Aptamer guided nanomedicine strategies in prostate cancer: Targeting and diagnosis

Prostate cancer (PCa) is the predominant cancer among men across the globe. Conventional therapies available for PCa suffer from limitations such as lack of target specificity, chemo-resistance, poor tumour extravasation and accumulation. Although ligand conjugated nanocarrier based-drug delivery strategies were well explored in literature, recent studies demonstrated that tumor accumulation of such actively targeted drug delivery systems is marginal (similar to 0.0014%). Therefore, there is a need for improved drug delivery interventions that improve tumor accumulation of nanocarriers. Aptamers possess a certain edge over other ligands owing to their target cell specificity and diminished immunogenic reactions. Further, development and evaluation of aptamers is relatively easy for therapeutic and/or diagnostic applications that in turn encourage aptamer based-drug discovery in pharmaceutical industry. Considering these factors, the authors discussed various biomarkers which could be used for aptamer development in targeting and diagnosis of PCa. Further, the authors mentioned nanocarrier functionalization aspects using aptamers and its role in enhancing prostate cancer-specific cellular uptake. In addition to aforementioned developmental aspects, the authors also highlighted potential bottlenecks that hinder the clinical translation of aptamer-functionalized nanomedicines.