CPSF2 and hepatocellular carcinoma: The complex incubated in the presence of the nuclear extract (Figure 2B, lane 4), but not in the presence of the buffer (Figure 2B, lane 2), additionally contained a number of bands identified by Western blotting as subunits of the HCC: symplekin, CPSF100, CPSF73 and CstF64 (Figure 2C).