http://dx.doi.org/10.4314/tjpr.v11i5.4
Abstract
Purpose: To explore the use of restriction
inhibition assay (RIA) to study the binding specificity
of some anticancer drugs.
Methods: A 448 bp DNA fragment derived from
pBCKS+ plasmid (harboring the polylinker region with
multiple restriction endonuclease sites) was used as a
template for sequence selective inhibition of the test
drugs. The template was incubated with different
concentrations of anticancer drugs (adriamycin,
daunomycin, mitoxantrone, distamycin-A, berberine and
palmatine) prior to digestion with restriction
endonucleases - HindIII, EcoRI and EcoRV.
Results: Mitoxantrone, adriamycin and
daunomycin showed specificity for HindIII restriction
site (5’-AAGCTT-3’) at 220, 100 and 100 µM
concentration, respectively. Conversely, distamycin-A
showed an affinity for EcoRI (5’-AAATGC-3’) restriction
sites at a concentration of 10 µM. No binding was
observed for berberine and palmatine at a maximum
concentration of 2 mM at HindIII, EcoRI and EcoRV
restriction sites, respectively.
Conclusion:
The inhibition of endonucleases by mitoxantrone,
adriamycin, daunomycin, distamycin-A, provides direct
evidence of the co-existence of concentration and
sequence specificity for drug-DNA interaction as well as
the need to explore the possible use of RIA for
demonstrating the binding specificity of anticancer
drugs.
Keywords: Restriction endonucleases,
Restriction sites, Anticancer drugs, Restriction
inhibition assay (RIA), Binding specificity.
