Aptamers are a group of molecules, which can specifically bind, track, and 
inhibit target molecules, comprising DNA aptamers, RNA aptamers, and peptide 
aptamers. So far, there are much progress about developing novel aptamers and 
their expansile applications. This prospect systematically introduces the 
composition and technological evolution of aptamers, and then focuses on the 
application of aptamers in cancer diagnosis, imaging, and therapy. Following 
this, we discuss the potential to harness aptamers in discovering the biomarker 
of stem cells, which is favorable for us to study the normal developmental or 
abnormal pathological process of tissue and to deliver drugs into target cells 
or tissues in the future.