Aptamer: A potential oligonucleotide nanomedicine in the diagnosis and treatment of hepatocellular carcinoma

Abstract

Hepatocellular carcinoma (HCC) is one of the most common cancers with a high mortality rate. Late diagnosis and poor prognosis are still a major drawback since curative therapies such as liver resection and liver transplantation are effective only for an early stage HCC. Development of novel molecular targeting therapies against HCC may provide new options that will improve the efficiency of the diagnosis and the success of the therapy, thus ameliorating the life expectancy of the patients. The aptamer is an oligonucleotide nanomedicine that has high binding affinity and specificity to small and large target molecules in the intracellular and extracellular environment with agonist or antagonist function. Currently, several aptamers for diagnostic and therapeutic purposes are under development to recognize different molecules of HCC. In in vitro models, the aptamer has been shown to be able to reduce the growth of HCC cells and increase the sensitivity to conventional chemotherapies. In in vivo mouse models, aptamer could induce cell apoptosis with antitumor activity. Overall data had shown that aptamer has limited toxicity and might be safe in clinical application. This review summarizes recent information of aptamer as a potential oligonucleotide nanomedicine tool, in diagnostics, targeted therapy, and as drug delivery nano-vehicles.

Keywords: aptamer; future therapy; hepatocellular carcinoma; oligonucleotide nanomedicine.

Figure 1. Aptamer applications in cancer medicine

Oligonucleotide aptamer can function as both extra- and intra-cellular targeting molecule, and as antagonist and agonist activating molecule. By using conjugation with imaging probe, drug, or gene-therapy, aptamer can be used as a nano-delivery agent in a direct or indirect system.

Figure 2. Aptamer for HCC diagnostic and targeted therapy

Aptamer can act both as a diagnostic tool in the conjugation with imaging probe and biosensor and a targeted therapy agent by its neutralizing effect and by its combination with antineoplastic drugs and/or gene therapy.