Translocation of genes into the pericentromeric heterochromatin occurs during cellular differentiation and leads to a long-term silencing of these genes. Consequently, a structural remodelling of this heterochromatin compartment is observed during differentiation but this remains to be defined from a topological point of view. In a previous study, we analysed the three-dimensional (3D) distribu...

The coumarin esculetin shows antioxidant action on some cell types, both by scavenging ROS and by decreasing ROS production. We have previously demonstrated the induction of apoptosis by esculetin on NB4 human leukaemia cells by an ill-defined mechanism related to ROS levels. In this work, we analyze the effect of the simultaneous treatment with esculetin and two oxidants to observe the early e...

OBJECTIVE To investigate the cytotoxic effects of suberanilohydroxamic acid (vorinostat) in combination with arsenic trioxide (ATO) on the human NB4 cell line in vitro. METHODS The rates of cell proliferation following treatment with vorinostat with or without ATO were measured. Flow cytometry of Annexin-V/propidium iodide double-stained cells was used to measure apoptosis. Acridine Orange an...

BACKGROUND Breast cancer is the most common neoplasm in women and the most frequent cause of death in those between 35 and 55 years of age. All multicellular organisms have an innate immune system, whereas the adaptive or 'acquired' immune system is restricted to vertebrates. This study focused on the effect of conditioned medium isolated from cultured breast cancer cells on NB4 neutrophil-like...

Anaplasma phagocytophilum is a gram-negative obligate intracellular bacterium that persists within neutrophils. We assessed the impact of A. phagocytophilum infection in NB4 promyelocytic leukemic cells using high-density oligoarray, two-dimensional differential gel electrophoresis and liquid chromatography-mass spectrometry. Our Affymetrix data revealed that A. phagocytophilum altered the expr...

Recently, arsenic trioxide (As2O3) was reported to induce clinical remission in patients with acute promyelocytic leukemia. Modulation of protein phosphorylation by binding to the vicinal thiols has been suggested as a possible mechanism. We found that phenylarsine oxide, a strong vicinal thiol-binding agent, neither induced nuclear fragmentation or DNA laddering nor increased caspase activity ...

AIM To investigate the gene expression profiles of acute promyelocytic leukemia (APL) cell line NB4 treated with arsenic trioxide (As2O3) using cDNA microarray. METHODS Two cDNA probes were prepared through reverse transcription from mRNA of NB4 cells treated with or without arsenic trioxide. The probes were labeled with Cy3 and Cy5 fluorescence dyes individually, hybridized with cDNA microar...

Human C/EBPe is a newly cloned gene coding for a CCAAT/ mRNA. Nuclear run-off assays and half-life studies showed that accumulation of C/EBPe mRNA by 9-cis RA was due enhancer binding protein that may be involved in the regulation of myeloid differentiation. Our studies showed that levto enhanced transcription. Furthermore, this C/EBPe mRNA accumulation did not require synthesis of new protein ...

Nuclear localization signal retinoic acid receptor alpha(NLS-RARα), which forms from the cleavage of promyelocytic leukemia-retinoic acid receptor alpha(PML-RARα) protein by neutrophil elastase(NE), possesses an important role in the occurrence and development of acute promyelocytic leukemia(APL). However, the potential mechanism underlying the effects of NLS-RARα on APL is still not entirely c...