title: Vincristine potentiates the anti-proliferative effect of an aurora kinase inhibitor, VE-465, in myeloid leukemia cells.
abstract: Aurora kinases play an essential role in the regulation of mitosis. The kinases are overexpressed in a variety of cancer cells and are involved in tumorgenesis. Although aurora kinase inhibitors are potential agents for treatment of leukemia, the establishment of efficacious combination therapies is an attractive approach for making good use of these agents. In this study, we examined the effects of a specific aurora kinase inhibitor, VE-465, in combination with various conventional anti-leukemia agents, including doxorubicin, daunorubicin, idarubicin, mitoxantron, cytosine arabinoside, vincristine and etoposide, on acute myeloid leukemia cell lines (HL60, U937, THP-1 and KY821), chronic myeloid leukemia cell lines (KCL22, K562 and KU812) and primary leukemia cells. We found that a combination of VE-465 and vincristine had a synergistic/additive inhibitory effect on the growth of leukemia cells. VE-465 initially increased G2/M-phase cells, followed by induction of sub-G1 cells. Vincristine enhanced this effect of VE-465. The combination of VE-465 and vincristine increased the levels of cleaved caspase 3, cleaved caspase 7, cleaved caspase 9, cleaved PARP and Phospho-Chk2, suggesting that the combination caused Chk2-mediated activation of the G2/M checkpoint, resulting in sequential induction of apoptosis. Interestingly, the combination markedly decreased the level of Phospho-ERK1/2, suggesting that the combination alters a network of cellular signaling pathways. In contrast, combinations of VE-465 and other agents showed no synergistic inhibitory effect but rather had an antagonistic effect. In conclusion, our results indicate the utility of the combination of VE-465 and vincristine as a potential therapy for myeloid leukemia.
authors.affiliation: Jichi Medical University, 3311-1 Yakushiji, Shimotsuke, Tochigi 329-0498, Japan. kozuey@idac.tohoku.ac.jp
authors.forename: Kozue
authors.initials: K
authors.lastname: Yoshida
authors.forename: Tadashi
authors.initials: T
authors.lastname: Nagai
authors.forename: Ken
authors.initials: K
authors.lastname: Ohmine
authors.forename: Mitsuyo
authors.initials: M
authors.lastname: Uesawa
authors.forename: Piyanuch
authors.initials: P
authors.lastname: Sripayap
authors.forename: Yoji
authors.initials: Y
authors.lastname: Ishida
authors.forename: Keiya
authors.initials: K
authors.lastname: Ozawa
mesh_terms: D000970:Antineoplastic Agents / Q000008:administration & dosage / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D064127:Aurora Kinases; D020169:Caspases / Q000378:metabolism; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D004357:Drug Synergism; D004359:Drug Therapy, Combination; D048049:Extracellular Signal-Regulated MAP Kinases / Q000235:genetics / Q000378:metabolism; D005786:Gene Expression Regulation; D006801:Humans; D007951:Leukemia, Myeloid / Q000188:drug therapy* / Q000473:pathology; D010766:Phosphorylation; D010879:Piperazines / Q000008:administration & dosage / Q000494:pharmacology*; D017346:Protein Serine-Threonine Kinases / Q000037:antagonists & inhibitors*; D014750:Vincristine / Q000008:administration & dosage / Q000494:pharmacology*; D003521:Cyclopropanes; D011720:Pyrazoles; D011743:Pyrimidines
chemical_list: D000970:Antineoplastic Agents; D064127:Aurora Kinases; D020169:Caspases; D048049:Extracellular Signal-Regulated MAP Kinases; D010879:Piperazines; D017346:Protein Serine-Threonine Kinases; D014750:Vincristine; C484810:tozasertib; D003521:Cyclopropanes; D011720:Pyrazoles; D011743:Pyrimidines