chk1 in 5

Chk1-IN-5 is a highly effective inhibitor of checkpoint kinase 1 (Chk1), which hinders the phosphorylation of Chk1 and effectively suppresses tumor growth in a colon cancer xenograft model[1].

CHK1-IN-12 (Compound example 1-5) is a highly selective and orally active checkpoint kinase 1 (CHK1) inhibitor, demonstrating an in vitro enzyme IC50 of ≤10 nM and a cellular IC50 of ≤50 nM. This compound suppresses the phosphorylation activity of CHK1 kinase, disrupts DNA damage response pathways, and induces tumor cell cycle arrest and apoptosis. CHK1-IN-12 shows promise for cancer research applications.

LD2 is a protein arginine methyltransferase 9 (PRMT9; IC50 = 0.9 µM) inhibitor. It can reduce the proliferation ability of Rec-1 and Raji lymphoblast cells, UPN1 mantle cell lymphoma, BL-41 Burkitt lymphoma, and OCI-Ly3 diffuse large B-cell lymphoma (DLBCL) cells (IC50s = 2.5-5 µM). LD2 (2.5 µM) can induce G2/M phase cell cycle arrest in THP-1 acute myeloid leukemia (AML) cells and reduce the phosphorylation levels of checkpoint kinases 1 (Chk1) and Chk2 in their cells.