Article

c-myc Suppression in Burkitt's lymphoma cells.

Department of Molecular Biotechnology, Lunfberg Laboratory, Chalmers University of Technology, P.O. Box 462, SE 405 30 Göteborg, Sweden.
Biochemical and Biophysical Research Communications (impact factor: 2.48). 02/2002; 290(1):11-5. DOI:10.1006/bbrc.2001.6096 pp.11-5
Source: PubMed

ABSTRACT The purpose of the study was to elucidate how DNA tetraplex (also referred to as G-quadruplex)-forming oligonucleotides mediate suppression of the human c-myc gene at the level of transcription initiation. A 22-base-long oligonucleotide, which is rich in guanines and folds into an intrastrand DNA tetraplex under physiological conditions, was administered to a Burkitt's lymphoma cell line overexpressing a (8:14) translocated c-myc allele. Administration of the oligonucleotide at nanomolar concentrations to the surrounding medium resulted in efficient cellular uptake, and was accompanied by a substantial concentration- and conformation-dependent decrease in growth rate. We discuss how c-myc transcription is initiated at the molecular level and speculate that the oligonucleotide exerts a dual effect on c-myc expression in vivo.

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Keywords

22-base-long oligonucleotide
 
efficient cellular uptake
 
elucidate
 
human c-myc gene
 
intrastrand DNA tetraplex
 
nanomolar concentrations
 
oligonucleotide exerts
 
physiological conditions
 
substantial concentration-
 
suppression
 
vivo
 

Tomas Simonsson