Synthetic approaches to DNMT inhibitor SGI-1027 and effects on the U937 leukemia cell line

The known DNMT inhibitor SGI-1027 4 has been synthesized using as key steps Pd-catalyzed Ar-N bond formation reactions performed in a sequential or convergent manner. In the former approach, a by-product, which corresponds to the incorporation of two units of 4-chloroquinoline, was also isolated. The biological effects of compound 4 in the U937 human leukemia cell line are also described.

miRNA-mediated deregulation in leukemia

MicroRNAs (miRNAs) are small non-coding RNAs 18–25 nucleotides (nt) long able to fine-tune post-transcriptional gene expression. Extensive investigation into biogenesis, mechanism of action and functions of miRNAs has clearly revealed their prompt control in developmental timing, differentiation, proliferation, cell death, and metabolism. Deregulation of miRNA-mediated pathways may contribute to pathological conditions such as tumors, including hematological cancers, thus suggesting that miRNAs act both as tumor-suppressor genes (TSG) and oncogenes (OG). Here, we provide an overview of the current understanding of the aberration of miRNA biogenesis, activity, and post-transcriptional control in leukemogenesis.

Molecular analysis of the apoptotic effects of BPA in acute myeloid leukemia cells

Background:

BPA (bisphenol A or 2,2-bis(4-hydroxy-phenol)propane) is present in the manufacture of polycarbonate plastic and epoxy resins, which can be used in impact-resistant safety equipment and baby bottles, as protective coatings inside metal food containers, and as composites and sealants in dentistry. Recently, attention has focused on the estrogen-like and carcinogenic adverse effects of BPA. Thus, it is necessary to investigate the cytotoxicity and apoptosis-inducing activity of this compound.

Methods:

Cell cycle, apoptosis and differentiation analyses; western blots.

Results:

BPA is able to induce cell cycle arrest and apoptosis in three different acute myeloid leukemias. Although some granulocytic differentiation concomitantly occurred in NB4 cells upon BPA treatment, the major action was the induction of apoptosis. BPA mediated apoptosis was caspase dependent and occurred by activation of extrinsic and intrinsic cell death pathways modulating both FAS and TRAIL and by inducing BAD phosphorylation in NB4 cells. Finally, also non genomic actions such as the early decrease of both ERK and AKT phosphorylation were induced by BPA thus indicating that a complex intersection of regulations occur for the apoptotic action of BPA.

Conclusion:

BPA is able to induce apoptosis in leukemia cells via caspase activation and involvement of both intrinsic and extrinsic pathways of apoptosis.