STRAP and intrahepatic cholangiocarcinoma: Then, to investigate whether circPCNXL2 has any effect on the interaction between STRAP and MEK1/2 in ICC, we conducted immunoprecipitation assays with STRAP or MEK1/2 antibodies in circPCNXL2 overexpression or knockdown in both HuCCT1 and RBE cells.