Targeting aurora kinase a (AURKA) in cancer: molecular docking and dynamic simulations of potential AURKA inhibitors

Computational identification and experimental characterization of an aurora kinase inhibitor

The serine/threonine kinases of the aurora family are critical for completing various stages of mitotic cell division. They are frequently overexpressed in various cancers, associated with poor prognosis, and have been validated as an attractive drug target. Despite promising preclinical results, the clinical development of small molecule inhibitors targeting aurora kinases is often hampered by limited efficacy as single agents and severe side effects. Recent discoveries of the synthetic interaction of aurora A with various tumor suppressors and its involvement in the development of resistance to third-generation EGFR inhibitors have renewed interest in finding aurora kinase inhibitors. This study utilized computational approaches to discover an aurora kinase inhibitor. Chemical features of two structurally distinct inhibitors of aurora kinase were exploited to develop a molecular shape and color-based model for the virtual screening of small synthetic molecules in the Enamine database. Six hit compounds validated through docking and Molecular Dynamics (MD) simulation studies were evaluated in a cell-based assay. Only MC-688 inhibited both aurora kinases (A and B) and bound to both kinases in a competition binding assay. Analysis of STD-NMR and 2D NOESY spectra confirmed the computationally predicted binding mode of MC-688 with the ATP binding pocket of aurora A. MC-688 inhibited cell proliferation and long-term treatment of HCT116 colorectal cancer cells with MC-688 induced abrogated mitosis, ultimately leading to apoptotic cell death. In conclusion, MC-688 was computationally identified and experimentally validated as a new pan-aurora inhibitor that induces aurora phenotype in cells and can be used as a lead for further optimization.

Research progress on the relationship between AURKA and tumorigenesis: the neglected nuclear function of AURKA

AURKA is a threonine or serine kinase that needs to be activated by TPX2, Bora and other factors. AURKA is located on chromosome 20 and is amplified or overexpressed in many human cancers, such as breast cancer. AURKA regulates some basic cellular processes, and this regulation is realized via the phosphorylation of downstream substrates. AURKA can function in either the cytoplasm or the nucleus. It can promote the transcription and expression of oncogenes together with other transcription factors in the nucleus, including FoxM1, C-Myc, and NF-κB. In addition, it also sustains carcinogenic signaling, such as N-Myc and Wnt signaling. This article will focus on the role of AURKA in the nucleus and its carcinogenic characteristics that are independent of its kinase activity to provide a theoretical explanation for mechanisms of resistance to kinase inhibitors and a reference for future research on targeted inhibitors.

Post-transcriptional control drives Aurora kinase A expression in human cancers

Aurora kinase A (AURKA) is a major regulator of the cell cycle. A prominent association exists between high expression of AURKA and cancer, and impairment of AURKA levels can trigger its oncogenic activity. In order to explore the contribution of post-transcriptional regulation to AURKA expression in different cancers, we carried out a meta-analysis of -omics data of 18 cancer types from The Cancer Genome Atlas (TCGA). Our study confirmed a general trend for increased AURKA mRNA in cancer compared to normal tissues and revealed that AURKA expression is highly dependent on post-transcriptional control in several cancers. Correlation and clustering analyses of AURKA mRNA and protein expression, and expression of AURKA-targeting hsa-let-7a miRNA, unveiled that hsa-let-7a is likely involved to varying extents in controlling AURKA expression in cancers. We then measured differences in the short/long ratio (SLR) of the two alternative cleavage and polyadenylation (APA) isoforms of AURKA mRNA across cancers compared to the respective healthy counterparts. We suggest that the interplay between APA and hsa-let-7a targeting of AURKA mRNA may influence AURKA expression in some cancers. hsa-let-7a and APA may also independently contribute to altered AURKA levels. Therefore, we argue that AURKA mRNA and protein expression are often discordant in cancer as a result of dynamic post-transcriptional regulation.

AURKA promotes renal cell carcinoma progression via regulation of CCNB1 transcription

AURKA is a member of the serine/threonine kinase family and its kinase activity is crucial for the progression of mitosis. Recent studies have highlighted the therapeutic significance of AURKA inhibition in multiple cancer types. However, the specific mechanisms by which AURKA contributes to the progression of renal cell carcinoma (RCC) have not been fully elucidated. In this study, AURKA expression level was identified in human RCC tissues by immunohistochemical (IHC) staining. The function of AURKA on cell malignant phenotypes was evaluated in vitro after AURKA inhibition. The subcutaneous xenograft was conducted to confirm the in vivo effect of AURKA knockdown on growth of RCC cells. Finally, Co-IP, luciferase assay and ChIP experiments were performed to reveal the regulatory mechanism of AURKA on CCNB1. Our results showed a significant upregulation of AURKA in RCC tissues and cell lines, and a high AURKA expression was associated with poor prognosis. AURKA knockdown inhibited RCC cell proliferation and migration, induced cell apoptosis, and led to G1/G2 phase arrest. This effect was further confirmed by the use of an AURKA inhibitor. Mechanistically, AURKA interacted with E2F1, and subsequently recruited it to the promoter region of CCNB1. CCNB1 expression was essential for AURKA-induced RCC progression. Collectively, our results suggested that AURKA plays an important role in development of RCC via regulating CCNB1 transcription.