Table 1

VP16-induced topo II isoform complex formation before and after UV treatmenta

UVVP16 (50 μg/ml)p170 signalbp180 signalb
00
+24 ± 238 ± 1.5
20 J/m+8 ± 2.444 ± 3.6
100 J/m+NDc40 ± 1.7
  • a MCF-7 cells were treated with UV irradiation or untreated. After 2 h, cells were treated with 50μ m etoposide (VP16) for 30 min and then followed by the ICT bioassay with topo IIα and topo IIβ antibodies (see“ Materials and Methods”).

  • b Signals are expressed as ng topo II/μg genomic DNA from CsCl gradient peak.

  • c ND, not detectable.