The proapoptotic and antiproliferative effects of scDb-hERG1-β1-TRAIL were observed in breast cancer cells, mainly TRAIL-sensitive TNBC cells, and were higher than those exerted by scDb-hERG1-β1, a soluble TRAIL trimer, and the classic hERG1 blocker E4031. This evidence concerns the gene TNFSF10 and breast carcinoma.