Development of hybrid aptamers-engineered PROTACs for degrading VEGF165 in both tumor- and vascular endothelial cells

Abstract

Tumors and angiogenesis are connected through a complex interplay. VEGF165, generated from both tumor and vascular endothelial cells, serves as a mutual benefit for both cell types. Therapeutic approaches modulating VEGF165 have been proposed as promising antitumor therapies. PROTACs are bifunctional molecules that exploit the intracellular ubiquitin-proteasome system to degrade specific proteins. To date, there are no targeted PROTACs designed to degrade VEGF165 in both tumor and vascular endothelial cells. The aptamer AS1411 is notable for its ability to selectively recognize and enter both tumor and vascular endothelial cells by targeting the cell surface nucleolin (NCL). Moreover, AS1411 has also been repurposed as an intracellular recruiter of E3 ligase MDM2 via leveraging NCL as a molecular bridge. In this study, we conjugated AS1411 with a VEGF165-specific aptamer V7t1, creating hybrid aptamers-engineered PROTACs. The PROTACs demonstrate remarkable selectivity for both tumor and vascular endothelial cells and facilitate the ubiquitination and proteasomal degradation of VEGF165. The PROTACs inhibit the growth of tumor cells and also impede angiogenesis, without causing toxicity to normal tissues. The hybrid aptamers-engineered PROTACs provide an avenue for disrupting the tumor-angiogenesis interplay through modulation of VEGF165 in both tumor and vascular endothelial cells.