inhibiting TLR9-MYD88-STAT3 signaling
2023
Additional file 1. Supplementary file 1. Supplementary Material & methods.
Additional file 6 of Intracellular osteopontin protects from autoimmunity-driven lymphoma development inhibiting TLR9-MYD88-STAT3 signaling
2023
Additional file 6: Supplementary Figure S3. Immunohistochemistry staining of OPN IHC for OPN was performed in Fas lpr/lpr and OPN-/-Fas lpr/lpr mice with either no lymphoma or with lymphomatous cells. As expected, no staining is detected in case of OPN-deficient mice.
Additional file 4 of Intracellular osteopontin protects from autoimmunity-driven lymphoma development inhibiting TLR9-MYD88-STAT3 signaling
2023
Additional file 4: Supplementary Figure S1. Evaluation of autoimmunity in Faslpr/lpr and OPN-/-Faslpr/lpr mice. A. Quantification of OPN in sera from Faslpr/lpr mice at 2 (n=8) and 5 months of age (n=7) by ELISA. Sera from BALB/c and OPN-/- mice were tested as controls. Data are expressed as ng/ml and are a pool of 2 experiments (*, P<0.05; Ordinary one way ANOVA). B. Flow cytometry analysis showing the relative number of splenic autoimmune CD3+B220+ T cells in Faslpr/lpr (n=15) and OPN-/-Faslpr/lpr mice (n=18) and at about 5-6 months of age. The graph shows a pool of 3 different experiments (***, P<0.001; Student t test). C. Representative spleen photograph from BALB/c, OPN-/-, Faslp…
Additional file 7 of Intracellular osteopontin protects from autoimmunity-driven lymphoma development inhibiting TLR9-MYD88-STAT3 signaling
2023
Additional file 7: Supplementary Figure S4. Characterization of OPL239 and OPL241 DLBCL cell lines. A. Flow cytometry analysis showing the expression of B220, IgM, IgD and IgA in OPL239 and OPL241 cell lines. B. Hardy’s multiparametric flow cytometry panel illustrating the expression of CD93, CD21/35 and CD23 on OPL239 and OPL241 cell lines. C. Flow cytometry analysis showing the expression of TLR9 on OPL239 and OPL241 cell lines. D. RT-PCR analysis showing Spp1 mRNA level in overexpressing cell variants. E. Western blot for OPN protein expression (in presence or not of BFA, that blocks protein secretion) in parental and IRES-Green-based cell variants. 4T1 mammary cell line was used as posi…
SCD5-induced oleic acid production reduces melanoma malignancy by intracellular retention of SPARC and cathepsin B
2014
A proper balance between saturated and unsaturated fatty acids (FAs) is required for maintaining cell homeostasis. The increased demand of FAs to assemble the plasma membranes of continuously dividing cancer cells might unbalance this ratio and critically affect tumour outgrowth. We unveiled the role of the stearoyl-CoA desaturase SCD5 in converting saturated FAs into mono-unsaturated FAs during melanoma progression. SCD5 is down-regulated in advanced melanoma and its restored expression significantly reduced melanoma malignancy, both in vitro and in vivo, through a mechanism governing the secretion of extracellular matrix proteins, such as secreted protein acidic and rich in cysteine (SPAR…
Additional file 5 of Intracellular osteopontin protects from autoimmunity-driven lymphoma development inhibiting TLR9-MYD88-STAT3 signaling
2023
Additional file 5: Supplementary Figure S2. Evaluation of the different spenic B cell subsets. A. Example of Hardy’s gating strategy to discern the different CD93+ immature (Transitional T1, T2, T3) and CD93- mature [follicular B (FOB), marginal zone B (MZB) and CD21/35-CD23-] B cell subsets in the spleen from a BALB/c mouse. B. Flow cytometry analysis based on Hardy’s multiparametric panel illustrating the fraction of splenic CD23+ FOB, CD21/35+ MZB cells, and CD23-CD21/35- cells from the spleens of naive and autoimmune mice. 3 mice per group were used for the experiment. Data are referred to one representative experiment out of 3 (***, P<0.001; Two-way ANOVA) (****, P<0.0001; Two-wa…
Additional file 8 of Intracellular osteopontin protects from autoimmunity-driven lymphoma development inhibiting TLR9-MYD88-STAT3 signaling
2023
Additional file 8: Supplementary Figure S5. Expression of OPN in human GCB- and ABC-DLBCL samples. Immunohistochemistry analysis for OPN was performed on six cases for GCB- and ABC-DLBCLs. Representative images for two cases for each subtype are shown (quantification is shown in Figure 7B). Magnification 20X.
Additional file 2 of Intracellular osteopontin protects from autoimmunity-driven lymphoma development inhibiting TLR9-MYD88-STAT3 signaling
2023
Additional file 2: Supplementary Table S1. Differentially expressed genes between CD19+ cellsfrom OPN-/-Fas lpr/lpr and Faslpr/lpr mice.
Additional file 3 of Intracellular osteopontin protects from autoimmunity-driven lymphoma development inhibiting TLR9-MYD88-STAT3 signaling
2023
Additional file 3: Supplementary Table S2. Differentially expressed genes between CD19+ cellsfrom OPN-/-and OPN+/+ mice.