OTS964 is a novel TOPK(T–lymphokine-activated killer cell–originated protein kinase) inhibitor.

>98%

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

OTS-964 HCL

Powder

DMSO : ≥ 83.33 mg/mL (194.26 mM)
H2O : 1.43 mg/mL (3.33 mM; Need ultrasonic)

TOPK

OTS964 inhibits the growth of TOPK-positive cells with low IC50 values , whereas its growth inhibitory effect against TOPK-negative HT29 cancer cells is significantly weaker, with IC50 of 290nM. Although OTS964 reveals some suppressive effect on Src family kinases, the response to OTS964 in these cancer cells is not correlated with the expression of Src family kinases c-Src, Fyn, and Lyn, supporting the TOPK-dependent growth inhibitory effects of OTS964. Time lapse imaging in T47D cells shows that treatment with OTS964 induces cytokinesis defects followed by apoptosis.

Although administration of the free compound induces hematopoietic adverse reactions (leukocytopenia associated with thrombocytosis), the drug delivered in a liposomal formulation effectively causes complete regression of transplanted tumors without showing any adverse reactions in mice. Inhibition of TOPK activity with the liposomal OTS964 suppresses tumor growth through induction of cytokinesisdefects and subsequent apoptosis. Although oral administration of OTS964 causes some hematopoietic toxicity, this is a transient effect. The spontaneous recovery from leukocytopenia is occured and the anticancer effectiveness of the oral drug is similar to that of the liposomal formulation, oral administration of the drug may prove to be more practical.