PLK4 (polo-like kinase 4)

CFI-400945 is a potent, orally active antitumor agent with the IC50 and Ki values of 2.8 and 0.26 nM, respectively. It has no significant inhibition against PLKs 1-3 is observed for CFI-400945 at a concentration of 50 μM. CFI-400945 can attenuate the growth of breast cell line, as well as other tumor cell lines significantly. CFI-400945 selectively inhibits PLK4 in cells, but also has certain activity against AURKB, TRKA, TRKB and Tie2/TEK (only 10 kinases showed more than 50% inhibition among 290 kinases). The cytokinesis failure and subsequent polyploidization by CFI-400945 treatment indicate that the cell death in cancer cell lines is at least partly achieved through inhibition of AURKB. No significant inhibition is observed for PLKs 1-3 (IC50s > 50 μM) probably due to the most divergent structure of PLK4 compared to other polo-like kinases 1-3. Cancer cells treated with CFI-400945 exhibit effects consistent with PLK4 kinase inhibition, including dysregulated centriole duplication, mitotic defects, and cell death.

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Kinase Assay: Active PLK4 is purified and used to measure PLK4 activity, using an indirect ELISA detection system. PLK1, PLK2, PLK3, AURKA, and AUKB/INCENP compound inhibition are determined using FRET-based homogeneous assay kits from Invitrogen. The assays are performed with ATP concentrations of 25, 60, and 80 μM, respectively, for PLK1, PLK2, and PLK3 and ATP concentrations of 20 and 128 μM, respectively, for AURKA and AURKB/INCENP.

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Cell Assay: MDA-MB-468, MCF-7, HCC1954, MDA-MB-231, SKBr-3, Cal-51, and BT-20 breast cancer cells are seeded into 96-well plates at 3000, 4000, 4000, 2500, 4000, 3000, and 6000 cells per 80 μL, respectively, 24 h before compound overlay and cultured at 37℃ and 5% CO2. Compounds are prepared as 10 mM stocks in 100% DMSO. Each 10 mM stock is diluted with DMEM (Dulbeccos Modified Eagles Medium) cell growth medium containing 10% FBS such that the final concentrations ranged from 50 nM to 250 μM. Aliquots (20 μL) from each concentration are overlaid to 80 μL of preseeded cells to achieve final concentrations of 10 nM to 50 μM. After 5 d, the cells are fixed in situ by gently removing the culture media and adding 50 μL of ice-cold 10% trichloroacetic acid (TCA) per well and incubation at 4 °C for 30 min. The plates are washed with water five times and allowed to air-dry for 5 min. Then 50 μL of 0.4% (w/v) sulforhodamine B (SRB) solution in 1% (v/v) acetic acid is added to each well, followed by incubation for 30 min at rt. The plates are washed four times with 1% acetic acid to remove unbound SRB and air-dried for 5 min. The SRB is solubilized with 100 μL of 10 mM Tris pH 10.5 per well, and absorbance is read at 570 nm. The percentage (%) of relative inhibition of cell viability is calculated.

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Exhibits potent inhibition of PLK4 with a Ki of 0.26 nM and an IC50 of 2.8 nM. It does not significantly inhibit PLK1, PLK2, or PLK3 at concentrations up to 50 µM, demonstrating high selectivity for the PLK4 target.

CFI-400945 is well tolerated in breast cancer xenograft models, in particular those deficient in the tumor suppressor PTEN. Upon intermittent oral dosing, in a mouse model of colon cancer, CFI-400945 is an effective inhibitor of HCT116 tumor growth and was well tolerated. CFI-400945 is absorbed rapidly after oral administration, reaching maximum plasma concentrations (Cmax) of 0.25-11.68 μg/mL for the doses tested (3.75-104 mg/kg). CFI-400945 can inhibit the growth of a range of tumor types and may be effective in a clinical setting even in advanced tumors. Following oral administration of efficacious doses of CFI-400945 in mice, plasma levels of CFI-400945 are sustained and remained above both the EC50 value for half-maximal inhibition of cellular PLK4 autophosphorylation and growth inhibition GI50 values for 24 hr. Moreover, CFI-400945 demonstrates dose-dependent antitumor activity. Analysis of xenograft tumors from mice treated with an efficacious dose of CFI-400945 shows a pharmacodynamic effect that is suggestive of complete rather than partial inhibition of PLK4 kinase activity.

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Demonstrates significant antitumor efficacy in mouse xenograft models, attenuating the growth of breast, lung, ovarian, and colon cancer cell lines through the induction of mitotic defects, dysregulated centriole duplication, and apoptosis. Enhanced efficacy is observed in PTEN-deficient models.

Enzyme activity was measured using purified PLK4 in an indirect ELISA, while counter-screens against PLK1-3 and AURKA/B were performed using FRET-based assay kits to confirm selectivity and potency.

In cellular assays, CFI-400945 inhibited PLK4 autophosphorylation at serine 305 with an EC50 value of 12.3 nM in HCT116 cells overexpressing FLAG-tagged full-length PLK4. Cancer cells treated with the compound exhibited dysregulated centriole duplication, mitotic defects, and cell death.

Dissolved in 30% PEG400/70% deionized water; 10 mg/kg; oral administration Adult female athymic CD1 nude mice

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Oral administration of CFI-400945 at doses of 3.0 and 9.4 mg/kg in mice bearing human cancer xenografts resulted in significant, well-tolerated inhibition of tumor growth. Pharmacokinetic analysis showed rapid absorption after oral administration.

J Med Chem.2015;58(1):147-69;Eur J Med Chem.2015;95:35-40;Cancer Cell.2014;26(2):163-76.

Osimertinib is a polo-like kinase 4 (PLK4) inhibitor with potential antitumor activity. After administration, osimertinib selectively inhibits PLK4, leading to mitotic disorder and apoptosis induction. PLK4 inhibition also prevents cell division and suppresses the proliferation of PLK4-overexpressing tumor cells. PLK4 is a member of the polo family of serine/threonine kinases, overexpressed in various cancer cell types, and plays a crucial role in the regulation of centriole replication during the cell cycle.

C37H38N4O7

650.72

650.274

1616420-30-4

1616420-30-4 (fumarate);1338806-73-7;

58486178

White to yellow solid powder

4.7

2

5

6

40

942

4

C[C@@H]1CN(C[C@@H](O1)C)CC2=CC=C(C=C2)/C=C/C3=NNC4=C3C=CC(=C4)[C@@H]5C[C@]56C7=C(C=CC(=C7)OC)NC6=O

DADASRPKWOGKCU-FVTQAUBDSA-N

InChI=1S/C33H34N4O3/c1-20-17-37(18-21(2)40-20)19-23-6-4-22(5-7-23)8-12-29-26-11-9-24(14-31(26)36-35-29)28-16-33(28)27-15-25(39-3)10-13-30(27)34-32(33)38/h4-15,20-21,28H,16-19H2,1-3H3,(H,34,38)(H,35,36)/b12-8+/t20-,21+,28-,33-/m0/s1

(2'S,3R)-2'-[3-[(E)-2-[4-[[(2S,6R)-2,6-dimethylmorpholin-4-yl]methyl]phenyl]ethenyl]-1H-indazol-6-yl]-5-methoxyspiro[1H-indole-3,1'-cyclopropane]-2-one

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Note: Please store this product in a sealed and protected environment, avoid exposure to moisture.

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

DMSO: 100 mg/mL (187.0 mM)
Water: 1 mg/mL (Insoluble)
Ethanol: 100 mg/mL (187.0 mM)

Solubility in Formulation 1: ≥ 2.5 mg/mL (3.84 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween-80 + 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 DMSO stock solution (25.0 mg/mL) to 400 μL of PEG300 and mix well; then add 50 μL of Tween-80 and mix well; finally add 450 μL of physiological saline and 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.

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Solubility in Formulation 2: ≥ 2.5 mg/mL (3.84 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 DMSO stock solution (25.0 mg/mL) to 900 μL of 20% SBE-β-CD saline and mix well.
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.

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Solubility in Formulation 3: 2.5 mg/mL (3.84 mM) in 10% DMSO + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), Clear solution; Need warming.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of DMSO stock solution (25.0 mg/mL) to 900 μL of corn oil and mix well.

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 (Please use freshly prepared in vivo formulations for optimal results.)