CHIR-124

Checkpoint kinase 1 (Chk1) regulates S and G₂-M phase cell cycle checkpoints in response to DNA damage. CHIR124 is a cell-permeable, quinolone-based inhibitor of Chk1 (IC₅₀ = 0.3 nM in vitro). It demonstrates high selectivity for Chk1 by displaying inhibitory values 2,000-fold higher against Chk2 (IC₅₀ = 0.7 μM). In synergy with topoisomerase I poisons or ionizing radiation, CHIR124 can inhibit the growth of p53-mutant solid tumor cells both in vitro and in a xenograft model, potentiating tumor apoptosis.

CHIR 124 is a cell-permeable molecule with a quinolone-based structure. It inhibits checkpoint kinase 1 (Chk1) which regulates S and G2-M cekk cycle checkpoints in response to DNA damage. Application towards inhibition of tumor cell growth.

[1]. tse an, rendahl kg, sheikh t, et al. chir-124, a novel potent inhibitor of chk1, potentiates the cytotoxicity of topoisomerase i poisons in vitro and in vivo. clinical cancer research, 2007, 13(2): 591-602.
[2]. tao yg, leteur c, yang cy, et al. radiosensitization by chir-124, a selective chk1 inhibitor effects of p53 and cell cycle checkpoints. cell cycle, 2007, 8(8): 1196-1205.