HI-TOPK-032 is an effective and specific inhibitor of TOPK.

HI-TOPK-032 effectively suppresses both anchorage-dependent and independent growth of colon cancer cells by diminishing ERK-RSK phosphorylation and promoting apoptosis, evidenced by increased levels of p53, cleaved caspase-7, and cleaved PARP. At its highest concentration (5 μM), it also reduces MEK1 activity by 40%, showcasing its potency. While it significantly inhibits TOPK kinase activity, its impact on ERK1, c-jun-NH2-kinase 1, and p38 kinase activities remains minimal. The compound adeptly binds to the ATP-binding site of TOPK, forming hydrogen bonds with GLY83 and ASP151, and engaging in hydrophobic interactions with LYS30, highlighting its specificity and effective mechanism of action.

HI-TOPK-032 (1 or 10 mg/kg; mice) treatment, obviously inhibits HCT-116 tumor growth by more than 60% relative to the vehicle-treated group. Mice are well tolerated with HI-TOPK-032 treatment. The expression of p53 is strongly caused, and phosphorylation of ERK and RSK, a direct downstream protein of ERK. Which is markedly inhibited in the HI-TOPK-032-treated group.