Abstract 5725: Aurkin-A, a TPX2-Aurora A inhibitor disrupts alisertib-induced polyploidy in HG-diffuse large B cell lymphoma

Abstract Chemotherapy induced polyploidy (CIP) is a mechanism of inherited drug resistance resulting in an aggressive disease course in cancer patients. Alisertib, an Aurora Kinase A (AK-A) ATP site inhibitor, induces cell cycle disruption resulting in polyaneuploidy in high-grade (MYC and BCL2 amplified or expressed) Diffuse Large B Cell Lymphoma (HG-DLBCL). Propidium Iodide cycle flow cytometry was utilized to quantify alisertib induced polyploidy in U2932 and VAL cell lines. In U2932 cells, 1µM alisertib generated 8n+ polyploidy in 48% of the total cell population after five days of treatment. Addition of Aurkin A an AK-A/TPX2 site inhibitor, disrupted alisertib induced polyploidy in a dose-dependent manner with associated increased apoptosis in DLBCL cells. Combination of Aurkin A plus alisertib significantly reduced polyploidy and sensitized DLBCL cells to alisertib. The sensitization of alisertib with Aurkin A through complete AK-A inhibition is of high clinical importance as the alisertib dose can be significantly reduced while preventing polyploidy, enhancing efficacy, and significantly reducing toxicity to normal tissue. In clinical trials of alisertib in lymphoma, a maximum tolerated dose of 1.5µM was achieved. In U2932 cells, we found the addition of 100µM Aurkin A reduced the alisertib IC50 from 983nM to 34nM. We generated a stable FUCCI U2932 cell line expressing Geminin-clover (S/G2/M) and cdt1-mKO (G1), to help monitor cell cycle progression in live cells. Using this system, we identified alisertib-induced polyploidy through endomitosis, which was eliminated with Aurkin A treatment. In a VAL cell line mouse xenograft model, we show polyploidy generation in alisertib treated mice versus vehicle control or Aurkin A. Aurkin A plus alisertib significantly reduced polyploidy and tumor growth compared to vehicle control or Aurkin A levels. Finally, we performed Data-Independent Acquisition Mass Spectrometry on alisertib, Aurkin A, and combination alisertib/Aurkin A treated U2932 cells to identify therapy induced proteomic changes. This proteomic analysis has provided insight into the mechanism of alisertib polyploidy induction and the protective mechanism of within the combination therapy. Our in vitro and in vivo studies show that Aurkin A synergizes with alisertib and significantly decreases the alisertib dose needed to disrupt polyploidy while increasing apoptosis in HG-DLBCL cells. Citation Format: Patrick J. Conway, Bárbara De la Peña Avalos, Jonathan Dao, Sebastian Montagnino, Dmytro Kovalskyy, Eloise Dray, Daruka Mahadevan. Aurkin-A, a TPX2-Aurora A inhibitor disrupts alisertib-induced polyploidy in HG-diffuse large B cell lymphoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5725.