@article {1983, title = {The non-genotoxic activator of the p53 pathway Nutlin-3 shifts the balance between E2F7 and E2F1 transcription factors in leukemic cells.}, journal = {Invest New Drugs}, volume = {31}, year = {2013}, month = {2013 Apr}, pages = {458-60}, abstract = {

The effect of Nutlin-3, a small molecule inhibitor of the MDM2/p53 interaction, was investigated on the steady-state mRNA levels of the transcription factors E2F1 and E2F7 in a cohort of primary B-chronic lymphocytic leukemia (B-CLL) patient samples (n = 15) and normal peripheral blood mononuclear cells (PBMC). A 24-h treatment with Nutlin-3 significantly down-regulated E2F1 and promoted the concomitant up-regulation of E2F7 in both leukemic and normal cells. Our data suggest that the ability of Nutlin-3 to up-regulate E2F7 likely represents an important molecular determinant in the anti-proliferative activity of Nutlin-3.

}, keywords = {Case-Control Studies, Cells, Cultured, E2F1 Transcription Factor, E2F7 Transcription Factor, Gene Expression Regulation, Leukemic, Humans, Imidazoles, In Situ Hybridization, Fluorescence, Leukemia, Lymphocytic, Chronic, B-Cell, Leukocytes, Mononuclear, Piperazines, Real-Time Polymerase Chain Reaction, Reverse Transcriptase Polymerase Chain Reaction, RNA, Messenger, Tumor Suppressor Protein p53}, issn = {1573-0646}, doi = {10.1007/s10637-012-9882-y}, author = {di Iasio, Maria Grazia and Zauli, Giorgio} } @article {1769, title = {Activation of the p53 pathway induces α-smooth muscle actin expression in both myeloid leukemic cells and normal macrophages.}, journal = {J Cell Physiol}, volume = {227}, year = {2012}, month = {2012 May}, pages = {1829-37}, abstract = {

A range of cell types of mesenchymal origin express α-smooth muscle actin (α-SMA), a protein that plays a key role in controlling cell motility and differentiation along the fibrocyte and myofibroblast lineages. Although α-SMA is often expressed in stromal cells associated to a variety of cancers including hematological malignancies, up to now the role of anti-cancer drugs on α-SMA has not been deeply investigated. In this study, we demonstrated that Nutlin-3, the small molecule inhibitor of the MDM2/p53 interactions, significantly up-regulated the mRNA and protein levels of α-SMA in normal macrophages as well as in p53(wild-type) but not in p53(mutated/null) myeloid leukemic cells. The p53-dependence of α-SMA up-regulation induced by Nutlin-3 was demonstrated in experiments performed with siRNA for p53. Of note, Nutlin-3 mediated up-regulation of α-SMA in OCI leukemic cells was accompanied by cell adhesion to plastic substrate and by reduced cell migratory response in transwell assays. Notably, the role of α-SMA induction in the modulation of myeloid cell migration was clearly documented in α-SMA gene knockdown experiments. In addition, Nutlin-3 significantly up-regulated α-SMA expression in primary endothelial cells, but not in fibroblasts and mesenchymal stem cells (MSC). Conversely, transforming growth factor-β1 up-regulated α-SMA in fibroblasts and MSC, but not in macrophages and endothelial cells. Taken together, these data indicate that Nutlin-3 is a potent inducer of α-SMA in both normal and leukemic myeloid cells as well as in endothelial cells.

}, keywords = {Actins, Cell Movement, Cells, Cultured, Endothelial Cells, Fibroblasts, Humans, Imidazoles, Leukemia, Myeloid, Macrophages, Mesenchymal Stromal Cells, Piperazines, Proto-Oncogene Proteins c-mdm2, RNA, Small Interfering, Signal Transduction, Transforming Growth Factor beta1, Tumor Suppressor Protein p53}, issn = {1097-4652}, doi = {10.1002/jcp.22910}, author = {Secchiero, Paola and Rimondi, Erika and di Iasio, Maria Grazia and Voltan, Rebecca and Gonelli, Arianna and Zauli, Giorgio} } @article {1927, title = {Endothelial cells obtained from patients affected by chronic venous disease exhibit a pro-inflammatory phenotype.}, journal = {PLoS One}, volume = {7}, year = {2012}, month = {2012}, pages = {e39543}, abstract = {

BACKGROUND: The inflammatory properties of vein endothelium in relation to chronic venous disease (CVD) have been poorly investigated. Therefore, new insights on the characteristics of large vein endothelium would increase our knowledge of large vessel physiopathology.

METHODOLOGY/PRINCIPAL FINDINGS: Surgical specimens of veins were obtained from the tertiary venous network (R3) and/or saphenous vein (SF) of patients affected by CVD and from control individuals. Highly purified venous endothelial cell (VEC) cultures obtained from CVD patients were characterized for morphological, phenotypic and functional properties compared to control VEC. An increase of CD31/PECAM-1, CD146 and ICAM-1 surface levels was documented at flow cytometry in pathological VEC with respect to normal controls. Of note, the strongest expression of these pro-inflammatory markers was observed in VEC obtained from patients with more advanced disease. Similarly, spontaneous cell proliferation and resistance to starvation was higher in pathological than in normal VEC, while the migratory response of VEC showed an opposite trend, being significantly lower in VEC obtained from pathological specimens. In addition, in keeping with a higher baseline transcriptional activity of NF-kB, the release of the pro-inflammatory cytokines osteoprotegerin (OPG) and vascular endothelial growth factor (VEGF) was higher in pathological VEC cultures with respect to control VEC. Interestingly, there was a systemic correlation to these in vitro data, as demonstrated by higher serum OPG and VEGF levels in CVD patients with respect to normal healthy controls.

CONCLUSION/SIGNIFICANCE: Taken together, these data indicate that large vein endothelial cells obtained from CVD patients exhibit a pro-inflammatory phenotype, which might significantly contribute to systemic inflammation in CVD patients.

}, keywords = {Adult, Antigens, CD146, Antigens, CD31, Body Mass Index, Cell Culture Techniques, Endothelial Cells, Female, Flow Cytometry, Humans, Inflammation, Intercellular Adhesion Molecule-1, Kinetics, Male, Microscopy, Electron, Scanning, Middle Aged, Phenotype, Saphenous Vein, Vascular Diseases}, issn = {1932-6203}, doi = {10.1371/journal.pone.0039543}, author = {Tisato, Veronica and Zauli, Giorgio and Voltan, Rebecca and Gianesini, Sergio and di Iasio, Maria Grazia and Volpi, Ilaria and Fiorentini, Guido and Zamboni, Paolo and Secchiero, Paola} } @article {1738, title = {Hydrogen sulfide down-regulates the expression and release of osteoprotegerin (OPG) by vascular endothelial cells.}, journal = {Invest New Drugs}, volume = {30}, year = {2012}, month = {2012 Aug}, pages = {1731-5}, keywords = {Cell Death, Cytostatic Agents, Down-Regulation, Human Umbilical Vein Endothelial Cells, Humans, Hydrogen Sulfide, Osteoprotegerin, Tumor Necrosis Factor-alpha}, issn = {1573-0646}, doi = {10.1007/s10637-011-9675-8}, author = {Rimondi, Erika and di Iasio, Maria Grazia and Gonelli, Arianna and Celeghini, Claudio and Secchiero, Paola and Zauli, Giorgio} } @article {1766, title = {Nutlin-3 differentially modulates miRNA34a and miRNA181 versus miR26a and miR155 in p53 proficient and p53 deficient B chronic lymphocytic leukemia (B-CLL) samples.}, journal = {Invest New Drugs}, volume = {30}, year = {2012}, month = {2012 Aug}, pages = {1761-5}, keywords = {Down-Regulation, Gene Expression Profiling, Gene Expression Regulation, Leukemic, Humans, Imidazoles, Leukemia, Lymphocytic, Chronic, B-Cell, MicroRNAs, Piperazines, Proto-Oncogene Proteins c-mdm2, Tumor Suppressor Protein p53}, issn = {1573-0646}, doi = {10.1007/s10637-011-9695-4}, author = {di Iasio, Maria Grazia and Addobbati, Riccardo and Radillo, Oriano and Voltan, Rebecca} } @article {1903, title = {SOCS1 is significantly up-regulated in Nutlin-3-treated p53wild-type B chronic lymphocytic leukemia (B-CLL) samples and shows an inverse correlation with miR-155.}, journal = {Invest New Drugs}, volume = {30}, year = {2012}, month = {2012 Dec}, pages = {2403-6}, abstract = {

The basal SOCS1 mRNA levels were significantly lower in p53(mutated) BJAB and MAVER leukemic cell lines with respect to p53(wild-type) SKW6.4 and JVM-2 leukemic cell lines, p53(wild-type) primary B chronic lymphocytic leukemia (B-CLL) cells and primary normal peripheral blood mononuclear cells (PBMC). Moreover, the MDM2 small molecule inhibitor Nutlin-3 significantly increased the levels of SOCS1 mRNA in both primary p53(wild-type) B-CLL cells as well as in p53(wild-type) B leukemic cell lines, but not in p53(mutated) B leukemic cell lines nor in primary PBMC. Of note, a significant inverse correlation was observed between SOCS1 mRNA and miR-155 levels in Nutlin-3-treated primary B-CLL cells and PBMC, suggesting that the miRNA-155/SOCS1 axis represents a potentially important therapeutic target of Nutlin-3 in B-CLL.

}, keywords = {Cell Line, Tumor, Cells, Cultured, Down-Regulation, Humans, Imidazoles, Leukemia, Lymphocytic, Chronic, B-Cell, Leukocytes, Mononuclear, MicroRNAs, Piperazines, Suppressor of Cytokine Signaling Proteins, Tumor Suppressor Protein p53, Up-Regulation}, issn = {1573-0646}, doi = {10.1007/s10637-011-9786-2}, author = {di Iasio, Maria Grazia and Norcio, Alessia and Melloni, Elisabetta and Zauli, Giorgio} } @article {1926, title = {The sorafenib plus nutlin-3 combination promotes synergistic cytotoxicity in acute myeloid leukemic cells irrespectively of FLT3 and p53 status.}, journal = {Haematologica}, volume = {97}, year = {2012}, month = {2012 Nov}, pages = {1722-30}, abstract = {

BACKGROUND: Both the multi-kinase inhibitor sorafenib and the small molecule inhibitor of the MDM2/p53 interaction, nutlin-3, used alone, have shown promising anti-leukemic activity in acute myeloid leukemia cells. Thus, in this study we investigated the effect of the combination of sorafenib plus nutlin-3 in acute myeloid leukemia.

DESIGN AND METHODS: Primary acute myeloid leukemia blasts (n=13) and FLT3(wild-type)/p53(wild-type) (OCI-AML3), FLT3(mutated)/p53(wild-type) (MOLM), FLT3(mutated)/p53(mutated) (MV4-11), FLT3(wild-type)/p53(deleted) (HL60) or FLT3(wild-type)/p53(mutated) (NB4) acute myeloid cell lines were exposed to sorafenib, used alone or in association with nutlin-3 at a 1:1 ratio, in a range of clinically achievable concentrations (1-10 μM). Induction of apoptosis and autophagy was evaluated by transmission electron microscopy and by specific flow cytometry analyses. The levels of Mcl-1, p53 and Bak proteins were analyzed by western blotting. Knock-down of Bax and Bak gene expression was performed in transfection experiments with specific short interfering RNA.

RESULTS: The sorafenib+nutlin-3 drug combination exhibits synergistic cytotoxicity in primary acute myeloid leukemia blasts and in acute myeloid leukemia cell lines with maximal cytotoxicity in FLT3(mutated) MV4-11 and MOLM, followed by the FLT3(wild-type) OCI-AML3, HL60 and NB4 cell lines. The cytotoxic activity of sorafenib+nutlin-3 was characterized by an increase of both apoptosis and autophagy. Moreover, Bax and Bak showed prominent roles in mediating the decrease of cell viability in response to the drug combination in p53(wild-type) OCI-AML3 and p53(deleted) HL-60 cells, respectively, as demonstrated in transfection experiments performed with specific short interfering RNA.

CONCLUSIONS: Our data demonstrate that acute myeloid leukemia cells show a variable but overall good susceptibility to the innovative therapeutic combination of sorafenib+nutlin-3, which differentially involves the pro-apoptotic Bcl-2 family members Bax and Bak in p53(wild-type) and p53(deleted) cells.

}, keywords = {Antineoplastic Agents, Drug Synergism, Female, fms-Like Tyrosine Kinase 3, HL-60 Cells, Humans, Imidazoles, Leukemia, Myeloid, Acute, Male, Niacinamide, Phenylurea Compounds, Piperazines, Tumor Suppressor Protein p53}, issn = {1592-8721}, doi = {10.3324/haematol.2012.062083}, author = {Zauli, Giorgio and Celeghini, Claudio and Melloni, Elisabetta and Voltan, Rebecca and Ongari, Manuele and Tiribelli, Mario and di Iasio, Maria Grazia and Lanza, Francesco and Secchiero, Paola} } @article {1729, title = {miR-34a induces the downregulation of both E2F1 and B-Myb oncogenes in leukemic cells.}, journal = {Clin Cancer Res}, volume = {17}, year = {2011}, month = {2011 May 1}, pages = {2712-24}, abstract = {

PURPOSE: To elucidate new molecular mechanisms able to downregulate the mRNA levels of key oncogenes, such as B-Myb and E2F1, in a therapeutic perspective.

EXPERIMENTAL DESIGN: B-Myb and E2F1 mRNA levels were evaluated in primary B chronic lymphocytic leukemia (B-CLL, n = 10) and acute myeloid leukemia (AML, n = 5) patient cells, in a variety of p53(wild-type) and p53(mutated/deleted) leukemic cell lines, as well as in primary endothelial cells and fibroblasts. Knockdown experiments with siRNA for p53 and E2F1 and overexpression experiments with miR34a were conducted to elucidate the role of these pathways in promoting B-Myb downregulation.

RESULTS: In vitro exposure to Nutlin-3, a nongenotoxic activator of p53, variably downregulated the expression of B-Myb in primary leukemic cells and in p53(wild-type) myeloid (OCI, MOLM) and lymphoblastoid (SKW6.4, EHEB) but not in p53(mutated) (NB4, BJAB, MAVER) or p53(deleted) (HL-60) leukemic cell lines. The transcriptional repression of B-Myb was also observed in primary normal endothelial cells and fibroblasts. B-Myb downregulation played a critical role in the cell-cycle block in G(1) phase induced by Nutlin-3, as shown by transfection experiments with specific siRNA. Moreover, we have provided experimental evidence suggesting that miR-34a is a central mediator in the repression of B-Myb both directly and through E2F1.

CONCLUSIONS: Owing to the role of B-Myb and E2F1 transcription factors in controlling cell-cycle progression of leukemic cells, the downregulation of these oncogenes by miR-34a suggests the usefulness of therapeutic approaches aimed to modulate the levels of miR-34a.

}, keywords = {Base Sequence, Cell Cycle Proteins, Cell Line, Tumor, Cells, Cultured, Down-Regulation, E2F1 Transcription Factor, Gene Expression Regulation, Leukemic, HCT116 Cells, HL-60 Cells, Humans, Imidazoles, Leukemia, MicroRNAs, Models, Biological, Oncogenes, Piperazines, Sequence Homology, Nucleic Acid, Trans-Activators, Transfection}, issn = {1078-0432}, doi = {10.1158/1078-0432.CCR-10-3244}, author = {Zauli, Giorgio and Voltan, Rebecca and di Iasio, Maria Grazia and Bosco, Raffaella and Melloni, Elisabetta and Sana, Maria Elena and Secchiero, Paola} } @article {1817, title = {Trail down-regulates the release of osteoprotegerin (OPG) by primary stromal cells.}, journal = {J Cell Physiol}, volume = {226}, year = {2011}, month = {2011 Sep}, pages = {2279-86}, abstract = {

The soluble member of the TNF-R superfamily osteoprotegerin (OPG) is abundantly released under basal conditions by both mesenchymal stem cells (MSC) and fibroblasts and by endothelial cells upon stimulation with inflammatory cytokines. Since MSC, fibroblasts and endothelial cells represent key elements of the normal and tumor microenvironment and express detectable levels of surface TRAIL receptors, we investigated the effect of TRAIL on OPG release. Unexpectedly, recombinant TRAIL decreased the spontaneous OPG release in all cell types examined. Moreover, TRAIL decreased OPG release also in stromal cells co-cultured with lymphoma cells and counteracted the OPG induction by TN-alpha in HUVEC and MSC. Such down-regulation was not due to a masking effect in the ELISA quantification of the OPG released in the culture supernatants due to binding of OPG to its ligands (TRAIL and RANKL), as demonstrated by competition experiments with recombinant TRAIL and by the lack of RANKL release/induction. In addition, OPG down-regulation was not due to induction of cytotoxic effects by TRAIL, since the degree of apoptosis in response to TRAIL was negligible in all primary cell types. With regards to the possible molecular mechanism accounting for the down-regulation of OPG release by TRAIL, we found that treatment of MSC with TRAIL significantly decreased the phosphorylation levels of p38/MAPK. There is a suggestion that this pathway is involved in the stabilization of OPG mRNA. In this respect, the ability of TRAIL to decrease the release of OPG, in the absence of cell cytotoxicity, was mimicked by the p38/MAPK inhibitor SB203580.

}, keywords = {Bone Marrow Cells, Cell Death, Cells, Cultured, Coculture Techniques, Down-Regulation, Endothelial Cells, Enzyme Activation, Enzyme-Linked Immunosorbent Assay, Fibroblasts, Humans, MAP Kinase Signaling System, Mesenchymal Stromal Cells, Osteoprotegerin, p38 Mitogen-Activated Protein Kinases, Protein Binding, Recombinant Proteins, Stromal Cells, TNF-Related Apoptosis-Inducing Ligand, Tumor Necrosis Factor-alpha}, issn = {1097-4652}, doi = {10.1002/jcp.22564}, author = {Corallini, Federica and Celeghini, Claudio and Rimondi, Erika and di Iasio, Maria Grazia and Gonelli, Arianna and Secchiero, Paola and Zauli, Giorgio} } @article {1718, title = {Treatment with recombinant tumor necrosis factor-related apoptosis-inducing ligand alleviates the severity of streptozotocin-induced diabetes.}, journal = {Diabetes}, volume = {59}, year = {2010}, month = {2010 May}, pages = {1261-5}, abstract = {

OBJECTIVE: To evaluate the potential therapeutic effect of recombinant human tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) treatment in a model of type 1 diabetes.

RESEARCH DESIGN AND METHODS: Recombinant TRAIL was added in vitro to primary human and mouse peripheral blood mononuclear cells (PBMCs) and isolated human islets to evaluate the expression of the immunoregulatory gene SOCS1. Diabetes was induced by five consecutive daily injections of low-concentration (50 mg/kg) streptozotocin (STZ) in C57 black mice (n = 24). A group of these mice (n = 12) was co-injected with recombinant TRAIL (20 microg/day) for 5 days, and the diabetic status (glycemia and body weight) was followed over time. After 6 weeks, circulating levels of insulin, TNF-alpha, and osteoprotegerin (OPG) were measured, and animals were killed to perform the histological analysis of the pancreas.

RESULTS: The in vitro exposure of both PBMCs and human islets to recombinant TRAIL significantly upregulated the expression of SOCS1. With respect to STZ-treated animals, mice co-injected with STZ+TRAIL were characterized by 1) lower levels of hyperglycemia, 2) higher levels of body weight and insulinemia, 3) a partial preservation of pancreatic islets with normal morphology, and 4) a lower expression of both systemic (TNF-alpha and OPG) and pancreatic (vascular cell adhesion molecule [VCAM]-1) inflammatory markers.

CONCLUSIONS: Overall, these data demonstrate that the administration of recombinant TRAIL ameliorates the severity of STZ-induced type 1 diabetes, and this effect was accompanied by the upregulation of SOCS1 expression.

}, keywords = {Animals, Cells, Cultured, Diabetes Mellitus, Experimental, Gene Expression, Humans, Islets of Langerhans, Leukocytes, Mononuclear, Mice, Recombinant Proteins, Suppressor of Cytokine Signaling Proteins, TNF-Related Apoptosis-Inducing Ligand}, issn = {1939-327X}, doi = {10.2337/db09-1771}, author = {Zauli, Giorgio and Toffoli, Barbara and di Iasio, Maria Grazia and Celeghini, Claudio and Fabris, Bruno and Secchiero, Paola} }