Navitoclax (ABT-263)

2 years -80 in solvent

Administered via p.o.

SCLC cell lines

0-1 uM

Formulated in 10% ethanol, 30% polyethylene glycol 400, and 60% Phosal 50 PG

ABT-263 is structurally related to ABT-737, it is a disruptor of Bcl-2/Bcl-xL interactions with pro-apoptotic proteins. Overexpression of the prosurvival Bcl-2 family members is commonly associated with tumor maintenance, progression, and chemoresistance. [1] ABT-263 displays the protection afforded by overexpression of Bcl-2 or Bcl-xL with EC50 values of 60 nM and 20 nM, respectively. [1] A wide range of cellular activity is observed with ABT-263 having a 50% growth inhibition (EC50) of 110 nM against the most sensitive line (H146), whereas its activity in the least sensitive line (H82) results in an EC50 at 22 uM. All four cell lines with EC50 values of <400 nM (H146, H889, H1963, and H1417) are also highly sensitive to ABT-737, and the two most resistant lines (H1048 and H82) are similarly resistant to ABT-263. [2]

48 hours

Human tumor cell lines SCLC cell lines are maintained at 37 C containing 5% CO2. SCLC cell lines are cultured in RPMI 1640 with 10% fetal bovine serum (FBS), 1% sodium pyruvate, 25 mM HEPES, 4.5 g/L glucose, and 1% penicillin/streptomycin. Leukemia and lymphoma cell lines are cultured in RPMI 1640 supplemented with 10% FBS and 1% penicillin/streptomycin. Cells (1-510 4) are treated by ABT-263 for 48 hours in 96-well culture plates in a final volume of 100 L and cytotoxicity is assessed with the CellTiter Glo assay. In vitro cyto toxicity of ABT-263 is assayed.

Navitoclax (ABT-263) is a potent inhibitor of Bcl-xL, Bcl-2 and Bcl-w with Ki of ≤ 0.5 nM, ≤1 nM and ≤1 nM in cell-free assays, but binds more weakly to Mcl-1 and A1. Phase 2.