TCS-PIM-1-4a (SMI-4a) is a pan-Pim kinases inhibitor that blocks mTORC1 activity via activation of AMPK. TCS-PIM-1-4a kills a wide range of both myeloid and lymphoid cell lines (IC50 values ranging from 0.8 μM to 40 μM) [1][2].
TCS-PIM-1-4a (10 μM; 24-48 hours; 6812/2 cells and Jurkat cells) treatment increases the population of cells in the G1 phase from 44.3% to 68.4% and from 56.2% to 67.1% in 6812/2 and Jurkat, respectively. S-phase cells are decreased in 6812/2, whereas only small changes are seen in Jurkat cells consistent with the lesser G1 block[1].TCS-PIM-1-4a (5 μM; 6 hours; 6812/2 cells and Jurkat cells) induces cell death by the induction of apoptosis[1]. TCS-PIM-1-4a (5 μM; 4-8 hours; 6812/2 cells and Jurkat cells) prevents the increase in 4E-BP1 protein levels and inhibits mTOR-directed phosphorylation on Thr37/46[1].
TCS-PIM-1-4a (SMI-4a; 60 mg/kg; oral gavage; twice daily; for 21 days; nu/nu nude mice) treatment causes a significant delay in the tumor growth without any change in the weight, blood counts, or chemistries[1].
References:
[1]. Lin YW, Beharry ZM, Hill EG, et al. A small molecule inhibitor of Pim protein kinases blocks the growth of precursor T-cell lymphoblastic leukemia/lymphoma. Blood. 2010 ;115(4):824-33.
[2]. Beharry Z, Mahajan S, Zemskova M,et al. The Pim protein kinases regulate energy metabolism and cell growth. Proc Natl Acad Sci U S A. 2011;108(2):528-33.