ABCB4 and cholangiocarcinoma: 13 Tougeron Tougeron D D Fotsing Fotsing G G Barbu Barbu V V et al et al ABCB4/MDR3 gene mutations and cholangiocarcinomas ABCB4/MDR3 gene mutations and cholangiocarcinomas J Hepatol J Hepatol 2012 2012 57 57 467 467 468 468 22387667 22387667