Tumour necrosis factor-related apoptosis-inducing ligand (TRAIL): a possible pathogenic role in chronic plaque psoriasis.

BACKGROUND: Tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) is a cytokine member of the tumour necrosis factor (TNF) family. Its role has been investigated in skin cancers and some inflammatory and/or immune-mediated skin diseases. An involvement of TRAIL in psoriasis pathogenesis has recently been hypothesized. We investigated the expression and localization of TRAIL and its receptors in psoriatic skin and measured serum TRAIL. The intracellular pathways activated by TRAIL were assessed to investigate its potential role in the pathogenesis of psoriasis. METHODS: Twenty-four consecutive patients with plaque psoriasis and age- and sex-matched healthy subjects were recruited. Serum TRAIL was measured by means of an enzyme-linked immunosorbent assay (ELISA). TRAIL and TRAIL receptors were evaluated by reverse transcription - polymerase chain reaction (RT-PCR) (RNA of lesional and non-lesional psoriatic skin) and by immunohistochemistry (lesional skin). Caspase 8 and NF-kB immunoexpression were also evaluated by immunohistochemistry. RESULTS: RT-PCR demonstrated increased synthesis of TRAIL and its receptors in lesional vs. non-lesional skin. Immunohistochemistry showed a strong staining of TRAIL and TRAIL receptors both in the epidermis and in the dermal infiltrate. Finally, a correlation emerged between caspase 8 and TRAIL immunoexpression in the dermis. CONCLUSIONS: Our findings suggest an involvement of TRAIL in psoriasis pathogenesis, probably through an action at the site of the inflammatory infiltrate, likely via caspase 8.

mTOR Activation by PI3K/Akt and ERK Signaling in Short ELF-EMF Exposed Human Keratinocytes.

Several reports suggest that ELF-EMF exposures interact with biological processes including promotion of cell proliferation. However, the molecular mechanisms by which ELF-EMF controls cell growth are not completely understood. The present study aimed to investigate the effect of ELF-EMF on keratinocytes proliferation and molecular mechanisms involved. Effect of ELF-EMF (50 Hz, 1 mT) on HaCaT cell cycle and cells growth and viability was monitored by FACS analysis and BrdU assay. Gene expression profile by microarray and qRT-PCR validation was performed in HaCaT cells exposed or not to ELF-EMF. mTOR, Akt and MAPKs expressions were evaluated by Western blot analysis. In HaCaT cells, short ELF-EMF exposure modulates distinct patterns of gene expression involved in cell proliferation and in the cell cycle. mTOR activation resulted the main molecular target of ELF-EMF on HaCaT cells. Our data showed the increase of the canonical pathway of mTOR regulation (PI3K/Akt) and activation of ERK signaling pathways. Our results indicate that ELF-EMF selectively modulated the expression of multiple genes related to pivotal biological processes and functions that play a key role in physio-pathological mechanisms such as wound healing.

Mutual regulation of TGF-ß1, TßRII and ErbB receptors expression in human thyroid carcinomas.

The role of EGF and TGF-ß1 in thyroid cancer is still not clearly defined. TGF-ß1 inhibited the cellular growth and migration of follicular (FTC-133) and papillary (B-CPAP) thyroid carcinoma cell lines. Co-treatments of TGF-ß1 and EGF inhibited proliferation in both cell lines, but displayed opposite effect on their migratory capability, leading to inhibition in B-CPAP and promotion in FTC-133 cells, by a MAPK-dependent mechanism. TGF-ß1, TßRII and EGFR expressions were evaluated in benign and malignant thyroid tumors. Both positivity (51.7% and 60.0% and 80.0% in FA and PTC and FTC) and overexpression (60.0%, 77.7% and 75.0% in FA, PTC and FTC) of EGFR mRNA correlates with the aggressive tumor behavior. The moderate overexpression of TGF-ß1 and TßRII mRNA in PTC tissues (61.5% and 62.5%, respectively), counteracted their high overexpression in FTC tissues (100% and 100%, respectively), while EGFR overexpression was similar in both carcinomas. Papillary carcinomas were positive to E-cadherin expression, while the follicular carcinomas lose E-cadherin staining. Our findings of TGF-ß1/TßRII and EGFR overexpressions together with a loss of E-cadherin observed in human follicular thyroid carcinomas, and of increased migration ability MAPK-dependent after EGF/TGF-ß1 treatments in the follicular thyroid carcinoma cell line, reinforced the hypothesis of a cross-talk between EGF and TGF-ß1 systems in follicular thyroid carcinomas phenotype.

Cytokines and T cells in atopic dermatitis.

Atopic dermatitis (AD) is an inflammatory disorder of the skin characterized by an impaired immune response. Several effector T cell subsets, such as pro-inflammatory cells like Th9, Th17 and Th22 cells, expressing high levels of IL-9, IL-17 and IL-22, together with the anti-inflammatory, immuno-modulating Treg cells constitutively producing IL-10, seem to play a role in this condition. IL-9 and IL-9 receptors are significantly increased in lesional AD skin compared to normal control skin. In addition, some polymorphisms in IL-9 and IL-9r genes have been associated with AD. The role of IL-17 and IL-17-producing T cells remains under debate and conflicting data are available. IL-22-producing T-cells seem to correlate with the severity of the AD. The number and function of Treg cells, producing IL-10, have been widely investigated in AD with conflicting results. Other studies suggest that high levels of IL-31 or low levels of IL-21 might be involved in the pathogenesis of AD. This review was undertaken in order to provide a better understanding of the relevance of certain cytokines in AD. We have analysed the new insight into the pathogenesis of AD, with special attention to those cytokines produced by the different T cell subpopulations.

Job strain in different types of employment affects the immune response.

The immune system, in cooperation with neuroendocrine functions, defends from cancer and infections mainly by the activity of blood natural killer (NK) cells. Blood NK activity may be influenced by the type of employment since work is the central part of life; moreover, job stress is a situation affecting both neuroendocrine and immune systems. This study examines anxiety (by STAI 1 and 2), job strain (by the Karasek's JCQ) and blood NK activity (by an in vitro radio-isotopic method) of 134 male workers. These men, over 38 years old with stable employment, were working in factories, in construction yards, in offices, as hospital attendants or as self-employed craftsmen. Workers in factories and in construction yards, with high job strain, showed lower NK activity, while office employees, with low job demand, and craftsmen with low anxiety and elevated decision latitude, showed higher NK activity; the level of NK activity of the hospital attendants was between the other groups. In conclusion, this study confirms that the type of employment, related to job stress, affects blood NK activity. Moreover, blood NK activity may be used in the bio-monitoring of workers at high risk.

Effects of palladium nanoparticles on the cytokine release from peripheral blood mononuclear cells of palladium-sensitized women.

OBJECTIVE: To investigate the effects of palladium (Pd) nanoparticles on cytokine release from peripheral blood mononuclear cells (PBMCs) of control or Pd-sensitized nonatopic women. METHODS: TNF-α, IL-5, IL-10 and IFN-γ release and/or expression from PBMCs incubated in presence of 5 to 10 nm Pd nanoparticles or Pd salt (potassium hexachloropalladate) were determined by enzyme-linked immunosorbent assay and reverse transcription-polymerase chain reaction analysis. Transmission electronmicroscopy was performed. RESULTS: In lipopolysaccharide-stimulated PBMCs from controls, Pd salt inhibited IFN-γ and IL-10 release, whereas Pd nanoparticles enhanced IFN-γ release and inhibited TNF-α secretion. In lipopolysaccharide-stimulated PBMCs from Pd-sensitized women showing high IFN-γ release, Pd nanoparticles inhibited TNF-α release and Pd salt IL-10 release. TNF-α and IFN-γ release and messenger RNA expression were correlated. Transmission electronmicroscopy demonstrated uptake of nanoparticles in the endocytic compartment and activation of autophagy. CONCLUSIONS: Palladium ions and nanoparticles exert different effects in vitro on the expression and release of cytokines.

The effect of deproteinized bovine bone on osteoblast growth factors and proinflammatory cytokine production.

OBJECTIVE: To test the ability of Bio-Oss in inducing growth factors and proinflammatory cytokines that may have a role in inflammation after grafting, bone resorption, remodeling and in the homeostasis of osteoblasts. MATERIAL AND METHODS: Normal human osteoblasts were seeded in Petri dishes containing granules of Bio-Oss, cells were harvested after confluency and RNA was extracted. Reverse transcriptase polymerase chain reaction was performed using specific primers for osteonectin, bone sialoprotein (BSP), bone morphogenetic protein (BMP)-2 and BMP-7, platelet-derived growth factor (PDGF), interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-alpha) and integrin beta1. Glycerol-3-phosphate dehydrogenase was used as the housekeeping gene and normal human osteoblasts grown on Petri dishes without Bio-Oss granules were used as negative controls. RESULTS: Osteoblast grown on Bio-Oss showed a normal RNA expression of osteonectin, integrin beta1 and PDGF. However, compared with control osteoblasts it showed a reduced expression of BSP, BMP-2 and BMP-7, IL-6 and TNF-alpha. CONCLUSIONS: Our findings further support the evidence that Bio-Oss is an excellent biomaterial that does not enhance the production of proinflammatory cytokines.

Loss of expression of TGF-beta1, TbetaRI, and TbetaRII correlates with differentiation in human oral squamous cell carcinomas.

Despite advances in biological and molecular characteristics, the prognosis of oral squamous cell carcinomas is still very unfavourable and is based on the classical clinicopathological parameters. However, tumors with similar clinicopathological characteristics may differ dramatically in their clinical outcome. Thus, the identification of novel prognostic factors is necessary to improve prognostic and therapeutic approaches. Transforming growth factor-beta1 (TGF-beta1) is a potent growth inhibitor of epithelial cell proliferation, thus, inactivation of TGF-beta1 signalling may play a role in cancer. The expression levels of TGF-beta1 and its type I and type II receptors (TbetaRI and TbetaRII) were assessed by immunohistochemical and Western blot analyses in 22 oral squamous cell carcinoma lesions, in their normal adjacent mucosa and in the squamous carcinoma cell lines FaDu and CAL27. Immunohistochemistry on 22 oral carcinomas and case-matched normal oral mucosae demonstrated that TGF-beta1, TbetaRI, and TbetaRII were intensively and homogeneously expressed in all normal epithelia. In contrast, TGF-beta1 and its receptors were significantly reduced in poorly (G3) differentiated tumors as compared to moderately (G2) and well differentiated (G1) lesions (p=2.8 x 10(-3), p=1.3 x 10(-3), p=2.8 x 10(-3) and p=1.3 x 10(-3), respectively). The progressive reduction of the expression levels was confirmed by Western blotting. The oral squamous carcinoma cell lines Cal27 and FaDu demonstrated a reduced and a lack of TbetaRI expression, respectively. A significant decrease of TbetaRII expression, as compared to Cal27 cells, was shown in FaDu cells. Thus, the decreased expression of TbetaRII combined with the absence of TbetaRI could account for the resistance of FaDu cells to the growth-inhibiting effect of TGF-beta1. TGF-beta1 and TGF-beta1 receptor expression significantly decreased as tumors became less differentiated and thus more aggressive, suggesting a functional role of these molecules in oral tumor progression.

Human mesothelioma cells exhibit tumor cell-specific differences in phosphatidylinositol 3-kinase/AKT activity that predict the efficacy of Onconase.

Malignant mesothelioma is an aggressive cancer with no known cure, which has become a therapeutic challenge. Onconase is one of few chemotherapeutic agents that have been studied in patients with malignant mesothelioma that has the advantage of low toxicity and limited side effects. Here, we evaluate the effect of Onconase on killing of malignant mesothelioma cells and how the phosphatidylinositol 3-kinase/AKT (PI3-K/AKT) survival pathway influences this effect. Our results show that Onconase induces apoptosis in malignant mesothelioma cell lines and that this effect is tumor cell specific. Malignant mesothelioma cell lines with the highest AKT activation, which correlated with the presence of the SV40 large and small T antigen (SV40+), were the most resistant to the drug. Finally, a cooperative effect was observed between small molecule inhibitors of PI3-K and Onconase in the killing of malignant mesothelioma cells. Our results suggest that kinase screening of individual malignant mesotheliomas for endogenous levels of activated PI3-K/AKT may be predictive of the efficacy of Onconase and possibly other chemotherapeutic agents.

The presence of simian-virus 40 sequences in mesothelioma and mesothelial cells is associated with high levels of vascular endothelial growth factor.

The aim of this study was to evaluate whether the presence of simian virus-40 (SV40) is associated with increased release of vascular endothelial growth factor (VEGF) in human malignant mesothelioma (MM) cells. We studied nine cell lines derived from pleural effusion (PE) of patients with MM, and three different cultures of normal human mesothelial cells (NHMC) derived from pleural fluid of patients with congestive heart failure. NHMC were transfected with full length SV40 (NHMC-FL) or large T antigen (NHMC Tag) DNAs. High levels of VEGF were detected in conditioned media of each of two MM cells that tested positive for SV40 by PCR amplification and Southern blot hybridization and for Tag transcript by reverse transcription- polymerase chain reaction (RT-PCR) and immunoprecipitation. We also found that NHMC-FL released high amounts of VEGF. Conditioned media from SV40-positive MM cells and from FL-NHMC increased proliferation of human umbilical vein cells (HUVEC) and this effect was partially abrogated by adding specific blocking antibodies against VEGF. These results offer the first evidence that SV40 can cause VEGF release in SV40-positive MM cells and that entire viral genome is required for this effect.