MLN0905 (MLN-0905; MLN 0905) is a novel, potent and selective small-molecule inhibitor of polo-like kinase-1 (PLK1) with potential antineoplastic activity. Its IC50 is 2 nM, which inhibits PLK1. A wide variety of human tumor cells, including DLBCL cell lines, are inhibited in their ability to proliferate by MLN0905. In several DLBCL models, pharmacodynamic pHisH3 modulation and strong antitumor activity are the results of PLK1 inhibition. These findings strongly support testing PLK1 inhibitors as DLBCL anticancer drugs in clinical settings.

Physicochemical Properties

Molecular Formula	C24H25F3N6S
Molecular Weight	486.56
Exact Mass	486.181
Elemental Analysis	C, 59.24; H, 5.18; F, 11.71; N, 17.27; S, 6.59
CAS #	1228960-69-7
Related CAS #	1228960-69-7
PubChem CID	46235922
Appearance	Off-white to yellow solid powder
Density	1.4±0.1 g/cm3
Boiling Point	624.4±65.0 °C at 760 mmHg
Flash Point	331.4±34.3 °C
Vapour Pressure	0.0±1.8 mmHg at 25°C
Index of Refraction	1.640
LogP	4.6
Hydrogen Bond Donor Count	2
Hydrogen Bond Acceptor Count	9
Rotatable Bond Count	6
Heavy Atom Count	34
Complexity	692
Defined Atom Stereocenter Count	0
SMILES	CC1=NC=C(CCCN(C)C)C=C1NC2=NC(C(C=CC(C(F)(F)F)=C3)=C3NC(C4)=S)=C4C=N2
InChi Key	CODBZFJPKJDNDT-UHFFFAOYSA-N
InChi Code	InChI=1S/C24H25F3N6S/c1-14-19(9-15(12-28-14)5-4-8-33(2)3)31-23-29-13-16-10-21(34)30-20-11-17(24(25,26)27)6-7-18(20)22(16)32-23/h6-7,9,11-13H,4-5,8,10H2,1-3H3,(H,30,34)(H,29,31,32)
Chemical Name	2-[[5-[3-(dimethylamino)propyl]-2-methylpyridin-3-yl]amino]-9-(trifluoromethyl)-5,7-dihydropyrimido[5,4-d][1]benzazepine-6-thione
Synonyms	PLK1 inhibitor; MLN0905; MLN 0905; MLN-0905
HS Tariff Code	2934.99.9001
Storage	Powder-20°C 3 years 4°C 2 years In solvent -80°C 6 months -20°C 1 month
Shipping Condition	Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

Biological Activity

Targets	PLK1 (IC50 = 2 nM)
ln Vitro	MLN0905, having an IC50 of 2 nM, is a strong PLK1 inhibitor. MLN0905 has an EC50 of 9 nM, which inhibits cell mitosis. With an EC50 of 29 nM, MLN0905 directly readouts PLK1 inhibition by inhibiting Cdc25C-T96 phosphorylation. HT-29 viability is inhibited by MLN0905, with an LD50 of 22 nM. Reasonable selectivity against a panel of 359 kinases is exhibited by MLN0905.[1] With an IC50 of 3–24 nM, MLN0905 suppresses the viability of a panel of lymphoma cells.[2]
ln Vivo	After receiving MLN0905 (6.25 mg/Kg - 50 mg/Kg, p.o.) for 48 hours, naked mice with HT-29 xenografts exhibit dose-dependent pharmacodynamic responses. When MLN0905 (3.12 mg/Kg – 6.25 mg/Kg, p.o.) is given to OCI LY-19-Luc tumor-bearing mice, there are notable pharmacodynamic responses that peak eight hours after treatment.[1] When treated for 21 days with OCI LY-19-Luc xenografts containing scid mice, MLN0905 demonstrates antitumor efficacy. For the 6.25 mg/kg daily group, the T/C is 0.15.[2]
Enzyme Assay	Thirty microliters of human PLK1 enzymatic reaction were used, along with 50 mM Tris-HCl (pH 8.0), 10 mM MgCl2, 0.02% BSA, 10% glycerol, 1 mM DTT, 100 mM NaCl, 3.3% DMSO, eight microliters of ATP, 0.2 microliters of [γ-33P]-ATP, four microliters of peptide substrate (Biotin-AHX-LDETGHLDSSGLQEVHLA-CONH2), and ten nanoliters of recombinant human PLK1[2–369]T210D. PLK inhibitors or not, the enzymatic reaction mixture is incubated for 2.5 hours at 30 degrees Celsius before being stopped with 20 microliters of 150 mM EDTA. After that, 25μL of the stopped enzyme reaction mixture is put on an Image FlashPlate coated with streptavidin that has 384 wells, and it is left to sit at room temperature for three hours. After three Tween-20 washes (0.02%), the Image Flash Plate wells are read using a Perkin-Elmer Viewlux.
Cell Assay	MLN0905 functions similarly to RNAi knockdown and is a selective PLK1 inhibitor. MLN0905 treatment dramatically increased pHisH3 expression in HT-29 cells, indicating that PLK1 expression was inhibited and cell arrest in the G2/M phase resulted.
Animal Protocol	Tumor (HT29) xenograft model 0-50 mg/kg P.O; daily, QD×3/week
References	[1]. Discovery of a potent and orally bioavailable benzolactam-derived inhibitor of Polo-like kinase 1 (MLN0905). J Med Chem. 2012 Jan 12;55(1):197-208. [2]. MLN0905, a small-molecule plk1 inhibitor, induces antitumor responses in human models of diffuse large B-cell lymphoma. Mol Cancer Ther. 2012 Sep;11(9):2045-53.

Solubility Data

Solubility (In Vitro)

DMSO: ~97 mg/mL (~199.4 mM) Water: <1 mg/mL Ethanol: <1 mg/mL

Solubility (In Vivo)

Solubility in Formulation 1: ≥ 2.5 mg/mL (5.14 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution. For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL. Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution. Solubility in Formulation 2: ≥ 2.5 mg/mL (5.14 mM) (saturation unknown) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), clear solution. For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of 20% SBE-β-CD physiological saline solution and mix evenly. Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution. Solubility in Formulation 3: ≥ 2.5 mg/mL (5.14 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution. For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.  (Please use freshly prepared in vivo formulations for optimal results.)

Preparing Stock Solutions		1 mg	5 mg	10 mg
	1 mM	2.0552 mL	10.2762 mL	20.5524 mL
	5 mM	0.4110 mL	2.0552 mL	4.1105 mL
	10 mM	0.2055 mL	1.0276 mL	2.0552 mL

*Note: Please select an appropriate solvent for the preparation of stock solution based on your experiment needs. For most products, DMSO can be used for preparing stock solutions (e.g. 5 mM, 10 mM, or 20 mM concentration); some products with high aqueous solubility may be dissolved in water directly. Solubility information is available at the above Solubility Data section. Once the stock solution is prepared, aliquot it to routine usage volumes and store at -20°C or -80°C. Avoid repeated freeze and thaw cycles.