Molecular mechanism of inhibition of survivin transcription by the GC-rich sequence-selective DNA binding antitumor agent, hedamycin: evidence of survivin down-regulation associated with drug sensitivity.
Expression of the antiapoptotic protein survivin is associated with cancer cell viability and drug resistance. Thus, control of its expression in cancer cells has significant consequences for cancer therapeutics. Here we have shown that hedamycin, a GC-rich DNA binding drug, down-regulated survivin expression. Using a series of survivin promoter-luciferase constructs, we have identified an 86-bp GC-rich DNA element (-124 to -39) that mediates the ability of hedamycin to down-regulate survivin expression. Furthermore, both in vivo foot-printing and in vitro gel mobility shift experiments revealed that hedamycin bound to a 21-bp GC-rich DNA element (-115 to -95) in the survivin promoter. This drug-DNA interaction abrogated the binding of Sp-1 or Sp1-like proteins to the 21-bp cis-acting DNA element, and mutagenesis of this region consistently diminished survivin promoter activity. Finally, down-regulation of survivin transcription by hedamycin modulated the viability of cancer cells. These data suggest that abrogation of Sp-1 or Sp1-like protein binding to the 21-bp DNA element in the survivin promoter contributes at least in part to the inhibitory effect of hedamycin on survivin gene transcription. Drug-induced modulation of survivin gene expression may provide novel approaches for cancer therapeutics.
Wu
Jianguo
J
Department of Pharmacology, Roswell Park Cancer Institute, Buffalo, New York 14263, USA.
Ling
Xiang
X
Pan
Dalin
D
Apontes
Pasha
P
Song
Lei
L
Liang
Ping
P
Altieri
Dario C
DC
Beerman
Terry
T
Li
Fengzhi
F
D000880:Anthraquinones / Q000494:pharmacology*; D017209:Apoptosis; D020029:Base Pairing; D001483:Base Sequence; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D003110:Colonic Neoplasms; D018983:DNA Footprinting; D004273:DNA, Neoplasm / Q000737:chemistry / Q000235:genetics; D006367:HeLa Cells; D006801:Humans; D051034:Inhibitor of Apoptosis Proteins; D008869:Microtubule-Associated Proteins / Q000187:drug effects / Q000235:genetics*; D008969:Molecular Sequence Data; D009363:Neoplasm Proteins; D016133:Polymerase Chain Reaction; D000077022:Survivin; D014158:Transcription, Genetic / Q000187:drug effects*
D000880:Anthraquinones; C107489:BIRC5 protein, human; D004273:DNA, Neoplasm; D051034:Inhibitor of Apoptosis Proteins; D008869:Microtubule-Associated Proteins; D009363:Neoplasm Proteins; D000077022:Survivin; C001328:hedamycin