The CCN1-blocking antibody suppressed U937 and Kasumi-1 cell survival. U937 and Kasumi-1 cells were treated with the CCN1 antibody or the control antibody (IgG) for 24 hours. (A, B) Cell proliferation was measured using a CCK-8 reagent. (C-D) The percentage of apoptotic cells was determined using Annexin V-APC/PI staining. (E) Western blotting in cells treated with antibodies (0.5 μg/ml) for 24 hours. β-actin served as the loading control. (F-G) Jurkat cells were treated with the CCN1 antibody, and proliferation and apoptosis were measured. **p < 0.01.