AS1411-functionalized delivery nanosystems for targeted cancer therapy

Nucleolin (NCL) is a multifunctional nucleolar phosphoprotein harboring critical roles in cells such as cell proliferation, survival, and growth. The dysregulation and overexpression of NCL are related to various pathologic and oncological indications. These characteristics of NCL make it an ideal target for the treatment of various cancers. AS1411 is a synthetic quadruplex-forming nuclease-resistant DNA oligonucleotide aptamer which shows a considerably high affinity for NCL, therefore, being capable of inducing growth inhibition in a variety of tumor cells. The high affinity and specificity of AS1411 towards NCL make it a suitable targeting tool, which can be used for the functionalization of therapeutic payloaddelivery nanosystems to selectively target tumor cells. This review explores the advances in NCL-targeting cancer therapy through AS1411-functionalized delivery nanosystems for the selective delivery of a broad spectrum of therapeutic agents.