The Progress of Growth and Apoptosis Are Associated with Both of AURKA and Aurkb in Marimo Cells with Calr Gene Mutation

Abstract

Objective: Mutations of calreticulin (CALR) are a breakthrough discovery in exon 9 as most common driver mutations in janus kinase 2 (JAK2) or thrombopoietin receptor (MPL)-negative mutant essential thrombocythemia (ET) and primary myelofibrosis (PMF) patients. Several new inhibitors have displayed a relatively good therapeutic prospect after the JAK inhibitors, but still not completely cure the patients on their own. Thus, improvement of the therapeutic effect of these new inhibitors is particularly important through exploration of the related targets, which is probably compensated the function of original target in patients. Methods: The protein level of aurora was detected in CALR mutant patients, and was quantified by calculating the gray value of WB band. The biological function was examined in CALR mutant cell line (MARIMO) after aurora inhibition by EdU staining, colony assay, western blot, Annexin V, and flow cytometry assay, respectively. Transcriptomic analyzed the enriched genes and related signaling pathway in MARIMO cells with knockdown of Aurora A (AURKA) or Aurora B (AURKB). Results: Here, we found that Aurora B, similarly with Aurora A, was activated in CALR mutant patients. Selective inhibition of AURKA with MLN 8237 induced cell-growth arrest, maturation and apoptosis, and this cell phenotype was further enhanced when the AURKB was also inhibited as the increase of inhibitors' concentration. Specific downregulation of AURKB alone showed obvious inhibition on cell growth, and produced a similar effect on CALR mutant cells treated with MLN 8237 or interfered AURKA. Transcriptomic analyses revealed a replication reaction on cells caused by knockdown of AURKA or AURKB, which also induced a similar inhibition for mitogen-activated protein kinase (MAPK) signaling, but activation for metabolic and apoptosis pathway. Conclusion: These results suggested that both of AURKA and AURKB were associated with the progress of growth and apoptosis in MARIMO cells with CALR gene mutation, and provided a reference for recently proposed complementary therapies with Aurora kinase inhibitors in CALR mutated MPNs.