RAD51 and cholangiocarcinoma: 48 gastrointestinal cancer cell lines (18 colorectal, 15 pancreatic, 8 gastric, 5 hepatocellular and 2 cholangiocellular carcinomas) were screened for proximal and distal FA pathway inactivation using FANCD2 immunoblotting, FANCD2 and RAD51 nuclear focus formation (Fig. 1A, Table 1).