Design, synthesis, and evaluation of dual EGFR/AURKB inhibitors as anticancer agents for non-small cell lung cancer

The epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) are first-line agents for mutant EGFR-positive (mEGFR+) NSCLC. However, secondary resistant mutations develop following therapy that prevent EGFR-TKI binding. The EGFR-TKIs are rendered ineffective in NSCLC expressing EGFR resistant mutations (rmEGFR+). Mutations in Kirsten rat sarcoma virus protein (mKRAS) support persistent signaling downstream of EGFR regardless of EGFR-TKI earlier in the signaling cascade. The EGFR-TKIs are ineffective in mKRAS+ NSCLC. Thus, newer anticancer agents are needed for rmEGFR+ and mKRAS+ NSCLC. Aurora kinase B (AURKB) is a mitosis related kinase that is overexpressed in NSCLC and supports cancer cell proliferation and survival. Literature reports have suggested that AURKB inhibitors if given concurrently with an EGFR-TKI could overcome EGFR-TKI resistance in mKRAS+ NSCLC and rmEGFR + NSCLC, and showed improved anticancer effects compared to current single-targeted EGFR-TKIs. Molecular modeling was used to identify similarities between the kinase pockets of EGFR and AURKB. An overlap was observed for the inactive conformation of EGFR and the active conformation of AURKB. Compounds 3-7 were synthesized as dual EGFR/AURKB inhibitors for mKRAS+ and rmEGFR+ NSCLC. Compounds 5, 6 and 7 were identified as dual EGFR/AURKB inhibitors. Compound 5 demonstrated modest micromolar inhibition of rmEGFR+ NSCLC. All investigated compounds showed moderate inhibition of mKRAS+ NSCLC cells. Compound 7 demonstrated single-digit micromolar inhibition of mKRAS+ NSCLC.

Abstract 5337: Design, synthesis and evaluation of dual-targeted mEGFR and AURK inhibitors as anticancer agents

Mutant epidermal growth factor receptor (mEGFR) inhibitors constitute the recommended therapy for mEGFR-positive cancers. However, resistance has developed to mEGFR inhibitors due to newer mutations within the enzyme pocket and redundant signaling pathways that bypass mEGFR inhibition. Recent studies have shown that resistance to mEGFR inhibitors could be overcome if given in combination with aurora kinase (AURK) inhibitors. Dual EGFR/AURK kinase inhibitors provide a novel approach to overcome resistance to EGFR inhibitors. In a previous study, Kurup et al. identified 1 as a nanomolar mEGFR inhibitor. Using a structure-based design approach, novel analogs of 1 that incorporated varied sidechains for dual mEGFR and AURK inhibition were designed. The synthesis of the target compounds involved microwave-assisted, copper and palladium catalyzed coupling reactions. This study led to the identification of dual-targeted mEGFR/AURKA and mEGFR/AURKB inhibitors, and compounds with sub-micromolar cellular potencies. The design, synthesis, kinase inhibitory activities and anticancer effects of these novel analogs will be presented. Structure-activity relationships for mEGFR, AURKA and AURKB inhibition will be defined.

Citation Format: Dayna Gesinski, Sonali Kurup. Design, synthesis and evaluation of dual-targeted mEGFR and AURK inhibitors as anticancer agents. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 5337.