Platinum intercalators of DNA as anticancer agents

The drawbacks of platinum chemotherapy agents cisplatin, carboplatin and oxaliplatin have inspired the development of compounds with different mechanisms of action. Polyaromatic platinum complexes (PPCs) are a promising anticancer alternative; these bind reversibly with DNA through the insertion of a planar aromatic moiety between nucleobases in a process known as intercalation. PPCs have demonstrated remarkably different in vitro behaviour to cisplatin and exhibited cytotoxicity up to one hundred times greater than cisplatin in many cell lines. This microreview primarily discusses 1,10-phenanthroline-based complexes of the type [Pt(PL)(AL)]2+ (where PL is a polyaromatic ligand and AL is an ancillary ligand), including their cytotoxicity, DNA binding behaviour and biological activity in vitro and in vivo. Other PPCs within the field, including dual-mode DNA binders incorporating tethered acridines and other potently cytotoxic complexes are also covered.