Cl-amidine antagonizes the PAD4-mediated enhancement of the the p300GBD-GRIP1 interaction in a dose-dependent manner. The inhibitory effect of this compound is not a nonspecific one but is targeted at the active PAD4 enzyme. Cl-amidine increases p53 expression in CD45 positive immune cells. It triggers the differentiation and apoptosis of multiple cancer cell lines that are p53+/+ and p53−/− (e.g., HL60, HT29, TK6, and U2-OS cells). Cl-amidine induces the expression of p53 and several downstream target genes including the cyclin dependent kinase inhibitor p21, GADD45, and the proapoptotic protein PUMA in U2-OS osteosarcoma cells.
In vivo
Cl-amidine treatment inhibits NZM(New Zealand mixed 2328) NET(neutrophil extracellular trap) formation in vivo and significantly alters circulating autoantibody profiles and complement levels while reducing glomerular IgG deposition. Further, Cl-amidine increases the differentiation capacity of bone marrow endothelial progenitor cells, improves endothelium-dependent vasorelaxation, and markedly delays time to arterial thrombosis induced by photochemical injury. Cl-amidine delays thrombosis development in NZM mice. It inhibits PADs in mice without significant toxicity and improves disease phenotypes in animal models of inflammatory arthritis and inflammatory bowel disease. And It is shown to reduce disease severity in mouse models of ulcerative colitis and RA.