Second-Generation AOH1996 Analogues with Enhanced Pharmacological Properties for Targeting PCNA

Tumor cells express an acidic isoform of the protein (caPCNA), while nonmalignant cells express only a basic isoform (nmPCNA). We previously identified AOH1996 as a first-in-class, orally bioavailable small molecule that selectively inhibits caPCNA-mediated activities.

In this study, second-generation AOH analogues with enhanced pharmacological properties were created through scaffold optimization, with <b>AOH2.60</b> and <b>AOH2.58</b> incorporating 3-methoxy-5-methyl substitutions (Scaffold A) and, respectively, 6-fluoro or 6-cyano on the 1-naphthoyl moiety (Scaffold D). The compounds <b>AOH2.60</b> and <b>AOH2.58</b> exhibited 9.6-fold and 6.6-fold increased potency across multiple cancer cell lines without affecting normal cells, and 38% and 68% greater microsomal stability relative to AOH1996, warranting further development as anticancer therapeutic agents.