0000000000017945
AUTHOR
Ivano Arioli
Abstract 2141: Stromal SPARC deficiency skews prostate cancer toward neuroendocrine differentiation
Abstract Tumor progression is a multifaceted process in which, complex interactions between tumor and different types of stromal cells and extracellular matrix components, actively contribute to its phenotypic heterogeneity. Among extracellular matrix proteins, secreted protein acidic and rich in cysteine (SPARC) has been deeply studied since conflicting reports have described its expression to be either increased or decreased in different cancer settings, also depending on whether it is produced by the neoplasm or by the neighboring stroma. Nevertheless, the different contribution of tumor- or stromal-derived SPARC in prostate tumor microenvironment has not been addressed at least for tumo…
Imatinib spares cKit-expressing prostate neuroendocrine tumors, whereas kills seminal vesicle epithelial-stromal tumors by targeting PDGFR-β
Abstract 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. Aiming at simultaneously targeting prostate NE tumor cells and MCs, both expressing the cKit tyrosine kinase receptor, we have tested the therapeutic effect of imatinib in TRAMP mice. Imatinib-treated TRAMP mice experience a pa…
Genetic deletion of osteopontin in TRAMP mice skews prostate carcinogenesis from adenocarcinoma to aggressive human-like neuroendocrine cancers
// 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…
Ultrasound-guided intra-tumor injection of combined immunotherapy cures mice from orthotopic prostate cancer.
Intra-tumor injection of immunotherapeutic agents is often the most effective, likely because of concomitant modification of tumor microenvironment. We tested an immunotherapeutic regimen consisting of CpG oligonucleotides and of adenovirus-mediated gene delivery of CCL16 chemokine directly into orthotopically implanted prostate tumors by ultrasound-guided injection, followed by systemic administration of an anti-IL-10R antibody. This combination treatment induced rapid stromal rearrangement, characterized by massive leukocyte infiltration and large areas of necrosis, a scenario that eventually led to complete tumor rejection and systemic immunity in 75 % of the treated mice. In vivo T lymp…
SPARC oppositely regulates inflammation and fibrosis in bleomycin-induced lung damage.
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 …