Background: Many drugs when conjugated with DNA by covalent or noncovalent
interaction form highly reactive, site specific delivery species called drug-DNA adduct.
Objective: The objective of the present review is to highlight the importance and utility of
DNA – drug conjugates for site-specific delivery in anti-cancer therapy.
Results: Drugs, such as doxorubicin, cisplatin, ellipticine, melphalan, tamoxifen, etc. were
reacted with endosomal formaldehyde to form an intermediate Schiff base. The Schiff
base can successfully interact with the exocyclic amino group of guanine nucleotides, resulting
in drug-DNA adducts through the aminal linkage. This mechanism has been extended
to in vitro adduct formation of anthracycline drugs with deoxyguanosine group of
DNA, which is highly stable at low temperature and in physiological pH.
Conclusion: The adduct would gradually release the drug at a physiological temperature
and is thus well suited for site-specific targeted drug delivery with reduced side effects.