HDAC10 x HDAC6 x PAK1

Triple-negative breast cancer (TNBC) is the most aggressive breast cancer subtype, and addressing its intrinsic heterogeneity has emerged as a valuable avenue for novel clinical treatment strategy. Here, we put forward an innovative strategy for TNBC treatment by simultaneously suppressing both p21-activated kinase 1 (PAK1) and histone deacetylase (HDAC) class IIb (HDAC6/10). A series of pyrido [2,3-d]pyrimidin-7(8 H )-one moiety derivatives was successfully designed and synthesized to target PAK1/HDAC6/HDAC10 by utilizing structure-based screening and pharmacophore integration. ZMF-25 demonstrates marked inhibitory activity against PAK1, HDAC6, and HDAC10 with respective IC 50 values of 33, 64, and 41 nM, remarkable selectivity over HDACs and PAKs, as well as prominent antiproliferative efficiency in MDA-MB-231 cells. Additionally, ZMF-25 effectively suppresses TNBC proliferation and migration by inhibiting PAK1/HDAC6/HDAC10. Moreover, it was found to impair glycolysis and trigger reactive oxygen species generation, resulting in autophagy-related cell death by inhibiting the AKT/mTOR/ULK1 signaling. Furthermore, ZMF-25 exhibits remarkable therapeutic potential with no obvious toxicity in vivo and good pharmacokinetics. In summary, these observations indicate that ZMF-25 is a novel and potent triple-targeting PAK1/HDAC6/HDAC10 inhibitor, which is expected to provide a novel and effective strategy for TNBC treatment.