Radiosynthesis and evaluation of [11C]AG-488, a dual anti-angiogenetic and anti-tubulin PET ligand. (15th October 2022)

• Record Type: Journal Article
• Authors: Dileep Kumar, J.S.; Molotkov, Andrei; Carberry, Patrick; Chaly, Thomas; Neelamegam, Ramesh; Mintz, Akiva
• Is Part Of: Bioorganic & medicinal chemistry letters. Volume 74(2022)
• Publication Date: 2022-10-15
• Subjects: PET -- RTK -- Tubulin -- Cancer; PET Positron Emission Tomography -- RTK Receptor thymidine kinase; Bioorganic chemistry -- Periodicals; Pharmaceutical chemistry -- Periodicals; 572
• DOI: 10.1016/j.bmcl.2022.128941
• Languages: English
• ISSNs: 0960-894X

Abstract

Graphical abstract: Highlights: Alteration of RTK and tubulins are implicated in the pathogenesis of brain and periphery diseases. AG-488 is an anti-angiogenetic and anti-tubulin agent. [ 11 C]AG-488 is a dual anti-angiogenetic targeting RTK and anti-tubulin PET ligand. [ 11 C]AG-488 exhibit high brain uptake and retention in mice. [ 11 C]AG-488 exhibit higher uptake during blocking conditions. Abstract: Combinations of antiangiogenic and cytotoxic agents show promising results in the treatment of cancer. However, there is a lack of single agent with both antiangiogenic and cytotoxic activities for clinical application. AG-488 aka FLAG-003 is a novel ligand with established antiangiogenetic properties via activation of receptor thymidine kinase (RTK) and anti-tubulin properties in tumor cells. AG-488 is also reported to reduce tumor volume and prolong survival in preclinical animal models of glioblastoma multiforme, breast cancer and is in clinical stage. Higher expression of RTKs and tubulins is reported in various cancers. This study reveals the development of [ 11 C]AG-488, a high affinity dual target inhibitor binding to RTK and anti-tubulin activities. We rationale that antiangiogenic RTK and anti-tubulin activity of [ 11 C]AG-488 may enhance the tumor to tissue ratio, assisting in cancer drug development. [ 11 C]AG-488 was synthesized in 35 ± 5 % radiochemical yield by radiomethylating the corresponding phenolate using [ 11 C]CH3 I. MicroPET studies in mice indicated blood-brain barrier penetration of [ 11 C]AG-488 and retention in the brain. However, blocking studies with antitubulin and RTK agent HD-800 and microtubule depolymerizing agent MPC-6827 show increased binding of [ 11 C]AG-488 in brain. The pattern of tracer binding in blocking conditions is similar to the baseline conditions. The higher binding may be due to the increased plasma uptake of radiotracer or the formation of more free tubulins due to microtubule dynamic instability during the blocking conditions.