KRT19 and cholangiocarcinoma: The increased expression of CEACAM6, EPCAM, LAMC2, MMP11, KRT7, KRT17, KRT19, SFN, and SOX9 (Figure 4) and the decreased expression of ADH1A, ALDOB, AOX1, CTH, FGA, FGB, FGG, GSTA1, and OTC (Figure 5) were significantly correlated and showed clinical significance for the diagnosis of CCA.