title: Selective Tumor Targeting of Desacetyl Vinblastine Hydrazide and Tubulysin B via Conjugation to a Cholecystokinin 2 Receptor (CCK2R) Ligand.
abstract: As the delivery of selectively targeted cytotoxic agents via antibodies or small molecule ligands to malignancies has begun to show promise in the clinic, the need to identify and validate additional cellular targets for specific therapeutic delivery is critical. Although a multitude of cancers have been targeted using the folate receptor, PSMA, bombesin receptor, somatostatin receptor, LHRH, and αvβ3, there is a notable lack of specific small molecule ligand/receptor pairs to cellular targets found within cancers of the GI tract. Because of the selective GI tract expression of the cholecystokinin 2 receptor (CCK2R), we undertook the creation of conjugates that would deliver microtubule-disrupting drugs to malignancies through the specific targeting of CCK2R via a high affinity small molecule ligand. The cytotoxic activity of these conjugates were shown to be receptor mediated in vitro and in vivo with xenograft mouse models exhibiting delayed growth or regression of tumors that expressed CCK2R. Overall, this work demonstrates that ligands to CCK2R can be used to create selectively targeted therapeutic conjugates.
authors.affiliation: †Department of Chemistry and ‡Center for Drug Discovery, Purdue University, West Lafayette, Indiana 47907, United States.
authors.forename: Charity
authors.initials: C
authors.lastname: Wayua
authors.affiliation: †Department of Chemistry and ‡Center for Drug Discovery, Purdue University, West Lafayette, Indiana 47907, United States.
authors.forename: Jyoti
authors.initials: J
authors.lastname: Roy
authors.affiliation: †Department of Chemistry and ‡Center for Drug Discovery, Purdue University, West Lafayette, Indiana 47907, United States.
authors.forename: Karson S
authors.initials: KS
authors.lastname: Putt
authors.affiliation: †Department of Chemistry and ‡Center for Drug Discovery, Purdue University, West Lafayette, Indiana 47907, United States.
authors.forename: Philip S
authors.initials: PS
authors.lastname: Low
mesh_terms: D000818:Animals; D002460:Cell Line; D045744:Cell Line, Tumor; D005260:Female; D041981:Gastrointestinal Tract / Q000187:drug effects / Q000378:metabolism; D057809:HEK293 Cells; D006801:Humans; D007624:KB Cells; D008024:Ligands; D051379:Mice; D008819:Mice, Nude; D008870:Microtubules / Q000187:drug effects / Q000378:metabolism; D009842:Oligopeptides / Q000494:pharmacology*; D010875:Pipecolic Acids / Q000494:pharmacology*; D043887:Receptor, Cholecystokinin B / Q000378:metabolism*; D054852:Small Molecule Libraries / Q000494:pharmacology; D014747:Vinblastine / Q000494:pharmacology*
chemical_list: D008024:Ligands; D009842:Oligopeptides; D010875:Pipecolic Acids; D043887:Receptor, Cholecystokinin B; D054852:Small Molecule Libraries; C546650:tubulysin B; D014747:Vinblastine
keywords: CCK2R; cholecystokinin 2 receptor; targeted therapy; tubulysin; vinblastine