Abstract 1563: Concomitant inhibition of Aurora kinase A and WEE1 kinases results in synergistic tumor control and heightens DNA replication stress in head and neck and lung carcinomas

Abstract

Abstract Human papillomavirus (HPV)-negative head and neck squamous cell carcinoma (HNSCC) and lung cancer mainly harbor disruptive mutations in TP53 and/or CDKN2A tumor suppressor genes, which are associated with refractoriness to treatment as well as poor prognosis and survival. Mutational loss of TP53 function fosters elevated expression of Aurora kinase A (AURKA) that plays a crucial role in mitotic progression at G2/M and stabilizes DNA replication forks at S phase. We have previously demonstrated that combined inhibition of AURKA and WEE1, a G2/M checkpoint kinase induced by replication stress, results in synergistic anti-tumor effects in HNSCC in vitro and in vivo. We have now further confirmed synergy using the highly selective AURKA inhibitor VIC1911 in HNSCC and lung cancers harboring TP53 mutations and explored mechanisms of cell death. VIC1911 and adavosertib combination synergistically suppressed cell growth and survival in both 2D- and 3D-culture systems relative to vehicle or single-agent treatment in TP53-mutated HNSCC FaDu and CAL27, and lung cancer A549 and NCI-H358 cells, with no observable toxicity in normal cells, predicting a favorable therapeutic index. Furthermore, combination treatment accelerated mitotic entry and resulted in accumulation of mitotic catastrophe, as demonstrated by time-lapse imaging, and apoptotic cell death as evidenced by cleaved PARP assays. Notably, we found that combination VIC1911 and adavosertib in HNSCC cells drastically slowed and stalled progression of replication forks in DNA fiber analysis (Mean: DMSO=3.117; adavosertib=1.495; VIC1911=0.9757; combination=0.5548 kb/min; P <0.0001) and amplified DNA damage as measured by γH2AX, indicating induction of severe replication stress. In vivo, this combination resulted in significant tumor regression in both HNSCC and lung adenocarcinoma patient-derived and cancer cell-derived xenografted mice compared with either vehicle or single-agent treatment. Taken together, these results suggest that AURKA inhibition increases dependency on WEE1 by enhancing replication stress and mitotic catastrophe, and support clinical evaluation of combined AURKA and WEE1 inhibition as a novel and effective treatment for HNSCC and lung cancer patients with elevated AURKA expression. Citation Format: Jong Woo Lee, Sundong Kim, Sebastian Cruz-Gomez, Jackie Shi, Cindy Yang, Barbara Burtness. Concomitant inhibition of Aurora kinase A and WEE1 kinases results in synergistic tumor control and heightens DNA replication stress in head and neck and lung carcinomas [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 1563.