MK-5108

Biological Activity

MK-5108 (VX-689) is a highly selective aurora-A kinase inhibitor with an IC50 of 0.064 nM. MK-5108 inhibits Aurora-A activity in an ATP-competitive manner. MK-5108 shows robust selectivity against the other family kinases Aurora-B (220-fold) and Aurora-C (190-fold) in the biochemical assay. MK-5108 also reveals high selectivity for Aurora-A over other protein kinases. Consistent with the induction of pHH3-positive cells, MK-5108 induces accumulation of cells in the G2-M phase. MK-5108 inhibits the proliferation of tumor cells including HCC1143, AU565, MCF-7, HCC1806 and CAL85-1 with an IC50 of 0.42 μM, 0.45 μM, 0.52 μM, 0.56μM and 0.74 μM, respectively.MK-5108 decreases cell viability in a dose-dependent fashion in all three cell lines including LEIO285, LEIO505 and SK-LSM1 cells with an IC50 of approximately 100 nM. Incubation with MK-5108 in LEIO285 increases the proportion of cells in G2/M at 48 and 72 hours post-treatment. MK-5108 significant increases in Caspase 3/7 activity when compared to DMSO-treated control cultures at both time points. In LEIO505 cells, MK-5108 leads to more cells accumulating at G2/M phases at 24 hours but not 48 hours or 72 hours. MK-5108 arrests ULMS cell lines at M phase MK-5108 decreases the IC50 of gemcitabine in LEIO285 cells, but elevates IC50 of gemcitabine in LEIO505 and SK-LMS1 cells. MK-5108 treatment results in the induction of pHH3 in tumor and skin tissues, which starts at 2 hours and reachs a maximum at 4 hours. MK-5108 treatments at 15 mg/kg and 30 mg/kg results in significant tumor growth inhibition with the change in mean tumor volume for the treatment group as a percentage of the mean change in the control group (%T/C) of 10% and −6% at day 11, and 17% and 5% at day 18, respectively. MK-5108 is well tolerated at both doses, with minimal reduction in body weight. MK-5108 also exhibits significant antitumor activity through intermittent dosing in nude rats bearing SW48 tumors, MK-5108 at 15 mg/kg and 45 mg/kg causes dose-dependent tumor growth inhibition with a %T/C of 35% and 7% at day 10, and 58% and 32% at day 27, respectively. Although MK-5108 alone reveals little antitumor activity, the combination of MK-5108 with docetaxel displays greater antitumor activity: %T/C of −42% and −28% at day 6 and day 10, respectively. In the ES-2 tumor, the combination of MK-5108 and docetaxel is also more effective than either agent alone. MK-5108 has been completed in a phase I clinical trial for the treatment of advanced solid tumors.

Protocol (for reference only)

Cell Experiment
Cell lines	HeLa-S3 cells
Preparation method	Synchronizing HeLa-S3 cells at the G1-S phase boundary by double thymidine block with 2 mM thymidine. Washing cells and seeding to 96-well cell culture plates. 4 hours later , an equal volume of medium containing MK-5108 is added to each well. Nocodazole (300 nM) is used as a 100% control. Fixing the cells overnight with cold methanol 12 hours after seeding. Then, staining the cells with rabbit anti-phospho-histone H3 Ser28 antibody and then with anti-rabbit IgG-Cy5. Staining total nucleiwith 10 mg/mL 4′,6-diamidino-2-phenylindole. Using the IN Cell Analyzer1000 with ×10 objective lens to acquire Immunostained images . After acquisition of images, data are analyzed. The %pHH3-positive index is determined by measuring the %pHH3-positive cell counts per total nuclei counts for each sample, then by normalizing with respect to nocodazole-treated cells.
Concentrations	0 μM -1 μM
Incubation time	12 hours

Animal Experiment
Animal models	SCID mice bearing HCT116 tumors
Formulation	0.5% methyl cellulose/0.24% SDS
Dosages	30 mg/kg
Administration	Oral administration

Chemical Information

Molecular Weight	461.94
Formula	C22H21ClFN3O3S
CAS Number	1010085-13-8
Solubility (25°C)	DMSO 90 mg/mL
Storage	Powder          -20°C   3 years ;  4°C   2 years In solvent       -80°C   6 months ;  -20°C   1 month

References

[1] Mingzhu Jiang, et al. Blocking AURKA with MK-5108 attenuates renal fibrosis in chronic kidney disease

[2] Sandhya Noronha, et al. Preclinical evaluation of the Aurora kinase inhibitors AMG 900, AZD1152-HQPA, and MK-5108 on SW-872 and 93T449 human liposarcoma cells

[3] Manik Amin, et al. A phase I study of MK-5108, an oral aurora a kinase inhibitor, administered both as monotherapy and in combination with docetaxel, in patients with advanced or refractory solid tumors

[4] Danielle C Chinn, et al. Anticancer activity of the Aurora A kinase inhibitor MK-5108 in non-small-cell lung cancer (NSCLC) in vitro as monotherapy and in combination with chemotherapies

[5] Toshiyasu Shimomura, et al. MK-5108, a highly selective Aurora-A kinase inhibitor, shows antitumor activity alone and in combination with docetaxel