SPF45, also known as RBM17, is a component of the spliceosome and associates with the lncRNA Saf. In erythroleukemia and cervical carcinoma cells, SPF45-Saf binds to the Fas pre-mRNA and modulates alternative splicing of Fas; this increases soluble Fas, which eventually interacts with Fas ligand to protect cells from apoptosis [46]. Here, FAS is linked to erythroleukemia.