Binimetinib  (Synonyms: MEK162; ARRY-162; ARRY-438162)

MCF7 cells infected as indicated are seeded in 12-well plates (2×10⁴). After 24 hours, cells are treated with BEZ235 (100 or 200 nM), BKM120 (0.75 or 1 μM), GDC-0941 (1 μM), or MK2206 (2 μM) alone or in combination with Binimetinib (MEK162) (1 μM), BI-D1870 (10 μM), or AZD6244 (1 μM), as indicated in text. Cell numbers are quantified by fixing cells with 4% glutaraldehyde or methanol, washing the cells twice in H₂O, and staining the cells with 0.1% crystal violet. The dye is subsequently extracted with 10% acetic acid, and its absorbance is determined (570 nm). Growth curves are performed in triplicate. Viability assays with CellTiter-Glo are performed by plating 2,000 cells in 96-well plates, adding the drug at 24 hours, and assaying 4 to 5 days after drug addition. Cell-cycle and hypodiploid apoptotic cells are quantified by flow cytometry. Briefly, cells are washed with PBS, fixed in cold 70% ethanol, and then stained with propidium iodide while being treated with RNase. Quantitative analysis of sub-G₁ cells is carried out in a FACScalibur cytometer using Cell Quest software^[2].

MCE has not independently confirmed the accuracy of these methods. They are for reference only.

Mice^[2]
Six-week-old female athymic nude Foxn1^nu mice are used. Mice are treated once daily with placebo, BEZ235, BKM120, MK-2206, or Binimetinib (MEK162) by oral gavage. BEZ235 (25-30 mg/kg, 6IW [6 days on 1 day off]) and BKM120 (30 mg/kg, 6IW) are dissolved in 10% NMP-90% PEG, freshly formulated, and administrated within 30 minutes. MK-2206 (100 mg/kg, 3IW) is formulated in 30% Captisol and Binimetinib (MEK162) (6 mg/kg, BID) in 0.5% Tween-80, 1% carboxymethyl cellulose. For tumor growth studies, mice are treated for 7-24 days, depending on the xenograft model and treatment regime. Tumor xenografts are measured with calipers 3 times a week, and tumor volume is determined using the following formula: (length×width²)×(π/6). At the end of the experiment, the animals are anesthetized with 1.5% isofluorane-air mixture and killed by cervical dislocation. Tumors are removed 2 hours following the last administration.
Rats^[1]
Rat collagen-induced arthritis (CIA) and rat adjuvant-induced arthritis (AIA) models are used to determine efficacy in the subacute inflammation setting. In the CIA studies, rats with established disease, induced by injections of Type II collagen, are treated with 0.3, 1 or 3 mg/kg ARRY-438162 (PO, BID) with or without 30 mg/kg ibuprofen (PO, QD) for six days. Body weight and ankle diameter are used to monitor disease progression on days 0-7. The AIA model is induced by an injection of a lipoidal amine in FCA on day 0. The AIA rats are treated with 1, 3 or 10 mg/kg Binimetinib (ARRY-438162) (PO, QD) beginning on day 8 and continuing for 6 days, with or without the addition of 0.05 mg/kg CL14377 (PO, QD) which is dosed days 0-13. Disease progression is monitored on days 7-14 measuring both paw diameter and body weight.

MCE has not independently confirmed the accuracy of these methods. They are for reference only.

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