title: Targeting to the Bone: Alendronate-Directed Combretastatin A-4 Bearing Antiangiogenic Polymer-Drug Conjugates.
abstract: Selective targeting of tumor site with chemotherapeutic agents appears to be one of the most effective methods to address many of the problems encountered with conventional chemotherapy. In this work, poly(oligoethylene glycol)methacrylate (POEGMA) based bone-targeting polymers bearing an antiangiogenic drug combretastatin A4 (CA4) were synthesized using free radical polymerization. Targeted and nontargeting copolymers were evaluated for their bone targeting efficiency, cytotoxicities against endothelial cells, namely, HUVECs and U2-OS and Saos-2 cancerous cell lines, as well as their antiangiogenic activity against endothelial cell tube formation by HUVECs. It is observed that the drug conjugated polymers conjugated with the bisphosphonate groups containing drug alendronate (ALN) have remarkably high affinity for bone mineral when compared to the polymer-drug conjugates devoid of the bisphosphonate groups. Both targeted and nontargeted polymer-drug conjugates show a sustained drug release in rat plasma with an overall release of 80-93% over 5 days. In vitro studies revealed high levels of cytotoxicity of the polymer-drug conjugates against HUVECs and U2-OS, and moderate cytotoxicity toward Saos-2. Importantly, the CA4 conjugated copolymers displayed excellent level of antiangiogenic activity as deduced from in vitro endothelial cell tube formation assay using HUVECs. Overall, a novel bone-targeting antiangiogenic polymer-drug conjugate that can be further elaborated to carry additional anticancer drugs is disclosed.
authors.affiliation: Department of Chemistry and ‡Center for Life Science and Technologies, Bogazici University , Istanbul 34342, Turkey.
authors.forename: Merve
authors.initials: M
authors.lastname: Karacivi
authors.affiliation: Department of Chemistry and ‡Center for Life Science and Technologies, Bogazici University , Istanbul 34342, Turkey.
authors.forename: Burcu
authors.initials: B
authors.lastname: Sumer Bolu
authors.affiliation: Department of Chemistry and ‡Center for Life Science and Technologies, Bogazici University , Istanbul 34342, Turkey.
authors.forename: Rana
authors.identifier: 0000-0003-4803-5811
authors.initials: R
authors.lastname: Sanyal
mesh_terms: D019386:Alendronate / Q000737:chemistry*; D000970:Antineoplastic Agents / Q000737:chemistry; D001632:Bibenzyls / Q000737:chemistry*; D061307:Human Umbilical Vein Endothelial Cells; D006801:Humans; D008689:Methacrylates / Q000737:chemistry; D011092:Polyethylene Glycols / Q000737:chemistry; D011108:Polymers / Q000737:chemistry*
chemical_list: D000970:Antineoplastic Agents; D001632:Bibenzyls; D008689:Methacrylates; D011108:Polymers; D011092:Polyethylene Glycols; C040105:combretastatin; D019386:Alendronate
keywords: alendronate; antiangiogenic; bone targeting; combretastatin A4; polymer−drug conjugate