SB-218078 is less potently inhibits Cdc2 (IC50: 250 nM) and PKC (IC50: 1000 nM). SB-218078 is a potent, ATP-competitive, and cell-permeable checkpoint kinase 1 inhibitor that inhibits Chk1 phosphorylation of cdc25C (IC50: 15 nM).
CBP501 is a peptide with G2 checkpoint-abrogating activity. G2 checkpoint inhibitor CBP501 inhibits multiple serine threonine kinases, including MAPKAP-K2, C-Tak1, and CHK1, that phosphorylate serine 216 of the dual-specific phosphatase Cdc25C (cell division checkpoint 25 C); disruption of Cdc25C activity results in the inhibition of Cdc25C dephosphorylation of the mitotic cyclin-dependent kinase complex Cdc2 cyclin B, preventing entry into the mitotic phase of the cell cycle.
MPT0B214 is a novel and potent microtubule inhibitor with potential anticancer activity. MPT0B214 inhibited tubulin polymerization through strongly binding to the tubulin's colchicine-binding site and had cytotoxic activity in a variety of human tumor cell lines. After treatment with MPT0B214, KB cells were arrested in the G2-M phase before cell death occurred, which were associated with upregulation of cyclin B1, dephosphorylation of Cdc2, phosphorylation of Cdc25C and elevated expression of the mitotic marker MPM-2. Furthermore, the compound induced apoptotic cell death through mitochondria caspase 9-dependent pathway. Notably, several KB-derived multidrug-resistant cancer cell lines were also sensitive to MPT0B214 treatment. ( PLoS One. 2013;8(3):e58953).
Rocaglaol is a potent anticancer drug that induces apoptosis of LNCaP cells through the mitochondrial pathway and its G2 M-phase cell cycle arrest is associated with the down-regulation of Cdc25C and the dephosphorylation of Cdc2. Rocaglaol can reduce tis