CIB-L43 is a high affinity and orally available TRBP inhibitor (KD = 4.78 nM), which can effectively inhibit the biosynthesis of oncogenic miR-21, increase the expression of PTEN and Smad7, and block the AKT and TGF-β signaling pathways to inhibit the proliferation and migration of hepatocellular carcinoma (HCC) cells.

TRBP-Dicer interaction:2.34 μM, miR-21 biosynthesis (HCC cells):0.66 nM (EC50)

CIB-L43, a 2-phenylthiazole-5-carboxylic acid derivative, binds TRBP with high affinity (KD = 4.78 nM) and disrupts the TRBP-Dicer interaction (IC₅₀ = 2.34 μM). In hepatocellular carcinoma cells, CIB-L43 suppresses oncogenic miR-21 biosynthesis with nanomolar potency (EC₅₀ = 0.66 nM), upregulates tumor suppressors PTEN and Smad7, inhibits AKT and TGF-β signaling, and significantly reduces cell proliferation and migration[1].

In hepatocellular carcinoma mouse models, CIB-L43 showed favorable pharmacokinetics, including an oral bioavailability of 53.9%[1].