Inhibition of the aurora kinases suppresses in vitro NT2-D1 cell growth and tumorigenicity.
The aurora kinase family members, Aurora-A, -B, and -C (listed as AURKA, AURKB and AURKC respectively in the HUGO Database), are serine/threonine kinases involved in the regulation of chromosome segregation and cytokinesis, and alterations in their expression are associated with malignant cell transformation and genomic instability. Deregulation of the expression of the aurora kinases has been shown to occur also in testicular germ cell tumors (TGCTs) identifying them as putative anticancer therapeutic targets. We here evaluated the in vitro effects of MK-0457, an aurora kinases inhibitor, on cell proliferation, cell cycle, ploidy, apoptosis, and tumorigenicity on the TGCT-derived cell line NT2-D1. Treatment with MK-0457 inhibited cell proliferation in a time- and dose-dependent manner, with IC(50)=17.2+/-3.3 nM. MK-0457 did not affect the expression of the three aurora kinases, but prevented their ability to phosphorylate substrates relevant to the mitotic progression. Time-lapse experiments demonstrated that MK-0457-treated cells entered mitosis but were unable to complete it, presenting after short time the typical features of apoptotic cells. Cytofluorimetric analysis confirmed that the treatment with MK-0457 for 6 h induced NT2-D1 cells accumulation in the G(2)/M phase of the cell cycle and the subsequent appearance of sub-G(0) nuclei. The latter result was further supported by the detection of caspase-3 activation following 24-h treatment with the inhibitor. Finally, MK-0457 prevented the capability of the NT2-D1 cells to form colonies in soft agar. In conclusion, the above findings demonstrate that inhibition of aurora kinase activity is effective in reducing in vitro growth and tumorigenicity of NT2-D1 cells, and indicate its potential therapeutic value for TGCT treatment.
Ulisse
Salvatore
S
Department of Experimental Medicine, Sapienza University of Rome, 00161 Rome, Italy.
Arlot-Bonnemains
Yannick
Y
Baldini
Enke
E
Morrone
Stefania
S
Carocci
Silvia
S
Di Luigi
Luigi
L
D'Armiento
Massimino
M
D064096:Aurora Kinase A; D064107:Aurora Kinase B; D064108:Aurora Kinase C; D064127:Aurora Kinases; D018929:Cell Culture Techniques; D045744:Cell Line, Tumor; D002468:Cell Physiological Phenomena / Q000187:drug effects*; D002471:Cell Transformation, Neoplastic / Q000187:drug effects; D006657:Histones / Q000187:drug effects; D006801:Humans; D010766:Phosphorylation / Q000187:drug effects; D010879:Piperazines / Q000494:pharmacology*; D011003:Ploidies; D017346:Protein Serine-Threonine Kinases / Q000037:antagonists & inhibitors* / Q000378:metabolism; D008941:Spindle Apparatus / Q000187:drug effects; D003521:Cyclopropanes; D011720:Pyrazoles; D011743:Pyrimidines
D064096:Aurora Kinase A; D064107:Aurora Kinase B; D064108:Aurora Kinase C; D064127:Aurora Kinases; D006657:Histones; D010879:Piperazines; D017346:Protein Serine-Threonine Kinases; C484810:tozasertib; D003521:Cyclopropanes; D011720:Pyrazoles; D011743:Pyrimidines; C576917:AURKA protein, human; C576921:AURKB protein, human; C576927:AURKC protein, human