INHIBITION OF THE c-Myc ONCOGENE BY THE AUREOLIC ACID GROUP ANTIBIOTICS
GC-rich stretches in the DNA minor groove are the established intracellular targets for the aureolic acid group of antibiotics such as olivomycin A and its semi-synthetic analogue olivamide. We demonstrated here that both antibiotics at nanomolar concentrations inhibited transcription of the c-Myc oncogene in cultured human tumor cells. The mechanism of transcriptional inhibition did not require the full length binding site for Sp1, a GC-dependent transcriptional factor. GC quartets with the nucleotide sequences optimal for drug binding are sufficient for c-Myc transcriptional block by the aureolic acid derivatives.