Recent Advancements of Aptamers in Cancer Therapy.

Aptamers are chemical antibodies possessing the capability of overcoming the limitations posed by conventional antibodies, particularly for diagnostic, therapeutic, and theranostic applications in cancer. The ease of chemical modifications or functionalization, including conjugations with nucleic acids, drug molecules, and nanoparticles, has made these aptamers to gain priorities in research. In this Mini-review, various reports on therapeutics with aptamer-functionalized nanomaterials for controlled or multistep drug release, targeted delivery, stimuli-responsive drug release, etc. are discussed. In the case of nucleic-acid-conjugated aptamers, DNA nanotrains and DNA beacons are discussed in terms of the possibility of multidrug loading for chemotherapy and gene therapy. Developments with electrochemical aptasensors and signal-enhanced immune aptasensors are also discussed. Further, the future scope of aptamer technology in cancer theranostics and the prevailing limitations are discussed.