Figure 2.

ACF is a TOPI and TOPIIA inhibitor

(A–D) Agarose gels of the TOP assays with 500 ng pUC19 vector with human recombinant TOPI (A), TOPIIA (B), or 2.5 μg nuclear extract containing native TOPs (C and D). Assays were performed in the presence of ACF or doxorubicin (DOX) and camptothecin (CPT) at a final concentration of 10 μM, and DNA was stained with ethidium bromide. H₂O and DMSO served as positive controls showing TOP activity.