ENPP1 and Familial prostate cancer: To examine the antibody-dependent cellular cytotoxicity (ADCC) of IgG1 17 and 3G12, we first tested the surface expression of ENPP1 on parental HEK293T cells and HEK293T cells isogenically expressing ENPP1 (293T-ENPP1), as well as three different cancer cell lines (human hepatoma cell line HepG2, human prostate cancer cell line PC3, and Ewing Sarcoma cell lines CHLA10) by utilizing a commercial anti-ENPP1 antibody from Abcam (EPR22262-75).