title: Folate based radiopharmaceuticals for imaging and therapy of cancer and  inflammation.
abstract: Frequent overexpression of the folate receptor (FR) on a variety of tumor types and on activated macrophages makes this receptor an interesting target for both imaging and therapy of cancer and inflammation. The FR is a glycosylphophatidylinositol-anchored protein that binds the vitamin folic acid with high affinity and internalizes it via endocytosis. In normal tissues and organs, FR-expression is restricted to only a few sites where it is confined to the luminal surface of polarized epithelia and hence does not have access to intra-venously administered folic acid conjugates. Thus, using folic acid as a molecular "Trojan horse" to deliver attached probes to the diseased tissue has emerged as a powerful strategy. A variety of folic acid radioconjugates for potential application in nuclear medicine have been developed and (pre)clinically evaluated during the last two decades. Herein we report on folate receptor targeted tracer design and  in vitro/in vivo investigations using folic acid -targeted radioconjugates suitable for SPECT and PET imaging as well as for potential therapeutic purposes.
authors.affiliation: Center for Radiopharmaceutical Sciences ETH-PSI-USZ, Paul Scherrer Institute. cristina.muller@psi.ch
authors.forename: Cristina
authors.initials: C
authors.lastname: Muller
mesh_terms: D000818:Animals; D016503:Drug Delivery Systems; D015195:Drug Design; D058973:Folate Receptors, GPI-Anchored / Q000378:metabolism*; D005492:Folic Acid / Q000737:chemistry* / Q000378:metabolism; D006801:Humans; D007249:Inflammation / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000473:pathology; D008264:Macrophages / Q000378:metabolism; D009369:Neoplasms / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000473:pathology; D049268:Positron-Emission Tomography / Q000379:methods; D019275:Radiopharmaceuticals / Q000737:chemistry; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods
chemical_list: D058973:Folate Receptors, GPI-Anchored; D019275:Radiopharmaceuticals; D005492:Folic Acid