DKK1 and breast cancer: The results consistently demonstrated that antibodies targeting hDKK1 CRD1 led to an activated T cell response and consequently cell cytotoxicity in breast cancer (SKBR3), gastric adenocarcinoma (NCI-N87) and colon cancer (Colo-205) cells, whereas the hDKK1 CRD2 binder, SC52-002, had no effect (Fig. 4F).