Design and development of an innovative, safe, and highly potent E1 ubiquitin-activating enzyme inhibitor CPL–410-005 conjugate in anticancer therapy

Introduction: Targeting ubiquitin-proteasome system (UPS) has emerged as a rational approach in the treatment of human cancer. The therapeutic potential this pathway been validated by clinical successes bortezomib – first proteasome inhibitor drug implemented therapy multiple myeloma and mantle cell lymphoma. However, solid tumors remains challenging, mostly due to poor tumor-selective delivery low efficacy. Previously, we reported on development novel CPL-410-005 non-selective, permeable, ubiquitin-activating enzyme (E1). To allow specific targeting tumor cells thus reduce off-target effects, developed targeted antibody-drug conjugates (ADC) made from humanized anti-HER2 affibody conjugated with derivatives CPL-410-005. Material method: Two derivatives, CPL-410-077 CPL-410-082, were designed synthesized for preparation ADCs. general synthetic scheme incorporated cleavable glycosidase-sensitive trigger unit intracellular release final cytotoxic agent after endocytosis ADC. Conjugates prepared CPL-410-082 characterized vitro interaction extracellular domain HER2 using surface plasmon resonance stability buffer culture media reversed phase chromatography–mass spectrometry (RP-HPLC). Next, their cytotoxicity selectivity evaluated two adenocarcinoma models high expression HER2: ovarian (SKOV-3) breast (SKBR-3) CellTiter-Glo 2.0 Assay. As control used embryonic kidney line (HEK-293) minimal expression. Results discussion: Yields obtained bioconjugations above 85%. Analytical characterization denaturing RPLC–MS confirmed efficient conjugation homogeneity conjugates. showed improved cellular uptake, selectivity, anticancer activity compared unconjugated receptor overexpressing cancer cells. was displayed only upon cleavage carbohydrate linker. Additionally, HEK293 not affected concentrations required effect tested lines. This implies enhanced safety reducing side effects free derivatives. Conclusion: anti-HER2-CPL-410-077 anti-HER2-CPL-410-082 provide significant selective antitumor against adenocarcinoma. Presented results support further preclinical validation anti-HER2-drug inhibitors therapy. No conflict interest.