Inhibition of DNA binding of the NF-Y transcription factor by the pyrrolobenzodiazepine-polyamide conjugate GWL-78.
Many genes involved in cell cycle control have promoters that bind the heterotrimeric transcription factor NF-Y. Several minor-groove binding drugs have been shown to block interactions of transcription factors with cognate DNA-binding sequences. We showed previously that noncovalent minor-groove binding agents block interactions of NF-Y with the promoter of topoisomerase IIalpha (topo IIalpha). In this study, we investigated the ability of GWL-78, a pyrrolobenzodiazepine-poly(N-methylpyrrole) conjugate, to inhibit the binding of NF-Y to DNA. Electrophoretic mobility shift assays showed that GWL-78 could displace NF-Y bound to several CCAAT motifs within promoters of genes involved in cell cycle progression. DNase I footprinting of the topo IIalpha promoter confirmed binding of GWL-78 to AT-rich sequences corresponding to the preferred binding site of NF-Y. Incubation with GWL-78 resulted in displacement of NF-Y binding to DNA. Chromatin immunoprecipitation assays on the topo IIalpha promoter showed that GWL-78 was able to enter the nucleus and interact with specific DNA sequences. Treatment of NIH3T3 cells with GWL-78 resulted in a block of cell cycle progression, which did not involve activation of p53. Thus, agents such as GWL-78 may be useful in modulating transcription and blocking cellular proliferation.
Kotecha
Minal
M
Cancer Research UK Drug-DNA Interac Research Group, UCL Cancer Institute, University College London, London, United Kingdom.
Kluza
Jerome
J
Wells
Geoff
G
O'Hare
C Caroline
CC
Forni
Claudia
C
Mantovani
Roberto
R
Howard
Philip W
PW
Morris
Peter
P
Thurston
David E
DE
Hartley
John A
JA
Hochhauser
Daniel
D
D020816:Amino Acid Motifs; D000818:Animals; D000951:Antigens, Neoplasm / Q000187:drug effects / Q000235:genetics; D000970:Antineoplastic Agents / Q000494:pharmacology*; D001483:Base Sequence; D001569:Benzodiazepines / Q000494:pharmacology*; D001665:Binding Sites; D023081:CCAAT-Binding Factor / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism*; D002453:Cell Cycle; D004247:DNA / Q000378:metabolism*; D004250:DNA Topoisomerases, Type II / Q000187:drug effects / Q000235:genetics; D004268:DNA-Binding Proteins / Q000187:drug effects / Q000235:genetics; D004151:Dipeptides / Q000494:pharmacology*; D024202:Electrophoretic Mobility Shift Assay; D051379:Mice; D008969:Molecular Sequence Data; D041681:NIH 3T3 Cells
D000951:Antigens, Neoplasm; D000970:Antineoplastic Agents; D023081:CCAAT-Binding Factor; D004268:DNA-Binding Proteins; D004151:Dipeptides; C530805:GWL 78; D001569:Benzodiazepines; D004247:DNA; D004250:DNA Topoisomerases, Type II