TNFSF10 and breast cancer: But recent studies indicate that most varieties of cancer cells, including ovarian cancer, urothelial cancer, pancreatic cancer, colon cancer, prostate cancer [7]–[10] and half of breast cancer cell lines (all of the ER positive breast cancer cell lines, most Her-2 positive cell lines and few triple negative cell lines that exhibit epithelial phenotype), are resistant to the apoptotic effects of TRAIL [11].