title: Targeted nanodrugs for cancer therapy: prospects and challenges.
abstract: The recent advent of nanomedicine holds potential to revolutionize cancer therapy. This innovative discipline has paved the way for the emergence of a new class of drugs based on nanoengineered particles. These "nanodrugs" are designed to greatly enhance drug therapeutic indices. First-generation nanodrugs consisted of conventional anti-cancer drugs loaded into/onto nanoengineered particles (nanocarriers) devoid of targeting features (non-targeted nanodrugs). Non-targeted nanodrugs have provided the opportunity to carry large amounts of drugs, including poorly water-soluble and/or permeable drugs, to several types of tumors, improving the therapeutic index with respect to comparable free drugs. Although effective, the primary delivery mechanism of non-targeted nanodrugs was through passive tissue accumulation, due to pathophysiological differences between tumor-associated and healthy vessels, and through non-specific targeting of cell subsets, posing the danger of off-target binding and effects. Recently, the therapeutic indices of certain anti-cancer drugs were further improved by attaching targeting ligands to nanodrugs (targeted-nanodrugs). Targeted-nanodrugs selectively bind to cognate receptors expressed on target cells and enter cells more efficiently than non-targeted formulations. Although these advancements have been sufficiently beneficial to place targeted-nanodrugs into clinical development for use in cancer therapy, they also come at a price. The addition of ligands to drug-loaded nanocarriers often leads to additional synthesis steps and costs, and more complex biological performance relative to ligand-devoid nanodrugs. Here, we will discuss the benefits and challenges facing the addition of targeting features to nanodrugs for cancer therapy.
authors.forename: Massimo
authors.initials: M
authors.lastname: Bottini
authors.forename: Cristiano
authors.initials: C
authors.lastname: Sacchetti
authors.forename: Antonio
authors.initials: A
authors.lastname: Pietroiusti
authors.forename: Stefano
authors.initials: S
authors.lastname: Bellucci
authors.forename: Andrea
authors.initials: A
authors.lastname: Magrini
authors.forename: Nicola
authors.initials: N
authors.lastname: Rosato
authors.forename: Nunzio
authors.initials: N
authors.lastname: Bottini
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000008:administration & dosage* / Q000737:chemistry / Q000493:pharmacokinetics*; D015195:Drug Design; D006801:Humans; D058990:Molecular Targeted Therapy / Q000379:methods*; D053769:Nanocapsules / Q000008:administration & dosage* / Q000737:chemistry*; D009369:Neoplasms / Q000188:drug therapy* / Q000378:metabolism*
chemical_list: D000970:Antineoplastic Agents; D053769:Nanocapsules