FAS and cancer: Here we found that U118 expressed RIPK1, a major protein in necroptosis, but very low levels of Fas/CD95, FADD and 57-kDa procaspase-8, critical proteins involved in the extrinsic pathway of apoptosis, as compared to HeLa (human cervical carcinoma) and Jurkat (human acute T-cell leukemia) cells (Fig. 6A and B), two cancer cell lines that readily undergo apoptosis following edelfosine treatment [22, 44].