A low concentration of Hoechst33342 protects cells from death induced by hedamycin

Abstract

<p><b>Copyright information:</b></p><p>Taken from "Molecular mechanism of upregulation of survivin transcription by the AT-rich DNA-binding ligand, Hoechst33342: evidence for survivin involvement in drug resistance"</p><p></p><p>Nucleic Acids Research 2007;35(7):2390-2402.</p><p>Published online 28 Mar 2007</p><p>PMCID:PMC1874665.</p><p>© 2007 The Author(s)</p> () HeLa cells were equally seeded in 24-well plates. Cells grown to 70–80% confluence were treated without (a) and with Hoechst33342 (b), hedamycin (c) or Hoechst33342/hedamycin combination (d) as shown. Note: Hoechst33342 was added 2 h before adding hedamycin. Images were taken 36 h after adding hedamycin. () Trypan blue exclusion assays were used to count the number of alive cells after treatment in (A). Data presented in a histogram are the mean ± SD derived from three independent well countings. () Modulation of survivin promoter activity by hedamycin (Hed) and Hoechst33342 (Hoe) alone and in combination. HeLa cells were transfected with survivin promoter-luciferase construct pLuc-1430. Cells were treated with Hed (0.5 and 1 nM) and Hoe (250 nM) alone or in combination as shown. Luciferase activity was measured 36 h after drug treatment. Each bar in the histogram is the mean ± SD derived from three independent testings. Seq, sequentially (Hed was added to cells after Hoe treatment for 2 h); con, concurrently