Self-Triggered Apoptosis Enzyme Prodrug Therapy (STAEPT): Enhancing Targeted Therapies via Recurrent Bystander Killing Effect by Exploiting Caspase-Cleavable Linker.

Abstract

Tumor heterogeneity is associated with the therapeutic failures of targeted therapies. To overcome such heterogeneity, a novel targeted therapy is proposed that could kill tumor populations with diverse phenotypes by delivering nonselective cytotoxins to target-positive cells as well as to the surrounding tumor cells via a recurrent bystander killing effect. A representative prodrug is prepared that targets integrin αvβ3 and releases cytotoxins upon entering cells or by caspase-3. This allows the prodrug to kill integrin αvβ3-positive cells and upregulate caspase-3, which in turn, activates the prodrug to release a cytotoxin that could subsequently diffuse into and kill the neighboring tumor cells. Apoptotic cells further upregulate and release caspase-3, which activate more prodrugs leading to another round of adjacent cell death and caspase-3 release. Thus, the bystander killing effect could occur repeatedly, leading to augmented and widespread anticancer activity. This strategy provides an avenue that could advance the current targeted therapy.

• Authors: Seung Woo Chung, Jeong Uk Choi, Young Seok Cho, Ha Rin Kim, Tae Hyung Won, Peter Dimitrion, Ok-Cheol Jeon, Seong Who Kim, In-San Kim, Sang Yoon Kim, Youngro Byun
• Journal: Advanced science (Weinheim, Baden-Wurttemberg, Germany) (Adv Sci (Weinh)) Vol. 5 Issue 7 Pg. 1800368 (Jul 2018) ISSN: 2198-3844 [Print] Germany
• PMID: 30027061 (Publication Type: Journal Article)