Ribociclib succinate hydrate

Cell experiment:

Cells are grown for 24 hours in 35 mm plates, treated with 500 nM Ribociclib for 6 days, and then fixed and stained overnight. Cells are then imaged for SA-β-gal using an Axio Observer D.1 phase contrast microscope. The percentage of SA-β-gal positive cells is determined by counting the number of positive cells present in three separate microscope frames, and then normalizing to the control. To assess apoptotic activity, cells are plated in triplicate in 96 well plates, treated with Ribociclib, and assayed for caspase 3/7 activation 16 hours after treatment with Caspase-Glo 3/7. Cells treated with SN-38 are used as a positive control[2].

Animal experiment:

Mice[2] The BE2C, NB-1643, or EBC1 cell line-derived xenografts are implanted subcutaneously into the right flank of CB17 SCID-/- mice. Animals bearing engrafted tumors of 200-600 mm3 are then randomized to oral treatment with 200 mg/kg Ribociclib in 0.5 % methylcellulose (n=10) or vehicle (n=10) daily for a total of 21 days. Tumor burden is determined periodically throughout treatment according to the formula (π/6)×d2, where d represents the mean tumor diameter obtained by caliper measurement.

References:

[1]. VanArsdale T, et al. Molecular Pathways: Targeting the Cyclin D-CDK4/6 Axis for Cancer Treatment. Clin Cancer Res. 2015 Jul 1;21(13):2905-10.
[2]. Rader J, et al. Dual CDK4/CDK6 Inhibition Induces Cell-Cycle Arrest and Senescence in Neuroblastoma. Clin Cancer Res. 2013 Nov 15;19(22):6173-82.