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Human exposures to environmental toxicants have been associated with etiology of many diseases including inflammation, cancer, and cardiovascular and neurodegenerative disorders. To counteract the detrimental effect of environmental insults, mammalian cells have evolved a hierarchy of sophisticated sensing and signaling mechanisms to turn on or off endogenous antioxidant responses accordingly. One of the major cellular antioxidant responses is the induction of antioxidative and carcinogen-detoxification enzymes through the cytoplasmic oxidative stress system (Nrf2-Keap1) activated by a variety of natural and synthetic chemopreventive agents. Under normal conditions, Keap1 anchors the Nrf2 transcription factor within the cytoplasm targeting it for ubiquitination and proteasomal degradation to maintain low levels of Nrf2 that mediate the constitutive expression of Nrf2 downstream genes. When cells are exposed to chemopreventive agents and oxidative stress, a signal involving phosphorylation and/or redox modification of critical cysteine residues in Keap1 inhibits the enzymatic activity of the Keap1-Cul3-Rbx1 E3 ubiquitin ligase complex, resulting in decreased Nrf2 ubiquitination and degradation. As a consequence, free Nrf2 translocates into the nucleus and in combination with other transcription factors (e.g., sMaf, ATF4, JunD, PMF-1) transactivates the antioxidant response elements (AREs)/electrophile response elements (EpREs) of many cytoprotective genes, as well as Nrf2 itself. Upon recovery of cellular redox homeostasis, Keap1 travels into the nucleus to dissociate Nrf2 from the ARE. Subsequently, the Nrf2-Keap1 complex is exported out of the nucleus by the nuclear export sequence (NES) in Keap1. Once in the cytoplasm, the Nrf2-Keap1 complex associates with the Cul3-Rbx1 core ubiquitin machinery, resulting in degradation of Nrf2 and termination of the Nrf2/ARE signaling pathway. The discovery of multiple nuclear localization signals (NLSs) and nuclear export signals (NESs) in Nrf2 also suggests that the nucleocytoplasm translocation of transcription factors is the consequence of a dynamic equilibrium of multivalent NLSs and NESs. On the other hand, Keap1 may provide an additional regulation of the quantity of Nrf2 both in basal and inducible conditions. This chapter summarizes the current body of knowledge regarding the molecular mechanisms through which ARE inducers (chemopreventive agents) regulate the coordinated transcriptional induction of genes encoding phase II and antioxidant enzymes as well as other defensive proteins, via the nuclear factor-erythroid 2 (NF-E2-p45)-related factor 2(Nrf2)/(ARE) signaling pathway.

WT1 gene is described to play an oncogenic role in a variety of tumours from different origins, including leukemias. In comparison to normal progenitor cells, it is overexpressed in acute lymphoblastic and myeloblastic leukemia, and in the blast crisis phase of chronic myelogenous leukaemia. Modulation of some members of the bcl-2 family has been associated with apoptosis inhibition by WT1. Among proteins that regulate apoptosis in leukemia cells, a role is assigned to BAG3, a member of the BAG family of co-chaperones. In this study we demonstrated that WT1 protein induces bag3 gene expression and that WT1- mediated increase in BAG3 protein levels contributes to the pro-survival role of WT1 in leukemic cells. The identification of bag3 as a target gene of WT1 improves our understanding of apoptosis regulation by this factor.

Laser-activated pyrolysis was applied to the synthesis of ultrafine TiO2, producing a non porous monocrystalline material in anatase phase with high specific surface area and uniform particle size. This powder was used as support for the preparation of vanadia catalysts with different compositions by wet impregnation. The pure TiO2 and the vanadia catalysts were characterized by X-ray diffraction, transmission electron microscopy, Fourier transform IR, X-ray photoelectron spectroscopy, ammonia temperature-programmed desorption and were tested in the reaction of nitric oxide reduction by ammonia. It has been proposed that two different VOx species formed in the submonolayer region: a VIV containing species which prevails up to 6 wt.-% V2O5 and a VV containing species which develops from 6 wt.-% V2O5 up to monolayer completion. The structure of these species has been hypothesized. A reaction scheme has been proposed to interpret the catalytic activity for the selective catalytic reduction (SCR) of NOx. The selectivity of catalysts for nitrogen is related to the prevalence of the VIV containing species.

Neoplasia pathogenesis and resistance to therapy are largely determined by acquired resistance to apoptosis. Among apoptosis- regulating molecules, a role is emerging for BAG3, a member of the BAG co-chaperone protein family. Through its bag, WW and prolix-rich domains, BAG3 protein can interact with a variety of molecular partners, including Hsc70/Hsp70, phospholipase C- gamma and others. It has been recently shown that, in human primary lymphoid and myeloblastic leukemias, thyroid carcinoma and other human tumours, BAG3 expression sustainscell survival and impairs cell response to therapy. Here we summarize findings that assign to BAG3 an anti-apoptotic role in some neoplastic cell types, in addition to other biological activities, and identify the protein as a candidate target of therapy.

Polyomavirus JC (JCV) infects oligodendrocytes and astrocytes in the brain and is the cause of the demyelinating disease progressive multifocal leukoencephalopathy (PML). In cell culture, JCV infection is characterized by severe damage to cellular DNA, which begins early in infection, and a viral cytopathic effect, which is observed late in infection. Nevertheless, these JCV-infected cells show a low level of apoptosis, at both the early and late stages of infection. This suggests that there is conflicting interplay between viral anti-apoptotic pathways that seek to optimize virus production, e.g. through T antigen (T-Ag)–p53 interaction, and cellular pro-apoptotic pathways that seek to eliminate virally infected cells. The apoptosis regulatory protein BAG3 is a member of the human Bcl-2-associated athanogene (BAG) family of proteins, which function as molecular co-chaperones through their interaction with Hsc70/Hsp70 and function in the regulation of the cellular stress response, proliferation and apoptosis. This study showed that BAG3 protein is downregulated upon JCV infection and that this effect is mediated by JCV T-Ag via repression of the BAG3 promoter. The site of action of T-Ag was mapped to an AP2 site in the BAG3 promoter, and gel shift and chromatin immunoprecipitation assays showed that T-Ag inhibited AP2 binding to this site, resulting in downregulation of BAG3 promoter expression. Using BAG3 and T-Ag expression and BAG3 siRNA, it was found that BAG3 and T-Ag had antagonistic effects on the induction of apoptosis, being anti-apoptotic and pro-apoptotic, respectively. The significance of these interactions to the JCV life cycle is discussed.

Deregulation of apoptosis is responsible for diseases that involve defects in the death pathway, such as neoplasias, or in its inhibition, like degenerative processes. Among apoptosis- regulating molecules, a role is emerging for BAG3, a member of the BAG proteins family (BAG1L, BAG1, BAG2, BAG3, BAG4. BAG5 and BAG6) involved in cochaperoning of heat shock proteins. Through its BAG, WW and prolix-rich domains, BAG3 protein can interact with a variety of molecular partners, including Hsc70/Hsp70, phospholipase C-γ and others. It has been recently shown that, in human primary lymphoid and myeloblastic leukemias, thyroid carcinoma and other human tumors, BAG3 expression sustains cell survival and impairs cell response to therapy. This review discusses two patents concerning, respectively, BAG3 and other Hsc70/Hsp70 co-chaperones, namely HspBP-1 and HspBP-2.

Soluble anti-HLA class I monoclonal antibodies (MoAbs) modulate normal T-lymphocyte proliferation induced via the CD3/Ti and the CD2 pathway, but do not induce proliferation of normal T lymphocytes in the absence of additional mitogenic stimuli. In this report, we show that anti-HLA class I MoAbs induce DNA synthesis in peripheral blood mononuclear cells from a patient with a CD4+CD8+T-prolymphocytic leukemia (T-PLL) and from a patient with a CD4-CD8+ T-chronic lymphocytic leukemia (T- CLL), in the absence of detectable additional mitogenic stimuli. Proliferation of leukemic T cells is induced by both whole Igs and Fab' fragments of anti-HLA class I MoAbs, arguing in favor of their direct interactions with the proliferating cells as the mechanism underlying the mitogenic effect. This interpretation is also supported by the ability of anti-HLA class I MoAbs to induce proliferation of leukemic T- cell preparations, depleted of accessory cells. DNA synthesis in T-CLL and T-PLL cells is preceded by expression of G1-specific messenger RNAs, ie. c-myc, 2F1, Tac, and interferon-gamma, in activated cells. Cell proliferation is inhibited by the protein kinase C inhibitor H7, indicating that activation of this enzyme is required for the mitogenic effect of anti-HLA class I MoAbs. The latter inhibit the proliferation of T-CLL cells as well as that of normal T cells stimulated with anti- CD3 MoAbs and enhance that of both types of cells stimulated with anti- CD2 MoAbs. In addition, anti-HLA class I MoAb Q6/64 in combination with anti-CD2 MoAb 9.6 or MoAb 9–1 induces proliferation of leukemic T cells to a greater extent than the individual MoAbs, but is not mitogenic for normal T cells. Anti-HLA class I MoAbs restore the cytolytic activity of T-CLL cells that is lost after 5 days of incubation of control medium, suggesting that HLA class I antigens may mediate a signal contributing to the activation state. The present results indicate that leukemic T-cell proliferation can be triggered via HLA class I molecules and suggest a potential role for these antigens in the in vivo growth of malignant clones.

The up-regulation of ferritin heavy chain (FHC) is reported in six papillary and in four invasive urothelial tumours of the urinary bladder of cattle grazing on mountain pastures rich in bracken fern. All tumours contained sequence of bovine papillomavirus type-2 (BPV-2) as determined by polymerase chain reaction (PCR) analyses and validated by direct sequencing of the amplified products. The oncoprotein E5 was also detected in these tumours by immunoprecipitation and by immunofluorescence and laser scanning confocal microscopy. Expression of FHC was evaluated by western blot analysis, reverse transcriptase (RT) PCR, real-time RT-PCR and immunohistochemistry. The oligonucleotide sequence of the bovine ferritin amplicons was identical to that of human ferritin. Nuclear overexpression of p65, an important component of nuclear factor kappaB (NF-kappaB) transcription factors, was also observed. These findings suggest that FHC up-regulation may be mediated by activation of NF-kappaB and that in turn this may be related to the resistance of bovine papillomavirus type-2 (BPV-2) infected urothelial cells to apoptosis.

The co-chaperone protein, BAG3, which belongs to the BAG protein family, has an established antiapoptotic function in different tumor cell lines. Here we demonstrated that treatment of the human neuroblastoma cell line, SK-N-MC, with fibroblast growth factor-2 (FGF-2) results in induction of BAG3 expression. Induction of BAG3 protein by FGF-2 occurs at the transcriptional level; it requires the extracellular regulated kinase1/2 pathway and is dependent on the activity of Egr-1 upon the BAG3 promoter. Targeted suppression of BAG3 by small-interfering RNA results in dysregulation of cell-cycle progression most notably at S and G(2) phases, which corroborates the decreased level of cyclin B1 expression. These observations suggest a new role for BAG3 in regulation of the cell cycle.

BAG3 protein, a member of the BAG co-chaperones family, sustains cell survival, through its interaction with the heat shock protein (HSP) 70, in a variety of normal and neoplastic cell types. bag3 gene expression is induced by stressful stimuli. Here we report for the first time that two of the three putative heat shock-responsive elements (HSEs) in bag3 promoter interact with the heat shock factor (HSF) 1 in vitro and in vivo. Furthermore, downmodulation of HSF1 protein levels by specific small interfering (si) RNAs results in reducing BAG3 protein levels, indicating that the transcription factor plays a major role in bag3 gene expression. Because of the anti-apoptotic role of BAG3 protein, these results disclose a previously unrecognized pathway, through which HSF1 maintains cell survival.

A mesoporous Cu-Ce-Al-based material was prepared by a single-step synthesis, performed in n -propanol using aluminum sec -butoxide as Al precursor and metal stearates, both as Cu-Ce sources and structural directing agents. This type of synthetic approach appears to be very efficient for the preparation of highly dispersed Cu-Ce containing particles supported on a structurally ordered alumina with high surface area (>400 m 2 g −1 ) and quite narrow pore size distribution, as confirmed by X-ray powder diffraction, TPR and dispersion data and N 2 physisorption. The catalyst was also characterized by XPS and FT-IR measurements of adsorbed CO. The catalytic activity for the preferential oxidation of CO to CO 2 (PROX) in H 2 -rich streams was tested in the 75–200 °C temperature range.

Niobium–silicon mixed oxide nanocomposites, containing 7–37 wt.% Nb, were synthesized by a new sol–gel route and characterized for textural and acid properties by N 2 adsorption, NH 3 TPD and FTIR of adsorbed acetonitrile. The materials were tested as catalysts for epoxidation of cyclooctene with H 2 O 2 . High surface areas (>150 m 2 g −1 ), decreasing with Nb content, were found for materials containing up to 23.0 wt.% Nb. FTIR and TPD measurements evidenced the presence of both Bronsted and Lewis acid sites with different strength. The amount of strong acid sites, relative to those of low or moderate strength, increased with Nb content. The materials containing up to 23.0 wt.% Nb were active and stable catalysts for the epoxidation of cyclooctene. The highest activity and H 2 O 2 selectivity was found for the catalyst with the lowest Nb content, that showed also high stability in reuse. Catalytic properties were related to acid sites and to the presence of NbO x species with different coordination.

Gels of exfoliated alpha-zirconium phosphate (ZrPexf) in dimethylformamide (DMF) were used to prepare Nafion/ZrPexf composite membranes with filler loadings up to 7 wt% by casting mixtures of Nafion 1100 solutions in DMF and suitable amounts of 2 wt% ZrP gels in DMF. TEM pictures showed that the ZrPexf particles had aspect ratio of at least 20. All samples were characterised by methanol permeability (P) and through-plane (sigmathp) and in-plane (sigmainp) conductivity measurements at 40°C and 100% RH. The methanol permeability of Nafion membranes containing in situ grown ZrP particles with low aspect ratio (Nafion/ZrPisg) was also determined. The methanol permeability and the swelling behaviour of the composite membranes turned to be strongly dependent on the filler morphology. As a general trend both permeability and swelling decreased according to the sequence: Nafion/ZrPisg > Nafion > Nafion/ZrPexf. The maximum selectivity (P/sigmathp = 140000 S cm-3 s) was found for the membrane filled with 1 wt% ZrPexf: this value is 7 times higher than that of Nafion. For the Nafion/ZrPexf membranes the ratio sigmainp /sigmathp increases with the filler loading thus indicating that the preferred orientation of the ZrP sheets is parallel to the membrane surface

The acid properties of layered Me phosphates (MeTi, Ge, Zr, Sn) were determined by NH3 temperature-programmed desorption. Careful establishment of the preheating conditions suppressed interference from NH3 intercalation and allowed the surface acidity to be measured. A scale of acidity strength in line with the catalytic behaviour of these phosphates in acid-catalysed reactions was obtained.

Gloriosaols A-C, isolated from Yucca gloriosa (Agavaceae), are novel phenolic compounds structurally related to resveratrol. In the present study, we show that gloriosaols possess antiproliferative and pro-apoptotic activity on tumor cells of different histogenetic origin and that their cell growth inhibition potential is higher than that of resveratrol. Despite the close similarities in their structure, gloriosaols A-C exhibited different antiproliferative potency, as the EC(50) ascending order is: gloriosaol C, gloriosaol A, gloriosaol B. Further mechanisms of gloriosaol C cytotoxicity were elucidated in detail in U937 cells, the most sensitive of the cell lines tested. The effect of gloriosaol C on cell growth turned out to be strongly dependent upon the concentration. Gloriosaol C doses lower than the EC(50) value (8 mu-icroM) blocked the cell cycle in G(0)/G(1), with a concurrent decrease in the number of cells in the G(2)/M phases of the cell cycle. At higher doses, this arrest overlaps with the occurrence of apoptosis and necrosis. In the 10-25 microM range of doses, gloriosaol C caused cell death mainly by apoptosis, as measured by hypodiploidia induction, phosphatidyl serine externalization and disruption of mitochondrial transmembrane potential. A switch in the mode of death from apoptosis to necrosis occurred at doses of gloriosaol C higher than 30 microM. Gloriosaol C was found to induce production of reactive species dose-dependently, but also to counteract their elevation in stressed cells. Thus, the different fate of cells, that is cell cycle arrest or cell death, in response to different doses of gloriosaol C might be related to the extent of induced oxidative stress.

A family of co-chaperone proteins that share the Bcl-2-associated athanogene (BAG) domain are involved in a number of cellular processes, including proliferation and apoptosis. Among these proteins, BAG3 has received increased attention due to its high levels in several disease models and ability to associate with Hsp70 and a number of other molecular partners. BAG3 expression is stimulated during cell response to stressful conditions, such as exposure to high temperature, heavy metals, and certain drugs. Here, we demonstrate that BAG3 expression is elevated upon HIV-1 infection of human lymphocytes and fetal microglial cells. Furthermore, BAG3 protein was detectable in the cytoplasm of reactive astrocytes in HIV-1-associated encephalopathy biopsies, suggesting that induction of BAG3 is part of the host cell response to viral infection. To assess the impact of BAG3 upregulation on HIV-1 gene expression, we performed transcription assays and demonstrated that BAG3 can suppress transcription of the HIV-1 long terminal repeat (LTR) in microglial cells. This activity was mapped to the κB motif of the HIV-1 LTR. Results from in vitro and in vivo binding assays revealed that BAG3 suppresses interaction of the p65 subunit of NF-κB with the κB DNA motif of the LTR. Results from binding and transcriptional assay identified the C-terminus of BAG3 as a potential domain involved in the observed inhibitory effect of BAG3 on p65 activity. These observations reveal a previously unrecognized cell response, that is, an increase in BAG3, elicited by HIV-1 infection, and may provide a new avenue for the suppression of HIV-1 gene expression. J. Cell. Physiol. 210: 676–683, 2007. © 2006 Wiley-Liss, Inc.

Cu/ZnO/Al2O3 catalysts (5–45 Cu at.%) derived from layered double hydroxide (LDH) precursors were studied for oxidative steam reforming of methanol (OSRM). The precursors were prepared by homogeneous precipitation with urea. The catalysts were obtained by thermal decomposition of the precursors and subsequent reduction in H2 stream. XRD, SEM, N2 adsorption, TPR and NH3 TPD techniques were employed for characterization. Catalytic activity tests were carried out in a fixed bed flow reactor at T = 200–400 8C, H2O/CH3OH/O2 molar ratios = 1.1/1/0.12 (CH3OH concentration = 17.8%), GHSV = 6 � 10 4 h � 1 . Tests of simple steam reforming (SRM), partial oxidation (POM) and CH3OH decomposition (DEC) were also carried out. TPR measurements showed that redox properties depended on the composition of the samples and on the nature of the phases present in the precursors. The area of metallic Cu, measured by N2O passivation method, was correlated to Cu content. The size of Cu particles was smaller than 10 nm for Cu content up to 18 at.%. NH3 TPD measurements showed acid sites with a wide strength distribution, the strongest ones being mainly related to Al2O3 or Zn aluminate. Catalytic activity was influenced by the chemical composition: kinetic constants for OSRM varied unevenly with Cu surface area, while those for SRM increased with Cu surface area. A reaction mechanism agreeing with OSRM, SRM and DEC data was hypothesized. The mechanism involved an oxidation-reduction cycle of Cu and also the participation of the oxide matrix. # 2007 Elsevier B.V. All rights reserved.

Stress-induced apoptosis regulates neoplasia pathogenesis and response to therapy. Indeed, cell transformation induces a stress response, that is overcome, in neoplastic cells, by alterations in apoptosis modulators; on the other hand, antineoplastic therapies largely trigger the apoptosis stress pathway, whose impairment results in resistance. Therefore, the study of the roles of apoptosis-modulating molecules in neoplasia development and response to therapy is of key relevance for our understanding of these processes. Among molecules that regulate apoptosis, a role is emerging for BAG3, a member of the BAG co-chaperone protein family. Proteins that share the BAG domain are characterized by their interaction with a variety of partners (heat shock proteins, steroid hormone receptors, Raf-1 and others), involved in regulating a number of cellular processes, including proliferation and apoptosis. BAG3, also known as CAIR-1 or Bis, forms a complex with the heat shock protein (Hsp) 70. This assists polypeptide folding, can mediate protein delivery to proteasome and is able to modulate apoptosis by interfering with cytochrome c release, apoptosome assembly and other events in the death process. It has been recently shown that, in human primary lymphoid and myeloblastic leukemias and other neoplastic cell types, BAG3 expression sustains cell survival and underlies resistance to therapy, through downmodulation of apoptosis. This review summarizes findings that assign an apoptotic role to BAG3 in some neoplastic cell types and identify the protein as a candidate target of therapy.

Context: We previously showed that BAG3 protein, a member of the BAG (Bcl-2-associated athanogene) co-chaperone family, modulates apoptosis in human leukemias. The expression of BAG3 in other tumor types has not been extensively investigated so far. Objective: The objective of this study was to analyze BAG3 expression in thyroid neoplastic cells and investigate its influence in cell apoptotic response to TNF-related apoptosis-inducing ligand (TRAIL). Design, Setting, and Patients: We investigated BAG3 expression in human thyroid carcinoma cell lines, including NPA, and the effect of BAG3-specific small interfering RNA on TRAIL-induced apoptosis in NPA cells. Subsequently, we analyzed BAG3 expression in 30 benign lesions and 56 carcinomas from patients of the Naples Tumor Institute Fondazione Senatore Pascale. Main Outcome Measures: The main outcome measures were: analysis of BAG3 protein in NPA cells by Western blot and immunocytochemistry; analysis of apoptosis in TRAIL-stimulated NPA cells by flow cytometry; and evaluation of BAG3 expression in specimens from thyroid lesions by immunohistochemistry. Results: BAG3 was expressed in human thyroid carcinoma cell lines; small interfering RNA-mediated downmodulation of its levels significantly (P < 0.0195) enhanced NPA cell apoptotic response to TRAIL. The protein was not detectable in 19 of 20 specimens of normal thyroid or goiters, whereas 54 of 56 analyzed carcinomas (15 follicular, 28 papillary, and 13 anaplastic) were clearly positive for BAG3 expression. Conclusions: BAG3 downmodulates the apoptotic response to TRAIL in human neoplastic thyroid cells. The protein is specifically expressed in thyroid carcinomas and not in normal thyroid tissue or goiter.

Interactions between cancer cells and stromal cells are critically involved in tumor formation, progression and development of metastasis. Here we report for the first time that human pancreatic adenocarcinoma (PDAC) cells secrete BAG3 that binds and activates macrophages, inducing their activation and the secretion of pancreatic cancer- supporting factors. We also identify IFITM-2 as a BAG3 receptor, by its co-precipitation with BAG3 from macrophage cell membrane and by impairment of BAG3- induced activation in IFITM-2- silenced macrophages. Finally we show the importance of this pathway in vivo since in nu/nu mice carrying orthotopic xenografts of human PDAC (MIA PaCa-2) cells, BAG3 sequestration by an anti-BAG3 antibody results in reduced tumor growth and prevents metastastasis formation. In conclusion we have identified a novel paracrine loop involved in PDAC growth and metastatic spreading and shown that its pharmacological blockage with an anti-BAG3 antibody has therapeutic potential. Citation Format: Alessandra Rosati, Anna Basile, Raffaella D'Auria, Morena d'Avenia, Margot De Marco, Antonia Falco, Michelina Festa, Luana Guerriero, Vittoria Iorio, Maria Pascale, Renato Franco, Claudio Arra, Antonio Barbieri, Domenica Rea, Giulio Menichini, Michael Hahne, Marteen Bijlsma, Daniela Barcaroli, David A. Tuveson, Jelena Todoric, Michael Karin, Vincenzo De Laurenzi, Maria Caterina Turco. PDAC cells release BAG3 that activates a paracrine loop with stromal macrophages. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2393. doi:10.1158/1538-7445.AM2015-2393

We investigated the effects of 1-methoxy-canthin-6-one, isolated from the medicinal plant Ailanthus altissima Swingle, on apoptosis in human leukemia (Jurkat), thyroid carcinoma (ARO and NPA), and hepatocellular carcinoma (HuH7) cell lines. Cultures incubated with the compound showed >50% of sub-G1 (hypodiploid) elements in flow cytometry analysis; the apoptosis-inducing activity was evident at 80% prevented by the addition of the JNK inhibitor (JNKI) SP600125JNKI, indicating that both effects were almost completely mediated by JNK activity. On the other hand, synergism with TRAIL was reduced by about 50%, suggesting that besides up-regulating TRAIL-R1, 1-methoxy-canthin-6-one could influence other factor(s) that participated in TRAIL-induced apoptosis. These findings indicate that 1-methoxy-canthin-6-one can represent a candidate for in vivo studies of monotherapies or combined antineoplastic therapies. (Cancer Res 2006; 66(8): 4385-93)

The fully human anti-HLA-DR antibody 1D09C3 has been shown to delay lymphoma cell growth in severe combined immunodeficient (SCID) mice. The present study was aimed at (a) investigating the mechanism(s) of 1D09C3-induced cell death and (b) further exploring the therapeutic efficacy of 1D09C3 in nonobese diabetic (NOD)/SCID mice. The chronic lymphocytic leukemia cell line JVM-2 and the mantle cell lymphoma cell line GRANTA-519 were used. Generation of reactive oxygen species (ROS) and mitochondrial membrane depolarization were measured by flow cytometry following cell incubation with dihydroethidium and TMRE, respectively. Western blot analysis was used to detect c-Jun-NH2-kinase (JNK) phosphorylation and apoptosis-inducing factor (AIF). NOD/SCID mice were used to investigate the activity of 1D09C3 in early- or advanced-stage tumor xenografts. In vitro, 1D09C3-induced cell death involves a cascade of events, including ROS increase, JNK activation, mitochondrial membrane depolarization, and AIF release from mitochondria. Inhibition of JNK activity significantly reduced 1D09C3-induced apoptosis, indicating that 1D09C3 activity involves activation of the kinase. In vivo, 1D09C3 induces long-term disease-free survival in a significant proportion of tumor-bearing mice treated at an early stage of disease. Treatment of mice bearing advanced-stage lymphoma results in a highly significant prolongation of survival. These data show that 1D09C3 (a) exerts a potent antitumor effect by activating ROS-dependent, JNK-driven cell death, (b) cures the great majority of mice treated at an early-stage of disease, and (c) significantly prolongs survival of mice with advanced-stage disease. (Cancer Res 2006; 66(3): 1799-808)

Catalysts for oxidative methanol reforming were prepared by thermal and H 2 -reduction treatments of a precursor consisting mainly of a hydrotalcite-like Cu–Zn–Al hydroxycarbonate and a Zn-rich paratacamite. The precursor was obtained by homogeneous precipitation of metal cations with a properly modified urea method. XRPD and quantitative Rietveld analysis of the precursor material revealed the presence of hydrotalcite and paratacamite phases in a weight ratio 3:1. Treatment in situ of the precursor produced Cu/ZnO/Al 2 O 3 (Cu = 18%, Zn = 33%, Al = 49% mol) catalysts. Chemical properties of the precursor and of the catalysts were studied by TPR, TPO, NH 3 -TPD, N 2 O chemisorption, FTIR, and UV–vis techniques. Physical characterization was carried out by the SEM, EDS, XRPD, TG/DTA, and N 2 adsorption techniques. The influence of heating rate of the precursor was investigated. Heat-treated samples contained CuO, ZnO, and amorphous Al 2 O 3 , and probably ZnAl 2 O 4 , as suggested by XRPD and FTIR measurements. The crystallinity of oxide phases was higher for the sample treated with a lower heating rate that also showed lower surface area and lower Cu dispersion. The presence of Cu 2+ in octahedral sites of alumina was suggested by UV–vis spectra. CO adsorption gave evidence of easy reduction of Cu(II) to Cu(I) and Cu(0) and the formation of stable complexes with Cu(I). NH 3 -TPD and FTIR measurements showed the presence of surface acid sites of the Lewis type with wide strength distributions, mainly due to Zn 2+ and Al 3+ cations. Cu(II) was able to oxidize NH 3 , while Cu(0) activated NH 3 decomposition. TPR and TPO measurements indicated that Cu species are easily reduced and reoxidized and Cu(I) species are intermediate for both processes. The redox properties appeared to be influenced by the rate of the previous heat treatment.

Quassinoids can induce mitochondrial membrane depolarisation and caspase 3 activation in human cells

Pathways that regulate the activation of NF-κB/Rel transcription factors are known to include signaling through a number of cytokine receptors. Interleukin 7 (IL-7), produced by bone marrow and other stromal cells, is a key factor for differentiation and survival in the lymphoid and other compartments. We found that human recombinant IL-7 induced NF-κB/Rel activation, analyzed by electrophoretic mobility shift assay (EMSA), in human peripheral blood T lymphocytes from healthy donors. Induced complexes included p65 and p50 NF-κB/Rel subunits. These results demonstrate for the first time that IL-7 can participate in signaling leading to NF-κB/Rel activation.

Cu/ZnO/Al2O3 catalysts derived from a hydrotalcite precursor were studied for oxidative steam reforming of methanol (OSRM), with O2:H2O:CH3OH molar ratios = 0.12:1.1:1. The results were compared with those obtained in nonoxidative steam reforming (SRM) and in partial oxidation (POM) of methanol. The catalysts were highly active for OSRM, giving total CH3OH conversion at 350–400 °C with GHSV = 0.6 – 1.2 × 10 5 h − 1 . They also showed high selectivity, giving H2 yield of 2.5 mol per mole CH3OH, with CO concentration below 500 ppm. Besides the main products, CH2O and (CH3)2O were also observed at all temperatures, while some CH4 was produced at T > 300 °C . The catalytic activity increased with increasing heating rate of the catalyst precursor. High selectivity was observed also in SRM, but with lower conversion. On the other hand, POM appeared faster than SRM, but produced CO concentrations of a few percent at T > 300 °C , due to CH3OH decomposition. The production of CO was strongly reduced in the presence of water vapor. The reaction network was described in detail. The interaction methanol catalyst was studied by IR spectroscopy. IR spectra showed the presence of adsorbed methoxy groups, that were converted into formate groups at high temperature, and then decomposed into H2 and CO in the absence of O2 and/or H2O, while in their presence CO was probably oxidized to CO2 before desorption, due to the action of Cu(II) species.

BAG3 protein can influence the activity of more than one factor involved in the apoptotic process in human leukemia, and might in this respect constitute a versatile tool to target apoptosis.

High-mobility group A (HMGA) proteins are non-histone nuclear proteins that bind DNA and several transcription factors. They are involved in the regulation of chromatin structure and function. HMGA protein expression is low in normal adult tissues, but abundant during embryonic development and in several human tumours. Rearrangements of the HMGA genes have been frequently detected in human benign tumours of mesenchymal origin, e.g. lipomas, lung hamartomas and uterine leiomiomas. HMGA proteins have been implicated in the control of cell growth and differentiation of the pre-adipocytic cell line 3T3-L1. In an attempt to better understand the role of HMGA1 proteins in haematological neoplasias and in the differentiation of haematopietic cells, we have investigated their expression in human leukaemias and in leukaemic cell lines induced to terminal differentiation. Here we report HMGA1 overexpression in most fresh human leukaemias of different origin and in several leukaemic cell lines. Moreover, differentiation of three cell lines towards the megakaryocytic phenotype was associated with HMGA1 protein induction, whereas induction of erythroid and monocytic differentiation generally resulted in reduced HMGA1 expression.

In the present work we analyzed the proliferative response of T lymphocytes from 11 atopic patients stimulated in vitro via either the CD2 or the CD3 pathway of cell activation. In both cases we found a significant decrease of thymidine incorporation in cell DNA in comparison with T cells from normal donors. The mechanism of this impaired proliferative response was analyzed. Atopic patients' T cells were found to secrete low quantities of interleukin 2 (IL2) and to express low amounts of Tac antigen, measured as both a percentage of Tac-positive cells and a mean fluorescence intensity of Tac antigen per cell. Addition of recombinant IL2 to cultures completely restored both cell proliferative response and Tac antigen expression. This effect was specific of IL2 since addition of IL1 or IL4 did not significantly affect T cell proliferative response. We conclude that atopic patients' T lymphocytes have a defect in both CD2 and CD3 pathways of cell activation relying on impairment of IL2 production, without involving IL2 responsiveness or other lymphokine defects.

CD40-CD154 interactions play a key role in regulating immune response and are involved in the development of some autoimmune diseases. We analysed the expression of CD154 antigen in CD3-activated PBMC from 10 systemic sclerosis (SSc) patients and 10 control subjects by immunofluorescence. PBMC from SSc patients showed an increased expression of this molecule, since, 6 h following CD3 stimulation, the percentage of CD154(+)cells was of 17. 53+/-2.0 (mean+/-SE) in control and 25.33+/-2.93 in patient cells (P0.03). The higher expression of CD154 antigen was ascribible to CD4(+)cells. The enhanced induction of CD154 following CD3 stimulation depended on protein synthesis, since was abolished when the cells were stimulated via CD3 in the presence of cycloheximide. By analysing the expression of the CD40-induced antigen CD80, we verified that a blocking anti-CD40 antibody inhibited CD80 appearance in SSc activated monocytes, indicating that CD154 molecule was functional. These results show an enhanced expression of a functional CD154 molecule in SSc CD4(+)activated T lymphocytes.

Catalytic combustion of methane has been investigated over AMnO3 (A = La, Nd, Sm) and Sm1−xSrxMnO3 (x = 0.1, 0.3, 0.5) perovskites prepared by citrate method. The catalysts were characterized by chemical analysis, XRD and TPR techniques. Catalytic activity measurements were carried out with a fixed bed reactor at T = 623–1023 K, space velocity = 40 000 N cm3 g−1 h−1, CH4 concentration = 0.4% v/v, O2 concentration = 10% v/v. Specific surface areas of perovskites were in the range 13–20 m2 g−1. XRD analysis showed that LaMnO3, NdMnO3, SmMnO3 and Sm1−xSrxMnO3 (x = 0.1) are single phase perovskite type oxides. Traces of Sm2O3 besides the perovskite phase were detected in the Sm1−xSrxMnO3 catalysts for x = 0.3, 0.5. Chemical analysis gave evidence of the presence of a significant fraction of Mn(IV) in AMnO3. The fraction of Mn(IV) in the Sm1−xSrxMnO3 samples increased with x. TPR measurements on AMnO3 showed that the perovskites were reduced in two steps at low and high temperature, related to Mn(IV) → Mn(III) and Mn(III) → Mn(II) reductions, respectively. The onset temperatures were in the order LaMnO3 > NdMnO3 > SmMnO3. In Sm1−xSrxMnO3 the Sr substitution for Sm caused the formation of Mn(IV) easily reducible to Mn(II) even at low temperature. Catalytic activity tests showed that all samples gave methane complete conversion with 100% selectivity to CO2 below 1023 K. The activation energies of the AMnO3 perovskites varied in the same order as the onset temperatures in TPR experiments suggesting that the catalytic activity is affected by the reducibility of manganese. Sr substitution for Sm in SmMnO3 perovskites resulted in a reduction of activity with respect to the unsubstituted perovskite. This behaviour was related to the reduction of Mn(IV) to Mn(II), occurring under reaction conditions, hindering the redox mechanism.

The compound [Fe(H2O)]0.20(VO)0.80PO4 was studied for NH3-adsorption properties and catalytic activity towards NO reduction by NH3. Adsorption properties were studied by means of temperature programmed desorption (TPD) and FT-IR techniques. FT-IR investigation gave evidence of the presence of strong Lewis acid sites and less strong Bronsted acid sites. The NH3 uptake increased in the presence of water vapour due to an increase in the concentration of surface acid sites and due to some NH3 intercalation. Catalytic activity measurements, performed under diluted feed conditions at T=250–450°C and a contact time of 9×10−3 s, gave NO conversion up to 60%, with small N2O production. Addition of water vapour to the feed caused not only a slight decrease in NO and NH3 conversion but also a marked decrease in N2O formation, thus enhancing the reaction selectivity. This behaviour was ascribed to an inhibiting effect of water on NH3 oxidation.

Fe-vanadyl phosphate (FeVOP) was precipitated in the presence of different amounts of TiO2. The samples also contained Ti(HPO4)2·H2O and probably amorphous FePO4. In the catalysts heat treated at 450°C, besides TiO2 and anhydrous FeVOP, amorphous layered TiP2O7 was likely present. NH3 adsorption sites with medium and high strength were detected, that were related to Bronsted acidity of a pyrophosphate phase and Lewis acidity of FeVOP. The catalysts were noticeably more active and selective than pure FeVOP. NO conversion was increasing with FeVOP content, reaching 90% value at 400°C with unit selectivity to N2 and NH3/NO reaction ratio close to 1.

Publisher Summary In this chapter, a CuO/TiO2 catalyst vapor (10wt% CuO, specific surface area = 120 m2/g) has been studied in NH3 oxidation. Catalysts based on CuO-TiO2 offer interesting properties among different formulations. However, selectivity to nitrogen can be decreased by the parallel formation of N2O and NO. The behavior of metal oxide catalysts upon these reactions can be influenced by water vapor that is always present in the reacting mixture. NH3 oxidation tests were carried out in a continuous flow fixed bed reactor, operating at atmospheric pressure, and a temperature, ranging from 200 to 350°C, with NH3 concentration in the feed of 200, 350, or 700 ppm; a constant concentration of O2 of 2.7%, a water vapor level, when present, of 400, 700, or 1000 ppm and a contact time of 4.5x10-3 s. In the chapter, NH3 temperature programmed desorption (TPD) spectra obtained with and without water vapor treatment are discussed. The spectrum obtained without water vapor treatment shows a composite peak with maxima at 172 and 258°C. As the CuO content of this catalyst is sufficient for the complete coverage of TiO2 surface, the signal is likely to be because of surface copper oxide species. The spectrum indicates at least two forms of NH3 adsorbed at weak to medium strength on copper oxide species. MS analysis of the effluent showed that NH3 is desorbed intact from the weaker sites, while it is oxidized to some extent to N2 on the stronger ones.

The catalytic activity in the reduction of NO by ammonia in the presence of oxygen (SCR process) is reported for CuO-TiO2 and for different catalysts belonging to the MgO-Fe2O3 system. These materials show high activity even at relatively low temperatures, with a maximum NO conversion near 520 K (CuO-TiO2) and 600 K (MgO-Fe2O3). At higher temperatures, NO conversion is reduced because of the competitive NH3 oxidation by O2 to NOx and N2. The adsorption and transformation of ammonia over these systems has been investigated by FT-IR spectroscopy in vacuum and in contact with oxygen and NO. In all cases ammonia is first coordinated over Lewis sites and later undergoes hydrogen abstraction giving rise either to NH2 amide species or to its dimeric form N2H4, hydrazine, detected over CuO-TiO2 and γ-Fe2O3. Other species tentatively identified as imide NH, nitroxyl HNO, nitrogen anions N−2 and azide anions N−3 are produced further. In the presence of NO, coordinated ammonia rapidly disappears, the above intermediates are not found, and water is produced, showing that the SCR reaction occurred. Ammonia protonation to ammonium ion is not detected at all over these systems. It seems consequently demonstrated that Bronsted acidity is not necessary for the appearance of SCR activity. A comparison with the previously-published data on V2O5-TiO2-based systems is done and mechanisms of ammonia oxidation by oxygen and by NO are proposed.

This paper describes a new murine monoclonal antibody, UN5, raised against human thymocytes. This antibody recognizes a molecule of approximately 45 kDa on thymocytes. Flow cytometric analysis reveals a high intensity of labeling with the majority of thymocytes, whereas only CD20+ cells from peripheral whole-blood samples are weakly stained. Peripheral T cells, granulocytes, platelets and red blood cells do not express this antigen, while monocytes are only weakly labeled by UN5. Furthermore, the UN5 antibody discriminates between different types of B-cell malignancies, reacting with a subgroup of B-cell chronic lymphocytic leukemias and hairy cell leukemias, but not with the other kinds of hematopoietic malignancies tested. Antibody UN5 should prove a useful tool for the study of T-cell precursors and for analysis of both normal and neoplastic B cells.

Bcl2-associated athanogene 3 (BAG3) protein is a member of BAG family of co-chaperones that interacts with the ATPase domain of the heat shock protein (Hsp) 70 through BAG domain (110-124 amino acids). BAG3 is the only member of the family to be induced by stressful stimuli, mainly through the activity of heat shock factor 1 on bag3 gene promoter. In addition to the BAG domain, BAG3 contains also a WW domain and a proline-rich (PXXP) repeat, that mediate binding to partners different from Hsp70. These multifaceted interactions underlie BAG3 ability to modulate major biological processes, that is, apoptosis, development, cytoskeleton organization and autophagy, thereby mediating cell adaptive responses to stressful stimuli. In normal cells, BAG3 is constitutively present in a very few cell types, including cardiomyocytes and skeletal muscle cells, in which the protein appears to contribute to cell resistance to mechanical stress. A growing body of evidence indicate that BAG3 is instead expressed in several tumor types. In different tumor contexts, BAG3 protein was reported to sustain cell survival, resistance to therapy, and/or motility and metastatization. In some tumor types, down-modulation of BAG3 levels was shown, as a proof-of-principle, to inhibit neoplastic cell growth in animal models. This review attempts to outline the emerging mechanisms that can underlie some of the biological activities of the protein, focusing on implications in tumor progression.

The aim of this study was to characterize a newly identified transcript named air (AX538681) whose genomic sequence is missing in human genome draft. air was identified as a differentially expressed cDNA in TNFα-stimulated Jurkat cells, transfected with a IkBα-hyperexpressing vector, versus control cells (Turco et al, 2007). Indeed air expression appeared to be induced by a pro-apoptotic stimulus and repressed by NF-κB activity. Air cDNA was isolated by differential screening analysis of an expression library from Jurkat cells; its sequence (3.4kb long, 79% A/T rich) didn't show any similarity with annotated sequences except the homology with an EST (U74659) from human neuroblastoma cells and a 98% identity with traces from chimpanzee WGS database. This evidence suggested that air could belong to an un-sequenced region, whose secondary structure results in cloning instability. Air sequence is detectable by Southern blot and PCR, providing the evidence of its presence in human genome (in press). air genomic 3’ and 5’ flanking regions (each one ∼2.2kb long) were isolated by vectorette PCR and sequenced to allow the synthesis of a probe (∼8kb long) suitable to perform a FISH assay. Preliminary experiments, performed on a thyroid cancer cell line, showed that air localize on Chr. 22. Moreover, we found that air transcript is longer than 3.4kb, since air 5’ flanking region is detectable by RT-PCR on total RNA (unpublished). Four main putative ORFs were identified by ORF-Finder tool, but the aminoacidic sequence of three of them did not show any homology with conserved structural motifs while the fourth, localized on the new isolated 5’ transcript end, showed a transmembrane-like motif. Anyway, we don't exclude that air could be a long ncRNA (but it is not the Air described by Nagano et al, 2008), in fact, it is rich in stop codons, it's strongly predisposed to form stem loop secondary structures and its expression coincides with pro-apoptotic events (submitted). Air role in modulating cell apoptosis was investigated: air silencing in lymphoma, neuroblastoma and AML cells, treated with stressful stimuli, showed a significant (p These findings identify air as a novel potential tool for enhancing cancer response to therapeutics. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3034. doi:10.1158/1538-7445.AM2011-3034

Cells of the human erythroleukemia cell line K562 constitutively secrete a factor that inhibits human T lymphocyte proliferation induced via CD 3 Ti . The factor, termed K-TIF (K562-derived T cell inhibitory factor) is produced in either the presence or absence of fetal calf serum in cultures of K562 cells and can be precipitated by 70% NH 4 SO 4 . Gel flitration chromatography on Superose 12 resin by FPLC showed that the inhibitory factor has a molecular weight of approximately 30–35 kDa. A protein of this size, metabolically labeled with [ 35 S]methionine, specifically bound human peripheral blood mononuclear cells. Chromatofocusing with Mono P by FPLC (pH gradient 7.2–5) indicates that the inhibitory factor has an isoelectric point of 6.0–6.4.

Correction to: Leukemia (2007) 21, 2557–2559; doi:10.1038/sj.leu.2404837 Since the publication of this paper, the authors have noticed errors. Dr P Bonelli (Tumour Institute, ‘Fond. Pascale’, Naples, Italy) should have been listed as an author. M Davenia was incorrectly listed as M d'Avenia. The correct list of authors is shown above.