HTH-01-015

HTH-01-015 is a selective NUAK1/ARK5 inhibitor (IC₅₀ is 100 nM). HTH-01-015 inhibits NUAK1 with >100-fold higher potency than NUAK2 (IC50 of >10 μM). IC50 & Target: IC50: 100 nM (NUAK1)^[1] In Vitro: HTH-01-015 is a specific NUAK1 inhibitor. The related NUAK1 and NUAK2 are members of the AMPK (AMP-activated protein kinase) family of protein kinases that are activated by the LKB1 (liver kinase B1) tumor suppressor kinase. HTH-01-015 inhibits NUAK1 with an IC₅₀ of 100 nM, but does not significantly inhibit NUAK2 (IC₅₀ of >10 μM). In all cell lines tested, HTH-01-015 inhibits the phosphorylation of the only well-characterized substrate, MYPT1 (myosin phosphate-targeting subunit 1) that is phosphorylated by NUAK1 at Ser⁴⁴⁵. In U2OS cells, HTH-01-015 suppresses proliferation and phosphorylation of MYPT1 to the same extent as shRNA-mediated NUAK1 knockdown. In mouse embryonic fibroblasts (MEFs), treatment with 10 μM HTH-01-015 suppresses proliferation and phosphorylation of MYPT1 to the same extent as NUAK1-knockout. To test whether NUAK1 inhibition impaired the ability of the invasive U2OS cells to enter a matrix, 3D Matrigel Transwell invasion assays demonstrate that 10 μM HTH-01-015 markedly inhibits the invasiveness of U2OS cells in this assay^[1].