Pyrrolidinedithiocarbamate induces apoptosis in human acute myelogenous leukemic cells affecting NF-kappaB activity.

Pyrrolidindithiocarbamate (PDTC), is a metal chelator widely used to study the activation of redox sensitive transcription factors. Recently it has been demonstrated that it manifests pro-oxidant properties. The nuclear factor-Kappa B (NF-kappaB) transcription factor can both promote cell survival and induce apoptosis depending on cell type and context in response to genotoxic stress.

Cell death in human acute myelogenous leukemic cells induced by pyrrolidinedithiocarbamate.

Pyrrolidinedithiocarbamate (PDTC) is a metal chelating compound, which exerts both pro-apoptotic effect and pro-oxidant activity on many cells. Our objective was to investigate whether PDTC was able to interfere with apoptotic process in leukemic and normal bone marrow CD34+ cells. Since hematopoietic growth factors stimulate growth and differentiation and prevent apoptosis, we therefore studied the effect of growth factors pretreatment, such as interleukin-3 and granulocyte-macrophage colony stimulating factor, in human myeloid CD34+ cells to evaluate whether they protect the cells from the apoptotic action of PDTC.

Diminished heme oxygenase potentiates cell death: pyrrolidinedithiocarbamate mediates oxidative stress.

Pyrrolidinedithiocarbamate (PDTC) is a metal-chelating compound that exerts both pro-oxidant and antioxidant effects and is widely used as an antitumor and anti-inflammatory agent. Heme oxygenase-1 (HO-1) is a redox-sensitive-inducible protein that provides efficient cytoprotection against oxidative stress. Because it has been reported that several angiogenic stimulating factors upregulating HO-1 in endothelial cells cause a significant increase in angiogenesis, we investigated the effect of PDTC on cell proliferation and angiogenesis and the effect of overexpression and underexpression of HO-1.

Significance of heme oxygenase in prolactin-mediated cell proliferation and angiogenesis in human endothelial cells.

Our objectives were to determine whether heme oxygenase-1 is a second messenger for prolactin-mediated angiogenesis. Endothelial cell proliferation and angiogenesis assay demonstrated that cell number and capillary formation were increased by prolactin (10 and 25 ng/ml). Both protein synthesis and mRNA analysis confirmed that HO-1 expression was induced by prolactin in cultured endothelial cells and occurred in a concentration-dependent manner.

Haematopoietic progenitors from umbilical cord blood.

Background/aim: The aim of this study is to improve the obstetrician-based cord blood collection system and an efficient recovery of CD34+ haematopoietic progenitor stem cells.

Methods: CD34+ cells were purified from total blood using a positive selection enrichment method, called Mini-Macs.

Results: The final yield of CD34+ cells we obtained was 10(4) cells/ml, with a CD34+ purity of 99%.

Ornithine decarboxylase gene expression in Castleman's disease.

Castleman's disease (CD) is a rare atypical lymphoproliferative disorder that is clinically and histologically heterogeneous and is associated with the risk of developing malignant lymphoma. Based on pathological findings CD is divided into two types: a localized form and a multicentric form. The clinical course differs in these two forms.

Possible role of the transcription factor interferon regulatory factor 1 (IRF-1) in the regulation of ornithine decarboxylase (ODC) gene expression during IFN gamma macrophage activation.

In this report we discuss the role of interferon regulatory factor 1 (IRF-1) in the regulation of ornithine decarboxylase (ODC) transcription during IFN gamma human macrophage activation. We show that a binding sequence for the transcription factor IRF-1 is contained in the first intron of the human ODC gene (from nt +2711 to nt +2722) and we demonstrate that the level of expression of IRF-1 increases in human macrophages and in the human promonocytic cell line, U937, previously differentiated in monocytes/macrophages by phorbol myristate acetate (PMA), after 2 h of IFN gamma stimulation. We also show that the hamster tk-ts13 cell line, stably transfected with the IRF-1 cDNA, over-expresses ODC.