The differential protein analysis of 15 samples of CCA patient bile and 10 samples of cholangitis patient bile using two-dimensional electrophoresis and MS/MS analysis, and five different proteins of PGAM1, PDIA3, HSPD1, SSP411 and APOM were randomly selected and validated in bile and tissues; it was found that they had had the same expression trends in bile and tissues [135]. Here, SPATA20 is linked to cholangiocarcinoma.