Cancer is a hyperproliferative disorder. Numerous
genetic and epigenetic changes are required to transform
normal cells into cancer cells. These alterations control
various signaling pathways that cooperate to enable
cancer cells with a wide range of biological capabilities
required for growing, disseminating and finally killing
their host (6). Although antiproliferative drugs may act
by different mechanisms, apoptosis is the most common
as well as preferred mechanism through which many
antiproliferative agents kill and eradicate cancer cells (7).
Topoisomerases are enzymes that regulate the topological status of DNA and play crucial roles in maintaining
genomic integrity (8). The enzymes relax supercoiled
DNA through transient, protein-linked cleavages of either
one (type I topoisomerase) or both (type II topoisomerase) of the double-stranded DNA strands (9). In addition
to apoptosis, topoisomerase is another important target
of antiproliferative agents (1013).