MN58b is a selective choline kinase α (CHKα) inhibitor, and results in inhibition of phosphocholine synthesis. MN58b reduces cell growth through the induction of apoptosis, and also has antitumoral activity[1][2].

The IC50s of MN58b for parental and Gemcitabine-resistant Suit2 007 cells are 3.14 µM and 0.77 µM, respectively[1].MN58b (1-5 µM; 72 hours; SK-PC-1, Suit2 008, IMIM-PC2, and RWP-1 cells) has a marked effect on colony formation at 1 µM, and growth is completely abolished at 5 µM in all the cell lines[1].MN58b ((1-10 µM; 24-48 hours; SK-PC-1, Suit2 008, IMIM-PC2, and RWP-1 cells) induces apoptosis and this response correlates with CHKα expression[1]. Cell Viability Assay[1] Cell Line: SK-PC-1, Suit2 008, IMIM-PC2, and RWP-1 cells

MN58b (4 mg/kg; intraperitoneal injection; once a day; for 5 days; MF-1 nude mice) treatment significantly decreases phosphomonoesters in both HT29 and MDA-MB-231 xenografts. Phosphocholine levels are found to correlate with choline kinase activities[2]. Animal Model: MF-1 nude mice with HT29 or MDA-MB-231 cells[2]

[1]. Mazarico JM, et al. Choline Kinase Alpha (CHKα) as a Therapeutic Target in Pancreatic Ductal Adenocarcinoma: Expression, Predictive Value, and Sensitivity to Inhibitors. Mol Cancer Ther. 2016 Feb;15(2):323-33. [2]. Al-Saffar NM, et al. Noninvasive magnetic resonance spectroscopic pharmacodynamic markers of the choline kinase inhibitor MN58b in human carcinoma models. Cancer Res. 2006 Jan 1;66(1):427-34.