Entrectinib (RXDX-101) is a Trk, ROS1, and ALK inhibitor that inhibits TrkA, TrkB, TrkC, ROS1, and ALK (IC50=1/3/5/12/7 nM) with oral activity and blood-brain-barrier penetration. Entrectinib exhibits both antitumor and CNS activity.

TrkA:1.7 nM, TrkB:0.1 nM, TrkC:0.1 nM, ALK:1.6 nM

METHODS: Human lung cancer cells HCC78 were treated with Entrectinib (0.1-10 µM) for 72 h, and cell viability was measured by CCK-8 assay.
RESULTS: Entrectinib effectively inhibited cell survival, and the IC50 value of inhibition of HCC78 was 450 nM.[1]
METHODS: Colorectal cancer cells KM12 were treated with Entrectinib (10-250 nmol/L) for 2 h, and the expression levels of target proteins were detected by Western Blot.
RESULTS: Entrectinib eliminated the autophosphorylation of TPM3-TRKA and completely inhibited the phosphorylation of PLCγ1, AKT and MAPK after 2 h of treatment. [2]

METHODS: To assay anti-tumor activity in vivo, Entrectinib (30-60 mg/kg) was administered orally to SCID mice bearing Karpas-299 xenografts twice daily for ten days.
RESULTS: Both dose levels were effective in inducing regression of all tumors to a nonpalpable extent. During the observation period after cessation of treatment at the 60 mg/kg dose, tumor eradication was sustained in four of seven mice at day 80 after the end of treatment, while tumor regeneration was observed in all animals treated with the 30 mg/kg dose. [2]

NLF, NLF-TrkB, SY5Y or SY5Y-TrkB cells are plated in 96 well plates, and they are exposed to drug at different concentrations (1, 5, 10, 20, 30, 50 and 100 nM of entrectinib, 1.5 μM Irino and 50 μM TMZ, respectively) for one hr followed by addition of 100 ng/mL of BDNF. Plates are harvested at 24, 48, and 72 hr following addition of drug. The plates are processed and cell viability is analyzed using a standard SRB assay protocol[2].