Potential Applications of Aptamers for Targeting Senescent Cells.

Cellular senescence is a stress response characterized by a permanent loss of proliferative ability. Different types of senescence reflect different forms of stress. Although cellular senescence plays a key role in maintaining tissue homeostasis and in suppressing tumorigenesis, it is widely appreciated that accumulation of senescent cells in tissue contributes to development of age-related dysfunctions and limits the efficacy of chemo- and radiotherapy. Consequently, novel therapeutic strategies targeting senescent cells, or their pro-inflammatory secretome, have been recently developed. The application of these novel therapeutic approaches requires biomarkers for in vivo detection of senescent cells for ageing and age-associated diseases, as well as for therapy-induced senescence in cancer patients. Aptamers are short oligonucleotide or peptide sequences able to bind with high affinity and specificity a wide range of cellular targets, including cell surface epitopes, thanks to their unique three-dimensional folding. Oligonucleotide aptamers have been widely applied for the discovery of biomarkers, since the early 1990s, and Affimers have recently emerged as valuable tools for biomarker discovery. In this chapter we briefly introduce applications of aptamer technologies for recognition of cell surface antigens and suggest that aptamers provide the perfect technology to identify novel senescence-specific biomarkers.