HTH-01-091 is a potent and selective maternal embryonic leucine zipper kinase (MELK) inhibitor, with an IC 50 of 10.5 nM. HTH-01-091 also inhibits PIM1/2/3 , RIPK2 , DYRK3 , smMLCK and CLK2 . HTH-01-091 can be uesd for breast cancer research In Vitro HTH-01-091 (1 μM) selectively inhibits 4% of the kinases over 90%. HTH-01-091 (0-10 μM, 1 h) is cell permeable and causes MELK degradation. HTH-01-091 (0-10 μM, 3 day) exhibits minor antiproliferative effects in breast cancer cells. MCE has not independently confirmed the accuracy of these methods. They are for reference only. Western Blot AnalysisCell Line: MDA-MB-468 cells Concentration: 0, 0.1, 1.0, and 10 μM Incubation Time: 1 h Result: Reduced MELK protein levels in MDA-MB-468 cells; Dose-dependently decreased MELK pull-down by streptavidin beads, demonstrating that the compound is cell permeable and binds to MELK in an ATP-competitive fashion. Had no effect on ERK1/2 pull-down, showing no binding affinity of HTH-01-091 to ERK1/2. Cell Proliferation AssayCell Line: MDA-MB-468, BT-549, HCC70, ZR-75-1, MCF7, and T-47D cells Concentration: 0, 0.001, 0.01, 0.1, 1.0, and 10 μM Incubation Time: 3 day Result: Showed antiproliferative activities in a panel of breast cancer cell lines, including MDA-MB-468, BT-549, HCC70, ZR-75-1, MCF7, and T-47D cells, with IC 50 values of 4.00 μM, 6.16 μM, 8.80 μM, >10 μM, 8.75 μM, and 3.87 μM, respectively. IC50& Target:DYRK4 41.8 nM (IC 50 ) PIM1 60.6 nM (IC 50 ) mTOR 632 nM (IC 50 ) CDK7 1230 nM (IC 50 ) PIM2 PIM3