OTSSP167 is a highly potent MELK inhibitor (IC50 = 0.41 nM) and inhibited the phosphorylation of PSMA1 (proteasome subunit alpha type 1) and DBNL (drebrin-like).

>98%

Store at -20℃ for one year（Powder）；Store at 2-4℃ for two weeks；Store at -20℃ for six months after dissolution.

MELK inhibitor; OTSSP-167; OTSSP 167

Powder

DMSO 0.5 mg/mL warmed (1.02 mM)

MELK

OTSSP167 inhibits A549, T47D, DU4475, and 22Rv1 cancer cells, in which MELK is highly expressed, with IC50 values of 6.7, 4.3, 2.3, and 6.0 nM, respectively. OTSSP167 inhibited the phosphorylation of PSMA1 (proteasome subunit alpha type 1) and DBNL (drebrin-like), which are novel MELK substrates and are important for stem-cell characteristics and invasiveness. OTSSP167 suppresses mammosphere formation of breast cancer cells through the inhibition of PSMA1 phosphorylation.

OTSSP167 exhibits significant tumor growth suppression in xenograft studies using breast, lung, prostate, and pancreas cancer cell lines in mice by both intravenous and oral administration. In MDA-MB-231 model, intravenous administration of OTSSP167 at 20 mg/kg once every two days results in TGI of 73% The oral administration at 10 mg/kg once a day reveals TGI of 72%. OTSSP167 for multiple cancer types in dose-dependent and MELK-dependent manners with no or a little body-weight loss.