BCI-121 (C005B-311601)

Biochem/physiol Actions

BCI-121 is a substrate-competitive SMYD3 inhibitor that reduces nuclear histone H3 lys4 di- and tri-methylation level (by 50%/H3K4me2 and 40%H3K4me3 in HT29 cells; 100 μM BCI-121 for 48 h), downregulates known SMYD3 target genes transcription, and selectively affects SMYD3-dependent proliferation of cancer cultures (46%/HT29 and 54%/HCT116 proliferation reduction; 100 μM BCI-121 for 72 h) with little antiproliferation efficacy toward low SMYD3-expressing cancer cells. BCI-121 targets SMYD3 via direct affinity interaction (kon 357.7/M/s; k_off 4.23×10^-3/s; K_D=k_off/k_on = 11.8 μM) and effectively competes against histone for SMYD3 binding (%inhibition/[histone H4 peptide]:[BCI-121] ratio = 36.5%/1:1 and 51.0%/1:2.5).

BCI121 is capable of reducing the mesenchymal signature of MDA-MB-231 cells. It can also decrease their ability to invade in vitro and in vivo.