Preclinical testing of selective Aurora kinase inhibitors on a medullary thyroid carcinoma-derived cell line.

Abstract

Deregulated expression of the Aurora kinases (Aurora-A, B, and C) is thought to be involved in cell malignant transformation and genomic instability in several cancer types. Over the last decade, a number of small-molecule inhibitors of Aurora kinases have been developed, which have proved to efficiently restrain malignant cell growth and tumorigenicity. Regarding medullary thyroid carcinoma (MTC), we previously showed the efficacy of a pan-Aurora kinase inhibitor (MK-0457) in impairing growth and survival of the MTC-derived cell line TT. In the present study, we sought to establish if one of the Aurora kinases might represent a preferential target for MTC therapy. The effects of selective inhibitors of Aurora-A (MLN8237) and Aurora-B (AZD1152) were analyzed on TT cell proliferation, apoptosis, cell cycle, and ploidy. The two inhibitors reduced TT cell proliferation in a time- and dose-dependent manner, with IC50 of 19.0 ± 2.4 nM for MLN8237 and 401.6 ± 44.1 nM for AZD1152. Immunofluorescence experiments confirmed that AZD1152 inhibited phosphorylation of histone H3 (Ser10) by Aurora-B, while it did not affect Aurora-A autophosphorylation. MLN8237 inhibited Aurora-A autophosphorylation as expected, but at concentrations required to achieve the maximum antiproliferative effects it also abolished H3 (Ser10) phosphorylation. Cytofluorimetry experiments showed that both inhibitors induced accumulation of cells in G2/M phase and increased the subG0/G1 fraction and polyploidy. Finally, both inhibitors triggered apoptosis. We demonstrated that inhibition of either Aurora-A or Aurora-B has antiproliferative effects on TT cells, and thus it would be worthwhile to further investigate the therapeutical potential of Aurora kinase inhibitors in MTC treatment.

• Authors: Chiara Tuccilli, Enke Baldini, Natalie Prinzi, Stefania Morrone, Salvatore Sorrenti, Angelo Filippini, Antonio Catania, Stefania Alessandrini, Roberta Rendina, Carmela Coccaro, Massimino D'Armiento, Salvatore Ulisse
• Journal: Endocrine (Endocrine) Vol. 52 Issue 2 Pg. 287-95 (May 2016) ISSN: 1559-0100 [Electronic] United States
• PMID: 26215279 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• 2-((3-((4-((5-(2-((3-fluorophenyl)amino)-2-oxoethyl)-1H-pyrazol-3-yl)amino)quinazolin-7-yl)oxy)propyl)(ethyl)amino)ethyl dihydrogen phosphate
• Azepines
• MLN 8237
• Organophosphates
• Pyrimidines
• Quinazolines
• Aurora Kinase A
• Aurora Kinase B

Topics

• Aurora Kinase A (antagonists & inhibitors)
• Aurora Kinase B (antagonists & inhibitors)
• Azepines (pharmacology, therapeutic use)
• Carcinoma, Neuroendocrine (drug therapy)
• Cell Cycle (drug effects)
• Cell Line, Tumor
• Cell Proliferation (drug effects)
• Drug Screening Assays, Antitumor
• Humans
• Organophosphates (pharmacology, therapeutic use)
• Pyrimidines (pharmacology, therapeutic use)
• Quinazolines (pharmacology, therapeutic use)
• Thyroid Neoplasms (drug therapy)